Cultivation method for increasing selenium content of black fungus

Abstract

The cultivation method for increasing the selenium content of the black fungus comprises a cultivation material for increasing the selenium content of the black fungus, and the cultivation material is formed by mixing a slow-release sodium chlorate composite material and a slow-release selenium-containing mineral substance material with carbon nutrition, nitrogen nutrition and mineral nutrition. Sodium chlorate and selenium are respectively prepared into specific slow release systems, and are slowly released in the cultivation material to react to generate a seleninic acid component which can be easily absorbed and utilized by the black fungus, so that the concentration of seleninic acid in the cultivation material is regulated, the growth of the black fungus is promoted, the yield of the black fungus is increased, the quality of the black fungus is remarkably improved, and the cultivation cost is reduced. The selenium content and the amino acid content in the black fungus are remarkably increased, the cultivation material can be used for seedling cultivation of black fungus strains with high selenium content, and high-quality black fungus strains with high selenium content are obtained through cultivation of the cultivation material.

Description

[0001] This invention is a divisional application of the patent application with the application number 202411581354.X and the invention title of "A Cultivation Material for Cultivating Selenium-Rich Auricularia auricula and Its Preparation Method". Technical Field

[0002] This invention relates to the technical field of edible mushroom cultivation, and specifically relates to a cultivation method for increasing the selenium content in Auricularia auricula. Background Art

[0003] Selenium is a very small but essential trace element in the human body. It has the following functions: Selenium can enhance immunity, has the function of scavenging oxygen free radicals, and eliminates toxins in the body; Selenium is an active component of glutathione peroxidase, which can prevent the oxidative damage of insulin β cells and ensure its normal function; It enhances and improves the digestive and absorption functions, promotes the normal function of the gastrointestinal tract such as wax gourd, prevents constipation, and prevents dyspepsia such as abdominal distension, abdominal pain, nausea, oil aversion, anorexia, etc.; Selenium is an important element for maintaining the normal function of the heart, has a protective and reparative effect on cardiac myocytes, and a decrease in the blood selenium level in the human body will lead to a decline in the function of scavenging free radicals in the body, resulting in the precipitation of harmful substances.

[0004] Auricularia auricula is a precious edible and medicinal colloidal fungus in China and is a recognized health food in the world. Auricularia auricula contains substances such as plant collagen and Auricularia auricula polysaccharide, and the content of protein, microorganisms, and iron in the dried Auricularia auricula variety is very high. In recent years, with the enhancement of people's awareness of nutrition and health care, the research on the selenium-rich cultivation of Auricularia auricula and its nutritional components has become more and more in-depth. However, for a long time, the content of organic selenium in the dried products of conventionally cultivated Auricularia auricula is generally low. Adding a selenium source to the cultivation substrate can, to a certain extent, increase the selenium content in Auricularia auricula, but there are the following technical problems: When adding a selenium source to the cultivation material, if the selenium content is small, different selenium compounds will be formed in the cultivation material due to environmental changes, resulting in low effective absorption of Auricularia auricula and less subsequent conversion into organic selenium. If a large amount of selenium source is introduced, the selenium content in the cultivation material will exceed the standard, causing Auricularia auricula to be poisoned during the growth process, inhibiting the growth of Auricularia auricula, and leading to a decline in the final yield and quality of Auricularia auricula. Summary of the Invention

[0005] Based on the above problems, the purpose of this invention is to provide a cultivation method for increasing the selenium content in Auricularia auricula, specifically to provide a cultivation material for increasing the selenium content in Auricularia auricula.

[0006] Another purpose of this invention is to provide a preparation method for the above-mentioned cultivation material for cultivating selenium-rich Auricularia auricula.

[0007] The purpose of this invention is achieved through the following technical solutions: A cultivation method for increasing the selenium content in Auricularia auricula, including a cultivation material for increasing the selenium content in Auricularia auricula, which is characterized in that: the cultivation material is prepared by mixing a slow-release sodium chlorate composite material and a slow-release selenium-containing mineral material with carbon nutrition, nitrogen nutrition, and mineral nutrition. The slow-release selenium mineral material is prepared by dissolving selenium powder, gypsum, superphosphate, potassium dihydrogen phosphate, calcium sulfate, diatomaceous earth, nano-silica, and surfactant OP-10 in ethanol to form suspension 2, and then filtering and drying to obtain a selenium mineral core material. Acrylic acid, butyl acrylate, and styrene are mixed to form a polymer monomer solution. A packaging material is obtained by adding the polymer monomer solution, silane coupling agent, and azodiisobutyronitrile to isopropanol, and then adding the slow-release selenium-containing mineral core material to obtain a crude slow-release selenium-containing mineral. Then, it is soaked and treated with Bis-Tris buffer solution to prepare a polymer-coated slow-release selenium-containing mineral material.

