Hydroponic cultivation method

Abstract

Provided is a low-cost and full-circulation type hydroponic cultivation technique that enables disease control and suppression of growth disturbance caused by allelopathic substances without requiring pH adjustment.　This hydroponic cultivation method is characterized by comprising adding an extract of a polyphenol-containing plant body or a mushroom extract to a cultivation liquid. The extract of a polyphenol-containing plant body or the mushroom extract is contained in the cultivation liquid in the form of a complex with a trace element. The complex does not precipitate, even when the pH of the cultivation liquid changes, and not only promotes the absorption of the trace element but also exhibits a remarkable antimicrobial effect and controls diseases. In particular, a polyphenol-iron complex has an effect of decomposing organic substances and thus decomposes and removes allelopathic substances.

Description

[Technical Field]

[0001] The present disclosure relates to a hydroponic cultivation method, specifically to a hydroponic cultivation technique that can suppress disease occurrence, promote nutrient absorption, and suppress autointoxication by adding a polyphenol-containing plant extract or a mushroom extract to a culture solution. [Background technology]

[0002] In recent years, hydroponic cultivation (nutrient solution cultivation) systems have become popular in plant factories, etc. The distinctive feature of hydroponic cultivation is that it does not suffer from problems such as continuous crop damage that are seen in soil cultivation, and it can be expected to produce stable crops.

[0003] However, hydroponic cultivation has the disadvantage that once pathogenic microorganisms enter the culture solution, they are difficult to control and can quickly spread throughout the cultivation system, causing extensive damage. Conventionally, sterilization techniques for the culture solution (nutrient solution) using ultraviolet light, ozone, filtration, metallic silver agents, etc. have been proposed as countermeasures against root diseases in hydroponic cultivation (see, for example, Patent Documents 1 and 2).

[0004] Furthermore, with recirculating hydroponic cultivation, the compositional balance of the nutrient solution can become unbalanced as the crops grow, causing problems with the crops' growth. This is because plants actively and selectively absorb water and nutrients according to environmental conditions, growth stage, and growth situation (see, for example, Non-Patent Document 1).

[0005] Here, if nitrate ions are preferentially absorbed, the pH of the nutrient solution rises. Generally, the pH of a nutrient solution suitable for hydroponic cultivation is between 5.5 and 6.5; if the pH is outside this range, the nutrients in the nutrient solution will precipitate and become in a form that cannot be absorbed by the plant. Normally, the pH and electrical conductivity (EC) of a nutrient solution are controlled, but once the compositional balance of the nutrient solution is lost, it cannot be restored.

[0006] To prevent nutrients from precipitating in the nutrient solution, commercially available fertilizers are combined with chelating agents such as EDTA. Chelating agents have multiple coordination sites and form multiple coordinate bonds with metal ions. This makes it difficult for the metal ions to separate from the chelating agent, and they exist as a single molecule, preventing precipitation in the nutrient solution.

[0007] In addition, a phenomenon called allelopathy caused by chemical substances exuded from plant roots is known. Allelopathic substances are believed to function primarily to control pests and to compete with other plants. However, in recirculating hydroponic cultivation, if high concentrations of these allelopathic substances accumulate in the culture solution, it is thought to cause a growth disorder known as "autointoxication" (see, for example, Non-Patent Document 1).

[0008] Furthermore, in the hydroponic cultivation of fruit and vegetables, solid media such as coco peat and rock wool are used to absorb nutrients, but these solid media have problems such as the attachment of pathogens and disposal after cultivation.

[0009] Meanwhile, the present inventors have previously developed polyphenol-iron complexes that can maintain iron in the state of divalent ferrous ions using reducing organic matter, tea leaves, coffee grounds, etc. (See Patent Documents 3 to 7.) These polyphenol-iron complexes are not only useful as Fenton reaction catalysts and divalent ferrous ion supply agents, but also function as photocatalysts that absorb light of a wide range of wavelengths, including visible light, and demonstrate activity (See Patent Documents 8 and 9.) [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Japanese Patent Application Publication No. 2020-10659 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-24012 [Patent Document 3] Patent No. 5733781 [Patent Document 4] Patent No. 5804454 [Patent Document 5] Patent No. 6057227 [Patent Document 6] Patent No. 6179957 [Patent Document 7] Patent No. 6202770 [Patent Document 8] Patent No. 6340657 [Patent Document 9] Patent No. 6478209 [Non-patent literature]

[0011] [Non-Patent Document 1] "Plant Factory Business for a New Era: Improving Profitability and Earnings with Artificial Light Plant Factories, Cultivating Useful Plants, and Utilizing AI / IoT," February 20, 2020, published by Johokko Co., Ltd., pp. 48-49 and 55-57 Summary of the Invention [Problem to be solved by the invention]

[0012] Conventional sterilization techniques for culture solutions all have problems, such as being expensive or not being effective enough. In addition, to physically prevent the intrusion of pathogenic microorganisms, a closed or semi-closed space like a plant factory is required, which is another factor that increases the cost of hydroponic cultivation.

[0013] Furthermore, in recirculating hydroponics, if the composition balance of the nutrient solution is disrupted and the pH changes, nutrients will precipitate and become unavailable for absorption by plants, so pH adjustment of the nutrient solution is essential. Chelated fertilizers such as those mentioned above, such as EDTA, do not require pH adjustment, but are very expensive.

[0014] Therefore, even in conventional recirculating hydroponic cultivation, the nutrient solution has been replaced when productivity declines for the reasons mentioned above, and this "environmentally unfriendly" cultivation method continues.

[0015] Therefore, there was a need to develop a low-cost, fully recirculating hydroponic cultivation technology that could prevent disease and did not require pH adjustment.There was also a need to develop a low-cost method to decompose and remove allelopathic substances that accumulate in the culture solution and cause growth disorders.

[0016] The object of the present disclosure is to provide a low-cost, fully recirculating hydroponic cultivation technology that enables disease control and suppression of growth disorders caused by allelopathic substances, and does not require pH adjustment. [Means for solving the problem]

[0017] To solve the above problems, the present inventors investigated the development of a culture solution for hydroponic cultivation that utilizes the antibacterial, organic matter decomposing, and ferrous ion supplying properties of polyphenol-iron complexes. The present inventors mixed various plant extracts with trace elements essential for plant growth, including iron, to prepare a "plant extract-trace element mixture," and conducted extensive research using this mixture in the hydroponic cultivation of various plants.

[0018] As a result, the present inventors discovered that using this plant extract and trace element mixture in hydroponic cultivation can simultaneously prevent disease and suppress autointoxication. They also discovered that when this plant extract and trace element mixture is used in hydroponic cultivation, growth impairment due to nutrient deficiency does not occur even if the pH of the culture solution changes due to an imbalance in the nutrient solution composition. Furthermore, they discovered that this plant extract and trace element mixture exhibits a more pronounced antibacterial effect than a polyphenol-iron complex. Furthermore, the present inventors discovered that a "mushroom extract and trace element mixture" composed of a mixture of mushroom extract and trace elements also exhibits a more pronounced antibacterial effect than the plant extract and trace element mixture. Based on these findings, the present disclosure was completed.

[0019] That is, the present disclosure provides a hydroponic cultivation method characterized by adding a polyphenol-containing plant extract or a mushroom extract to a culture solution.

[0020] In the hydroponic cultivation method, when adding the polyphenol-containing plant extract or mushroom extract to the culture solution, the polyphenol-containing plant extract or mushroom extract and the trace elements may be mixed in the presence of water to obtain a plant extract / trace element mixture or a mushroom extract / trace element mixture, and then the plant extract / trace element mixture or the mushroom extract / trace element mixture may be added to the culture solution.

[0021] The culture medium may also contain a complex of a polyphenol-containing plant or mushroom extract (hereinafter sometimes referred to as "plant or mushroom extract") and the trace elements.

[0022] The trace elements may also contain at least boron, manganese, zinc, copper, molybdenum, and iron.

[0023] The polyphenol-containing plant may be one or more parts selected from the group consisting of grapes, coffee plants, tea plants, cacao, acacia, cedar, pine, citrus fruits, herbs, Houttuynia cordata, marigold, sugarcane, mango, banana, papaya, avocado, apple, cherry, guava, olive, potato, persimmon, mulberry, blueberry, poplar, ginkgo, chrysanthemum, sunflower, bamboo, radish, mustard, and eucalyptus, including leaves, stems, roots, fruits, seeds, husks, buds, flowers, and rhizomes.

[0024] The mushroom may also be one or more parts of mycelium, fruiting bodies, and waste mushroom beds of one or more mushrooms selected from the group consisting of Maitake mushroom, Shiitake mushroom, Enokitake mushroom, Bunashimeji mushroom, Honshimeji mushroom, Nameko mushroom, Pleurotus ostreatus, mushroom, Matsutake mushroom, and Pleurotus eryngii.

[0025] The hydroponic cultivation method may be a method of cultivating only Asteraceae or Lamiaceae plants, or a method of cultivating Asteraceae or Lamiaceae plants in a mixed planting with other plants, or a method of cultivating Asteraceae plants in a mixed planting with Lamiaceae plants.

[0026] The mixed cultivation may also be such that two or more types of plants are cultivated in different hydroponic cultivation areas, and the culture solution is circulated between these hydroponic cultivation areas.

[0027] The mixed cultivation may also be cultivation of two or more types of plants in the same hydroponic cultivation area.

[0028] Furthermore, the "Asteraceae plant" may be one or more plants selected from chrysanthemum, aster, sunflower, calendula, garland chrysanthemum, marigold, cosmos, peonies, dahlia, zinnia, margaret, dimorphotheca, cornflower, blue thistle, burdock, safflower, artichoke, lettuce, and salad greens, and the "Labiatae plant" may be one or more plants selected from shiso, perilla, basil, mint, hyssop, rosemary, lavender, sage, marjoram, oregano, thyme, lemon balm, salvia, barberry, ajuga, Chinese artichoke, and horsetail.

[0029] The hydroponic cultivation method may be such that the culture solution is not replaced, the pH of the culture solution is not adjusted, and a solid culture medium is not used. [Effects of the Invention]

[0030] In the present disclosure, by adding a polyphenol-containing plant or mushroom extract to a culture solution, the plant or mushroom extract is contained in the culture solution as a complex with trace elements, so that even if the composition balance of the culture solution is disrupted and the pH of the culture solution deviates from the optimal range, the trace elements can be prevented from converting to a form that is not absorbed by the plant and precipitating, thereby suppressing growth disorders caused by trace element deficiency and improving fertilizer utilization. Therefore, even in fully recirculating hydroponic cultivation, there is no need to adjust the pH of the culture solution, preventing material loss and enabling cost and labor savings in hydroponic cultivation.

[0031] Furthermore, according to the present disclosure, solid media such as coco peat and rock wool, which have traditionally been required for some crops, are no longer necessary, thereby solving the problems of their disposal and the problem of pathogenic microorganisms being carried in by adhering to solid media.

[0032] In addition, polyphenol-iron complexes, which are reaction products of polyphenols contained in plant or mushroom extracts with iron (a type of trace element), have strong bactericidal activity, organic substance decomposition activity, and ferrous ion supply activity. Furthermore, copper, zinc, molybdenum, and boric acid, which are types of trace elements, are also known to have antibacterial activity. Therefore, complexes of plant or mushroom extracts and trace elements exhibit more pronounced antibacterial activity than polyphenol-iron complexes.

[0033] In the present disclosure, the complex of this plant or mushroom extract and trace elements is contained in the culture solution, which enables efficient sterilization or inhibition of the growth of pathogenic microorganisms, and allows stable crop production without the need for closed environments to prevent the invasion of pathogenic microorganisms or sterilization using ultraviolet light, ozone, etc.

[0034] Furthermore, the organic substance decomposition (oxidative decomposition) action of polyphenol-iron complexes makes it possible to decompose and remove allelopathic substances exuded from plant roots, and therefore this disclosure can also prevent growth disorders caused by autointoxication.

[0035] Thus, according to the present disclosure, by simply adding polyphenol-containing plant or mushroom extracts to a culture solution, stable crop production is possible, despite the absence of a closed environment like a plant factory, detailed management of the nutrient solution environment, or the use of solid culture media, and furthermore, extremely economical, labor-saving, and environmentally friendly hydroponic cultivation can be realized, with absolutely no culture solution being wasted. [Brief explanation of the drawings]

