A solid medium for soilless culture prepared by fermenting coffee grounds with a mixed culture

Abstract

The application provides a solid substrate for soilless culture prepared by fermentation of coffee residue and mixed bacteria, wherein the mixed bacteria include yeast, bacillus subtilis and trichoderma viride; the weight ratio of the yeast, the bacillus subtilis and the trichoderma viride is 2:1:3. The solid substrate for soilless culture is rich in trace elements required by plant growth, has low bulk density, high water holding porosity, and is controllable. The solid substrate for soilless culture can effectively improve the plant growth environment, has disease resistance and insect resistance, and improves the survival rate of plants.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of coffee residue utilization, in particular to a solid substrate for soilless culture prepared by fermentation of mixed strains of coffee residue. BACKGROUND

[0002] Coffee residue generally refers to the powder or broken residue left after coffee extraction, which has bitter and sour taste and no nutritional value. Therefore, at present, coffee residue is mostly buried as waste. After being buried, coffee residue produces a large amount of methane, which will exacerbate the greenhouse effect, increase the total amount of carbon emissions, and harm the environment, and does not meet the green environmental protection requirements.

[0003] In order to improve the added value of coffee residue, it is necessary to recycle coffee residue. The composition of coffee residue is complex, including polysaccharides, polyphenols and other compounds. In order to increase its added value, modification of coffee residue and extraction of active substances and other treatment methods are used. These methods still produce a certain amount of waste during the process, and this part of waste is difficult to utilize again. Therefore, it is of great significance to provide a treatment method that can utilize coffee residue as a whole. SUMMARY

[0004] In view of this, the present application provides a solid substrate for soilless culture prepared by fermentation of mixed strains of coffee residue, which is obtained after fermentation of coffee residue and mixed strains. The solid substrate for soilless culture is rich in trace elements required for plant growth, has low bulk density, has high water holding porosity, and the soilless culture substrate has strong controllability, can effectively improve the plant growth environment, has disease resistance and insect resistance, and improves the plant survival rate.

[0005] The technical scheme of the present application is as follows:

[0006] A solid substrate for soilless culture prepared by fermentation of mixed strains of coffee residue, which is obtained after fermentation of coffee residue and mixed strains. The mixed strains include yeast, Bacillus subtilis and Trichoderma viride. The weight ratio of yeast, Bacillus subtilis and Trichoderma viride is 2:1:3.

[0007] The solid substrate for soilless culture is rich in trace elements, has high available phosphorus and potassium content, low electrical conductivity, low pH value, low bulk density and high water holding porosity, and the total porosity is in the range of 50%-60%, which can effectively balance water and ventilation. It has insect resistance. The bulk density, porosity, pH value, electrical conductivity and water holding capacity at this level meet the requirements of plant growth.

[0008] The soilless cultivation solid substrate obtained after fermentation of the application is rich in various trace elements, provides essential nutrients for soil, and has an important influence on the growth and quality of plants; after fermentation, the content of phosphorus and potassium in the solid substrate is high, and the effective phosphorus and available potassium represent the content of phosphorus and potassium in soil that can be absorbed and utilized by plants, so the solid substrate is beneficial to promoting the growth and flowering of plants; in addition, during the fermentation process, the electrical conductivity of the raw material decreases significantly, and the pH value decreases, so that the salt content in the solid substrate is low and the pH value is suitable for plant growth; and the solid substrate has low bulk density, which is helpful for root expansion and gas exchange, provides sufficient oxygen for plants, and exhibits excellent water holding capacity, can effectively maintain water, and has appropriate total porosity, which can balance water and aeration; the coffee grounds mixed strain fermented solid substrate of the application has the advantages of easy material selection, low cost, improved plant growth environment, improved plant survival rate, insect resistance and the like.

[0009] Preferably, before fermentation, the carbon-nitrogen ratio of the coffee grounds is adjusted to 20-30:1, and the moisture content is ≥55%.

[0010] Preferably, the addition amount of the mixed bacteria in the coffee grounds substrate is 1‰-2‰.

[0011] Preferably, before fermentation, the pH of the coffee grounds substrate is 6-8, and the fermentation time is 50-80 days.

[0012] Preferably, the fermentation process is aerobic fermentation, the environmental temperature during fermentation is 15-30℃, and the pile is turned over and aerated on time every day.

