Spirulina nutritional agent and use method thereof

Abstract

The invention discloses a spirulina nutritional agent and a use method thereof, the spirulina nutritional agent comprises a basic nutritional agent and a brown algae extract, and the basic nutritional agent comprises a carbon source, a nitrogen source, a phosphorus source, a potassium source, a magnesium source, a calcium source, a sulfur source and trace elements. The invention relates to the technical field of agricultural fertilizers, adopts brown algae extract as an additive, is high in absorption and utilization rate, and has the capabilities of promoting the growth and reproduction of spirulina, improving the yield of spirulina and resisting high-temperature stress. The spirulina nutritional agent provided by the invention is simple in use method, can realize family culture of spirulina, and has great popularization and application prospects.

Description

Technical Field

[0001] The invention relates to the technical field of agricultural fertilizers, and more particularly to a spirulina nutrient and a use method thereof. Background Art

[0002] With the development of urbanization in China, people's lifestyles have changed a lot. The fast-paced lifestyle is accompanied by food safety issues and the lack of exercise among the people, which eventually leads to an increasing number of sub-healthy people, especially the three highs of the middle-aged and elderly people have become a common phenomenon. The probability of cancer and cardiovascular and cerebrovascular diseases has increased significantly, and there is a trend of developing towards younger people, which has attracted people's great attention. Spirulina has a protein content of up to 60%-70%, and is easily digested and absorbed by the human body. It is a high-quality green edible protein source. More importantly, Spirulina contains rich physiologically active ingredients, such as β-carotene, chlorophyll, α, γ-linolenic acid, polysaccharides, phycocyanin, vitamins, glycolipids, trace elements, etc., which have important medical and health care value. It can regulate human physiological functions, promote cell metabolism, enhance the body's immunity, anti-aging, anti-oxidation, anti-radiation, and has significant effects on tumors, hypertension, heart disease, diabetes, liver disease, stomach disease, pancreatitis, anemia, obesity, heavy metal poisoning, etc. It can also relieve malnutrition, facilitate trauma treatment and scar healing, and promote hematopoietic function. It is praised by the Food and Agriculture Organization of the United Nations (FAO) as "the most ideal food for mankind's future."

[0003] Spirulina research and cultivation has been developed in my country for more than 50 years, and is now mainly used in the feed industry and health care products. Spirulina used for health care at home and abroad mainly exists in the form of tablets or capsules, which need to be processed by high temperature during the production process, resulting in the loss of most of the active substances and nutrients in Spirulina, greatly reducing its efficacy.

[0004] The growth of spirulina is affected by various factors such as temperature, light, pH, salt, dissolved oxygen, etc. The optimum growth temperature of spirulina is 20-35°C, the lower limit of growth is 16°C, and the upper limit of growth is 42°C; the optimum pH is 8.0-10.5. If the pH is too low, it is easily contaminated by other algae, and if it is too high, the available CO2 is limited; the optimum light intensity is 25-30klx. In the process of spirulina cultivation, due to the influence of environmental factors, the algae filaments are prone to shortening, abnormal yellow-green color, aging and lysis, cell contents seepage, and the culture medium turns yellow, which not only reduces the yield of spirulina but also affects its taste. In addition, the protein content of spirulina is high and it is very easy to corrupt. Therefore, fresh spirulina has been difficult to be quickly promoted in the market. The Chinese invention patent with publication number CN200910114593 discloses a method for family cultivation of saltwater spirulina. The method adds trace nutrients such as cobalt nitrate and titanium sulfate, and the formula reacts to produce precipitation. It needs to be left to stand and the supernatant is taken for use, and the preparation is relatively complicated. A Chinese invention patent with publication number CN102533557B discloses a culture medium for overwintering rejuvenation and seed preservation of Spirulina. The culture medium uses oligosaccharides and vitamins as additives. Although it can improve the cold resistance of Spirulina, the culture medium also has the problem that mineral nutrients easily react with phosphorus sources to generate precipitation, thereby reducing the absorption and utilization of nutrients by Spirulina. Summary of the invention

[0005] In view of the above technical problems, the present invention provides a spirulina nutrient, comprising a basic nutrient and a brown algae extract, wherein the basic nutrient comprises a carbon source, a nitrogen source, a phosphorus source, a potassium source, a magnesium source, a calcium source, a sulfur source and trace elements.