[0036] [Figure 1] FIG. 1 is a schematic diagram illustrating a fertilization pattern for a plant. [Figure 2]FIG. 1 is a schematic diagram illustrating an example of an embodiment of mixed cultivation of a plant of the Asteraceae or Lamiaceae family with another plant. [Figure 3] FIG. 1 is a schematic diagram illustrating an example of an embodiment of mixed cultivation of a plant of the Asteraceae or Lamiaceae family with another plant. [Figure 4] 1 is a photographic image showing a test of bacterial wilt suppression in mixed cultivation of lisianthus and aster using an acacia extract (Test Example 2). The left shows monoculture, and the right shows mixed cultivation. [Figure 5] 1 is a graph showing the results of a test to suppress bacterial wilt disease when acacia extract is used to cultivate a mixed planting of lisianthus and aster (Test Example 2). In the figure, the vertical axis indicates the number of dead plants, the horizontal axis indicates the number of days since the start of cultivation, ▲ indicates the monoculture treatment area, and ◯ indicates the mixed planting treatment area. [Figure 6] FIG. 1 is a photographic image showing a hydroponic cultivation test of lettuce using culture solutions with different tea extract concentrations (Test Example 3). [Figure 7] 1 is a graph showing the effect of adding tea extract at different concentrations on the chlorophyll content (SPAD value) of lettuce (Test Example 3). In the figure, the vertical axis represents the SPAD value of the leaves, the horizontal axis represents the treatment group, and the bars represent the standard deviation. [Figure 8] FIG. 1 is a photographic image showing mixed planting of chrysanthemums using acacia extract (Example 1). [Figure 9] FIG. 2 is a photographic image showing the mixed cultivation of lisianthus and aster using a tea extract (Example 2). [Figure 10] FIG. 1 is a photographic image showing the mixed cultivation of statice and cornflower using coffee extract (Example 3). [Figure 11] FIG. 1 is a photographic image showing hydroponic cultivation of lisianthus using coffee extract (Example 4). [Figure 12] FIG. 1 is a photographic image showing hydroponic cultivation of blue thistle using a tea extract (Example 5). [Figure 13] FIG. 1 is a schematic diagram showing a hydroponic cultivation apparatus for lilies (Example 6). [Figure 14]FIG. 1 is a photographic image showing the hydroponic cultivation of lilies using various plant extracts (Example 6). [Figure 15] FIG. 10 is a diagram illustrating the measurement of the diameter of a lily flower (Example 6). [Figure 16] 1 is a graph showing the effect of adding various plant extracts on lily flowers (Example 6). In the figure, the vertical axis represents flower diameter (cm), the horizontal axis represents treatment groups, and the bars represent standard deviation. [Figure 17] FIG. 1 is a photographic image showing hydroponic cultivation of paprika using chrysanthemum extract, bamboo extract, and grape extract (Example 7). [Figure 18] FIG. 1 is a photographic image showing the appearance of paprika fruits produced by hydroponic cultivation using a plant extract (Example 7). [Figure 19] FIG. 1 is a photographic image showing hydroponic cultivation of strawberries using banana extract and sweet potato extract (Example 8). [Figure 20] FIG. 1 is a schematic diagram showing a hydroponic cultivation apparatus for strawberries (Example 9). [Figure 21] 1 is a photographic image showing the state of hydroponic cultivation of strawberries using various plant extracts (79 days after planting) (Example 9). The top shows the control group, and the bottom shows the group with cedar extract added. [Figure 22] 1 is a graph showing the effect of adding various plant extracts on the chlorophyll content (SPAD value) of strawberries (Example 9). In the figure, the vertical axis shows the SPAD value, the horizontal axis shows the treatment group, the bars show the standard deviation, and different letters indicate significant differences at the 5% significance level. [Figure 23] 1 is a graph showing the effect of adding various plant extracts on strawberry yield (Example 9). In the figure, the vertical axis represents total fruit weight (g), the horizontal axis represents treatment groups, the bars represent standard deviations, and different letters indicate significant differences at a significance level of 5% (n=3). [Figure 24] FIG. 1 is a schematic diagram showing a hydroponic cultivation apparatus for radish and Dimorphotheca (Asteraceae plants) (Example 10). [Figure 25] FIG. 1 is a photographic image showing the mixed cultivation of radish and Dimorphotheca (Asteraceae plant) using a cedar extract (Example 10). [Figure 26] 1 is a graph showing the effect of adding cedar extract on the yield of radish (Example 10). The vertical axis represents the yield of radish (fresh weight (g)), the horizontal axis represents the treatment group, the bars represent the standard deviation, and different letters indicate significant differences at the 5% significance level. [Figure 27] FIG. 11 is a schematic diagram (plan view) showing a hydroponic cultivation apparatus for radish and lettuce (Example 11). [Figure 28] FIG. 1 is a schematic diagram (side view) showing a hydroponic cultivation apparatus for radish and lettuce (Example 11). [Figure 29] FIG. 1 is a photographic image showing the mixed cultivation of radish and lettuce using various plant extracts (30 days after sowing) (Example 11). [Figure 30] 11 is a graph showing the effect of adding various plant extracts on the yield of radish (Example 11). In the figure, (a) shows the results for red radish and (b) shows the results for white radish. The vertical axis represents the fresh weight (g) per plant, the horizontal axis represents the treatment group, the bars represent the standard deviation, and different letters indicate significant differences at a significance level of 5% (n=9). [Figure 31] 12 is a photographic image showing the state of hydroponic cultivation of perilla using rosemary extract and oregano extract (21 days after planting) (Example 12). In the figure, (a) shows the control group, (b) shows the oregano extract group, and (c) shows the rosemary extract group. [Figure 32] 1 is a graph showing the effect of adding rosemary extract and oregano extract on the growth of perilla (Example 12). In the figure, the vertical axis represents plant height (cm), the horizontal axis represents treatment groups, the bars represent standard deviation, and different letters indicate significant differences at the 5% significance level (n=18). [Figure 33] 13 is a photograph showing the mixed cultivation of perilla and spinach using rosemary extract and oregano extract (Example 13), where (a) shows the control group, (b) shows the oregano extract group, and (c) shows the rosemary extract group. [Figure 34]13 is a graph showing the effect of adding rosemary extract and oregano extract on the growth of perilla and spinach (21 days after planting) (Example 13). In the figure, (a) shows the measurement results for perilla plant height, and (b) shows the chlorophyll content of spinach leaves. In (a), the vertical axis is plant height (cm), the horizontal axis is treatment group, the bars indicate standard deviation, and different letters indicate significant differences at the 5% significance level (n=18). In (b), the vertical axis is leaf chlorophyll content (SPAD value), the horizontal axis is treatment group, the bars indicate standard deviation, and different letters indicate significant differences at the 5% significance level (n=18). [Figure 35] FIG. 1 is a schematic diagram illustrating a method for evaluating the antibacterial effect of various plant extract trace element complexes (Test Example 4). [Figure 36] Photographs showing the antibacterial effect of various plant extract trace element complexes (Test Example 4). (a) shows the control, (b) shows the acacia extract trace element complex, (c) shows the grape extract trace element complex, (d) shows the poplar extract trace element complex, (e) shows the lemon balm extract trace element complex, and (f) shows the banana extract trace element complex. [Figure 37] Photographs showing the antibacterial effect of various plant extract trace element complexes (Test Example 4). (g) shows the ginkgo extract trace element complex group, (h) shows the cacao extract trace element complex group, (i) shows the cedar extract trace element complex group, (k) shows the pine extract trace element complex group, (m) shows the perilla extract trace element complex group, and (n) shows the yuzu extract trace element complex group. [Figure 38] Photographs showing the antibacterial effects of various plant extract trace element complexes (Test Example 4). (o) indicates the coffee extract trace element complex group, (p) indicates the persimmon extract trace element complex group, (q) indicates the oregano extract trace element complex group, (r) indicates the mustard extract trace element complex group, (s) indicates the chrysanthemum extract trace element complex group, and (t) indicates the guava extract trace element complex group. [Figure 39]Photographs showing the antibacterial effect of various plant extract trace element complexes (Test Example 4). (u) indicates the mulberry extract trace element complex group, (v) indicates the sweet potato extract trace element complex group, (w) indicates the sage extract trace element complex group, (x) indicates the radish extract trace element complex group, (y) indicates the bamboo leaf extract trace element complex group, and (z) indicates the bamboo bark extract trace element complex group. [Figure 40] Photographs showing the antibacterial effect of various plant extract trace element complexes (Test Example 4). (a') shows the papaya extract trace element complex group, (b') the cypress bark extract trace element complex group, (c') the cypress leaf extract trace element complex group, (d') the peppermint extract trace element complex group, (e') the mango extract trace element complex group, and (f') the mandarin orange extract trace element complex group. [Figure 41] Photographs showing the antibacterial effect of various plant extract trace element complexes (Test Example 4). (g') shows the willow extract trace element complex group, (h') shows the eucalyptus extract trace element complex group, (i') shows the mugwort extract trace element complex group, (k') shows the lavender extract trace element complex group, (m') shows the rosemary extract trace element complex group, and (n') shows the lemon extract trace element complex group. [Figure 42] Photographs showing the antibacterial effect of various plant extract trace element complexes (Test Example 4). (o') shows the tea extract trace element complex group, and (p') shows the sugarcane extract trace element complex group. [Figure 43] Photographs showing the antibacterial effect of chrysanthemum roots and a polyphenol-iron complex (Test Example 5). (a) shows the area treated with chrysanthemum roots only (control), and (b) shows the area treated with chrysanthemum roots and a polyphenol-iron complex. [Figure 44] FIG. 1 is a schematic diagram illustrating a method for measuring antibacterial effects (Test Example 6). [Figure 45] FIG. 1 is a photographic image showing the mixed cultivation of basil and lettuce using oregano extract (Example 14). [Figure 46]1 is a graph showing the effect of oregano extract addition on the yield of (a) basil and (b) lettuce (Example 14). The vertical axis represents fresh weight (g) per plant, the horizontal axis represents treatment groups, the bars represent standard deviations, and different letters indicate significant differences at the 5% significance level (n=18). [Figure 47] FIG. 1 is a photographic image showing the mixed cultivation of basil and parsley using oregano extract (Example 14). [Figure 48] 1 is a graph showing the effect of oregano extract addition on the yield of (a) basil and (b) parsley (Example 14). The vertical axis represents fresh weight (g / plant), the horizontal axis represents treatments, and the bars represent standard deviations. Different letters indicate significant differences at the 5% significance level (n=18). [Figure 49] FIG. 1 is a photographic image showing the mixed cultivation of radish and oregano using rosemary extract (Example 15). [Figure 50] 1 is a graph showing the effect of adding rosemary extract on the yield of (a) radish and (b) oregano (Example 15). The vertical axis represents fresh weight (g / plant), the horizontal axis represents treatment, the bars represent standard deviation, and different letters indicate significant differences at the 5% significance level (n=9). [Figure 51] FIG. 1 is a photographic image showing the mixed cultivation of radish and rosemary using rosemary extract (Example 15). [Figure 52] 1 is a graph showing the effect of adding rosemary extract on the yield of (a) radish and (b) rosemary (Example 15). The vertical axis represents fresh weight (g / plant), the horizontal axis represents treatment groups, the bars represent standard deviations, and different letters indicate significant differences at the 5% significance level (n=9). [Figure 53] FIG. 1 is a photographic image showing the mixed cultivation of radish and lemon balm using rosemary extract (Example 15). [Figure 54]1 is a graph showing the effect of adding rosemary extract on the yield of (a) radish and (b) lemon balm (Example 15). The vertical axis represents fresh weight (g / plant), the horizontal axis represents treatment, the bars represent standard deviation, and different letters indicate significant differences at the 5% significance level (n=9). [Figure 55] FIG. 1 is a photographic image showing the mixed cultivation of radish and mojito mint using thyme extract (Example 15). [Figure 56] 1 is a graph showing the effect of thyme extract addition on the yield of (a) daikon radish and (b) mojito mint (Example 15). The vertical axis represents fresh weight (g / plant), the horizontal axis represents treatment, the bars represent standard deviation, and different letters indicate significant differences at the 5% significance level (n=9). [Figure 57] 16 is a schematic diagram (cross-sectional view) showing a hydroponic cultivation apparatus for tomatoes and basil or chrysanthemums (Example 16). (a) shows a tomato-only cultivation area, (b) shows a tomato-basil mixed cultivation area, and (c) shows a tomato-chrysanthemum mixed cultivation area. [Figure 58] Photographs showing the appearance of mixed cultivation of tomatoes and basil or chrysanthemums (at the time of planting) (Example 16). (a) shows a tomato-only cultivation area, (b) shows a tomato-basil mixed cultivation area, and (c) shows a tomato-chrysanthemum mixed cultivation area. [Figure 59] 16 is a photographic image showing the state of mixed cultivation of tomato with basil or chrysanthemum (52 ​​days after planting) and the effect on the density of contaminating bacteria in the culture solution (Example 16). (a) shows the tomato-only cultivation area, (b) shows the tomato-basil mixed cultivation area, and (c) shows the tomato-chrysanthemum mixed cultivation area. [Figure 60] 16 is a graph showing the effects of interplanting with basil or chrysanthemum on (a) total fresh weight and (b) fruit yield of tomatoes (Example 16). In (a), the vertical axis is total fresh weight (kg / plant), the horizontal axis is treatment, the bars indicate standard deviation, and different letters indicate significant differences at the 5% significance level (n=3). In (b), the vertical axis is fruit yield (kg / m2), the horizontal axis is treatment, the bars indicate standard deviation, and different letters indicate significant differences at the 5% significance level (n=3). [Figure 61]Photographs showing the antibacterial effect of various plant extract trace element complexes (Test Example 9). (a) shows the control group (no plant extract added), (b) shows the lily extract trace element complex group, (c) shows the apple mint extract trace element complex group, (d) shows the basil extract trace element complex group, (e) shows the aromaticus extract trace element complex group, and (f) shows the loquat extract trace element complex group. [Figure 62] Photographs showing the antibacterial effect of various plant extract trace element complexes (Test Example 9). (g) shows the Houttuynia cordata extract trace element complex group, (h) shows the eggplant extract trace element complex group, (i) shows the hibiscus extract trace element complex group, (k) shows the tomato extract trace element complex group, (m) shows the chili pepper extract trace element complex group, and (n) shows the cassava extract trace element complex group. [Figure 63] Photographs showing the antibacterial effects of various plant extract trace element complexes (Test Example 9). (o) indicates the lady plymouth geranium extract trace element complex group, (p) indicates the Japanese honeywort extract trace element complex group, (q) indicates the purple basil extract trace element complex group, (r) indicates the oregano extract trace element complex group, (s) indicates the coriander extract trace element complex group, and (t) indicates the passion fruit extract trace element complex group. [Figure 64] Photographs showing the antibacterial effects of various plant extract trace element complexes (Test Example 9). (u) indicates the pink pepper extract trace element complex group, (v) indicates the plum extract trace element complex group, (w) indicates the rhubarb extract trace element complex group, (x) indicates the arugula extract trace element complex group, (y) indicates the rose extract trace element complex group, and (z) indicates the pennyroyal mint extract trace element complex group. [Figure 65] Photographs showing the antibacterial effect of various plant extract trace element complexes (Test Example 9). (a') shows the cherry blossom extract trace element complex group, (b') the soybean extract trace element complex group, (c') the chive leaf extract trace element complex group, (d') the horsetail extract trace element complex group, (e') the Akebia extract trace element complex group, and (f') the thyme extract trace element complex group. [Figure 66]Photographs showing the antibacterial effect of various plant extract trace element complexes (Test Example 9). (g') shows the Solidago altissima extract trace element complex group, (h') shows the perilla extract trace element complex group, (i') shows the goldenrod extract trace element complex group, (k') shows the camphor tree extract trace element complex group, (m') shows the clove extract trace element complex group, and (n') shows the bamboo grass extract trace element complex group. [Figure 67] Photographs showing the antibacterial effect of various plant extract trace element complexes (Test Example 9). (o') represents the cinnamon extract trace element complex group, (p') represents the sweet vernal grass extract trace element complex group, (q') represents the lettuce extract trace element complex group, (r') represents the paprika extract trace element complex group, (s') represents the eucalyptus extract trace element complex group, and (t') represents the bell pepper extract trace element complex group. [Figure 68] Photographs showing the antibacterial effect of a mixture of various plant extracts and trace elements (Test Example 10). (a) shows plant extracts from fleabane annuus, and (b) shows plant extracts from chamomile, trace elements, and their reaction products (plant extract-trace element complex). [Figure 69] Photographs showing the antibacterial effect of a mixture of various plant extracts and trace elements (Test Example 10). (a) shows plant extracts from rhubarb, and (b) shows plant extracts from cassava, trace elements, and their reaction products (plant extract-trace element complex). [Figure 70] Photographs showing the antibacterial effect of a mixture of various plant extracts and trace elements (Test Example 10). (a) shows plant extracts, trace elements, and their reaction products (plant extract-trace element complex) from Houttuynia cordata and (b) from coriander. [Figure 71] Photographs showing the antibacterial effect of a mixture of various plant extracts and trace elements (Test Example 10). (a) shows Swiss chard plant extract, (b) shows Aralia aralia bud plant extract, trace elements, and their reaction product (plant extract-trace element complex). [Figure 72] 10 is a photographic image showing the antibacterial effect of a mixture of various plant extracts and trace elements (Test Example 10). (a) shows plant extracts from kudzu and (b) shows plant extracts from cinnamon, trace elements, and their reaction products (plant extract-trace element complex). [Figure 73] Photographs showing the antibacterial effect of the mushroom extract trace element complex (Test Example 11). (a) shows the control group (no mushroom extract added), (b) shows the Maitake extract trace element complex group, and (c) shows the Shiitake extract trace element complex group. DETAILED DESCRIPTION OF THE INVENTION

[0037] The hydroponic cultivation method of this embodiment will be described in detail below. The hydroponic cultivation method of this embodiment is a hydroponic cultivation method in which an extract of a polyphenol-containing plant or mushroom is added to a culture solution.

[0038] The term "polyphenol-containing plant" refers to a plant containing polyphenols or a processed product thereof. Here, the "plant" may include one or more parts selected from the fruit, seeds, stems, leaves, outer skin, buds, flowers, roots, and rhizomes of the plant.

[0039] Examples of "polyphenol-containing plants" include herbs (lavender, mint, coriander, cumin, sage, lemongrass, mugwort, comfrey, shiso, lemon balm, oregano, catnip, common thyme, dill, dark opal, basil, hyssop, peppermint, lamb's ear, etc.), Houttuynia cordata, marigold, grapes, coffee (Coffea abies), tea (Camellia sinensis), cacao, acacia, cedar, pine, sugarcane, mango, banana, papaya, avocado, apple, cherry, guava, olive, potatoes (sweet potato, Purple sweet potato (sweet potato with a high purple pigment content), potato, yam, taro (coroaming potato, shrimp potato, etc.), konjac, etc.), persimmon, mulberry, blueberry, poplar, ginkgo, chrysanthemum, sunflower, bamboo, citrus fruits (lemon, lime, orange, grapefruit, navel orange, yuzu, kumquat, kabosu, summer mandarin, hassaku, iyokan, lime, Satsuma mandarin, Shikuwasa, mandarin, etc.), radish, mustard, eucalyptus, strawberry, blackberry, cranberry, raspberry, bilberry, huckleberry, plum, peach, plum, pear, western Pear, loquat, kiwi fruit, mangosteen, shishito pepper, prune, melon, dragon fruit, wolfberry, black currant, cashew, viburnum, pomegranate, acai, aronia, eggplant, tomato, soybean, black soybean, adzuki bean, green bean, peanut, black sesame, buckwheat, tartary buckwheat, sesame, purple cabbage, sumac, water chestnut, crown chrysanthemum, broccoli, spinach, komatsuna, mitsuba, okra, butterbur, onion, mulukhiyah, crown chrysanthemum, garlic, purple onion, asparagus, parsley, udo, Gymnema sylvestre, senna, dandelion, horsetail, fern (bracken, fern), etc. ), oak, sawtooth oak, maple, sequoia, metasequoia, cypress, Mallotus japonicus, Takanotsume, Amacha, Akebia, Japanese angelica, Cleistocene, Amur magnolia, Magnolia magnolia, Aralia arbutifolia, White syrup, Kuromoji, Koshiabura, Clerodendron obovata, Magnolia obovata, Actinidia chinensis, Banaba, Rooibos, Rahma, Kudzu, Japanese laurel, Lithospermum japonica, Brassica rapa, Melinjo, cherry blossom, Magnolia, Yerba mate, Kandelia candel, Bruguiera gigantea, Rhizophora gracilis, Sea pomegranate, Nipa palm, Avicennia marina, Mangrove, Heronia japonica, Burdock, Turmeric, Lotus root, Seaweed (Nori,Examples include wakame seaweed, kelp, sea lettuce, Eisenia bicolor, and Sagarame seaweed.

[0040] Among them are grapes, coffee (coffee tree), tea (camellia), cacao, acacia, cedar, pine, citrus fruits, herbs (lavender, mint, coriander, cumin, sage, shiso, lemongrass, mugwort, comfrey, lemon balm, oregano, catnip, common thyme, dill, dark opal, basil, hyssop, peppermint, lamb's ear, etc.), Houttuynia cordata, marigold, and sato. Suitable fruits for use include water saplings, mangoes, bananas, papayas, avocados, apples, cherries, guavas, olives, potatoes (sweet potatoes, purple potatoes (sweet potatoes containing a lot of purple pigment), potatoes, yams, taro (cories, shrimp potatoes, etc.), konjac potatoes, etc.), persimmons, mulberries, blueberries, poplars, ginkgo trees, chrysanthemums, sunflowers, bamboo, radishes, mustard greens, and eucalyptus.

[0041] Furthermore, the "processed product" of a polyphenol-containing plant is not particularly limited. Specific examples include tea leaves, roasted coffee beans, and ground coffee beans. Extraction residues and pomace of polyphenol-containing plants are also included in the "processed product." Specific examples include so-called coffee grounds, used tea leaves, and wine dregs. These are rich in polyphenols and, because they are waste products, the raw material costs can be kept low, making them suitable as raw materials for polyphenol extraction.

[0042] As for "tea leaves," any kind of tea leaves picked from the stems of the tea plant can be used. Specific examples include green tea (sencha, bancha, kukicha, hojicha, etc.), green tea (oolong tea, etc.), black tea, and dark tea (pu-erh tea, etc.). Of these, green tea, black tea, and oolong tea are preferred.

[0043] The polyphenol-containing plants may be used alone or in combination of two or more species.

[0044] "Mushrooms" generally refer to fungi that form fruiting bodies and produce spores in the fruiting bodies. Most mushrooms belong to the phylum Basidiomycota or Ascomycota. As used herein, "mushrooms" may be those containing polyphenols. From the standpoint of safety, it is preferable to use one or more parts selected from the mycelium, fruiting body, and waste mushroom bed of edible mushrooms. Processed products such as dried or crushed mushrooms may also be used.

[0045] Examples of edible mushrooms include maitake mushroom, shiitake mushroom, enokitake mushroom, buna-shimeji mushroom, hon-shimeji mushroom, nameko mushroom, oyster mushroom, mushroom, matsutake mushroom, king oyster mushroom, aitake mushroom, morel mushroom, amitake mushroom, wood ear mushroom, wood ear mushroom, abalone mushroom, chanterelle mushroom, imotake mushroom, urabenihoteishimeji mushroom, astragalus mushroom, onifusa mushroom, kanzo-take mushroom, wood ear mushroom, kishimachimeji mushroom, kitsunetake mushroom, kinugasatake mushroom, knotweed mushroom, konomitake mushroom, saketubatake mushroom, shibafutake mushroom, shogenji mushroom, camphor mushroom, white onion mushroom, Examples include agaric, white mushroom, white fungus, Japanese oyster mushroom, stinkhorn mushroom, common camphor mushroom, egg mushroom, egg jelly, egg mushroom, Tamogitake mushroom, milk mushroom, false tea mushroom, cordyceps, Tsukuritake mushroom, Armillaria mellea, slimy bolete, Noboriryu, Venus shiitake mushroom, Bakamatsutake mushroom, Hatakeshimeji mushroom, Hanaiguchi mushroom, agaric, Haru shiitake mushroom, Straw mushroom, Beech matsutake mushroom, Red matsutake mushroom, Mukitake mushroom, Purple shiitake mushroom, Boletus edodes, false boletus, Yamabushitake mushroom, and Yukiwari mushroom.

[0046] Among these, maitake mushroom, shiitake mushroom, enoki mushroom, buna-shimeji mushroom, hon-shimeji mushroom, nameko mushroom, oyster mushroom, mushroom, matsutake mushroom, and king oyster mushroom are preferably used. Only one type of the above mushrooms may be used, or two or more types may be mixed and used.

[0047] The "extract" of a polyphenol-containing plant or mushroom can be an extract or extract obtained by extracting a polyphenol-containing plant or mushroom with an appropriate extraction solvent, or a dried or purified product thereof. Furthermore, the squeezed juice of a polyphenol-containing plant or mushroom, as well as its concentrate, dried product, purified product, etc., are also included in the "extract" because they contain components equivalent to those of an extract.

[0048] Suitable "extraction solvents" include, but are not limited to, water, hot water, alcohol (particularly ethanol), aqueous alcohol (particularly aqueous ethanol), and petroleum ether.

[0049] The "dried material" is preferably one that has been crushed, pulverized, powdered, etc. Furthermore, in terms of reaction efficiency with trace elements, a powder with a small particle size is preferred.

[0050] "Polyphenols" is a general term for phenolic molecules with multiple hydroxyl groups. They are compounds found in most plants, and various types are known, including flavonoids and phenolic acids.