[0013] Preferably, in the mixed bacteria, the effective viable count of the yeast is ≥1 billion / g; the effective viable count of the Bacillus subtilis is ≥5 billion / g; and the effective viable count of the Trichoderma viride is ≥15 billion / g.

[0014] Compared with the prior art, the application has the following beneficial effects:

[0015] 1. In the application, coffee grounds are mixed with composite bacteria and then fermented to prepare coffee grounds solid substrate, which is used as a soilless cultivation solid substrate material to replace soil; during the fermentation process, the electrical conductivity and pH of the coffee grounds decrease significantly, so that the obtained solid substrate is suitable for plant growth; in addition, the solid substrate obtained by fermentation is rich in trace elements such as sulfur (S), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), arsenic (As) and silicon (Si), which provides trace elements for plant growth; the total porosity and water holding capacity of the solid substrate form an environment conducive to plant growth.

[0016] 2. The soilless cultivation solid substrate of the present invention uses coffee grounds which are easy to obtain and low in cost. After fermentation by mixed bacteria, a solid substrate with total porosity and water holding capacity that meet the needs of plant growth is obtained. When this solid substrate is applied in soilless cultivation of plants, it can effectively improve the plant growth environment and make the plants grow vigorously.

[0017] 3. The soilless culture solid substrate prepared by fermentation of coffee grounds with mixed microbial strains in this invention uses coffee grounds, a waste product, as raw material. Through microbial fermentation, it not only solves the problem of coffee grounds disposal, but also prepares a soilless culture solid substrate rich in trace elements and nutrients. It can effectively repel pests, improve plant disease resistance, and promote plant growth and flowering, thus having good environmental and economic benefits.

[0018] 4. The solid substrate for soilless cultivation of coffee grounds provided by this invention is rich in trace elements: sulfur (S), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), arsenic (As) and silicon (Si); and the substrate has a bulk density of 32.04%, a total porosity of 53.65%, a water holding capacity of 212.68%, and an aeration porosity of 17.59%. Attached Figure Description

[0019] Figure 1 This is a photo of coffee grounds before fermentation in Example 1.

[0020] Figure 2 Fermentation photos were prepared for Example 1.

[0021] Figure 3 This is a photograph of the substrate during fermentation in Example 1.

[0022] Figure 4 This is a photograph of temperature detection during fermentation in Example 1.

[0023] Figure 5 This is a photograph of the soilless culture solid substrate obtained after fermentation in Example 1.

[0024] Figure 6 This is a temperature change curve during the fermentation process of Example 1.

[0025] Figure 7 Photographs showing conductivity measurements.

[0026] Figure 8 This is a bar chart showing the effect of different proportions of soilless cultivation solid substrate added on cucumber growth in Experiment 1.

[0027] Figure 9 This is a bar chart comparing the properties of solid substrate and soil in soilless cultivation in Experiment 3.

[0028] Figure 10Column chart for comparison of the content of available phosphorus and available potassium in soil and solid substrate for soilless culture in Experiment 3. DETAILED DESCRIPTION

[0029] In order to enable persons skilled in the art to better understand the technical solutions in the present application, the technical solutions of the present application will be clearly and completely described below in combination with the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by persons skilled in the art without creative work should fall within the protection scope of the present application.

[0030] Embodiment 1

[0031] In combination Figures 1-5 A solid substrate for soilless culture prepared by fermentation of coffee grounds and mixed bacteria, obtained after fermentation of coffee grounds and mixed bacteria;

[0032] The specific process is as follows:

[0033] (1) 17.6 kg of coffee grounds were added to a fermentation barrel, the carbon-nitrogen ratio of the coffee grounds was adjusted to 25:1, then water was added to make the moisture content of the coffee grounds 61.38%, and the pH was controlled to 7.0;

[0034] (2) 17.6 g of mixed bacteria were added to the coffee grounds obtained in step (1) and mixed evenly; the fermentation barrel was placed in a place with sunlight and warmth, the room temperature was 25℃, a thermometer was inserted, the fermentation temperature was 65±1℃, the temperature was measured every 24 hours, and the fermentation was carried out for 75 days;

[0035] In the mixed bacteria, the weight ratio of Saccharomyces cerevisiae, Bacillus subtilis and Trichoderma viride was 2:1:3; the effective viable count of Saccharomyces cerevisiae was 1 billion / g; the effective viable count of Bacillus subtilis was 500 million / g; and the effective viable count of Trichoderma viride was 1.5 billion / g;

[0036] During the fermentation process, the temperature of the heap gradually increased from the initial 30℃ to 50℃, then increased to 61℃, artificial heating was used to make the heap reach 70℃, and then the temperature gradually decreased to 40℃, obtaining the solid substrate for soilless culture, and the fermentation temperature change curve is shown in Figure 6 The taste of the solid substrate for soilless culture changed from the original coffee grounds fragrance to sour and rotten smell, the color changed from brown to light black, it was loose and had no peculiar smell, and it was rich in various trace elements, suitable for plant growth.