[0006] Carbon source, nitrogen source, phosphorus source, potassium source, magnesium source, calcium source, sulfur source and trace elements can ensure the nutrient supply during the growth of Spirulina. Brown algae extract can not only increase the yield of Spirulina, but also improve Spirulina's resistance to high temperature and protect the integrity of Spirulina cell wall.

[0007] Preferably, the basic nutrient agent includes the following nutrient elements in parts by weight: 7-11 parts of sodium nitrate, 2-6 parts of potassium dihydrogen phosphate, 7-17 parts of potassium sulfate, 9-16 parts of sodium chloride, 0.7-1.3 parts of EDTA-Ca, 0.1-0.5 parts of EDTA-Fe, 0.1-0.5 parts of EDTA-Zn, 0.02-0.04 parts of EDTA-Mn, 0.001-0.002 parts of EDTA-Cu, 2-5 parts of EDTA-Mg, 0.01-0.05 parts of boric acid, 0.0006-0.001 parts of ammonium heptamolybdate, 0.6-2.5 parts of urea, and 98-238 parts of sodium bicarbonate.

[0008] Sodium bicarbonate is used as the carbon source of the nutrient; urea is used as both the carbon source and the nitrogen source, sodium nitrate is used as the nitrogen source and the sodium source, potassium dihydrogen phosphate is used as both the phosphorus source and the potassium source, and potassium sulfate is used as the potassium source and the sulfur source; EDTA-Mg and EDTA-Ca are used as the magnesium source and the calcium source of the nutrient; EDTA-Fe, EDTA-Mn, EDTA-Cu, EDTA-Zn, boric acid, and ammonium heptamolybdate are used as the trace element source of the nutrient. Carbon, nitrogen, phosphorus, and potassium are macronutrients required by plants, magnesium, calcium, and sulfur are medium-nutrients required by plants, and the types of trace nutrients can be flexibly selected according to the needs of plant growth and development. The above nutrients are essential for the normal growth and development of plants.

[0009] Using EDTA-chelated magnesium, calcium, iron, manganese, copper and zinc as raw materials can prevent the reaction of phosphate with these mineral nutrients, making the Spirulina culture solution clear and free of precipitation, thereby improving the effectiveness of mineral nutrients and avoiding the impact of precipitation on the growth of Spirulina.

[0010] Preferably, the basic nutrient agent includes the following nutrient elements in parts by weight: 9.80 parts of sodium nitrate, 3.61 parts of potassium dihydrogen phosphate, 9.05 parts of potassium sulfate, 11.45 parts of sodium chloride, 0.90 parts of EDTA-Ca, 0.34 parts of EDTA-Fe, 0.34 parts of EDTA-Zn, 0.033 parts of EDTA-Mn, 0.0016 parts of EDTA-Cu, 3.27 parts of EDTA-Mg, 0.025 parts of boric acid, 0.0008 parts of ammonium heptamolybdate, 2.5 parts of urea, and 168 parts of sodium bicarbonate.

[0011] The above-mentioned nutritional elements in parts by weight can balance various nutritional elements required in the growth process of Spirulina, which is beneficial to improving the resistance of Spirulina to adverse conditions and promoting the good growth of Spirulina.

[0012] Preferably, the preparation method of the brown algae extract is:

[0013] S1: preparing brown algae slurry and adjusting pH and temperature, adding cellulase and xylanase for primary enzymatic hydrolysis;

[0014] S2: adjusting the pH and temperature of the solution after the primary enzymatic hydrolysis, and adding papain for secondary enzymatic hydrolysis;

[0015] S3: adjusting the pH and temperature of the solution after the secondary enzymatic hydrolysis, and adding pectinase for tertiary enzymatic hydrolysis;

[0016] S4: taking the solution after the third-stage enzymatic hydrolysis and concentrating it by centrifugation to make the concentration of the concentrate greater than or equal to 1.05 g / ml, thereby obtaining a brown algae extract.

[0017] The brown algae extract after three-stage enzymatic hydrolysis contains a large amount of active substances such as brown algae oligosaccharides and brown algae polyphenols, which can promote crop growth and improve crop resistance.

[0018] Preferably, the pH adjusting agent in step S1, step S2, step S3 and step S4 is an inorganic acid and / or an inorganic base with a concentration less than 3 wt %.