[0051] Specific examples of compounds include catechins (epicatechin, epigallocatechin, epicatechin gallate, epigallocatechin gallate, etc.), tannic acid, tannins, chlorogenic acid, caffeic acid, neochlorogenic acid, cyanidin, proanthocyanidin, thearubigin, rutin, flavonoids (quercitrin, anthocyanins, flavanones, flavanols, flavonols, isoflavones, etc.), flavones, chalcones (naringenin chalcone, etc.), xanthophyll, carnosic acid, eriocitrin, nobiletin, tangeretin, magnolol, honokiol, ellagic acid, lignans, curcumin, coumarin, catechol, procyanidins, theaflavin, rosmarinic acid, xanthone, quercetin, resveratrol, gallic acid, and phlorotannin. Further examples include compounds having one or more of these compounds in the molecule (for example, polymerized complexes containing these compounds bound together).

[0052] The "polyphenols" in the present embodiment may be only one of the above-mentioned compounds, or may be a composition consisting of two or more of them.

[0053] Polyphenol compositions extracted from a certain plant may also be referred to as polyphenols, with the name of the plant attached. For example, polyphenols extracted from grapes are called grape polyphenols.

[0054] The "nutrient solution" can be a commercially available liquid fertilizer for hydroponic cultivation diluted appropriately depending on the type of crop. Such a nutrient solution contains macronutrients and trace elements necessary for crop growth.

[0055] Examples of "trace elements" include boron, manganese, zinc, copper, molybdenum, and iron. In particular, those containing at least iron are preferred, a combination of two or more elements containing iron is more preferred, and those containing all of these are even more preferred.

[0056] Generally, polyphenols form complexes with the trace elements, and therefore, it is believed that the polyphenols contained in the extract of the polyphenol-containing plant added to the culture medium are contained in the culture medium as complexes with the trace elements.

[0057] In addition, most plants and mushrooms contain organic acids, sugars, etc. in addition to polyphenols, which may also react with trace elements to form complexes. Therefore, the culture solution may contain complexes of trace elements with organic acids, sugars, etc. contained in polyphenol-containing plant or mushroom extracts, in addition to complexes of polyphenols and trace elements. Therefore, in this embodiment, the term "plant or mushroom extract trace element complex" includes not only polyphenols but also complexes of trace elements with all compounds contained in plant or mushroom extracts.

[0058] Examples of complexes of polyphenols with the trace elements include polyphenol-iron complexes, polyphenol-boron complexes, polyphenol-manganese complexes, polyphenol-zinc complexes, polyphenol-copper complexes, and polyphenol-molybdenum complexes.

[0059] The term "polyphenol-iron complex" refers to a reaction product obtained by mixing polyphenols or their source materials with iron source materials in the presence of water, as described in the above-mentioned Patent Documents 3 to 9, and contains divalent iron ions (Fe 2+ ) forms a complex structure with polyphenols. This polyphenol-iron complex functions as a Fenton reaction catalyst and a visible light-responsive photocatalyst, and has excellent bactericidal properties, organic substance decomposition properties, and ferrous ion supply properties.

[0060] In this embodiment, the polyphenol-containing plant or mushroom extract may be added to the culture solution by directly adding the polyphenol-containing plant or mushroom extract to the culture solution in which the plant roots are soaked.Another method involves preliminarily mixing the polyphenol-containing plant or mushroom extract with the trace elements in the presence of water to obtain a "plant or mushroom extract / trace element mixture," and then adding the plant or mushroom extract / trace element mixture to the culture solution.

[0061] It has been known that high molecular weight polyphenols such as tannins cause physiological disorders in plants (such as inhibition of root elongation). Therefore, in the present embodiment, too, the addition of a polyphenol-containing plant or mushroom extract to the culture solution may cause physiological disorders in plants.

[0062] Therefore, it is preferable to adopt the latter method, in which polyphenols are reacted with trace elements in advance to form complexes, thereby saturating the polyphenols and adding them to the culture solution (i.e., a method in which the polyphenol-containing plant or mushroom extract and the trace elements are mixed in the presence of water to obtain a plant or mushroom extract-trace element mixture, and then the plant or mushroom extract-trace element mixture is added to the culture solution).

[0063] When preparing a culture solution before starting hydroponic cultivation, the polyphenol-containing plant or mushroom extract may be added directly to the culture solution.

[0064] The step of preparing the "plant or mushroom extract trace element mixture" can be carried out by mixing the polyphenol-containing plant or mushroom extract and the trace elements in the presence of water.

[0065] The "trace elements" to be mixed with the polyphenol-containing plant or mushroom extract may contain at least one element selected from the group consisting of boron, manganese, zinc, copper, molybdenum, and iron, and preferably two or more elements including iron. Commercially available liquid fertilizers for hydroponic cultivation are suitable for use because they contain these trace elements in a composition suitable for crop growth.

[0066] The mixing ratio of the polyphenol-containing plant or mushroom extract to the trace elements can be calculated as the weight ratio of each element constituting the trace elements to 100 parts by weight of the dry weight of the polyphenol-containing plant or mushroom used as the extraction raw material.

[0067] For example, if dried tea leaves are used as the polyphenol-containing plant material, and the tea leaves are extracted with hot water to obtain an extract, and the trace elements are reacted with the extract, the weight of the dried tea leaves can be used as the "dry weight of the polyphenol-containing plant material or mushroom" to calculate the mixing ratio with the trace elements.

[0068] The desirable weight conversion ratio of each element constituting the trace elements to 100 parts by weight of the dry weight of the polyphenol-containing plant or mushroom can be, for example, as follows.

[0069] Iron: 0.1 parts by weight or more and 1000 parts by weight or less, preferably 1 part by weight or more and 800 parts by weight or less, more preferably 4 parts by weight or more and 500 parts by weight or less, even more preferably 10 parts by weight or more and 300 parts by weight or less, and particularly preferably 20 parts by weight or more and 100 parts by weight or less.

[0070] Boron: 0.01 to 100 parts by weight, preferably 0.1 to 80 parts by weight, more preferably 0.4 to 50 parts by weight, and even more preferably 1 to 30 parts by weight.

[0071] Manganese: 0.01 part by weight or more and 100 parts by weight or less, preferably 0.1 part by weight or more and 80 parts by weight or less, more preferably 0.4 part by weight or more and 50 parts by weight or less, and even more preferably 1 part by weight or more and 30 parts by weight or less.

[0072] Zinc: 0.001 to 10 parts by weight, preferably 0.01 to 8 parts by weight, more preferably 0.04 to 5 parts by weight, and even more preferably 0.1 to 3 parts by weight.

[0073] Copper: 0.0002 parts by weight or more and 2 parts by weight or less, preferably 0.002 parts by weight or more and 1.6 parts by weight or less, more preferably 0.008 parts by weight or more and 1 part by weight or less, and even more preferably 0.02 parts by weight or more and 0.6 parts by weight or less.

[0074] Molybdenum: 0.00004 parts by weight or more and 0.4 parts by weight or less, preferably 0.0005 parts by weight or more and 0.3 parts by weight or less, more preferably 0.0016 parts by weight or more and 0.2 parts by weight or less, and even more preferably 0.004 parts by weight or more and 0.12 parts by weight or less.

[0075] If the proportion of the trace elements is too low below the above range (if the proportion of the polyphenol-containing plant or mushroom extract is too high relative to the trace elements), the excess polyphenols will function as radical scavengers, which may inhibit the Fenton reaction or photocatalytic reaction caused by the polyphenol-iron complex.

[0076] Furthermore, if the proportion of the trace elements is higher than the above range (if the mixing ratio of the polyphenol-containing plant or mushroom extract is too low relative to the trace elements), it is not preferable because the trace elements cannot be maintained in a state that makes them easily absorbed by plant roots.

[0077] The above-mentioned mixing ratio of the polyphenol-containing plant or mushroom extract and the trace elements can also be applied when the polyphenol-containing plant or mushroom extract is added directly to the culture solution.

[0078] The polyphenol-containing plant or mushroom extract and the trace elements are mixed in the presence of water. Here, "in the presence of water" refers to conditions under which the polyphenol-containing plant or mushroom extract and the trace elements can react with each other using water as a medium. Specifically, this reaction is presumed to be a reaction in which the polyphenol-containing plant or mushroom extract forms a complex with the trace elements.

[0079] The amount of water may be any amount that allows at least mixing and stirring of the polyphenol-containing plant or mushroom extract and the trace elements, and may be an amount that is sufficient to wet the mixture of the polyphenol-containing plant or mushroom extract and the trace elements.

[0080] When the polyphenol-containing plant or mushroom extract is a liquid such as a juice or extract of the plant or mushroom, or when a liquid fertilizer or aqueous solution is used as the trace elements, the two can be directly mixed and reacted without adding a new medium.

[0081] The mixing operation may be simple stirring and mixing using a stirrer or the like, but may also be carried out using a mixer, a large stirring tank, a vortex, a shaker, or the like.

[0082] The temperature of the water during mixing may be any temperature at which the water is in a liquid state (for example, 1 to 100°C at 1 atmospheric pressure). Although it is possible to use a temperature around room temperature (for example, 10 to 35°C) that does not require heating, if heating is required, heating to 40°C or higher, preferably 50°C or higher, is preferred as this promotes the production of the plant or mushroom extract trace element complex.

[0083] The upper limit of the water temperature during mixing can be 200°C (when heated under pressure), but from the viewpoint of production costs, it is desirable to carry out the reaction at 100°C or below, which is the boiling point when heated under normal pressure, preferably 90°C or below, and more preferably 70°C or below. Note that, under reaction conditions of 100°C or above, it is preferable to carry out the reaction in a sealed container in order to prevent thermal decomposition of the plant or mushroom extract.

[0084] The mixing time should be approximately 10 seconds or longer until the plant or mushroom extract and trace elements are in sufficient contact with each other. However, to improve uniformity, it is desirable to carry out the mixing process for preferably 1 minute or longer, more preferably 3 minutes or longer, and even more preferably 5 minutes or longer.

[0085] The upper limit of the mixing time is 10 days or less, preferably 7 days or less, more preferably 5 days or less, even more preferably 3 days or less, and particularly preferably 1 day or less, in order to prevent putrefaction of the organic matter due to proliferation of microorganisms. However, if sterilization treatment is involved, there is no particular upper limit.

[0086] The reaction product (a reaction product of plant or mushroom extract and trace elements) obtained through the above mixing treatment has excellent ferrous ion supply activity, Fenton reaction catalytic activity, and photocatalytic activity. It is presumed that the reaction product contains a plant or mushroom extract trace element complex containing a polyphenol-iron complex.

[0087] The above-described mixing process can prepare the "plant or mushroom extract trace element mixture" of this embodiment. Furthermore, the supernatant or precipitate obtained by centrifuging the above-described mixture, the dried product obtained by concentrating and drying these, and the suspension and supernatant thereof obtained by dissolving the dried product in water can also be used as the "plant or mushroom extract trace element mixture" of this embodiment.

[0088] The polyphenol-containing plant or mushroom extract is added by adding the thus obtained "plant or mushroom extract trace element mixture" to the culture solution. Specifically, the plant or mushroom extract trace element mixture may be added to a culture solution tank, a cultivation container, or the piping connecting these.

[0089] The plant or mushroom extract trace element mixture is preferably added at the start of cultivation and then periodically at intervals of one to three weeks.

[0090] The amount and concentration of the plant or mushroom extract trace element mixture to be added may be adjusted appropriately to provide an amount of trace elements appropriate for the type of crop and growth stage, similar to top dressing in conventional hydroponic or soil culture.

[0091] Specifically, changes in fertilizer utilization rates in plants can be broadly categorized into start-dash, constant, and last-minute spurt patterns, as shown in Figure 1. Constant-type crops are common among leafy vegetables, while last-minute spurt types are common among flowers and fruit vegetables. By adjusting the amount of polyphenol and trace element mixture added to the nutrient solution according to the fertilization pattern of each crop, the highest yield can be achieved.

[0092] In this case, if the amount of polyphenols is excessive, physiological disorders may occur in the plant roots. Therefore, when adding a large amount of plant or mushroom extract trace element mixture, it is necessary to add it in multiple doses while monitoring the condition of the roots.

[0093] By adding the polyphenol-containing plant or mushroom extract to the culture medium as described above, plant or mushroom extract trace element complexes, including polyphenol-iron complexes, are contained in the culture medium.

[0094] This means that even if the composition balance of the culture solution is disrupted as the plant grows and the pH of the culture solution falls outside the optimal range, the absorption of trace elements will not be hindered, making it possible to prevent growth disorders caused by trace element deficiencies.

[0095] Conventional hydroponic cultivation of fruit and vegetables requires a solid medium to absorb nutrients, but according to this embodiment, the roots can sufficiently absorb nutrients in the culture solution even without a solid medium, making a solid medium unnecessary.

[0096] Furthermore, the strong bactericidal action of the plant or mushroom extract trace element complex enables the sterilization of pathogenic microorganisms in the culture solution. Even if disease occurs in some crops, the bactericidal action suppresses the growth of pathogenic microorganisms, preventing the spread of damage to the entire hydroponic cultivation system. Therefore, crops can be produced stably even in a simple greenhouse, eliminating the need for sterilization using ultraviolet light, ozone, chemicals, etc.

[0097] Furthermore, the organic substance decomposition action of polyphenol-iron complexes makes it possible to decompose and remove allelopathic substances, thereby preventing growth disorders caused by autointoxication.

[0098] In this embodiment, in order to distribute the plant or mushroom extract trace element complex throughout the culture solution and achieve a high bactericidal effect, it is desirable to perform cultivation while generating a water current in the culture solution and stirring it. Examples of means for generating a water current or stirring include, but are not limited to, circulating the culture solution within the cultivation system using a pump, or generating a water current by supplying air or oxygen to the culture solution tank using an air pump.

[0099] In the hydroponic cultivation method according to the present embodiment, there are no particular limitations on the plants that can be cultivated, but agricultural crops such as vegetables, including leafy stem vegetables, fruit vegetables, and root vegetables, as well as flowers and grains are suitable.

[0100] The inventors of the present application have discovered that hydrogen peroxide is abundantly contained in the roots of plants of the Asteraceae and Lamiaceae families, and that hydrogen peroxide exudes from the roots. Because hydrogen peroxide is necessary for the Fenton reaction by polyphenol-iron complexes, it is believed that cultivating plants of the Asteraceae or Lamiaceae families in this embodiment will promote the Fenton reaction, thereby further enhancing the effects of disease control and the decomposition and removal of allelopathic substances.

[0101] Therefore, in this embodiment, it is desirable to cultivate a plant of the Asteraceae or Lamiaceae family alone, or a plant of the Asteraceae or Lamiaceae family mixed with other plants, or a plant of the Asteraceae family mixed with a plant of the Lamiaceae family.

[0102] Here, there are no particular limitations on the "Asteraceae plant", but examples include chrysanthemum, aster, sunflower, calendula, garland chrysanthemum, marigold, cosmos, larkspur, dahlia, zinnia, margaret, dimorphotheca, cornflower, blue thistle, burdock, safflower, artichoke, lettuce, and salad greens.

[0103] There are no particular limitations on "Labiatae plants", but examples include perilla, perilla, basil, mint, hyssop, rosemary, lavender, sage, marjoram, oregano, thyme, lemon balm, salvia, bark bean, ajuga, Chinese holly, and horsetail.

[0104] When only plants of the Asteraceae or Lamiaceae family are cultivated, only one species may be cultivated alone, two or more species of Asteraceae or Lamiaceae plants may be cultivated together, or one or more Asteraceae plants may be cultivated together with one or more Lamiaceae plants. When plants of the Asteraceae or Lamiaceae family are cultivated together with plants other than the Asteraceae or Lamiaceae family, one or more species of Asteraceae or Lamiaceae plants may be cultivated together with one or more plants other than the Asteraceae or Lamiaceae family, or one or more Asteraceae plants may be cultivated together with one or more Lamiaceae plants and one or more plants other than the Asteraceae or Lamiaceae family.

[0105] As an example of "mixed cultivation," as shown in Figure 2, two or more types of plants are cultivated in different hydroponic cultivation zones, and the nutrient solution is circulated between these hydroponic cultivation zones. Here, the "hydroponic cultivation zone" refers to the area where plants are cultivated hydroponically. For example, it is an area separated by an aquarium or container.

[0106] 2 shows an embodiment of mixed cultivation of plants of the Asteraceae or Lamiaceae family with other plants. The hydroponic cultivation system 1 is mainly composed of cultivation beds or houses A to E and pipes 21 and 22.

[0107] As shown in Figure 2, this embodiment includes both a form in which a hydroponic cultivation system 1 is constructed by connecting multiple cultivation beds in a single greenhouse, and a form in which a large-scale hydroponic cultivation system 1 is constructed by connecting multiple greenhouses.

[0108] The cultivation beds or houses A to E are connected in parallel by pipes 21 and 22. The pipes 21 and 22 are used to circulate the culture solution within the hydroponic cultivation system 1. In Fig. 2, the lines indicate the pipes 21 and 22, and the arrows indicate the flow direction of the culture solution.

[0109] In the five cultivation beds or houses A to E, different types of crops are hydroponically grown, including plants from the Asteraceae or Lamiaceae families and other plants (root vegetables, leafy vegetables, fruit vegetables, flowers, etc.).

[0110] The culture solution flowing out from the cultivation bed or house E is driven by the power of pump P1 and flows into the cultivation beds or houses A to D via pipe 21. After flowing into the cultivation beds or houses A, B, C, and D, the culture solution is supplied to the respective cultivated crops, and then returned to the cultivation bed or house E via pipe 22 by the power of downstream pumps P2, P3, P4, and P5.

[0111] Upstream of the cultivation beds or houses A, B, C, and D, valves 31, 32, 33, and 34 are provided to adjust the inflow rate of the culture solution, respectively.

[0112] In the hydroponic cultivation system 1 shown in Figure 2, when plants of the Asteraceae or Lamiaceae family are cultivated in cultivation bed or house E, hydrogen peroxide secreted from the roots of the Asteraceae or Lamiaceae plants flows into cultivation beds or houses A to D via piping 21 and reacts with the polyphenol-iron complex to induce the Fenton reaction. In this way, the Fenton reaction can provide a powerful bactericidal effect and organic matter decomposition effect in all cultivation beds or houses. In addition to the polyphenol-iron complex, the culture solution also contains a plant or mushroom extract trace element complex with bactericidal activity, which also contributes to disease control throughout the hydroponic cultivation system 1.

[0113] For example, if the crops in the cultivation beds or house A suffer from disease or autointoxication, valves 32, 33, and 34 are closed, and the culture solution containing the plant or mushroom extract trace element complex and hydrogen peroxide flows only into the cultivation beds or house A. This allows for concentrated sterilization and decomposition and removal of organic matter in the cultivation beds or house A.

[0114] 2, even when plants of the Asteraceae or Lamiaceae family are cultivated in a location other than the cultivation bed or house E, the culture solution is circulated via pipes 21 and 22, so that hydrogen peroxide secreted from the plants of the Asteraceae or Lamiaceae family is supplied to all of the cultivation beds or houses. Therefore, the plant or mushroom extract trace element complex can exert a powerful bactericidal effect and an organic substance decomposition effect throughout the entire hydroponic cultivation system 1.

[0115] Another form of "mixed cultivation" is, for example, as shown in Figure 3, a method in which two or more types of plants are cultivated in the same hydroponic cultivation area and the nutrient solution is circulated within this hydroponic cultivation area.