[0037] Embodiment 2

[0038] A solid substrate for soilless culture prepared by fermentation of coffee grounds and mixed bacteria, obtained after fermentation of coffee grounds and mixed bacteria;

[0039] The specific process is as follows:

[0040] (1) 17.6 kg of coffee grounds were added to a fermentation barrel, the carbon-nitrogen ratio of the coffee grounds was adjusted to 20:1, then clean water was added to make the moisture content of the coffee grounds 57.61%, and the pH was controlled to be 6.0;

[0041] (2) 26.4 g of mixed bacteria were added to the coffee grounds obtained in step (1) and mixed evenly; the fermentation barrel was placed in a place with sunlight and warmth, the room temperature was 20℃, a thermometer was inserted, the temperature was measured every 24 hours, and the fermentation was carried out for 65 days;

[0042] In the mixed bacteria, the weight ratio of Saccharomyces, Bacillus subtilis and Trichoderma viride was 2:1:3; the effective viable count of Saccharomyces was 1 billion / g; the effective viable count of Bacillus subtilis was 500 million / g; and the effective viable count of Trichoderma viride was 1.5 billion / g;

[0043] During the fermentation process, the temperature of the heap gradually increased from the initial 30℃ to 54℃, then increased to 65℃, the heap was artificially heated to 72℃, then naturally cooled down, and the temperature gradually decreased to 40℃, thereby obtaining a soilless cultivation solid substrate; the fermentation time was shortened by 10 days compared with Example 1; the taste of the soilless cultivation solid substrate changed from the initial coffee grounds fragrance to a sour and rotten smell, the color changed from brown to light black, it was loose and had no peculiar smell, and it was rich in various trace elements and suitable for plant growth.

[0044] Example 3

[0045] A soilless cultivation solid substrate prepared by fermenting coffee grounds and mixed bacteria;

[0046] The specific process is as follows:

[0047] (1) 17.6 kg of coffee grounds were added to a fermentation barrel, the carbon-nitrogen ratio of the coffee grounds was adjusted to 30:1, then clean water was added to make the moisture content of the coffee grounds 63.41%, and the pH was controlled to be 8.0;

[0048] (2) 35.2 g of mixed bacteria were added to the coffee grounds obtained in step (1) and mixed evenly; the fermentation barrel was placed in a place with sunlight and warmth, the room temperature was 15℃, a thermometer was inserted, the temperature was measured every 24 hours, and the fermentation was carried out for 80 days;

[0049] In the mixed bacteria, the weight ratio of Saccharomyces, Bacillus subtilis and Trichoderma viride was 2:1:3; the effective viable count of Saccharomyces was 1 billion / g; the effective viable count of Bacillus subtilis was 500 million / g; and the effective viable count of Trichoderma viride was 1.5 billion / g;

[0050] During the fermentation, the temperature of the pile gradually increases from the initial 30℃ to 55℃, and then increases to 61℃, the pile is heated to 70℃ by artificial heating, and then naturally cools down, and the temperature gradually decreases to 40℃, to obtain the soilless cultivation solid substrate, and the fermentation time is increased by 5 days compared with example 2; the taste of the soilless cultivation solid substrate changes from the initial coffee residue fragrance to sour smell, the color changes from brown to light black, it is loose and has no peculiar smell, and is rich in various trace elements, and is suitable for plant growth.

[0051] The coffee residue soilless cultivation solid substrate prepared according to example 1 is subjected to conductivity determination (see Figure 7 ), trace element determination, acid-base determination, porosity determination, bulk density determination, effective phosphorus determination, and rapid potassium determination. The experimental results are shown in Tables 1 and 2.