[0019] Inorganic acid and / or inorganic base as pH adjusting agents can prevent the sudden termination of the enzymatic reaction, effectively prevent the denaturation of the protease, and ensure the accuracy of the extraction results.

[0020] Preferably, the inorganic acid is hydrochloric acid, and the inorganic base is sodium hydroxide.

[0021] Hydrochloric acid and sodium hydroxide are cost-effective as pH adjusters and have high sensitivity in adjusting reactions.

[0022] Preferably, the enzyme activities of the cellulase and xylanase are greater than or equal to 100K U / g, the enzyme activity of the papain is greater than or equal to 100K U / g, and the enzyme activity of the pectinase is greater than or equal to 50K U / g.

[0023] Good enzyme activity can ensure the thoroughness of enzyme-catalyzed chemical reactions, guarantee the conversion rate of the reaction, and improve the purity of the extract.

[0024] Preferably, the addition amount of the brown algae extract is 1-3 g / L.

[0025] An appropriate amount of brown algae extract can promote the growth of Spirulina, improve Spirulina's resistance to stress, and promote plant nutrient absorption.

[0026] The method for using the above-mentioned nutrient agent comprises: adding the basic nutrient agent and the brown algae extract into tap water, and dissolving them to form a spirulina culture solution.

[0027] The present application uses tap water to dilute and prepare the nutrient agent, wherein the tap water contains a small amount of trace elements (vanadium, nickel, tungsten, titanium, cobalt), which can be used as trace elements in the spirulina culture solution. On the basis of the above-mentioned nutrient agent formula of the present application, a small amount of trace elements in tap water is used as a supplement, which can not only meet the growth needs of Spirulina, but also simplify the nutrient agent formula. At the same time, tap water is easy to obtain and has a low cost, which improves the convenience of preparing the Spirulina nutrient agent of the present application.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows: the spirulina nutrient provided by the present invention contains a variety of nutrient elements required for the growth of spirulina, such as carbon, nitrogen, and phosphorus, to ensure the nutrient supply required for the growth process of spirulina, and to promote the growth and reproduction of spirulina plants. The brown algae extract contains rich active substances such as brown algae oligosaccharides and brown algae polyphenols, which can increase the growth rate of spirulina, enhance the stress resistance of spirulina, and promote nutrient absorption. Brown algae polyphenols have antioxidant, antibacterial, and antiviral activities. By adding brown algae extract, the absorption and utilization rate of spirulina to nutrient elements can be improved, the growth and reproduction rate of spirulina can be increased, and the yield and high temperature resistance of spirulina can be further improved. In the process of cultivating spirulina, environmental factors such as high temperature can easily have an adverse effect on the growth and cell integrity of spirulina. Active substances such as brown algae oligosaccharides and brown algae polyphenols in the spirulina extract can protect spirulina from keeping its cell wall intact during the cultivation process, improve the adaptability of spirulina to the environment, and avoid the problems of fishy smell and poor taste of fresh spirulina.

[0029] The spirulina nutrient of the present application can be prepared into a compound liquid preparation, powder or a compound liquid preparation + powder, and only needs to be dissolved in water when used. The operation is simple and convenient for non-professionals to operate. Spirulina can be cultivated at home and eaten immediately after harvesting, thus avoiding the loss of nutrition during the circulation and processing of spirulina, and has great market application prospects. DETAILED DESCRIPTION

[0030] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention. Modifications or substitutions made to the methods, steps or conditions of the present invention without departing from the spirit and essence of the present invention are within the scope of protection of the present invention. Unless otherwise specified, the experimental materials, reagents, instruments, etc. used in the examples of the present invention are all commercially available; unless otherwise specified, all technical means in the examples of the present invention are conventional means well known to those skilled in the art.