[0116] Figure 3 shows another embodiment of mixed cultivation of plants of the Asteraceae or Lamiaceae family with other plants. The hydroponic cultivation system 1 is mainly composed of a cultivation bed 4 and piping 2. The piping 2 is connected downstream and upstream of the cultivation bed 4, and circulates the nutrient solution within the hydroponic cultivation system 1. In Figure 3, the lines indicate the piping 2, and the arrows indicate the flow direction of the nutrient solution.

[0117] Among sections A to E in the cultivation bed 4, at least one section hydroponically cultivates plants of the Asteraceae or Lamiaceae family. In the remaining sections, any crops of plants other than the Asteraceae and Lamiaceae families (root vegetables, leafy vegetables, fruit vegetables, flowers, etc.) are hydroponically cultivated.

[0118] Pump P is installed on pipe 2 and circulates the nutrient solution in the direction of the arrow. The nutrient solution discharged from downstream of the cultivation bed 4 is returned to the upstream of the cultivation bed 4 via pipe 2 by the power of pump P. The nutrient solution flowing in from upstream of the cultivation bed 4 is supplied to the cultivated crops in sections A to E, and then discharged again from downstream.

[0119] In the hydroponic cultivation system 1 shown in Figure 3, hydrogen peroxide secreted from the roots of plants of the Asteraceae or Lamiaceae family is circulated within the hydroponic cultivation system 1 along with the flow of the nutrient solution. As a result, in all sections of the cultivation bed 4, the polyphenol-iron complex in the nutrient solution reacts with hydrogen peroxide to initiate a Fenton reaction, which enables the Fenton reaction to produce powerful bactericidal and organic matter decomposition effects. In addition to the polyphenol-iron complex, the nutrient solution also contains a plant or mushroom extract trace element complex with bactericidal properties, which also works to prevent disease throughout the hydroponic cultivation system 1.

[0120] In this way, in this embodiment, by cultivating the Asteraceae or Lamiaceae plants in at least a part of a hydroponic cultivation system in which the culture solution is circulated, it is possible to obtain the effects of powerful bactericidal and organic matter decomposition effects throughout the entire system. [Example]

[0121] The present embodiment will be described in detail below with reference to examples.

[0122] (Test Example 1) Detection of hydrogen peroxide in the roots of plants of the Asteraceae family and Lamiaceae family To confirm that hydrogen peroxide is secreted from the roots of Asteraceae (chrysanthemum) and Lamiaceae (perilla) plants, the hydrogen peroxide concentration on the root surface was measured.

[0123] Chrysanthemums and perilla plants grown hydroponically were pulled out and the hydrogen peroxide concentration in the water adhering to the surface of the roots was measured using hydrogen peroxide test paper (Merck). As a result, hydrogen peroxide levels of over 30 mg / L were detected in chrysanthemums and over 100 mg / L in perilla.

[0124] It is known that hydrogen peroxide is contained in the roots of not only chrysanthemums but also all Asteraceae plants. In this test example, high concentrations of hydrogen peroxide were detected on the surface of chrysanthemum roots, suggesting that hydrogen peroxide exudes from the roots of all Asteraceae plants. It was also suggested that hydrogen peroxide exudes from the roots of Lamiaceae plants, just like Asteraceae plants.

[0125] (Preparation Example 1) Preparation of polyphenol and trace element mixture The plant extract trace element mixture (stock solution) used in the following examples was prepared as follows.

[0126] (1) Extraction of polyphenols The polyphenol-containing plants used were acacia leaves and stems, tea leaves (green tea), coffee grounds, coffee tree leaves and stems, chrysanthemum flowers, bamboo shoot skin, grape pomace (residue from the wine-making process), banana fruit (with the skin removed), sweet potato leaves and stems, and cedar leaves and stems.

[0127] 10 g (dry weight) of each of the above polyphenol-containing plants and 700 mL of distilled water were placed in a 1000 mL beaker and heated under pressure at 120°C for 20 minutes. The mixture was filtered through filter paper to obtain a polyphenol-containing plant extract.

[0128] (2) Mixing with trace elements Powdered trace element compounds were added to the resulting polyphenol-containing plant extracts and dissolved by stirring. Distilled water was added to make 1 L, and a plant extract trace element mixture (stock solution) with the composition shown in Table 2 was obtained. The composition in Table 2 was determined based on the composition of trace elements in commercially available liquid fertilizers for hydroponic cultivation.

[0129] [Table 1]

[0130] In the above-mentioned plant extract trace element mixture, iron ions derived from iron sulfate (II) are converted into Fe by polyphenols extracted from various polyphenol-containing plants. 2+ It is believed that the plant extract and trace element mixture contains polyphenol-iron complexes that are chelated in the above-mentioned state. It is also believed that the plant extract and trace element mixture contains complexes of the plant extract and trace elements other than iron.

[0131] (Test Example 2) Prevention of bacterial wilt by mixed cultivation with Asteraceae plants The inhibitory effect of acacia extract on bacterial wilt disease was investigated by cultivating mixed plants of lisianthus (Gentianaceae) and aster (Asteraceae).

[0132] A commercially available liquid fertilizer for hydroponics ("OAT House" A formulation, manufactured by OAT Agrio) was mixed with 1 x 10 3 The culture medium was prepared by adding the bacteria to a density of 1000 cfu / mL.

[0133] Monoculture treatment: Only lisianthus seedlings were planted in the cultivation beds and cultivated hydroponically. The above culture solution without acacia extract was used. Mixed cultivation treatment: Eustoma and aster seedlings were planted in the same cultivation bed and mixed cultivation was performed. The above nutrient solution containing acacia extract was used.

[0134] Acacia extract was added to the mixed cultivation treatment as follows: After planting, 50 mL of the plant extract trace element mixture (stock solution) prepared using acacia extract in Preparation Example 1 was added to 50 L of culture medium (1000-fold dilution) at two-week intervals until flower differentiation.

[0135] During the flowering stage, 100 mL (500-fold dilution) of the above-mentioned plant extract trace element mixture (stock solution) was added in four separate doses to 50 L of culture solution. This was because adding 100 mL all at once could cause physiological disorders in the plant due to the high concentration of polyphenols. Therefore, 25 mL of the plant extract trace element mixture (stock solution) was added over two days while observing the condition of the roots.

[0136] In both treatment areas, a pump was used to flow the nutrient solution in one direction from the nutrient solution tank to the cultivation beds, and then it was returned to the nutrient solution tank. This meant that the nutrient solution was not replaced (discarded), and hydroponic cultivation was carried out using a fully circulating system. Furthermore, no solid medium such as rock wool was used, and the pH and EC of the nutrient solution were not controlled. A float system was used to automatically replenish water without using electricity, maintaining the nutrient solution volume at 50 L.

[0137] The number of withered lisianthus plants was measured in each treatment area during cultivation. The results are shown in Figures 4 and 5. Figure 4 is a photographic image showing the monoculture (left) and mixed planting (right) cultivations. Figure 5 is a graph showing the results of the bacterial wilt suppression test. In Figure 5, the vertical axis indicates the number of withered plants, the horizontal axis indicates the number of days from the start of cultivation, ▲ indicates the monoculture treatment area, and ◯ indicates the mixed planting treatment area.

[0138] As shown in Figures 4 and 5, most of the lisianthus plants in the monoculture treatment area died and were unable to grow to flower, whereas in the mixed cultivation treatment area, almost all of the plants grew healthily. The disease outbreak in the lisianthus plants in the monoculture treatment area started with sporadic wilting of one or two plants, but the number of affected plants gradually increased (Figure 5).

[0139] These results demonstrate that adding polyphenol-containing plant extracts to the nutrient solution and cultivating them in combination with Asteraceae plants can protect crops from disease without changing the nutrient solution or sterilizing them with chemicals, ozone, or ultraviolet light. The Fenton reaction occurs between hydrogen peroxide secreted from the roots of Asteraceae plants and the polyphenol-iron complex contained in the nutrient solution, generating hydroxyl radicals with potent bactericidal effects. Furthermore, in addition to the polyphenol-iron complex, the nutrient solution also contains a plant extract trace element complex with antibacterial properties. It is believed that the synergistic effect of these plant extract trace element complexes sterilizes or inhibits the growth of pathogenic microorganisms such as bacterial wilt.

[0140] (Test Example 3) Hydroponic cultivation test using tea extracts of different concentrations The effect of varying the concentration of tea extract in the culture solution on the hydroponic cultivation of lettuce (Asteraceae) was investigated.

[0141] (1) Preparation of culture medium Tea leaves (green tea) were used as the polyphenol-containing plant material. 0 g, 1 g, 2.5 g, 5 g, and 10 g of dried tea leaves and 700 mL of distilled water were placed in a 1000 mL beaker and heated at 120°C under pressure for 20 minutes. The mixture was filtered through filter paper to obtain tea extracts. Each concentration of tea extract was added to 5 L of culture solution with the composition shown in Table 3 and used for hydroponic cultivation.

[0142] [Table 2] *Indicates the weight (dry weight) of tea leaves used as the extraction material.

[0143] (2) Hydroponic cultivation test As shown in Figure 6, a hydroponic cultivation test for lettuce was conducted using 5 L of the above-mentioned culture solution. Lettuce seedlings were planted in each container, and hydroponic cultivation was carried out while supplying oxygen to the culture solution with an air pump. During cultivation, the culture solution was not added or replaced, and pH and EC were not controlled. 40 days after planting, the chlorophyll content (SPAD value) of the lettuce leaves was measured using a chlorophyll meter.

[0144] (3) Results and Discussion The results are shown in Figure 7. In Figure 7, the vertical axis indicates the SPAD value of the leaves, the horizontal axis indicates the treatment groups, and the bars indicate the standard deviation (n=3).

[0145] The lettuce plants in the nutrient solution containing the tea extract showed good growth, while the lettuce plants in the control area showed poor growth, likely due to a lack of trace elements. Furthermore, the higher the amount of tea leaves used, the higher the SPAD value of the leaves. The lettuce plants in the control area had lower SPAD values ​​than those in the tea extract-added area (Figure 7).

[0146] These results indicate that adding polyphenol-containing plant extracts to the culture solution can prevent crop growth disorders caused by trace element deficiencies. This is thought to be because the chelating effect of the plant extracts maintains the trace elements in a form that is easily absorbed by the plant. There was a tendency for the chlorophyll content to increase with increasing concentration of polyphenol-containing plant extracts, which is also thought to be due to the promotion of trace element absorption.

[0147] (Example 1) Mixed cultivation of chrysanthemums using acacia extract As shown in Figure 8, small-flowered and large-flowered chrysanthemum seedlings were planted together in the same cultivation bed in a greenhouse, and hydroponic cultivation was performed with the addition of acacia extract. A commercially available liquid fertilizer for hydroponic culture ("OAT House" Formulation A, manufactured by OAT Agrio) was used as the culture solution. Acacia extract was added to the culture solution as follows.

[0148] First, at the start of cultivation and three weeks later, 33 mL of the plant extract trace element mixture (stock solution) prepared using acacia extract in Preparation Example 1 was added to 100 L of culture solution (3000-fold dilution). During the subsequent stem growth period, 100 mL of the plant extract trace element mixture (stock solution) was added to 100 L of culture solution at two-week intervals (1000-fold dilution).

[0149] Furthermore, during the flowering stage, 200 mL (500-fold dilution) of the above-mentioned plant extract trace element mixture (undiluted solution) was added in four separate doses to 100 L of culture solution. This was because adding 200 mL all at once could cause physiological disorders in the plant due to the high concentration of polyphenols. Therefore, 50 mL of the plant extract trace element mixture (undiluted solution) was added in increments over two days while observing the condition of the roots.

[0150] The equipment used a pump to flow the nutrient solution in one direction from the nutrient solution tank to the cultivation bed, then return it to the nutrient solution tank, performing a fully circulating hydroponic system without replacing (discarding) the nutrient solution. Furthermore, no solid medium such as rock wool was used, and the pH and EC of the nutrient solution were not managed. A float system automatically replenished water without using electricity, maintaining the nutrient solution volume at 100L.

[0151] The hydroponic cultivation method described above enabled the production of high-quality chrysanthemums without discarding the culture solution (Figure 8). By adding polyphenol-containing plant extracts to the culture solution, trace elements were chelated, preventing trace element deficiency symptoms without the need for pH control. Furthermore, the Fenton reaction occurs between the polyphenol-iron complex (a Fenton reaction catalyst), a reaction product of polyphenols and iron, and hydrogen peroxide exuded from the chrysanthemum roots, resulting in a powerful bactericidal effect. Furthermore, plant extract trace element complexes other than the polyphenol-iron complex also have antibacterial properties, preventing disease outbreaks without the need for clean rooms, special sterilization equipment, or chemicals. Furthermore, the decomposition of organic substances by the Fenton reaction can also decompose allelopathic substances, preventing growth disorders due to autointoxication.

[0152] (Example 2) Mixed cultivation of lisianthus and aster using tea extract As shown in Figure 9, eustoma (gentianaceae) and aster (Asteraceae) seedlings were planted together in the same cultivation bed in a greenhouse, and hydroponic cultivation was performed with the addition of tea extract. A commercially available liquid fertilizer for hydroponic culture ("OAT House" Formulation A, manufactured by OAT Agrio) was used as the culture solution. The tea extract was added to the culture solution as follows.

[0153] First, at the start of cultivation and thereafter for four weeks, 33 mL of the plant extract trace element mixture (stock solution) prepared using tea extract in Preparation Example 1 was added to 100 L of culture solution at seven-day intervals (3000-fold dilution). During the subsequent stem growth period, 100 mL of the plant extract trace element mixture (stock solution) was added to 100 L of culture solution at two-week intervals (1000-fold dilution).

[0154] Furthermore, from the flowering stage onwards, 200 mL (500-fold dilution) of the above-mentioned plant extract trace element mixture (stock solution) was added to 100 L of culture solution twice at two-week intervals. This 200 mL stock solution was added in four separate additions. This was because adding 200 mL all at once could cause physiological disorders in the plant due to the high concentration of polyphenols. Therefore, 50 mL of the plant extract trace element mixture (stock solution) was added in increments over two days while observing the condition of the roots.

[0155] The equipment used a pump to flow the nutrient solution in one direction from the nutrient solution tank to the cultivation bed, then return it to the nutrient solution tank, performing a fully circulating hydroponic system without replacing (discarding) the nutrient solution. Furthermore, no solid medium such as rock wool was used, and the pH and EC of the nutrient solution were not managed. A float system automatically replenished water without using electricity, maintaining the nutrient solution volume at 100L.

[0156] As a result of the above, we were able to produce high-quality lisianthus and asters using hydroponic cultivation without pH adjustment, with zero wastewater, and with significantly less environmental impact than conventional methods (Figure 9). Even when Asteraceae plants are planted together with non-Asteraceae plants, hydrogen peroxide exuded from the roots of Asteraceae plants travels throughout the hydroponic cultivation system with the flow of the nutrient solution, reacting with polyphenol-iron complexes to prevent disease and autointoxication throughout the system. Furthermore, the addition of tea extract to the nutrient solution chelates trace elements, providing additional antibacterial effects and preventing trace element deficiency symptoms even without pH control.

[0157] (Example 3) Mixed cultivation of statice and cornflower using coffee extract As shown in Figure 10, statice (Plumbaceae) and cornflower (Asteraceae) seedlings were planted together in the same cultivation bed in a greenhouse and grown hydroponically with the addition of coffee extract. A commercially available liquid fertilizer for hydroponics ("OAT House" Formulation A, manufactured by OAT Agrio) was used as the nutrient solution. The coffee extract was added to the nutrient solution as follows.

[0158] First, at the start of cultivation and three weeks later, 33 mL of the plant extract trace element mixture (stock solution) prepared using coffee (grounds) extract in Preparation Example 1 was added to 100 L of culture solution (3000-fold dilution). During the subsequent stem growth period, 100 mL of the plant extract trace element mixture (stock solution) was added to 100 L of culture solution at two-week intervals (1000-fold dilution).

[0159] Furthermore, during the flowering stage, 200 mL (500-fold dilution) of the above-mentioned plant extract trace element mixture (undiluted solution) was added in four separate doses to 100 L of culture solution. This was because adding 200 mL of the undiluted solution all at once could cause physiological disorders in the plant due to the high concentration of polyphenols. Therefore, 50 mL of the plant extract trace element mixture (undiluted solution) was added in increments over two days while observing the condition of the roots.

[0160] The equipment used a pump to flow the nutrient solution in one direction from the nutrient solution tank to the cultivation bed, then return it to the nutrient solution tank, performing a fully circulating hydroponic system without replacing (discarding) the nutrient solution. Furthermore, no solid medium such as rock wool was used, and the pH and EC of the nutrient solution were not managed. A float system automatically replenished water without using electricity, maintaining the nutrient solution volume at 100L.

[0161] As a result, high-quality cut flowers could be produced without discarding the nutrient solution (Figure 10). By cultivating Asteraceae plants together with non-Asteraceae plants, the hydrogen peroxide exuded from the roots of the Asteraceae plants reacts with the polyphenol-iron complex, enabling disease control and autointoxication prevention throughout the hydroponic cultivation system. Furthermore, even when coffee grounds, an extraction residue, were used as the polyphenol-containing plant material, adding the extract to the nutrient solution chelated trace elements, providing further antibacterial effects, and demonstrating no trace element deficiency symptoms, even without pH control.

[0162] Example 4: Hydroponic cultivation of lisianthus using coffee extract As shown in Figure 11, eustoma (gentianaceae) seedlings were planted in a cultivation bed in a greenhouse and hydroponically grown with the addition of coffee extract. A commercially available liquid fertilizer for hydroponics ("OAT House" Formulation A, manufactured by OAT Agrio) was used as the culture solution. The coffee extract was added to the culture solution as follows.

[0163] First, at the start of cultivation and then over the next four weeks, 33 mL of the plant extract trace element mixture (stock solution) prepared using coffee (leaf and stem) extract in Preparation Example 1 was added to 100 L of culture medium at seven-day intervals (3000-fold dilution). During the subsequent stem growth period, 100 mL of the plant extract trace element mixture (stock solution) was added to 100 L of culture medium at two-week intervals (1000-fold dilution).

[0164] Furthermore, from the flowering stage onwards, 200 mL (500-fold dilution) of the above-mentioned plant extract trace element mixture (stock solution) was added to 100 L of culture solution twice at two-week intervals. This 200 mL stock solution was added in four separate additions. This was because adding 200 mL all at once could cause physiological disorders in the plant due to the high concentration of polyphenols. Therefore, 50 mL of the plant extract trace element mixture (stock solution) was added in increments over two days while observing the condition of the roots.

[0165] As a control, hydroponic cultivation was carried out in the same manner as above, except that a commercially available liquid fertilizer for hydroponic cultivation was used instead of the plant extract trace element mixture solution, for comparison.

[0166] In both treatment areas, a pump was used to flow the nutrient solution in one direction from the nutrient solution tank to the cultivation beds, and then it was returned to the nutrient solution tank. This meant that the nutrient solution was not replaced (discarded), and hydroponic cultivation was carried out using a fully circulating system. Furthermore, no solid medium such as rock wool was used, and the pH and EC of the nutrient solution were not controlled. A float system automatically replenished water without using electricity, maintaining the nutrient solution volume at 100 L.