[0052] The experimental standards and experimental methods used in the present application are as follows:

[0053] Determination of soil available phosphorus (sodium bicarbonate extraction-molybdenum antimony anti-colorimetric method);

[0054] Determination of soil available potassium (ammonium acetate extraction-flame photometry);

[0055] Acid-base determination: hydrogen ion concentration index (pH value), the soilless cultivation solid substrate is soaked, filtered and placed with distilled water, and then the pH value is determined using an acidity meter;

[0056] Porosity determination: the ratio of the volume of the pores in the solid substrate test block to the total volume of the test block is measured;

[0057] Bulk density determination: saturated gravity drainage method is used;

[0058] Trace element determination: inductively coupled plasma mass spectrometry

[0059] Table 1 Comparison of soilless cultivation solid substrate before and after fermentation

[0060]

[0061] Before fermentation, 5 coffee residue samples are taken for pH and conductivity detection, and after fermentation, 5 soilless cultivation solid substrate samples of example 1 are taken for pH and conductivity detection, and the results are shown in Table 1; according to the detection results in Table 1, after fermentation, the conductivity of the coffee residue is greatly reduced, the pH value is reduced, and the salt content is reduced, which is more suitable for plant growth.

[0062] Table 2 Determination results of the soilless cultivation solid substrate of example 1

[0063]

[0064] Note: Air porosity = total porosity - water content x bulk density; total porosity = (1 - bulk density / specific gravity) x 100%.

[0065] In combination with Table 2, it can be seen that the soilless culture solid substrate prepared by using the application has the advantages of low bulk density, high water holding capacity, appropriate total porosity, rich in various trace elements, and high content of available phosphorus and available potassium; wherein, the average value of available phosphorus is 641.8 mg / kg, and the average value of available potassium is 1009.8 mg / kg; this shows that the content of phosphorus and potassium is higher after fermentation of coffee grounds, which is beneficial to promoting the growth and flowering of plants;

[0066] In the application, by controlling the carbon-nitrogen ratio and water content of the coffee grounds, and controlling the mass ratio of the coffee grounds and the mixed bacteria, the pH, bulk density, water holding capacity, total porosity and air porosity of the obtained soilless culture solid substrate create a good environment for plant growth, wherein, the low bulk density is helpful for root expansion and gas exchange; the high water holding porosity shows excellent water holding capacity and can effectively maintain water; the total porosity can balance water and ventilation; therefore, after fermentation, the obtained solid substrate can provide a good growth environment for plant growth and seed growth;

[0067] In addition, after fermentation, the electrical conductivity of the soilless culture solid substrate is reduced, which is in the range of 2.68-2.8, under the premise that the solid substrate is rich in trace elements such as sulfur, manganese, iron, copper, zinc, arsenic and silicon, low electrical conductivity can increase the solubility of trace elements, promote the absorption of trace elements by plants, and further promote the growth of plants; and after fermentation, the content of available phosphorus and available potassium in the solid substrate is increased, which further promotes the growth of plants.

[0068] Experiment 1: Effect of different proportions of soilless culture solid substrate addition amount on cucumber growth and flowering period

[0069] The experiment lasted for 3 months, the soilless culture solid substrate prepared in Example 1 and soil were mixed according to a dry weight ratio of 0:100, 10:90, 15:85, 20:80, 25:75 and 100:0, and each group was treated and mixed, 1 kg of mixed sample was loaded into each pot, 3 pots were loaded for each group of treatment for cucumber planting, and no fertilizer was applied during the test period. Each pot was planted with 1 plant, and after planting, the soil was irrigated, and then the irrigation interval was adjusted according to the weather and soil water content.

[0070] From the day of cucumber planting, the plant height was taken as the determination index during the growth period, and the soft ruler was used for measurement. The plant height of 3 plants was measured every 1 week from the day of planting to the flowering period, and the average value of the plant height of 3 plants was taken as the experimental data of this week and recorded. The size of the cucumber corolla and the number of flowers were recorded, and the recording period was 4 weeks, and the results are shown in Table 1. Figure 8 ;

[0071] Figure 8The experimental results show that the soilless cultivation solid substrate addition amount of example 1 is positively correlated with the height of cucumber, compared with the soil group (CK), the number of cucumber corolla and flowers of the group adding the soilless cultivation solid substrate is increased in different degrees, the more the soilless cultivation solid substrate addition amount is, the better the effect is; this is because the effective phosphorus and available potassium content in the soilless cultivation solid substrate provided by the application is increased, the phosphorus fertilizer promotes flowering and fruiting, and the potassium fertilizer can improve the disease resistance of plants.