[0031] The following is a method for preparing the brown algae extract in an embodiment of the present invention:

[0032] Preliminary preparation: Soak the dried brown algae in water to rehydrate them or rinse the fresh brown algae with water, and crush them into algae pulp ≥ 200 mesh;

[0033] Primary enzymatic hydrolysis: add 3-3.5 times the mass of water to the algae pulp and stir, adjust the pH to 4.5-5.0, raise the temperature to 50-55°C, add ≥11% of the mass of the algae pulp cellulase and ≥1.8% of the mass of the algae pulp xylanase, and perform enzymatic hydrolysis for at least 5 hours;

[0034] Secondary enzymatic hydrolysis: adjust the pH of the solution after primary enzymatic hydrolysis to 6.0-7.0, maintain the temperature at 50-55°C, add ≥1.6% of the mass of algae pulp papain and keep stirring, and perform enzymatic hydrolysis for at least 5 hours;

[0035] Third-stage enzymatic hydrolysis: adjust the pH of the solution after the second-stage enzymatic hydrolysis to 4.5-5.0, maintain the temperature at 50-55°C, add ≥1.6% of the mass of algae pulp pectinase and keep stirring, and perform enzymatic hydrolysis for at least 5 hours;

[0036] Centrifugation: After centrifuging the solution after the tertiary enzymatic hydrolysis, the brown algae extract with a concentration density of ≥1.05g / ml is obtained.

[0037] The temperature will change during enzymatic hydrolysis and needs to be kept within an appropriate range; pH is adjusted using low concentrations of inorganic acids and inorganic bases, such as HCl, NaOH, etc., to prevent the reaction from being terminated; generally, the concentration is less than 3wt%.

[0038] Furthermore, the enzyme activities of papain, cellulase and xylanase are ≥100K U / g; and the enzyme activity of pectinase is ≥50K U / g.

[0039] Comparative Example 1 Effect of Spirulina culture solution prepared with basic nutrients on the growth of Spirulina at room temperature

[0040] Use a 15-liter round glass tank as a culture container, add 14 liters of tap water and basic nutrients into the tank, and after the basic nutrients are completely dissolved, it becomes the basic culture solution for Spirulina. Add 10 grams of Spirulina algae, use an aerator to provide oxygen, and a 9W LED lamp as a supplementary light source. Place the glass tank in a well-lit location such as a window or balcony indoors for normal temperature culture (the initial temperature of the culture solution is about 32°C in summer). The formula of the basic nutrient is: 9.80 grams of sodium nitrate, 3.61 grams of potassium dihydrogen phosphate, 9.05 grams of potassium sulfate, 11.45 grams of sodium chloride, 0.90 grams of EDTA-Ca (calcium sodium ethylenediaminetetraacetate), 0.34 grams of EDTA-Fe (sodium iron ethylenediaminetetraacetate), 0.34 grams of EDTA-Zn (sodium zinc ethylenediaminetetraacetate), 0.033 grams of EDTA-Mn (sodium manganese ethylenediaminetetraacetate), 0.0016 grams of EDTA-Cu (sodium copper ethylenediaminetetraacetate), 3.27 grams of EDTA-Mg (sodium magnesium ethylenediaminetetraacetate), 0.025 grams of boric acid, 0.0008 grams of ammonium heptamolybdate, 2.5 grams of urea, and 168 grams of sodium bicarbonate.

[0041] OD was measured every morning. 560 , when OD 560 When the OD value reaches 0.5 for the first time, start harvesting. Use a water pump to pump water for 1 minute each time, and pass it through a 200-mesh filter. Spirulina larger than 200 mesh will remain on the filter. The filtrate will flow back into the glass tank. Weigh the fresh weight of the spirulina remaining in the filter. After that, harvest once a day. When a large amount of spirulina adheres to the wall of the glass tank or the spirulina begins to turn yellow, harvest all of it. Record the average OD value of the harvested spirulina. 560 Value, harvest fresh weight.

[0042] Example 1 Effect of Spirulina culture solution prepared with basic nutrient and brown algae extract 1g / L on the growth of Spirulina at room temperature

[0043] The difference between this embodiment and comparative example 1 is that 14 grams of brown algae extract is added to the basic nutrient formula, and the other steps are the same as those of comparative example 1.

[0044] Example 2 Effect of Spirulina culture solution prepared with basic nutrient and brown algae extract 2g / L on the growth of Spirulina at room temperature

[0045] The difference between this embodiment and comparative example 1 is that 28 grams of brown algae extract is added to the basic nutrient formula, and the other steps are the same as those of comparative example 1.

[0046] Example 3 Effect of Spirulina culture solution prepared with basic nutrient and brown algae extract 3g / L on the growth of Spirulina at room temperature

[0047] The difference between this embodiment and comparative example 1 is that 42 grams of brown algae extract is added to the basic nutrient formula, and the other steps are the same as those of comparative example 1.