[0167] The eustoma plants treated with coffee extract grew healthily and produced high-quality cut flowers. Meanwhile, the eustoma plants in the control area developed physiological disorders in the leaves that were thought to be caused by trace element deficiencies, and growth was poor (Figure 11). By adding coffee extract to the nutrient solution, the trace elements were chelated, preventing trace element deficiency symptoms without pH control, and antibacterial effects were also obtained. Furthermore, even when plants are not planted together with Asteraceae or Lamiaceae plants, trace amounts of biogenic hydrogen peroxide are generated in the nutrient solution, which reacts with polyphenol-iron complexes to initiate the Fenton reaction, enabling disease control and suppression of autointoxication.

[0168] Example 5: Hydroponic cultivation of blue thistle using tea extract As shown in Figure 12, seedlings of blue thistle (Asteraceae) were planted in containers in a greenhouse, and hydroponics was performed with the addition of tea extract. A commercially available liquid fertilizer for hydroponics ("OAT House" Formulation A, manufactured by OAT Agrio) was used as the culture solution, and the tea extract was added to the culture solution as follows.

[0169] First, at the start of cultivation and then over the next three weeks, 33 mL of the plant extract trace element mixture (stock solution) prepared using tea extract in Preparation Example 1 was added to 100 L of culture medium at seven-day intervals (3000-fold dilution). Thereafter, 100 mL of the plant extract trace element mixture (stock solution) was added to 100 L of culture medium at two-week intervals (1000-fold dilution).

[0170] As a control, hydroponic cultivation was carried out in the same manner as above, except that a commercially available liquid fertilizer for hydroponic cultivation was used instead of the plant extract trace element mixture solution, for comparison.

[0171] In both treatment areas, oxygen was supplied to the culture solution using an air pump, and the pH and EC of the culture solution were not controlled, nor was the culture solution replaced (discarded). Furthermore, no solid medium such as rock wool was used. A float system automatically replenished water without using electricity, maintaining the culture solution volume at 100 L.

[0172] The blue thistle plants treated with tea extract grew healthily and produced high-quality cut flowers. Meanwhile, the blue thistle plants in the control area developed physiological disorders in their leaves, likely due to trace element deficiencies, and growth was poor (Figure 12). The chelating effect of the tea extract aids in the absorption of trace elements, eliminating the need for pH management. Furthermore, even without planting them together with plants from the Asteraceae or Lamiaceae families, the antiseptic properties of the plant extract trace element complex and the organic matter-decomposing properties of the polyphenol iron complex work to prevent disease and curb autointoxication.

[0173] (Example 6) Hydroponic cultivation of lilies using extracts from various polyphenol-containing plants In a vinyl greenhouse, lily (Casablanca) bulbs were planted in the hydroponic cultivation apparatus shown in FIG. 13, and hydroponic cultivation was carried out with the addition of extracts of various polyphenol-containing plants.

[0174] (1) Preparation of plant extract and trace element mixture The polyphenol-containing plant materials used were tea leaves (green tea), grape pomace (pomace from wine production), acacia leaves and stems, poplar leaves and stems, willow leaves and stems, and chrysanthemum leaves and stems. Ten grams (dry weight) of each of the polyphenol-containing plant materials listed above and 700 mL of distilled water were placed in a 1000 mL beaker and heated at 120°C under pressure for 20 minutes. The resulting solution was filtered through filter paper to obtain a polyphenol-containing plant extract.

[0175] Powdered trace element compounds (boric acid 3g, manganese(II) sulfate 2g, zinc sulfate 0.22g, copper sulfate 0.05g, sodium molybdate 0.01g, iron(II) sulfate 15g) were added to the obtained polyphenol-containing plant extract and dissolved by stirring. Distilled water was added to this to make 1 L, and a plant extract trace element mixture (stock solution) was obtained.

[0176] (2)Cultivation method The bulbs were stored at 13°C for two months before being planted in the apparatus shown in Figure 13. Because lilies have roots not only at the bottom but also at the top of the bulb (superficial roots), the bulbs were planted in containers filled with moistened peat moss.

[0177] As shown in Figure 14, four lilies were grown in each cultivation pot in each treatment area. A pump was used to flow the nutrient solution in one direction from the nutrient solution tank to the cultivation pots, and then it was returned to the nutrient solution tank. This was a fully circulating hydroponic cultivation method, with no replacement (disposal) of the nutrient solution. Furthermore, the pH and EC of the nutrient solution were not controlled. A float system was used to automatically replenish water without using electricity, maintaining the nutrient solution volume at 15 L.

[0178] A commercially available liquid fertilizer for hydroponics ("OAT House" Formulation A, manufactured by OAT Agrio) was used as the culture solution. Extracts of various polyphenol-containing plants were added to the culture solution as follows.

[0179] First, from the start of cultivation until the flowering stage, 5 mL of the trace element mixture (stock solution) of various plant extracts prepared in (1) above was added to 15 L of culture medium at two-week intervals (3000-fold dilution). After the flowering stage, 15 mL of the trace element mixture (stock solution) of various plant extracts was added to 15 L of culture medium at two-week intervals (1000-fold dilution).

[0180] After flowering, the diameter of the lily flowers was measured (Figure 15). A control group (no plant extract added) was grown hydroponically in the same manner as above, except that a commercially available liquid fertilizer for hydroponics was used instead of the plant extract trace element mixture. A control group (iron chloride) was grown hydroponically in the same manner as above, except that 8.8 g of iron(III) chloride was added instead of the trace element compound in (1) above.

[0181] (3) Results and Discussion As shown in Figure 14, high-quality lilies were produced in all treatment groups. Figure 16 is a graph showing the effect on lily flowers of the addition of extracts from various polyphenol-containing plants. In Figure 16, the vertical axis represents flower diameter (cm), the horizontal axis represents treatment groups, and the bars represent standard deviation (n=4). Compared to the control group (no plant extract added), flower length (flower diameter) was longer in all treatment groups with added plant extracts.

[0182] Lily cultivation requires a great deal of labor, and it is considered difficult to cultivate high-quality lilies. Furthermore, there is a problem in that lilies cannot be cultivated in the same area every year due to the risk of continuous cropping. In this example, by adding extracts from various polyphenol-containing plants to the culture solution, pH control of the culture solution is no longer necessary, and disease prevention and suppression of autointoxication are also possible. Therefore, not only can lilies be cultivated easily, but the problem of continuous cropping problems can also be solved. Furthermore, waste of culture solution is eliminated, enabling environmentally friendly agriculture.

[0183] (Example 7) Hydroponic cultivation of paprika using chrysanthemum, bamboo, and grape extracts As shown in FIG. 17, paprika (Solanaceae) seedlings were planted in a cultivation bed in a greenhouse, and hydroponics was carried out with the addition of extracts from chrysanthemum, bamboo, and grapes.

[0184] A commercially available liquid fertilizer for hydroponics ("OAT House" Formulation A, manufactured by OAT Agrio) was used as the culture solution. The polyphenol-containing plant extracts added to the culture solution were prepared using a mixture of trace elements from various plant extracts (stock solution) prepared in Preparation Example 1 using chrysanthemum (flower) extract, bamboo (bamboo shoot skin) extract, and grape (pomace) extract.

[0185] The polyphenol-containing plant extracts were added to the culture medium as follows: First, at the start of cultivation and for the next four weeks, 33 mL of the above-mentioned mixture of trace elements from various plant extracts (stock solution) was added to 100 L of culture medium at seven-day intervals (3000-fold dilution). During the subsequent stem growth period, 100 mL of the above-mentioned mixture of trace elements from various plant extracts (stock solution) was added to 100 L of culture medium at two-week intervals (1000-fold dilution).

[0186] Furthermore, from the flowering stage onwards, 200 mL (500-fold dilution) of the above-mentioned plant extract trace element mixture (stock solution) was added to 100 L of culture solution twice at two-week intervals. This 200 mL stock solution was added in four separate additions. This was because adding 200 mL all at once could cause physiological disorders in the plant due to the high concentration of polyphenols. Therefore, 50 mL of the plant extract trace element mixture (stock solution) was added in increments over two days while observing the condition of the roots.

[0187] The equipment used a pump to flow the nutrient solution in one direction from the nutrient solution tank to the cultivation bed, then return it to the nutrient solution tank, performing a fully circulating hydroponic system without replacing (discarding) the nutrient solution. Furthermore, no solid medium such as rock wool was used, and the pH and EC of the nutrient solution were not managed. A float system automatically replenished water without using electricity, maintaining the nutrient solution volume at 100L.

[0188] Paprika plants supplemented with extracts of various polyphenol-containing plants grew healthily and produced high-quality fruit (Figure 18). The chelating effect of extracts of various polyphenol-containing plants aids the absorption of trace elements, eliminating the need for pH control. While solid media such as rock wool are commonly used in hydroponic cultivation of fruit vegetables to aid nutrient absorption, the cultivation method of this embodiment does not impair growth even without the use of solid media. Furthermore, even without co-planting with plants of the Asteraceae or Lamiaceae families, the bactericidal action of the plant extract trace element complex and the organic substance decomposition action of the polyphenol iron complex enable disease control and the suppression of autointoxication.

[0189] Example 8 Hydroponic cultivation of strawberries using banana and sweet potato extracts As shown in FIG. 19, strawberry (Rosaceae) seedlings were planted in containers in a vinyl greenhouse, and hydroponics was carried out with the addition of banana extract or sweet potato extract.

[0190] A commercially available liquid fertilizer for hydroponics ("OAT House" Formulation A, manufactured by OAT Agrio) was used as the culture solution. The polyphenol-containing plant extracts added to the culture solution were the various plant extract trace element mixtures (stock solution) prepared using banana (fruit) extract and sweet potato (leaf and stem) extract in Preparation Example 1.

[0191] The polyphenol-containing plant extract was added to the culture medium as follows: First, at the start of cultivation and then over the next four weeks, 33 mL of the above-mentioned mixture of trace elements from various plant extracts (stock solution) was added to 100 L of culture medium at seven-day intervals (3000-fold dilution). During the subsequent stem growth period, 100 mL of the above-mentioned mixture of trace elements from various plant extracts (stock solution) was added to 100 L of culture medium at two-week intervals (1000-fold dilution).

[0192] As a control, hydroponic cultivation was carried out in the same manner as above, except that a commercially available liquid fertilizer for hydroponic cultivation was used instead of the plant extract trace element mixture solution, for comparison.

[0193] In both treatment areas, oxygen was supplied to the culture solution using an air pump, and the pH and EC of the culture solution were not controlled, nor was the culture solution replaced (discarded). Furthermore, no solid medium such as rock wool was used. A float system automatically replenished water without using electricity, maintaining the culture solution volume at 100 L.

[0194] Strawberries treated with polyphenol-containing plant extracts grew healthily. In contrast, the leaves of the control strawberries showed physiological disorders (leaf yellowing) likely due to trace element deficiency (Figure 19). The chelating effect of polyphenol-containing plant extracts aids trace element absorption, eliminating the need for pH control. While solid media such as rock wool are typically used in hydroponic strawberry cultivation, the cultivation method of this embodiment eliminates the need for solid media, eliminating the need for solid media disposal after cultivation. Furthermore, even without co-planting with plants of the Asteraceae or Lamiaceae families, the bactericidal action of the plant extract trace element complex and the organic substance-decomposing action of the polyphenol iron complex enable disease control and the prevention of autointoxication.

[0195] (Example 9) Hydroponic cultivation of strawberries using extracts from various polyphenol-containing plants In a greenhouse, strawberry seedlings (variety name "Benihoppe") were planted in the hydroponic cultivation apparatus shown in FIG. 20, and hydroponic cultivation was carried out by adding extracts of various polyphenol-containing plants.

[0196] (1) Preparation of plant extract and trace element mixture The polyphenol-containing plant extracts used were ginkgo leaves and stems, coffee leaves and stems, papaya leaves and stems, cedar leaves and stems, perilla leaves and stems, pine leaves and stems, mango leaves and stems, cacao leaves and stems, banana leaves and stems, yuzu fruit, lemon leaves and stems, and guava leaves and stems. Ten grams (dry weight) of each of the polyphenol-containing plant extracts and 700 mL of distilled water were placed in a 1000 mL beaker and heated at 120°C under pressure for 20 minutes. The extract was then filtered through a paper filter to obtain a polyphenol-containing plant extract.

[0197] Powdered trace element compounds (boric acid 3g, manganese(II) sulfate 2g, zinc sulfate 0.22g, copper sulfate 0.05g, sodium molybdate 0.01g, iron(II) sulfate 15g) were added to the obtained polyphenol-containing plant extract and dissolved by stirring. Distilled water was added to this to make 1 L, and a plant extract trace element mixture (stock solution) was obtained.

[0198] (2)Cultivation method 9 L of culture solution was placed in the polystyrene foam box shown in Figure 20, and hydroponic cultivation was performed while circulating the culture solution by supplying oxygen with an air pump. The pH and EC of the culture solution were not controlled, and the culture solution was not replaced (discarded). In addition, no solid medium such as rock wool was used.

[0199] A commercially available liquid fertilizer for hydroponics ("OAT House" Formulation A, manufactured by OAT Agrio) was used as the culture solution. At two-week intervals from the start of cultivation, 9 mL (1000-fold dilution) of the trace element mixture (stock solution) of various plant extracts prepared in (1) above and 9 mL of the above-mentioned commercially available liquid fertilizer were added to 9 L of culture solution. Water was manually replenished every three weeks to maintain the culture solution volume at 9 L.

[0200] Forty days after planting, the SPAD value, an index of chlorophyll content, was measured using a chlorophyll meter. Strawberry fruits were harvested over a three-week period, beginning 80 days after planting, and the yield was measured. A control group was grown hydroponically in the same manner as above, except that a commercially available liquid fertilizer was used instead of the plant extract trace element mixture.

[0201] (3) Results and Discussion Figure 21 is a photograph comparing the appearance of (a) the control plot and (b) the ginkgo extract-added plot 55 days after planting. In the control plot, physiological disorders (yellowing of young leaves) thought to be due to trace element deficiency were evident, and the strawberry yield was low. On the other hand, in the plant extract-added plot, no growth disorders occurred, and more strawberry fruits were harvested than in the control plot (see Figure 23).

[0202] Figure 22 is a graph comparing the chlorophyll content (SPAD values) of strawberries in each treatment group. In the figure, the vertical axis represents the SPAD value, the horizontal axis represents the treatment group, the bars represent the standard deviation, and different letters indicate significant differences at the 5% significance level (n=3). All plant extract-added groups had significantly higher chlorophyll content than the control group (Figure 22).

[0203] Figure 23 is a graph comparing the total weight of strawberry fruit harvested over three weeks in each treatment area (average value per plant, n=3). In the figure, the vertical axis represents total fruit weight (g), the horizontal axis represents treatment area, the bars represent standard deviation, and different letters indicate significant differences at the 5% significance level. All plant extract-added areas had significantly higher yields than the control area (Figure 23). It is believed that the chlorophyll content of the strawberries in the control area decreased due to growth impairment. It is believed that plants with low chlorophyll content have reduced photosynthetic ability, leading to a significant decrease in yield.

[0204] The optimum pH for plant growth in a culture solution is generally considered to be 5.5 to 6.5. Outside this pH range, trace elements change into a form that is not absorbed by plants and precipitate, leading to conventional pH adjustments such as the addition of acid or alkali to the culture solution. In this example, the pH of the culture solution was measured two months after planting. The pH exceeded 6.5 in all treatments due to an imbalance in the nutrient solution composition. Consequently, growth impairment occurred in the control group due to a lack of trace elements (Figures 21 to 23). In contrast, in the treatment group where polyphenol-containing plant extracts were added to the culture solution, the trace elements were chelated, making them more readily absorbed by plants, presumably preventing growth impairment.

[0205] (Example 10) Mixed cultivation of Asteraceae plants and root vegetables using cedar extract In a greenhouse, seedlings of Daikon radish (Brassicaceae) and Dimorphotheca (Asteraceae) were planted together in a commercially available hydroponic cultivation device shown in FIG. 24, and cedar extract was added to the seedlings, followed by hydroponic cultivation for 40 days.

[0206] As shown in Figures 24 and 25, radishes were planted in three of the four cultivation pipes of the hydroponic cultivation device, and Dimorphotheca was planted in the remaining cultivation pipe. A pump was used to flow the nutrient solution in one direction from the nutrient solution tank to the cultivation pipes, and then the solution was returned to the nutrient solution tank. This complete circulation hydroponic cultivation method did not require replacement (disposal) of the nutrient solution. Furthermore, no solid medium such as rock wool was used, and the pH and EC of the nutrient solution were not controlled. A float system automatically replenished water without using electricity, maintaining the nutrient solution volume at 15 L.

[0207] A commercially available liquid fertilizer (Hyponex (registered trademark) concentrate, diluted 3000 times, manufactured by Hyponex Japan Co., Ltd.) was used as the culture solution. Hydroponic cultivation was started using 15 mL of the plant extract trace element mixture (concentrate) prepared using the cedar (leaf and stem) extract in Preparation Example 1, diluted 1000 times with this culture solution.

[0208] Starting one week after the start of cultivation, 15 mL (1000-fold dilution) of the above-mentioned plant extract trace element mixture (stock solution) and 5 mL (3000-fold dilution) of "Hyponex (registered trademark) stock solution" were added to 15 L of culture medium at 7-day intervals.

[0209] After harvesting, the yield of radish was measured. As a control, hydroponic cultivation was carried out in the same manner as above, except that a commercially available liquid fertilizer was used instead of the plant extract trace element mixture.

[0210] The results are shown in Figures 25 and 26. Figure 25 is a photograph comparing the mixed planting conditions in the plant extract-added area and the control area. Although it is not clear from Figure 25, growth disorders (yellowing of leaves) occurred in the radishes in the control area, whereas no growth disorders occurred in the plant extract-added area and the radishes grew healthily. It is thought that growth disorders occurred in the control area due to a deficiency of trace elements.

[0211] Figure 26 is a graph comparing the yield of radish in each treatment area. The vertical axis shows the yield of radish (fresh weight (g)), the horizontal axis shows the treatment area, the bars show the standard deviation, and different letters indicate significant differences at the 5% significance level (n=3). The yield of radish in the treatment area where cedar extract was added was significantly higher than in the control area (Figure 26). In the control area, growth impairment caused the leaves to yellow, which is thought to have reduced chlorophyll content and photosynthetic capacity, resulting in a decrease in yield.

[0212] Thus, by planting root vegetables with Asteraceae plants and adding polyphenol-containing plant extracts to the culture solution, sufficient yields can be obtained even for root vegetables, which have traditionally been considered difficult to grow hydroponically. This demonstrates that the present embodiment can be applied to a variety of crops, not just leafy vegetables, which have traditionally been grown hydroponically. Furthermore, the technology of the present embodiment is an environmentally friendly, fully recirculating hydroponic cultivation method that does not require strict management of the culture solution or expensive sterilization equipment or chemicals, making it a groundbreaking technology that can widely popularize hydroponic cultivation.

[0213] (Example 11) Mixed cultivation of Asteraceae plants and root vegetables using extracts from various polyphenol-containing plants In a greenhouse, radish (Brassicaceae) and lettuce (Asteraceae) seedlings were planted together in a commercially available hydroponic cultivation device shown in Figures 27 and 28, and hydroponic cultivation was carried out with the addition of extracts from various polyphenol-containing plants. Two varieties of radish were used: Akanaga and Shiranaga. Figure 27 is a plan view of the hydroponic cultivation device, and Figure 28 is a side view of the hydroponic cultivation device.