[0072] Experiment two: verification of the insect repellent property of the coffee residue substrate

[0073] Snails and ants are used as representative insects to verify the insect repellent property of the soilless cultivation solid substrate, the experimental container is a disposable polyethylene meal box, the meal box is equally divided into three parts along the longitudinal direction, fresh soil with a thickness of about 2mm is scattered on the control side, the middle part is blank, and the experimental side is scattered with the same thickness of different proportions of soil-soilless cultivation solid substrate mixture and grass charcoal, and the water content of the two sides is adjusted to be the same.

[0074] The soilless cultivation solid substrate is verified for the insect repellent property, the experimental side is respectively the soilless cultivation solid substrate of example 1 + soil and grass charcoal + soil. 10 insects are randomly placed in the middle blank area, and are placed in a dark room for culture and observation, and each group is repeated for not less than 5 times. The experiment lasts for 6 hours, and the insect distribution position is measured and counted every 2 hours. The average value of each group of repeated treatments at the same time is taken as the final data, and the experimental results are shown in table 3.

[0075] Table 3: results of the insect repellent experiment of the coffee residue substrate

[0076]

[0077] It can be seen from the results in table 3 that, compared with grass charcoal, the soilless cultivation solid substrate has a certain insect resistance; that is, the soilless cultivation solid substrate prepared by the application has insect resistance, can drive or inhibit some insects and fungi harmful to plants, such as aphids, ants, snails, slugs and other pests, and can protect the health and appearance of plants; also has antibacterial property, such as the acidity can inhibit the growth of botrytis cinerea, anthracnose and other fungi, and the nitrogen content of the solid substrate can increase the disease resistance of plants.

[0078] In the application, the coffee residue, a waste, is used as a raw material, and is treated by fermentation of strains, which not only solves the problem of coffee residue treatment, but also prepares a soilless cultivation solid substrate rich in trace elements and nutrients. The soilless cultivation solid substrate rich in trace elements is beneficial to promoting the growth and flowering of plants, can drive pests, improve the disease resistance of plants, and has the advantages of ensuring the porosity and strength of the soilless cultivation solid substrate and improving the survival rate of plants.

[0079] Experiment three: comparison of the properties of the soilless cultivation solid substrate and soil

[0080] The performance of the soilless cultivation solid substrate and soil in Example 1 was tested separately, and the results were obtained. Figure 9 and Figure 10 The data shown. Combined with... Figures 9-10 It can be seen that coffee grounds have a strong water-holding capacity compared to soil, which can retain water and fertilizer; the content of available phosphorus and available potassium is higher than that of soil, which can promote flowering and fruiting of plants and improve plant disease resistance.

[0081] Although the present invention has been described in detail with reference to preferred embodiments, it is not limited thereto. Various equivalent modifications or substitutions can be made to the embodiments of the present invention by those skilled in the art without departing from the spirit and essence of the invention, and such modifications or substitutions should all be within the scope of the present invention. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should also be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the scope of the claims.

Claims

1. A solid substrate for soilless culture produced by fermentation of coffee grounds mixed with a bacterial species, characterized in that, The coffee grounds and mixed bacteria are fermented to obtain; wherein the mixed bacteria include yeast, bacillus subtilis and trichoderma viride; the weight ratio of the yeast, bacillus subtilis and trichoderma viride is 2:1:3; Before fermentation, the carbon-nitrogen ratio of the coffee grounds is adjusted to 20-30:1, and the water content is ≥55%; The fermentation process is aerobic fermentation, the environmental temperature during fermentation is 15-30℃, and the pile is turned over and aerated every 24 hours; In the mixed bacteria, the effective viable count of the yeast is ≥10 billion / g; the effective viable count of the bacillus subtilis is ≥5 billion / g; and the effective viable count of the trichoderma viride is ≥15 billion / g.

2. The soilless culture solid medium prepared by fermenting the coffee grounds mixed bacteria species according to claim 1, characterized in that, The weight ratio of the coffee grounds to the mixed bacteria is 1‰-2‰.

3. The solid substrate for soilless culture prepared by fermentation of coffee grounds mixed bacteria species according to claim 1, characterized in that, Before fermentation, the pH of the coffee grounds substrate is 6-8, and the fermentation time is 50-80 days.

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