[0048] Example 4 Effect of Spirulina culture solution prepared with basic nutrient and brown algae extract 3g / L on the growth of Spirulina at room temperature

[0049] The difference between this embodiment and embodiment 3 is that the weight parts of the components in the basic nutrient formula used are as follows: 7 grams of sodium nitrate, 2 grams of potassium dihydrogen phosphate, 17 grams of potassium sulfate, 16 grams of sodium chloride, 1.3 grams of EDTA-Ca, 0.5 grams of EDTA-Fe, 0.5 grams of EDTA-Zn, 0.04 grams of EDTA-Mn, 0.002 grams of EDTA-Cu, 5 grams of EDTA-Mg, 0.05 grams of boric acid, 0.001 grams of ammonium heptamolybdate, 2.5 grams of urea, and 98 grams of sodium bicarbonate.

[0050] The other steps of this embodiment are the same as those of Embodiment 3.

[0051] Example 5 Effect of Spirulina culture solution prepared with basic nutrient and brown algae extract 3g / L on the growth of Spirulina at room temperature

[0052] The difference between this embodiment and embodiment 3 is that the weight parts of the components in the basic nutrient formula used are as follows: 11 grams of sodium nitrate, 6 grams of potassium dihydrogen phosphate, 7 grams of potassium sulfate, 9 grams of sodium chloride, 0.7 grams of EDTA-Ca, 0.1 grams of EDTA-Fe, 0.1 grams of EDTA-Zn, 0.02 grams of EDTA-Mn, 0.001 grams of EDTA-Cu, 2 grams of EDTA-Mg, 0.01 grams of boric acid, 0.0006 grams of ammonium heptamolybdate, 0.6 grams of urea, and 238 grams of sodium bicarbonate.

[0053] The other steps of this embodiment are the same as those of Embodiment 3.

[0054] Result determination:

[0055] The average OD of Spirulina recorded in the above examples and comparative examples was 560 The values ​​and fresh weight of harvest were sorted and counted. The test results are shown in Table 1. From Table 1, it can be seen that:

[0056] (1)OD 560 The value represents the light-shielding ability of Spirulina. The higher the density of Spirulina, the stronger its light-shielding ability. The OD value at 560 nanometers is used to observe the growth of Spirulina. 560 The larger the value, the higher the density of Spirulina. 560 The values ​​of Examples 1-3 were all higher than those of Comparative Example 1, indicating that the addition of brown algae extract can promote the growth and reproduction of Spirulina and increase the density of Spirulina. 560 The values ​​increase successively, indicating that with the increase of the amount of brown algae extract added, the density of Spirulina also gradually increases.

[0057] (2) The fresh weights of Examples 1-5 were all higher than those of Comparative Example 1, indicating that the addition of brown algae extract can increase the yield of Spirulina. Furthermore, the yield of Spirulina in Examples 1 to 3 showed a gradually increasing trend, indicating that as the amount of brown algae extract added increased, the yield of Spirulina also increased. When the amount of brown algae extract added was 3 g / L, the yield of Spirulina was increased by 18.19% compared with the Spirulina culture solution prepared with the basic nutrient.

[0058] (3) The spirulina cultured in Comparative Example 1 smells fishy, ​​while the spirulina cultured in Examples 1-5 does not smell fishy, ​​indicating that the active substances such as brown algae oligosaccharides and brown algae polyphenols in the brown algae extract can protect the integrity of the cell wall of Spirulina during the cultivation process, enhance the adaptability of Spirulina to the environment, and prevent the cell wall of Spirulina from being damaged to produce fishy smell and affect the taste.

[0059] Table 1 Effect of brown algae extract addition on the growth of Spirulina under normal temperature

[0060]

[0061] Comparative Example 2 Effect of Spirulina culture solution prepared with basic nutrients on the growth of Spirulina under high temperature conditions

[0062] A 15-liter round glass cylinder is used as a culture container, and 14 liters of tap water and basic nutrients are added to the cylinder. After the basic nutrients are completely dissolved, the basic culture solution of Spirulina is obtained. 10 grams of Spirulina seeds are added, oxygen is provided by an aerator, three 9W LED lamps are used as light sources, and the glass cylinder is placed in a well-lit position such as a window or balcony indoors for normal temperature culture (the initial temperature of the culture solution is about 32°C in summer). The formula of the basic nutrients is: 9.80 grams of sodium nitrate, 3.61 grams of potassium dihydrogen phosphate, 9.05 grams of potassium sulfate, 11.45 grams of sodium chloride, 0.90 grams of EDTA-Ca, 0.34 grams of EDTA-Fe, 0.34 grams of EDTA-Zn, 0.033 grams of EDTA-Mn, 0.0016 grams of EDTA-Cu, 3.27 grams of EDTA-Mg, 0.025 grams of boric acid, 0.0008 grams of ammonium heptamolybdate, 2.5 grams of urea, and 168 grams of sodium bicarbonate.