[0214] (1) Preparation of plant extract and trace element mixture The polyphenol-containing plant extracts used were mugwort leaves and stems, radish leaves and stems, lemon balm leaves and stems, mulberry leaves and stems, sage leaves and stems, peppermint leaves and stems, mustard leaves and stems, Satsuma mandarin peel, eucalyptus leaves and stems, and bamboo leaves and stems. Ten grams (dry weight) of each of the polyphenol-containing plant extracts listed above and 700 mL of distilled water were placed in a 1000 mL beaker and heated at 120°C under pressure for 20 minutes. The extract was then filtered through filter paper to obtain a polyphenol-containing plant extract.

[0215] Powdered trace element compounds (boric acid 3g, manganese(II) sulfate 2g, zinc sulfate 0.22g, copper sulfate 0.05g, sodium molybdate 0.01g, iron(II) sulfate 15g) were added to the obtained polyphenol-containing plant extract and dissolved by stirring. Distilled water was added to this to make 1 L, and a plant extract trace element mixture (stock solution) was obtained.

[0216] (2)Cultivation method In each treatment area, as shown in Figures 27 and 28, radishes (one each of the Akanaga and Shiranaga varieties) were planted in two of the four cultivation pipes in the hydroponic cultivation device, and lettuce was planted in the remaining two, with the radishes and lettuce cultivation pipes arranged alternately. A pump was used to flow the nutrient solution in one direction from the nutrient solution tank to the cultivation pipes, then back to the nutrient solution tank, performing a fully circulating hydroponic cultivation system without replacing (discarding) the nutrient solution. Furthermore, no solid medium such as rock wool was used, and the pH and EC of the nutrient solution were not controlled. A float system automatically replenished water without using electricity, maintaining the nutrient solution volume at 15 L.

[0217] A commercially available liquid fertilizer (Hyponex (registered trademark) concentrate, diluted 3000 times, manufactured by Hyponex Japan Co., Ltd.) was used as the culture solution. 5 mL of the mixture of trace elements from various plant extracts (concentrate) prepared in (1) above was diluted 3000 times with this culture solution, and hydroponic cultivation was started using the diluted mixture.

[0218] Starting one week after the start of cultivation, 15 mL (1000-fold dilution) of the above-mentioned plant extract trace element mixture (stock solution) and 5 mL (3000-fold dilution) of "Hyponex (registered trademark) stock solution" were added to 15 L of culture medium at 7-day intervals.

[0219] After harvesting, the yield of radish was measured. As a control, hydroponic cultivation was carried out in the same manner as above, except that a commercially available liquid fertilizer was used instead of the plant extract trace element mixture.

[0220] (3) Results and Discussion The results are shown in Figures 29 and 30. Figure 29 is a photograph showing the state of mixed cultivation in the areas where various plant extracts were added and the control area. The radishes in the control area suffered growth disorders (yellowing of leaves), whereas the plants in the plant extract-added area did not suffer growth disorders and grew healthily. It is thought that the growth disorders in the control area were caused by the secretion of allelopathic substances (autointoxication).

[0221] Figure 30 is a graph comparing the yield of (a) red radish and (b) white radish in each treatment area. The vertical axis represents fresh weight (g) per plant, the horizontal axis represents treatment area, the bars represent standard deviation, and different letters indicate significant differences at the 5% significance level (n=9). The yield of radish in the treatment area where extracts of various polyphenol-containing plants were added was higher than in the control area (Figure 30). In the control area, yellowing of the leaves due to growth impairment is thought to have resulted in a decrease in chlorophyll content and a decrease in photosynthetic capacity, resulting in a decrease in yield.

[0222] A phenomenon known as "autointoxication" occurs when allelopathic substances exuded from plant roots accumulate in high concentrations in the culture solution, causing growth disorders. In this example, the growth disorders that occurred in the control area are believed to be due to the allelopathic substances. On the other hand, in the plant extract-added area, the polyphenol-iron complex in the culture solution reacted with hydrogen peroxide secreted by Asteraceae plants to generate hydroxyl radicals, which decomposed and removed the organic allelopathic substances, and therefore no growth disorders occurred. Therefore, the hydroponic cultivation method of this embodiment enables stable crop production even with a completely recycled system that eliminates wastewater.

[0223] (Example 12) Hydroponic cultivation of Lamiaceae plants using rosemary and oregano extracts In a greenhouse, perilla (Lamiaceae) seedlings were planted in a commercially available hydroponic cultivation device, and hydroponic cultivation was carried out with the addition of rosemary extract or oregano extract.

[0224] (1) Preparation of plant extract and trace element mixture Rosemary leaves and stems and oregano (whole plant) were used as polyphenol-containing plants. 10 g (dry weight) of each polyphenol-containing plant was placed in a 1000 mL beaker and heated at 120°C for 20 minutes under pressure. The resulting solution was filtered through a paper filter to obtain a polyphenol-containing plant extract.

[0225] Powdered trace element compounds (boric acid 3g, manganese(II) sulfate 2g, zinc sulfate 0.22g, copper sulfate 0.05g, sodium molybdate 0.01g, iron(II) sulfate 15g) were added to the obtained polyphenol-containing plant extract and dissolved by stirring. Distilled water was added to this to make 1 L, and a plant extract trace element mixture (stock solution) was obtained.

[0226] (2)Cultivation method In each treatment area, perilla plants were planted in a hydroponic cultivation system as shown in Figure 31 and grown hydroponically. A pump was used to flow the nutrient solution in one direction from the nutrient solution tank to the cultivation pipe, and then the solution was returned to the nutrient solution tank. This was a fully circulating hydroponic cultivation system, with no need to replace (discard) the nutrient solution. In addition, no solid medium such as rock wool was used, and the pH and EC of the nutrient solution were not controlled. A float system was used to automatically replenish water without using electricity, maintaining the nutrient solution volume at 15 L.

[0227] A commercially available liquid fertilizer (Hyponex (registered trademark) concentrate, diluted 3000 times, manufactured by Hyponex Japan Co., Ltd.) was used as the culture solution. 5 mL of the mixture of trace elements from various plant extracts (concentrate) prepared in (1) above was diluted 3000 times with this culture solution, and hydroponic cultivation was started using the diluted mixture.

[0228] Starting one week after the start of cultivation, 15 mL (1000-fold dilution) of the above-mentioned plant extract trace element mixture (stock solution) and 5 mL (3000-fold dilution) of "Hyponex (registered trademark) stock solution" were added to 15 L of culture medium at 7-day intervals.

[0229] The height of the perilla plants was measured 21 days after planting. As a control, hydroponic cultivation was carried out in the same manner as above, except that a commercially available liquid fertilizer was used instead of the plant extract trace element mixture.

[0230] (3) Results and Discussion The results are shown in Figures 31 and 32. Figure 31 is a photograph showing the state of hydroponic cultivation in the areas where various plant extracts were added and in the control area. The perilla plants in the control area turned yellow, whereas the plants in the plant extract-added area grew healthily. It is believed that growth impairment occurred in the control area due to autointoxication.

[0231] Figure 32 is a graph comparing the plant height of each treatment area. The vertical axis shows the shiso plant height, the horizontal axis shows the treatment area, and the bars show the standard deviation, with different letters indicating significant differences at the 5% significance level (n=18). The shiso plant height in the treatment area where extracts of various polyphenol-containing plants were added was significantly (p<0.05) higher than in the control area (Figure 32). It is thought that growth was impaired in the control area due to autointoxication, resulting in poor growth.

[0232] Hydrogen peroxide exuded from the roots of Lamiaceae plants and polyphenol-iron complexes undergo a Fenton reaction in the culture solution, enabling disease control and suppression of autointoxication. Furthermore, plant extract trace element complexes other than polyphenol-iron complexes also have antibacterial properties, resulting in even more powerful disease control effects. Furthermore, because the plant extract trace element complexes help plants absorb trace elements, trace element deficiency symptoms do not occur even without pH control.

[0233] (Example 13) Mixed cultivation of Lamiaceae plants and leafy vegetables using oregano and rosemary extracts In a greenhouse, seedlings of perilla (Lamiaceae) and spinach (Amaranthaceae) were planted in a commercially available hydroponic cultivation device shown in FIG. 33, and hydroponic cultivation was carried out with the addition of oregano and rosemary extracts.

[0234] (1) Preparation of plant extract and trace element mixture The polyphenol-containing plant extracts used were oregano leaves and stems and rosemary leaves and stems. 10 g (dry weight) of the polyphenol-containing plant extracts and 700 mL of distilled water were placed in a 1000 mL beaker and heated at 120°C under pressure for 20 minutes. These extracts were used as various polyphenol-containing plant extracts.

[0235] Powdered trace element compounds (boric acid 3g, manganese(II) sulfate 2g, zinc sulfate 0.22g, copper sulfate 0.05g, sodium molybdate 0.01g, iron(II) sulfate 15g) were added to the obtained polyphenol-containing plant extract and dissolved by stirring. Distilled water was added to this to make 1 L, and a plant extract trace element mixture (stock solution) was obtained.

[0236] (2)Cultivation method In each treatment area, perilla and spinach were planted in a hydroponic cultivation system as shown in Figure 33 and grown hydroponically. A pump was used to flow the nutrient solution in one direction from the nutrient solution tank to the cultivation pipe, and then the solution was returned to the nutrient solution tank. This was a fully circulating hydroponic cultivation system, with no nutrient solution replacement (disposal). Furthermore, no solid medium such as rock wool was used, and the pH and EC of the nutrient solution were not controlled. A float system was used to automatically replenish water without using electricity, maintaining the nutrient solution volume at 15 L.

[0237] A commercially available liquid fertilizer (Hyponex (registered trademark) concentrate, diluted 3000 times, manufactured by Hyponex Japan Co., Ltd.) was used as the culture solution. 5 mL of the plant extract trace element mixture (concentrate) prepared in (1) above was diluted 3000 times with this culture solution, and hydroponic cultivation was started using the diluted solution.

[0238] Starting one week after the start of cultivation, 15 mL (1000-fold dilution) of the above-mentioned plant extract trace element mixture (stock solution) and 5 mL (3000-fold dilution) of "Hyponex (registered trademark) stock solution" were added to 15 L of culture medium at 7-day intervals.

[0239] Twenty-one days after planting, the height of the perilla plants and the chlorophyll content of the spinach plants were measured. The chlorophyll content was measured by measuring leaf color (SPAD value) using a chlorophyll meter. As a control, hydroponic cultivation was performed in the same manner as above, except that a commercially available liquid fertilizer was used instead of the plant extract trace element mixture.

[0240] (3) Results and Discussion The results are shown in Figures 33 and 34. Figure 33 is a photograph showing the state of mixed cultivation in the oregano and rosemary extract-added area and the control area. Although it is difficult to see from Figure 33, yellowing of the spinach plants was observed in the control area, whereas the spinach plants in the oregano and rosemary extract-added area grew healthily. It is thought that the spinach plants in the control area suffered growth disorders (especially yellowing of young leaves due to iron deficiency) due to an imbalance in the nutrient solution composition.

[0241] Figure 34 is a graph showing the effect of adding rosemary extract and oregano extract on the growth of perilla and spinach. Figure 34(a) is a graph comparing the height of perilla plants in each treatment area. The vertical axis represents perilla plant height (cm), the horizontal axis represents treatment area, the bars represent standard deviation, and different letters indicate significant differences at the 5% significance level (n=18). The height of perilla plants in the treatment area to which oregano and rosemary extracts were added was significantly higher than in the control area (Figure 34(a)). A similar trend was observed for spinach plant height. It is believed that the poor growth in the control area was due to autointoxication and growth impairment caused by an imbalance in the nutrient solution composition.

[0242] Figure 34(b) is a graph comparing the chlorophyll content of spinach leaves in each treatment group. The vertical axis represents leaf chlorophyll content (SPAD value), the horizontal axis represents treatment group, and the bars represent standard deviation, with different letters indicating significant differences at the 5% significance level (n=18). The chlorophyll content of spinach in the treatment group to which oregano and rosemary extracts were added was significantly higher than in the control group (Figure 34(b)). As shown in Figure 33, in the control group, an imbalance in the nutrient solution composition caused a deficiency of trace elements (especially iron), which likely led to a decrease in chlorophyll content and the yellowing of the plants.

[0243] It has been shown that fully recirculating hydroponic cultivation of spinach is possible by planting it together with Lamiaceae plants and adding polyphenol-containing plant extracts to the nutrient solution. Hydrogen peroxide exuded from the Lamiaceae roots and polyphenol-iron complexes undergo a Fenton reaction, enabling disease control and suppression of autointoxication. Furthermore, trace element complexes of plant extracts other than polyphenol-iron complexes promote disease control and trace element absorption by the plant.

[0244] (Test Example 4) Antibacterial test using plant extract trace element complex The antibacterial activity of plant extract-trace element complexes, which are reaction products of various polyphenol-containing plant extracts and trace elements, against Escherichia coli was examined.

[0245] (1) Preparation of plant extract trace element complex Plants containing polyphenols include acacia leaves and stems, grape pomace (the residue produced during the wine-making process), poplar leaves and stems, lemon balm (whole plant), banana leaves and stems, ginkgo leaves and stems, cacao leaves and stems, cedar leaves and stems, pine leaves and stems, perilla leaves and stems, yuzu fruit, coffee tree leaves and stems, persimmon leaves and stems, oregano (whole plant), mustard leaves and stems, chrysanthemum flowers, guava leaves and stems, mulberry leaves and stems, The following materials were used: sweet potato leaves, petioles and vines, sage (whole plant), radish leaves and stems, bamboo leaves and stems, bamboo skin (bamboo shoot skin), papaya leaves and stems, cypress skin, cypress leaves and stems, peppermint leaves and stems, mango leaves and stems, Satsuma mandarin peel, willow leaves and stems, eucalyptus leaves and stems, mugwort leaves and stems, lavender leaves and stems, rosemary leaves and stems, lemon leaves and stems, tea leaves (green tea), and sugarcane leaves and stems.

[0246] Ten grams (dry weight) of these polyphenol-containing plants were placed in a 1000 mL beaker, 700 mL of distilled water was added, and the mixture was heated under pressure at 120°C for 20 minutes. The mixture was filtered through a paper filter to obtain a polyphenol-containing plant extract. Powdered trace element compounds (3 g of boric acid, 2 g of manganese(II) sulfate, 0.22 g of zinc sulfate, 0.05 g of copper sulfate, 0.01 g of sodium molybdate, and 15 g of iron(II) sulfate) were added to the extract, mixed, and reacted to obtain a reaction product (plant extract trace element complex solution).

[0247] (2) Antibacterial evaluation test The antibacterial activity evaluation method is shown in Figure 35. First, 100 μL (1 × 10 6 cfu / mL) was spread on LB agar medium (Figure 35(a)). Next, a paper disk containing the plant extract trace element complex solution obtained above was placed on the LB agar medium and cultured overnight at 37°C (Figure 35(b)). The antibacterial activity of the polyphenol-iron complex was determined based on the presence or absence of a bacterial growth inhibition halo around the paper disk (Figure 35(c)). A control group was treated in the same manner as above, except that no polyphenol-containing plant material was used.

[0248] (3) Results and Discussion The results are shown in Figures 36 to 42. In Figure 36, (a) represents the control, (b) represents the acacia extract trace element complex, (c) represents the grape extract trace element complex, (d) represents the poplar extract trace element complex, (e) represents the lemon balm extract trace element complex, and (f) represents the banana extract trace element complex. In Figure 37, (g) represents the ginkgo extract trace element complex, (h) represents the cacao extract trace element complex, (i) represents the cedar extract trace element complex, (k) represents the pine extract trace element complex, (m) represents the perilla extract trace element complex, and (n) represents the yuzu extract trace element complex. In Figure 38, (o) represents the coffee extract trace element complex, (p) represents the persimmon extract trace element complex, (q) represents the oregano extract trace element complex, (r) represents the mustard extract trace element complex, (s) represents the chrysanthemum extract trace element complex, and (t) represents the guava extract trace element complex. In Figure 39, (u) represents the mulberry extract trace element complex, (v) represents the sweet potato extract trace element complex, (w) represents the sage extract trace element complex, (x) represents the radish extract trace element complex, (y) represents the bamboo leaf extract trace element complex, and (z) represents the bamboo bark extract trace element complex. In Figure 40, (a') represents the papaya extract trace element complex, (b') represents the cypress bark extract trace element complex, (c') represents the cypress leaf extract trace element complex, (d') represents the peppermint extract trace element complex, (e') represents the mango extract trace element complex, and (f') represents the mandarin orange extract trace element complex. In Figure 41, (g') represents the willow extract trace element complex, (h') represents the eucalyptus extract trace element complex, (i') represents the mugwort extract trace element complex, (k') represents the lavender extract trace element complex, (m') represents the rosemary extract trace element complex, and (n') represents the lemon extract trace element complex. In Figure 42, (o') represents the tea extract trace element complex, and (p') represents the sugarcane extract trace element complex.

[0249] 36 to 42 show that all plant extract trace element complexes have antibacterial activity against E. coli. Therefore, it was found that by reacting various polyphenol-containing plant extracts with trace elements, plant extract trace element complexes with excellent antibacterial activity can be obtained. This demonstrates that in this embodiment, by adding extracts from various plants to a culture solution and incorporating a plant extract trace element complex into the culture solution, it is possible to kill or inhibit the growth of pathogenic microorganisms.

[0250] (Test Example 5) Antibacterial test using polyphenol iron complex and chrysanthemum root The antibacterial activity against Escherichia coli was examined when a polyphenol iron complex was used in combination with hydrogen peroxide from chrysanthemum root.

[0251] (1) Preparation of polyphenol-iron complex A polyphenol-iron complex was prepared using tea leaves (green tea) as the polyphenol-containing plant material. 10 g of dried tea leaves were placed in a 1000 mL beaker, 700 mL of distilled water was added, and the mixture was heated at 120°C under pressure for 20 minutes. The mixture was filtered through a paper filter to obtain a polyphenol extract. 8.8 g of iron(III) chloride (3 g of elemental iron) was added to the extract, mixed, and reacted to obtain the reaction product (polyphenol-iron complex solution).

[0252] (2) Antibacterial evaluation test The E. coli strain tested was O157:H7 (ATCC43888). The following two treatment groups were set up.

[0253] Chrysanthemum root only treatment group (control): 100 mL (1.2 × 10 6 cfu / mL) was placed in a 200 mL beaker, and one chrysanthemum seedling (root part) was immersed therein. Chrysanthemum root and polyphenol-iron complex treatment group: 100 μL of the above polyphenol-iron complex solution and 100 mL (1.2 × 10 6 cfu / mL) was placed in a 200 mL beaker, and one chrysanthemum seedling (root part) was immersed therein.

[0254] Chrysanthemum roots were immersed in visible light (490-660 nm) for 24 hours. To determine the viability of E. coli, 100 μL of bacterial solution was collected from each treatment group, spread onto LB agar medium, and cultured at 37°C for 24 hours.