[0063] When the Spirulina was first added, only one lamp was turned on as a light source, and the culture temperature was 34°C at noon. After 5 days, three lamps were turned on as a light source, and the culture temperature was 40°C at noon. OD was measured every morning. 560 When the OD is measured 560 When it reaches 0.5 for the first time, start harvesting. Use a bottled water pump to extract for 1 minute each time, pass through a 200-mesh filter. Spirulina larger than 200 mesh will remain on the filter, and the filtrate will flow back into the glass tank. Weigh the fresh weight of the spirulina remaining in the filter. After that, harvest once a day. When a large amount of spirulina appears on the wall of the glass tank or the spirulina begins to turn yellow, all of it is harvested. Record the spirulina harvesting time and average OD 560 value, Spirulina production,

[0064] Example 6 Effect of Spirulina culture solution prepared with basic nutrient and brown algae extract 1g / L on the growth of Spirulina under high temperature conditions

[0065] The difference between this embodiment and comparative example 2 is that 14 grams of brown algae extract is added to the basic nutrient formula, and the other steps are the same as those in comparative example 2.

[0066] Example 7 Effect of Spirulina culture solution prepared with basic nutrient and brown algae extract 2g / L on the growth of Spirulina under high temperature conditions

[0067] The difference between this embodiment and comparative example 2 is that 28 grams of brown algae extract is added to the basic nutrient formula, and the other steps are the same as those in comparative example 2.

[0068] Example 8 Effect of Spirulina culture solution prepared with basic nutrient and brown algae extract 3g / L on the growth of Spirulina under high temperature conditions

[0069] The difference between this embodiment and comparative example 2 is that 42 grams of brown algae extract is added to the basic nutrient formula, and the other steps are the same as those in comparative example 2.

[0070] Result determination:

[0071] The spirulina harvesting time and average OD recorded in Examples 6-8 and Comparative Example 2 were 560 The values ​​and fresh weight of harvest were sorted and counted. The test results are shown in Table 2. It can be seen from Table 2 that:

[0072] (1) The harvesting time of Examples 6-8 was extended compared with that of Comparative Example 2, indicating that the addition of brown algae extract can mitigate the effect of high temperature on the growth of Spirulina and appropriately extend the harvesting period. Among them, the harvesting time of adding 1g / L brown algae extract and adding 2g / L brown algae extract was equal; the harvesting time of adding 3g / L brown algae extract was more than 1.7 times that of the Spirulina culture solution prepared with the basic nutrient.

[0073] (2) OD of Examples 6-8 compared to Comparative Example 2 560 All of them increased, indicating that adding brown algae extract can alleviate the inhibitory effect of high temperature on the growth and reproduction of Spirulina; the OD 560 The values ​​increase successively, indicating that with the increase of the amount of brown algae extract added, the density of Spirulina also gradually increases. 560 The OD values ​​and those of Comparative Example 1 560 The values ​​are basically equal (all around 0.565), indicating that when the brown algae extract is added to 2g / L, it can basically offset the effect of 40℃ high temperature on the growth of Spirulina. When the addition of brown algae extract is increased to 3g / L, the growth and reproduction rate of Spirulina is faster than that of Spirulina culture solution prepared with basic nutrients under normal temperature conditions.

[0074] (3) The fresh weight of Examples 6-8 increased compared with that of Comparative Example 2, indicating that the addition of brown algae extract can reduce the effect of high temperature on the yield of Spirulina; the fresh weight of Spirulina harvested in Examples 6 to 8 showed a gradually increasing trend, indicating that with the increase in the amount of brown algae extract added, the fresh weight of Spirulina harvested also gradually increased. Comparing Table 2 with Table 1, it can be found that the fresh weight of Example 7 and the fresh weight of Comparative Example 1 are basically equal (both are about 232g), indicating that when the brown algae extract is added to 2g / L, it can basically offset the effect of 40°C high temperature on the yield of Spirulina; when the amount of brown algae extract added is increased to 3g / L, the yield of Spirulina is slightly increased compared with that under normal temperature conditions.