[0255] (3) Results and Discussion The results are shown in Figure 43. In Figure 43, (a) shows the area treated with chrysanthemum roots only (control), and (b) shows the area treated with chrysanthemum roots and a polyphenol-iron complex. As a result, E. coli survived in the area treated with chrysanthemum roots only, whereas most of the E. coli was killed in the area treated with chrysanthemum roots and a polyphenol-iron complex (Figure 43).

[0256] It is thought that hydrogen peroxide exuded from chrysanthemum roots reacts with the polyphenol-iron complex to cause the Fenton reaction, resulting in a powerful bactericidal effect from hydroxyl radicals. Furthermore, since the polyphenol-iron complex has visible light-responsive photocatalytic activity, it is thought that the photocatalytic activity also exerts a bactericidal effect when irradiated with visible light.

[0257] From the above, it was suggested that the combination of cultivation of Asteraceae plants with a culture solution containing a polyphenol-containing plant extract, and further the combination of this with light irradiation of the culture solution, can provide excellent effects of killing or inhibiting the growth of pathogenic microorganisms.

[0258] (Test Example 6) Antibacterial comparative test The antibacterial activity against Escherichia coli was compared between tea leaf extract as an extract of a polyphenol-containing plant body, trace elements, and the reaction product thereof, a tea extract-trace element complex.

[0259] (1) Sample preparation method Preparation of tea leaf extract trace element complex solution: 10 g of dried tea leaves (green tea) were placed in a 1000 mL beaker, 700 mL of distilled water was added, and the mixture was heated under pressure at 120°C for 20 minutes. Powdered trace element compounds (boric acid 3 g, manganese(II) sulfate 2 g, zinc sulfate 0.22 g, copper sulfate 0.05 g, sodium molybdate 0.01 g, and iron(II) sulfate 15 g) were added and mixed. Distilled water was added to this mixture to make a 1000 mL solution, creating a tea leaf extract trace element complex solution.

[0260] Preparation of tea leaf extract: 10 g of dried tea leaves (green tea) were placed in a 1000 mL beaker, 700 mL of distilled water was added, and the mixture was heated under pressure at 120°C for 20 minutes. Distilled water was then added to the mixture to make a total of 1000 mL, which was used as a tea leaf extract.

[0261] Preparation of trace element mixture: In a 1000 mL beaker, 700 mL of distilled water and powdered trace element compounds (boric acid 3 g, manganese (II) sulfate 2 g, zinc sulfate 0.22 g, copper sulfate 0.05 g, sodium molybdate 0.01 g, iron (II) sulfate 15 g) were added and mixed. Distilled water was added to this to make a 1000 mL solution, which was used as a trace element mixture.

[0262] (2) Antibacterial evaluation method The antibacterial evaluation test using the paper disc method was carried out in the same manner as in Figure 35 (Test Example 4). That is, 100 µL (2.5 × 10) of Escherichia coli O157:H7 (ATCC43888) pre-cultured in LB liquid medium (37 °C, 24 hours) was used. 6 cfu / mL) was inoculated onto LB agar medium to prepare plate media. Paper discs (for antibiotic testing, manufactured by Advantec Toyo Co., Ltd., diameter 8 mm) containing each sample prepared in (1) above were placed on the plate media and cultured at 37°C for 24 hours. After the culture was completed, the diameters (two points, x and y) of the bacterial growth inhibition halos that appeared around the paper discs were measured (Figure 44). As a control, paper discs containing distilled water instead of each sample were used, and the test was conducted in the same manner as above for comparison.

[0263] (3) Results and Discussion The results are shown in Table 3. Table 3 shows the results of the antibacterial test using the paper disc method (n=3). In Table 3, the numbers indicate the diameter of the bacterial growth inhibition halo in each treatment area (average values ​​of x and y in Figure 44, unit: mm), and different letters indicate significant differences at the 5% significance level.

[0264] [Table 3] (-): No blocking halo formation

[0265] While no inhibitory halo formation was observed in the control group, inhibitory halos were observed in the treatment groups treated with the trace element mixture, tea leaf extract, and tea leaf extract trace element complex solution (Table 3). The diameters (average x and y) of the inhibitory halos formed with the trace element mixture alone and the tea leaf extract alone were 18.4 and 17.9 mm, respectively. The tea leaf extract trace element complex solution formed a significantly larger inhibitory halo with a diameter (same as above) of 33.7 mm (Table 3). These results demonstrate that the reaction product, the plant extract trace element complex, exhibits significantly greater antibacterial activity than the plant extract alone or the trace elements alone. This is thought to be due to a synergistic effect between the components contained in the plant extract and the trace elements.

[0266] (Test Example 7) Comparative antibacterial activity test of polyphenol iron complex and plant extract trace element complex Polyphenol-iron complexes and plant extract trace element complexes containing 5.4 mM or 54 mM iron were prepared and their antibacterial activity against Escherichia coli was compared.

[0267] (1) Sample preparation method Preparation of tea leaf extract trace element complex solution: 10 g of dried tea leaves (green tea) were placed in a 1000 mL beaker, 700 mL of distilled water was added, and the mixture was heated under pressure at 120 °C for 20 minutes. Powdered trace element compounds (3 g of boric acid, 2 g of manganese(II) sulfate, 0.22 g of zinc sulfate, 0.05 g of copper sulfate, 0.01 g of sodium molybdate, and 15 g of iron(II) sulfate) were added and mixed. Distilled water was added to the mixture to make a 1000 mL solution, creating a tea leaf extract trace element complex solution (54 mM iron). A tea leaf extract trace element complex solution (5.4 mM iron) was also prepared in the same manner as above, except that the amount of each trace element compound added was reduced to one-tenth of the original amount.

[0268] Preparation of polyphenol-iron complex: 10 g of dried tea leaves (green tea) were placed in a 1000 mL beaker, 700 mL of distilled water was added, and the mixture was heated under pressure at 120°C for 20 minutes. 15 g of powdered iron(II) sulfate was added and mixed, and further distilled water was added to bring the total volume to 1000 mL to prepare a polyphenol-iron complex solution (54 mM iron). A polyphenol-iron complex solution (5.4 mM iron) was also prepared in the same manner as above, except that 1.5 g of iron(II) sulfate was added.

[0269] (2) Antibacterial evaluation method The antibacterial evaluation test by the paper disc method was carried out in the same manner as in Test Example 6. That is, 100 μL (2.5 × 10 6 cfu / mL) was inoculated onto LB agar medium to prepare plate media. Paper discs (for antibiotic testing, manufactured by Advantec Toyo Co., Ltd., diameter 8 mm) containing each sample prepared in (1) above were placed on the plate media and cultured at 37°C for 24 hours. After the culture was completed, the diameters (two points, x and y) of the bacterial growth inhibition halos that appeared around the paper discs were measured (Figure 44). As a control, paper discs containing distilled water instead of each sample were used, and the test was conducted in the same manner as above for comparison.

[0270] (3) Results and Discussion The results are shown in Table 4. Table 4 shows the results of the antibacterial test using the paper disc method (n=3). In Table 4, the numbers indicate the diameter of the bacterial growth inhibition halo in each treatment area (average values ​​of x and y in Figure 41, unit: mm), and different letters indicate significant differences at the 5% significance level.

[0271] [Table 4] (-): No blocking halo formation

[0272] At 5.4 mM iron, no inhibition halo was observed in the control or polyphenol-iron complex groups, whereas an inhibition halo was observed in the tea leaf extract trace element complex group (Table 4, top). At 54 mM iron, inhibition haloes were observed in both the tea leaf extract trace element complex group and the polyphenol-iron complex group, but a significantly larger inhibition halo was formed in the tea leaf extract trace element complex group than in the polyphenol-iron complex group (Table 4, bottom). These results demonstrate that even at high concentrations, the plant extract trace element complex exhibits stronger antibacterial activity than the polyphenol-iron complex.

[0273] The tea leaf extract trace element complex solution used in this example, with an iron concentration of 54 mM, has the same concentration as the plant extract trace element mixture solution (stock solution) prepared using tea leaf extract in Preparation Example 1. Therefore, it is clear that adding the plant extract trace element mixture solution to the culture solution provides significantly better disease control effects than conventional polyphenol-iron complexes.

[0274] (Test Example 8) Detection of hydrogen peroxide in the roots of various Lamiaceae plants To confirm that hydrogen peroxide is secreted from the roots of various Lamiaceae plants, the hydrogen peroxide concentration on the root surface was measured. The Lamiaceae plants used were lemon balm, basil, rosemary, mojito mint, pennyroyal mint, and oregano.

[0275] The above-mentioned various Lamiaceae plants were hydroponically grown, and the hydrogen peroxide concentration in the water attached to the root surface was measured using hydrogen peroxide test paper (Merck). As a result, hydrogen peroxide levels of 100 mg / L or more were detected in all Lamiaceae plants.

[0276] High concentrations of hydrogen peroxide were also detected in the roots of Lamiaceae plants other than mint, suggesting that hydrogen peroxide is exuded from the roots of Lamiaceae plants in general.

[0277] (Example 14) Mixed cultivation of Lamiaceae plants using oregano extract In a greenhouse, basil (Lamiaceae) and lettuce (Asteraceae) or parsley (Apiaceae) seedlings were planted in a commercially available hydroponic cultivation device, and mixed cultivation was performed with the addition of oregano extract.

[0278] (1) Preparation of plant extract and trace element mixture The polyphenol-containing plant extract was prepared from the leaves and stems of oregano. 10 g (dry weight) of oregano and 700 mL of distilled water were placed in a 1000 mL beaker and heated at 120°C under pressure for 20 minutes. The supernatant was filtered to obtain a polyphenol-containing plant extract.

[0279] Powdered trace element compounds (boric acid 3g, manganese(II) sulfate 2g, zinc sulfate 0.22g, copper sulfate 0.05g, sodium molybdate 0.01g, iron(II) sulfate 15g) were added to the obtained polyphenol-containing plant extract and dissolved by stirring. Distilled water was added to this to make 1 L, and a plant extract trace element mixture (stock solution) was obtained.

[0280] (2)Cultivation method In each treatment area, basil and lettuce (Figure 45) or basil and parsley (Figure 47) were planted in the hydroponic cultivation device and grown hydroponically. As shown in Figures 45 and 47, basil was planted in two of the four cultivation pipes in the hydroponic cultivation device, and lettuce or parsley was planted in the remaining two, with the basil and lettuce or parsley cultivation pipes arranged alternately. A commercially available liquid fertilizer ("OAT House" Formulation A, manufactured by OAT Agrio) was used as the nutrient solution. No solid medium such as rock wool was used, and the pH and EC of the nutrient solution were not controlled. A float system automatically replenished water without using electricity to maintain the nutrient solution volume.

[0281] In the oregano extract treatment group, hydroponic cultivation was performed using the plant extract trace element mixture (stock solution) prepared in (1) above, diluted 1000-fold with the same culture solution. The culture solution was pumped in one direction from the culture solution tank to the cultivation pipe, then returned to the culture solution tank. This complete circulation hydroponic cultivation method did not require replacement (disposal) of the culture solution. Starting one week after the start of cultivation, 15 mL (1000-fold dilution) of the plant extract trace element mixture (stock solution) was added to 15 L of culture solution at 7-day intervals.

[0282] After harvesting, the yield of each crop was measured. As a control without oregano extract, the following non-exchanged and exchanged plots were set up for comparison.

[0283] Non-exchange group: In the same way as the oregano extract treatment group, a fully circulating hydroponic culture system was used, without changing the nutrient solution, except that a commercially available liquid fertilizer was used instead of the plant extract trace element mixture (undiluted solution). Replacement group: One week after the start of cultivation, the entire culture medium was replaced with new culture medium at 7-day intervals.

[0284] (3) Results and Discussion The results are shown in Figures 45 to 48. Figures 45 and 47 are photographs showing the mixed cultivation of basil and lettuce, and basil and parsley, respectively. Compared to the non-exchange area and the exchange area, the growth of each crop was promoted in the oregano extract-added area (Figures 45 and 47).

[0285] Figure 46 is a graph comparing the yield of (a) basil and (b) lettuce in each treatment area. The vertical axis is fresh weight (g) per stalk, the horizontal axis is treatment area, the bars indicate standard deviation, and different letters indicate significant differences at the 5% significance level (n=18). Figure 48 is a graph comparing the yield of (a) basil and (b) parsley in each treatment area. The vertical axis is fresh weight (g) per stalk, the horizontal axis is treatment area, the bars indicate standard deviation, and different letters indicate significant differences at the 5% significance level (n=18).

[0286] In mixed plantings of basil and lettuce, and basil and parsley, each crop grew healthily in both treatment areas. This demonstrated that fully recirculating hydroponic cultivation is possible when plants are planted in mixed cultivation with Lamiaceae plants, even without adding a plant extract trace nutrient mixture (Figures 45 and 47). In the oregano extract-added area, the yield of each crop was significantly higher than in the control non-exchange and exchange areas. This demonstrated that adding a plant extract trace nutrient mixture promotes plant growth (Figures 46 and 48).

[0287] Furthermore, hydrogen peroxide was detected in the roots of basil in Test Example 8. It is believed that hydrogen peroxide exuded from the basil roots reacts with the polyphenol-iron complex in the culture solution to cause a Fenton reaction, resulting in a powerful bactericidal effect due to hydroxyl radicals.

[0288] (Example 15) Mixed cultivation of Lamiaceae plants and root vegetables using rosemary and thyme extracts In a greenhouse, various Lamiaceae plants and radish (Brassicaceae) seedlings were planted in a commercially available hydroponic cultivation device, and mixed cultivation was carried out with the addition of rosemary extract or thyme extract.

[0289] (1) Preparation of plant extract and trace element mixture The leaves and stems of rosemary and thyme were used as polyphenol-containing plant materials. 10 g (dry weight) of polyphenol-containing plant materials and 700 mL of distilled water were placed in a 1000 mL beaker and heated at 120°C under pressure for 20 minutes. The supernatant was filtered to obtain a polyphenol-containing plant extract.

[0290] Powdered trace element compounds (boric acid 3g, manganese(II) sulfate 2g, zinc sulfate 0.22g, copper sulfate 0.05g, sodium molybdate 0.01g, iron(II) sulfate 15g) were added to the obtained polyphenol-containing plant extract and dissolved by stirring. Distilled water was added to this to make 1 L, and a plant extract trace element mixture (stock solution) was obtained.

[0291] (2)Cultivation method In each treatment area, oregano and daikon radish (Figure 49), rosemary and daikon radish (Figure 51), lemon balm and daikon radish (Figure 53), and mojito mint and daikon radish (Figure 55) were planted in the hydroponic cultivation device and grown hydroponically. As shown in these figures, a mint family plant was planted in one of the four cultivation pipes of the hydroponic cultivation device, and daikon radish was planted in the remaining three cultivation pipes. A commercially available liquid fertilizer ("OAT House" Formulation A, manufactured by OAT Agrio) was used as the nutrient solution. No solid medium such as rock wool was used, and the pH and EC of the nutrient solution were not controlled. A float system automatically replenished water without using electricity to maintain the nutrient solution volume.

[0292] In the plant extract-added group, hydroponic cultivation was performed using the plant extract trace element mixture (stock solution) prepared in (1) above, diluted 1000-fold with the same culture solution. For the mixed cultivation of mint and daikon radish (Figure 55), a plant extract trace element mixture (stock solution) supplemented with thyme extract was used. For other mixed cultivations, a plant extract trace element mixture (stock solution) supplemented with rosemary extract was used. A pump was used to flow the culture solution in one direction from the culture solution tank to the cultivation pipe, and then the solution was returned to the culture solution tank. A complete circulation hydroponic cultivation was performed, with no replacement (discarding) of the culture solution. Starting one week after the start of cultivation, 15 mL (1000-fold dilution) of the above-mentioned plant extract trace element mixture (stock solution) was added to 15 L of culture solution at 7-day intervals.

[0293] After harvesting, the yield of each crop was measured. As a control without the addition of the plant extract, the following non-exchanged and exchanged plots were set up for comparison.

[0294] Non-exchange group: In the same way as in the plant extract treatment group, except that a commercially available liquid fertilizer was used instead of the plant extract trace element mixture (undiluted solution), a fully circulating hydroponic culture method was used in which the nutrient solution was not exchanged. Replacement group: One week after the start of cultivation, the entire culture medium was replaced with new culture medium at 7-day intervals.

[0295] (3) Results and Discussion The results are shown in Figures 49 to 56. Figures 49, 51, 53, and 55 are photographs showing the mixed cultivation of various Labiatae plants and radish. In all cultivation tests, the growth of each crop was promoted in the areas where rosemary or thyme extract was added compared to the non-exchange and exchange areas (Figures 49, 51, 53, and 55).

[0296] Figure 50 is a graph comparing the yields of (a) radish and (b) oregano in each treatment area. Figure 52 is a graph comparing the yields of (a) radish and (b) rosemary in each treatment area. Figure 54 is a graph comparing the yields of (a) radish and (b) lemon balm in each treatment area. Figure 56 is a graph comparing the yields of (a) radish and (b) mint in each treatment area. In each of these figures, the vertical axis is fresh weight (g) per plant, the horizontal axis is treatment area, the bars indicate standard deviation, and different letters indicate significant differences at the 5% significance level (n=9).

[0297] When radish was cultivated in mixed cultivation with various Lamiaceae plants, each crop grew healthily in all treatment areas. This demonstrated that fully recirculating hydroponic cultivation is possible when mixed cultivation with Lamiaceae plants, even without adding a plant extract trace nutrient mixture (Figures 49, 51, 53, and 55). In the areas where rosemary or thyme plant extract was added, the yield of each crop was significantly higher than in the control non-exchange and exchange areas. It was demonstrated that the addition of a plant extract trace nutrient mixture promoted plant growth (Figures 50, 52, 54, and 56).

[0298] Furthermore, hydrogen peroxide was detected in the roots of the Lamiaceae plants used in Test Example 8. It is believed that hydrogen peroxide exuded from the roots of Lamiaceae plants in general reacts with the polyphenol-iron complex in the culture solution to cause a Fenton reaction, resulting in a powerful bactericidal effect due to hydroxyl radicals.

[0299] (Example 16) Mixed cultivation of Asteraceae or Lamiaceae plants and fruit vegetables using rosemary and basil extracts In a greenhouse, seedlings of chrysanthemum or basil (Lamiaceae) and tomato (Solanaceae) were planted in the hydroponic cultivation device shown in Figures 57 and 58, and mixed cultivation was carried out by adding rosemary extract or basil extract.

[0300] (1) Preparation of plant extract and trace element mixture The polyphenol-containing plant extracts used were rosemary and basil leaves and stems. 10 g (dry weight) of polyphenol-containing plant material and 700 mL of distilled water were placed in a 1000 mL beaker and heated at 120°C under pressure for 20 minutes. The supernatant was filtered to obtain a polyphenol-containing plant extract.

[0301] Powdered trace element compounds (boric acid 3g, manganese(II) sulfate 2g, zinc sulfate 0.22g, copper sulfate 0.05g, sodium molybdate 0.01g, iron(II) sulfate 15g) were added to the obtained polyphenol-containing plant extract and dissolved by stirring. Distilled water was added to this to make 1 L, and a plant extract trace element mixture (stock solution) was obtained.

[0302] (2)Cultivation method Tomatoes alone (Figures 57 and 58(a)), tomatoes and basil (Figures 57 and 58(b)), and tomatoes and chrysanthemums (Figures 57 and 58(c)) were planted in the hydroponic cultivation device and grown hydroponically.

[0303] Figure 57 is a schematic diagram showing the cross section of the hydroponic cultivation device for (a) tomato only cultivation area, (b) tomato-basil mixed cultivation area, and (c) tomato-chrysanthemum mixed cultivation area. Figure 58 is a photographic image showing the state of mixed cultivation at the time of planting in (a) tomato only cultivation area, (b) tomato-basil mixed cultivation area, and (c) tomato-chrysanthemum mixed cultivation area.

[0304] As shown in Figures 57 and 58, the hydroponic cultivation device in the mixed cultivation area consisted of a 10-m-long PVC pipe with an inner diameter of 10 cm, fixed parallel to the cultivation bed above a 10-m-long cultivation bed in which tomato seedlings had been planted, using wires hanging from the ceiling of the greenhouse. Openings were made at regular intervals at the top of the PVC pipe, and basil or chrysanthemum seedlings were planted in these openings. The cultivation bed and the pipe were connected by a hose, and the nutrient solution was circulated between the cultivation bed and the pipe by a pump. In the tomato-only cultivation area, hydroponic cultivation was carried out using only the cultivation bed.

[0305] In all cultivation areas, a pump was used to flow the nutrient solution in one direction from the nutrient solution tank and then return it to the nutrient solution tank, and full circulation hydroponic cultivation was carried out without changing (discarding) the nutrient solution. In the cultivation beds, an air pump was used to supply oxygen to the nutrient solution during cultivation. No solid medium such as rock wool was used, and the pH and EC of the nutrient solution were not managed. A float system was used to automatically replenish water without using electricity, maintaining the amount of nutrient solution.

[0306] A commercially available liquid fertilizer ("OAT House" Formulation A, manufactured by OAT Agrio) was used as the culture solution. In the mixed planting area, hydroponic cultivation was initiated using the plant extract trace element mixture (stock solution) prepared in (1) above, diluted 1000-fold with this culture solution. Starting one week after the start of cultivation, 700 mL (1000-fold dilution) of the plant extract trace element mixture (stock solution) was added to 700 L of culture solution at 7-day intervals.

[0307] In the tomato-basil mixed cultivation area, a plant extract trace element mixture (stock solution) with added basil extract was used. In the tomato-chrysanthemum mixed cultivation area, a plant extract trace element mixture (stock solution) with added rosemary extract was used. As a control, in the tomato-only cultivation area, a commercially available liquid fertilizer was used instead of the plant extract trace element mixture (stock solution).

[0308] After harvest, the total fresh weight of the tomatoes (the sum of fruit, leaves, branches, and stems) and fruit yield were measured. Furthermore, on the 52nd day after the start of cultivation, the bacterial density in the culture solution was measured. The bacterial density was measured by collecting 50 mL of culture solution from three locations in the cultivation bed, inoculating 100 μL of each culture solution sample onto an agar medium, and culturing the solution at 37°C for 48 hours.

[0309] (3) Results and Discussion The results are shown in Figures 59 and 60. Figure 59 is a photograph showing the state of the cultivation test and the effect on the density of contaminating bacteria in the nutrient solution in (a) a tomato-only cultivation area, (b) a tomato-basil mixed cultivation area, and (c) a tomato-chrysanthemum mixed cultivation area. In all treatment areas, each crop grew healthily. Furthermore, in all mixed cultivation areas, the density of contaminating bacteria in the nutrient solution was extremely low or below the detection limit, whereas in the control tomato-only cultivation area, the density of contaminating bacteria was high (Figure 59).

[0310] Figure 60 is a graph comparing (a) total fresh weight and (b) fruit yield of tomatoes in each treatment area. The vertical axis shows (a) total fresh weight (kg / plant) and (b) fruit yield (kg / m 2 ), the horizontal axis indicates the treatment area, the bars indicate the standard deviation, and different letters indicate significant differences at the 5% significance level (n=3). In the tomato / basil and tomato / chrysanthemum mixed plantings, each crop grew healthily, whereas the control tomato planting grew poorly. In the tomato / chrysanthemum mixed planting, there was no significant difference in fruit yield compared to the control (tomato alone), but growth was significantly promoted in total fresh weight. On the other hand, in the tomato / basil mixed planting, both fruit yield and total fresh weight were significantly higher than in the control (tomato alone) (Figure 60).

[0311] By adding a mixture of trace elements containing various plant extracts and cultivating them together with plants from the Asteraceae or Lamiaceae family, the density of contaminating bacteria in the nutrient solution was kept extremely low, and tomato fruit yields increased significantly (Figures 59 and 60). It is believed that the Fenton reaction between hydrogen peroxide exuded from the roots of basil (Lamiaceae) and chrysanthemum (Asteraceae) and the polyphenol-iron complex in the nutrient solution produces a powerful bactericidal effect. Therefore, it is believed that complete circulation hydroponic cultivation without replacing (discarding) the nutrient solution will be possible even in a simple greenhouse.

[0312] In addition, in the hydroponic cultivation of fruit vegetables, a solid medium such as rock wool is generally used to aid in the absorption of nutrients. However, in the cultivation method of this embodiment, the chelating action of various plant extracts helps the absorption of trace elements, so it is believed that high-quality fruit can be produced without using a solid medium.

[0313] (Test Example 9) Antibacterial test using plant extract trace element complex (2) The antibacterial activity of plant extract-trace element complexes, which are reaction products of various polyphenol-containing plant extracts and trace elements, against Escherichia coli was examined.

[0314] Plants containing polyphenols include the whole lily plant (30g), apple mint leaves and branches (10g), basil leaves and branches (20g), aromaticus leaves and branches (10g), loquat leaves and branches (10g), Houttuynia cordata whole plant (20g), eggplant leaves and branches (30g), hibiscus flowers (10g), tomato leaves and branches (20g), chili pepper leaves and branches (10g), and capsicum. Saba leaves and twigs (10g), Lady Plymouth Geranium leaves and twigs (10g), Mitsuba leaves and twigs (20g), Purple basil leaves and twigs (10g), Oregano leaves and twigs (10g), Coriander leaves and twigs (10g), Passion fruit leaves and twigs (40g), Pink pepper leaves and twigs (20g), Plum fruit (40g), Rhubarb leaves and twigs (20g), Arugula whole plant (20g), rose flowers (20g), pennyroyal mint whole plant (20g), cherry blossoms (40g), soybean leaves and twigs (20g), chive leaves and twigs (10g), horsetail leaves (30g), Akebia fruit (50g), thyme leaves and twigs (20g), goldenrod leaves and twigs (30g), perilla leaves and twigs (40g), goldenrod (sweet lily) The leaves and branches of (40 g), camphor tree leaves and branches (10 g), clove (Clove sieboldii) leaves and branches (10 g), bamboo leaves and branches (40 g), cinnamon leaves and branches (10 g), sweet vernal grass (Centella asiatica) leaves (50 g), lettuce leaves and stems (10 g), paprika leaves and branches (10 g), eucalyptus leaves and stems (10 g), and bell pepper leaves and branches (10 g) were used.

[0315] The polyphenol-containing plant matter of the above dry weight was placed in a 1000 mL beaker, 700 mL of distilled water was added, and the mixture was heated under pressure at 120°C for 20 minutes. The mixture was filtered through a paper filter to obtain a polyphenol-containing plant matter extract. Powdered trace element compounds (3 g of boric acid, 2 g of manganese(II) sulfate, 0.22 g of zinc sulfate, 0.05 g of copper sulfate, 0.01 g of sodium molybdate, and 15 g of iron(II) sulfate) were added to the extract, mixed, and reacted to obtain a reaction product (plant extract trace element complex solution). Antibacterial evaluation tests using the various plant extract trace element complex solutions obtained in this manner were performed in the same manner as in Test Example 4.

[0316] The results are shown in Figures 61 to 67. In Figure 61, (a) represents the control (no plant extract added), (b) represents the lily extract trace element complex, (c) represents the apple mint extract trace element complex, (d) represents the basil extract trace element complex, (e) represents the aromaticus extract trace element complex, and (f) represents the loquat extract trace element complex. In Figure 62, (g) represents the Houttuynia cordata extract trace element complex, (h) represents the eggplant extract trace element complex, (i) represents the hibiscus extract trace element complex, (k) represents the tomato extract trace element complex, (m) represents the chili pepper extract trace element complex, and (n) represents the cassava extract trace element complex. In Figure 63, (o) represents the Lady Plymouth Geranium extract trace nutrient complex, (p) represents the Mitsuba extract trace nutrient complex, (q) represents the Purple Basil extract trace nutrient complex, (r) represents the oregano extract trace nutrient complex, (s) represents the cilantro extract trace nutrient complex, and (t) represents the passion fruit extract trace nutrient complex. In Figure 64, (u) represents the pink pepper extract trace nutrient complex, (v) represents the plum extract trace nutrient complex, (w) represents the rhubarb extract trace nutrient complex, (x) represents the arugula extract trace nutrient complex, (y) represents the rose extract trace nutrient complex, and (z) represents the pennyroyal mint extract trace nutrient complex. In Figure 65, (a') represents the cherry blossom extract trace element complex, (b') represents the soybean extract trace element complex, (c') represents the chive leaf extract trace element complex, (d') represents the horsetail extract trace element complex, (e') represents the Akebia extract trace element complex, and (f') represents the thyme extract trace element complex. In Figure 66, (g') represents the solidago altissima extract trace element complex, (h') represents the perilla extract trace element complex, (i') represents the goldenrod extract trace element complex, (k') represents the camphor tree extract trace element complex, (m') represents the clove extract trace element complex, and (n') represents the bamboo grass extract trace element complex. In Figure 67, (o') indicates the cinnamon extract trace element complex area, (p') indicates the sweet vernal grass extract trace element complex area, (q') indicates the lettuce extract trace element complex area, (r') indicates the paprika extract trace element complex area, (s') indicates the eucalyptus extract trace element complex area, and (t') indicates the bell pepper extract trace element complex area.

[0317] Figures 61 to 67 show that all plant extract / trace nutrient complexes have antibacterial activity against E. coli. Therefore, it was found that by reacting various polyphenol-containing plant extracts with trace elements, plant extract / trace nutrient complexes with excellent antibacterial activity can be obtained. The above plant extracts contain unused agricultural residues, such as leaves and branches removed to attract plants (tomatoes, peppers, eggplants, etc.). Using these unused resources in the nutrient solution can significantly reduce the cost of hydroponic cultivation.

[0318] (Test Example 10) Antibacterial Comparative Test (2) The antibacterial activity of various polyphenol-containing plant extracts, trace elements, and their reaction products, plant extract-trace element complexes, against Escherichia coli was compared.

[0319] Preparation of plant extract and trace element complex solution: The polyphenol-containing plants used were fleabane flowers (10 g), whole chamomile plants (10 g), rhubarb leaves and branches (20 g), cassava leaves and branches (10 g), whole Houttuynia cordata plants (20 g), coriander leaves and branches (10 g), Swiss chard leaves and branches (20 g), tarana buds (tarana buds), leaves and branches (20 g), kudzu leaves and branches (10 g), and cinnamon leaves and branches (10 g).

[0320] The above-mentioned dry weights of various polyphenol-containing plants were placed in a 1000 mL beaker, 700 mL of distilled water was added, and the mixture was heated under pressure at 120°C for 20 minutes. Powdered trace element compounds (3 g of boric acid, 2 g of manganese(II) sulfate, 0.22 g of zinc sulfate, 0.05 g of copper sulfate, 0.01 g of sodium molybdate, and 15 g of iron(II) sulfate) were added and mixed. Distilled water was added to this mixture to make a 1000 mL solution, which was used as a plant extract trace element complex solution.

[0321] Preparation of plant extracts: The above-mentioned dry weights of various polyphenol-containing plants were placed in a 1000 mL beaker, 700 mL of distilled water was added, and the mixture was heated under pressure at 120°C for 20 minutes. Distilled water was then added to the mixture to make a 1000 mL volume, which was used as a plant extract.

[0322] Preparation of trace element mixture: In a 1000 mL beaker, 700 mL of distilled water and powdered trace element compounds (boric acid 3 g, manganese (II) sulfate 2 g, zinc sulfate 0.22 g, copper sulfate 0.05 g, sodium molybdate 0.01 g, iron (II) sulfate 15 g) were added and mixed. Distilled water was added to this to make a 1000 mL solution, which was used as a trace element mixture.

[0323] Antibacterial evaluation tests were carried out in the same manner as in Test Example 4 using the various plant extract trace element complex solutions, plant extracts, or trace element mixture solutions obtained in this manner.

[0324] The results are shown in Figures 68 to 72. Figure 68 shows the plant extracts, trace elements, and their reaction products (plant extract trace element complex) from (a) fleabane and (b) chamomile. Figure 69 shows the plant extracts, trace elements, and their reaction products (plant extract trace element complex) from (a) rhubarb and (b) cassava. Figure 70 shows the plant extracts, trace elements, and their reaction products (plant extract trace element complex) from (a) houttuynia cordata and (b) coriander. Figure 71 shows the plant extracts, trace elements, and their reaction products (plant extract trace element complex) from (a) Swiss chard and (b) taros. Figure 72 shows the plant extracts, trace elements, and their reaction products (plant extract trace element complex) from (a) kudzu and (b) cinnamon.

[0325] The formation of an inhibitory halo was confirmed in all treatments, but a larger inhibitory halo was formed with the plant extract-trace element complex solution than with trace elements alone or plant extract alone (Figures 68 to 72). These results show that combining plant extract and trace elements exerts a stronger antibacterial effect than using either alone. This is thought to be due to the synergistic effect of the components contained in the plant extract and the trace elements.

[0326] (Test Example 11) Antibacterial test using mushroom extract trace element complex The antibacterial activity of a mushroom extract trace element complex prepared using mushrooms instead of polyphenol-containing plants was examined against Escherichia coli.

[0327] Grifola frondosa and Lentinula edodes (whole) were used as mushrooms. 10 g of these mushrooms were placed in a 1000 mL beaker, 700 mL of distilled water was added, and the mixture was heated at 120°C under pressure for 20 minutes. The supernatant was filtered through filter paper to obtain a mushroom extract. Powdered trace element compounds (3 g of boric acid, 2 g of manganese(II) sulfate, 0.22 g of zinc sulfate, 0.05 g of copper sulfate, 0.01 g of sodium molybdate, and 15 g of iron(II) sulfate) were added to the extract, mixed, and reacted to obtain a reaction product (mushroom extract trace element complex solution). An antibacterial evaluation test using the mushroom extract trace element complex solution thus obtained was performed in the same manner as in Test Example 4.

[0328] The results are shown in Figure 73. In Figure 73, (a) shows the control group (no mushroom extract added), (b) shows the Maitake extract trace element complex group, and (c) shows the Shiitake extract trace element complex group. All of the mushroom extract trace element complexes exhibited high antibacterial properties (Figure 73). This demonstrates that even when using mushroom extract instead of polyphenol-containing plant matter, it is possible to produce trace element complexes with excellent antibacterial properties. Therefore, it is expected that these mushroom extract trace element complexes can be added to culture solutions for hydroponic cultivation.

[0329] The above has described in detail the embodiments and examples of the present disclosure with reference to the drawings, but the specific configurations are not limited to these, and design changes that do not deviate from the gist of the present disclosure are included in the present disclosure.

[0330] For example, although the above examples describe hydroponic cultivation methods using extracts from various plants or mushrooms, the present disclosure is not limited thereto. Specifically, polyphenols such as compounds including catechin, tannic acid, tannin, chlorogenic acid, caffeic acid, neochlorogenic acid, cyanidin, proanthocyanidin, thearubigin, rutin, flavonoids, flavones, chalcones, xanthophyll, carnosic acid, eriocitrin, nobiletin, tangeretin, magnolol, honokiol, ellagic acid, lignans, curcumin, coumarin, catechol, procyanidins, theaflavin, rosmarinic acid, xanthone, quercetin, resveratrol, gallic acid, and phlorotannins, as well as compositions thereof, and compounds contained in plants or mushrooms, such as alkaloids, phytosterols, triterpenoids, organic acids, and sugars, as well as compositions thereof, can also be used as the polyphenol-containing plant or mushroom extract of the present disclosure. [Explanation of symbols]

[0331] 1 Hydroponic cultivation system 2,21,22 Piping P, P1, P2, P3, P4, P5 pumps 31, 32, 33, 34 CROSS-REFERENCE TO VALVE-RELATED APPLICATIONS

[0332] This application claims priority based on Patent Application No. 2021-065601, filed with the Japan Patent Office on April 8, 2021, the entire disclosure of which is incorporated herein by reference in its entirety.

Claims

1. A method for producing a mushroom extract-trace nutrient mixture, comprising: mixing a mushroom extract and trace nutrient in the presence of water; Adding the mushroom extract trace element mixture to a culture solution; and performing hydroponic cultivation using the culture solution, The hydroponic cultivation method, wherein the mushroom extract and trace element mixture contains a complex of the mushroom extract and the trace element.

2. 2. The hydroponic cultivation method according to claim 1, wherein the trace elements contain iron and one or more elements selected from the group consisting of boron, manganese, zinc, copper and molybdenum.

3. 3. The hydroponic cultivation method according to claim 1 or 2, wherein the mushrooms are one or more parts of mycelium, fruiting bodies, and waste mushroom beds of one or more mushrooms selected from the group consisting of Maitake mushroom, Shiitake mushroom, Enokitake mushroom, Bunashimeji mushroom, Honshimeji mushroom, Nameko mushroom, Pleurotus ostreatus, mushroom, Matsutake mushroom, and Pleurotus eryngii.

4. The hydroponic cultivation method according to any one of claims 1 to 3, wherein only Asteraceae or Lamiaceae plants are cultivated, or Asteraceae or Lamiaceae plants are cultivated together with other plants, or Asteraceae plants and Lamiaceae plants are cultivated together.

5. In the mixed planting, 5. The hydroponic cultivation method according to claim 4, wherein two or more kinds of plants are cultivated in different hydroponic cultivation zones, and the nutrient solution is circulated between these hydroponic cultivation zones.

6. In the mixed planting, 5. The hydroponic cultivation method according to claim 4, wherein two or more types of plants are cultivated in the same hydroponic cultivation area.

7. The "Asteraceae plant" is one or more plants selected from chrysanthemum, aster, sunflower, calendula, garland chrysanthemum, marigold, cosmos, peonies, dahlia, zinnia, margaret, dimorphotheca, cornflower, blue thistle, burdock, safflower, artichoke, lettuce, and salad greens; The "Lamiaceae plant" is one or more plants selected from the group consisting of perilla, perilla, basil, mint, hyssop, rosemary, lavender, sage, marjoram, oregano, thyme, lemon balm, salvia, barkberry, ajuga, Chinese artichoke, and horsetail. The hydroponic cultivation method according to any one of claims 4 to 6.

8. A hydroponic cultivation method according to any one of claims 1 to 7, which is a complete circulation method in which the culture solution is not replaced.

9. It is a complete circulation type in which the culture medium is not replaced, The pH of the culture medium is not adjusted, and The hydroponic cultivation method according to any one of claims 1 to 7, wherein no solid medium is used.

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