[0075] Table 2 Effect of brown algae extract addition on the growth of Spirulina under high temperature conditions

[0076]

[0077] The spirulina culture solution in the present application can be prepared into a compound liquid preparation, powder or powder + compound liquid preparation by preparing the nutrient agent, and it only needs to be dissolved in water when used. The operation is simple and convenient for non-professionals to operate. Spirulina can be cultivated at home and eaten immediately after being harvested, thus avoiding the loss of nutrition during the circulation and processing of spirulina, and has great market application prospects.

[0078] Specifically, the present application can weigh corresponding masses of sodium nitrate, potassium dihydrogen phosphate, potassium sulfate, sodium chloride, EDTA-Ca, EDTA-Fe, EDTA-Zn, EDTA-Mn, EDTA-Cu, EDTA-Mg, boric acid, ammonium heptamolybdate, urea, and sodium bicarbonate, dissolve them in tap water to prepare a concentrated solution with a higher concentration, and mix them with a corresponding mass of brown algae extract, so that the nutrient agent exists in the form of a compound liquid preparation. When culturing spirulina, it is only necessary to add the nutrient agent of the compound liquid preparation to the corresponding mass of tap water to dissolve it.

[0079] Alternatively, the present application can also concentrate and dry the brown algae extract into a powder, and then evenly mix it with sodium nitrate, potassium dihydrogen phosphate, potassium sulfate, sodium chloride, EDTA-Ca, EDTA-Fe, EDTA-Zn, EDTA-Mn, EDTA-Cu, EDTA-Mg, boric acid, ammonium heptamolybdate, urea, and sodium bicarbonate, so that the nutrient agent is in the form of a powder. When culturing spirulina, it is only necessary to add the powdered nutrient agent to tap water of corresponding mass to dissolve it.

[0080] Alternatively, you can also weigh a corresponding mass of sodium nitrate, potassium dihydrogen phosphate, potassium sulfate, sodium chloride, EDTA-Ca, EDTA-Fe, EDTA-Zn, boric acid, EDTA-Mn, EDTA-Cu, ammonium heptamolybdate, EDTA-Mg, urea and brown algae extract, dissolve them in tap water to prepare a high-concentration compound liquid preparation, weigh a corresponding mass of sodium bicarbonate, and package the compound liquid preparation and sodium bicarbonate separately to form a nutrient package of powder + compound liquid preparation. When culturing spirulina, you only need to add the nutrient package to the corresponding mass of tap water to dissolve it.

[0081] The present application uses tap water to dilute and prepare the nutrient agent, wherein the tap water contains a small amount of trace elements (vanadium, nickel, tungsten, titanium, cobalt), which can make up for the problem of insufficient trace elements in the basic nutrient agent of the present application. On the basis of the above-mentioned nutrient agent formula of the present application, a small amount of trace elements in tap water is used as a supplement, which can not only meet the growth needs of Spirulina, but also simplify the nutrient agent formula. At the same time, tap water is easy to obtain and has a low cost, which improves the convenience of configuring the Spirulina culture solution of the present application.

[0082] The beneficial effects of the present invention are as follows: the spirulina culture solution provided by the present invention contains a variety of nutrient elements required for the growth of spirulina, such as carbon, nitrogen, phosphorus, potassium, and trace elements, which ensure the nutrient supply required for the growth process of spirulina and promote the growth and reproduction of spirulina plants. The brown algae extract contains rich active substances such as brown algae oligosaccharides and brown algae polyphenols, which can increase the growth rate of spirulina, enhance the stress resistance of spirulina, and promote nutrient absorption. Brown algae polyphenols have antioxidant, antibacterial and antiviral activities. By adding brown algae extract, the absorption and utilization rate of spirulina to nutrient elements can be improved, the growth and reproduction rate of spirulina can be increased, and the yield and high temperature resistance of spirulina can be further improved. In the process of cultivating spirulina, environmental factors such as high temperature are likely to have an adverse effect on the growth and cell integrity of spirulina. The active substances in the spirulina extract can protect spirulina from keeping the cell wall intact during the cultivation process, avoiding the problems of fishy smell and poor taste of fresh spirulina. The spirulina culture solution of the present application can be prepared into a compound liquid preparation, powder or powder + compound liquid preparation by preparing the nutrient agent, and it only needs to be dissolved in water when used. The operation is simple and convenient for non-professionals to operate. Spirulina can be cultivated at home and eaten immediately after being harvested, thus avoiding the loss of nutrition during the circulation and processing of spirulina, and has great market application prospects.

[0083] It can be understood that the above embodiments only express the preferred implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the patent scope of the present invention. It should be pointed out that, for ordinary technicians in this field, the above technical features can be freely combined without departing from the concept of the present invention, and several deformations and improvements can be made, which all belong to the protection scope of the present invention. Therefore, all equivalent changes and modifications made to the scope of the claims of the present invention should belong to the coverage of the claims of the present invention.

Claims

1. A spirulina nutritional agent, characterized in that: It comprises a basic nutrient and brown algae extract, wherein the basic nutrient comprises a carbon source, a nitrogen source, a phosphorus source, a potassium source, a magnesium source, a calcium source, a sulfur source and trace elements.

2. A spirulina nutrient according to claim 1, characterized in that: The basic nutrient comprises the following nutrient elements in parts by weight: 7-11 parts of sodium nitrate, 2-6 parts of potassium dihydrogen phosphate, 7-17 parts of potassium sulfate, 9-16 parts of sodium chloride, 0.7-1.3 parts of EDTA-Ca, 0.1-0.5 parts of EDTA-Fe, 0.1-0.5 parts of EDTA-Zn, 0.02-0.04 parts of EDTA-Mn, 0.001-0.002 parts of EDTA-Cu, 2-5 parts of EDTA-Mg, 0.01-0.05 parts of boric acid, 0.0006-0.001 parts of ammonium heptamolybdate, 0.6-2.5 parts of urea, and 98-238 parts of sodium bicarbonate.

3. A spirulina nutrient according to claim 1, characterized in that: The basic nutrient includes the following nutrient elements in parts by weight: 9.80 parts of sodium nitrate, 3.61 parts of potassium dihydrogen phosphate, 9.05 parts of potassium sulfate, 11.45 parts of sodium chloride, 0.90 parts of EDTA-Ca, 0.34 parts of EDTA-Fe, 0.34 parts of EDTA-Zn, 0.033 parts of EDTA-Mn, 0.0016 parts of EDTA-Cu, 3.27 parts of EDTA-Mg, 0.025 parts of boric acid, 0.0008 parts of ammonium heptamolybdate, 2.5 parts of urea, and 168 parts of sodium bicarbonate.

4. A spirulina nutrient according to claim 1, characterized in that: The preparation method of the brown algae extract is as follows: S1: preparing brown algae slurry and adjusting pH and temperature, adding cellulase and xylanase for primary enzymatic hydrolysis; S2: adjusting the pH and temperature of the solution after the primary enzymatic hydrolysis, and adding papain for secondary enzymatic hydrolysis; S3: adjusting the pH and temperature of the solution after the secondary enzymatic hydrolysis, and adding pectinase for tertiary enzymatic hydrolysis; S4: taking the solution after the third-stage enzymatic hydrolysis and concentrating it by centrifugation to make the concentration of the concentrate greater than or equal to 1.05 g / ml, thereby obtaining a brown algae extract.

5. A spirulina nutrient according to claim 4, characterized in that: The pH adjusting reagent in step S1, step S2, step S3 and step S4 is an inorganic acid and / or an inorganic base with a concentration less than 3 wt%.

6. A spirulina nutrient according to claim 5, characterized in that: The inorganic acid is hydrochloric acid, and the inorganic base is sodium hydroxide.

7. A spirulina nutrient according to claim 4, characterized in that: The enzyme activities of the cellulase and xylanase are greater than or equal to 100K U / g, the enzyme activity of the papain is greater than or equal to 100K U / g, and the enzyme activity of the pectinase is greater than or equal to 50K U / g.

8. The spirulina nutrient according to claim 1, characterized in that: The addition amount of the brown algae extract is 1-3 g / L.

9. A method for using the Spirulina nutrient according to any one of claims 1 to 8, characterized in that: include: Add basic nutrients and brown algae extract to tap water and dissolve them to form Spirulina culture solution.

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