[0008] Since inorganic selenium is directly added to the cultivation material, elemental selenium is difficult to be effectively utilized, and it is difficult to form selenium-rich Auricularia auricula. Moreover, if the added concentration is too high, it will inhibit the growth of Auricularia auricula mycelium. At the same time, selenium poisoning is likely to occur during the subsequent growth process of Auricularia auricula. Selenium in the form of selenous acid is the most easily absorbed and utilized by Auricularia auricula, but if the concentration is too low, it is not conducive to the absorption of Auricularia auricula, and if the concentration is too high, it will inhibit the growth of the mycelium.

[0009] In the present invention, by forming a slow-release structure with selenium and mineral components, it is slowly released in the cultivation material. At the same time, the released selenium will react with the slow-release sodium chlorate at an appropriate pH to generate selenous acid and chlorine dioxide. Selenous acid-state selenium is more easily absorbed by Auricularia auricula and effectively converted into organic selenium, while chlorine dioxide plays a role in sterilization and disinfection during the growth process of Auricularia auricula, thus ensuring the healthy growth of Auricularia auricula. The slow release of selenium, the relatively low selenium content in the early stage, and the selenium environment formed by the unreacted selenium effectively promote the growth of Auricularia auricula mycelium. As the concentration of selenous acid gradually increases, the selenous acid formed in the cultivation material subsequently remains stable within a certain concentration range suitable for the growth of Auricularia auricula fruiting bodies, inhibiting the problem of too high selenium concentration in the cultivation material, avoiding selenium poisoning in Auricularia auricula, and at the same time providing a stable and continuous effective concentration for Auricularia auricula to absorb quickly.

[0010] The reaction formula of selenium and sodium chlorate is as follows: 4ClO3 - +4H + +Se=4ClO2+H2O+H2SeO3 In the present invention, by forming slow release of both sodium chlorate and minerals, the concentration changes of selenous acid and selenium in the cultivation material are adjusted, forming a special cultivation material environment. In addition, it is also found that the synchronous slow release of minerals and selenium effectively promotes the absorption of selenium by Auricularia auricula, and at the same time plays a promoting role in the growth of Auricularia auricula mycelium and fruiting bodies.

[0011] Further, in the suspension 2, by weight, 1 part of selenium powder, 18 - 20 parts of gypsum, 4 - 5 parts of superphosphate, 18 - 20 parts of potassium dihydrogen phosphate, 8 - 10 parts of calcium sulfate, 90 parts of diatomite, 10 parts of nano - silica, 20 parts of surfactant OP - 10 and 130 parts of ethanol are mixed and then heated to 50 - 60 °C, and stirred for 2 - 3 h while keeping warm to obtain a diatomite suspension modified with nano - silica.

[0012] Further, the mass ratio of the slow - release selenium - containing mineral core material, packaging material and water is 3:1:8 - 10. After stirring evenly, it is dried at 80 - 90 °C and then pulverized to obtain a crude slow - release selenium - containing mineral product.

[0013] Further, the slow - release sodium chlorate composite material is prepared by dissolving sodium chlorate in water to form a sodium chlorate solution, mixing and stirring diatomite, nano - activated carbon, surfactant OP - 10 and ethanol to prepare suspension 1, adding the sodium chlorate solution into suspension 1 to obtain a mixed solution, subjecting the mixed solution to vacuum filtration, drying the filtered solid to obtain a slow - release sodium chlorate core material, and then adding a packaging material and water to form a slow - release sodium chlorate material.

[0014] Further, by weight, in the sodium chlorate solution, sodium chlorate is 1 part and water is 5 parts. In suspension 1, diatomite is 25 - 27 parts, nano - activated carbon is 2 parts, surfactant OP - 10 is 3 parts, and ethanol is 195 parts.

[0015] Further, after diatomite, nano - activated carbon, surfactant OP - 10 and ethanol are mixed according to a mass ratio, they are heated to 50 - 60 °C and stirred for 2 - 3 h while keeping warm to form a diatomite suspension modified with nano - activated carbon.

[0016] Further, the mass ratio of the slow - release sodium chloride core material, packaging material and water is 2:1:10. It is dried and pulverized at 80 - 90 °C to obtain a slow - release sodium chlorate material.

[0017] Further, in the polymerization monomer solution, the mass ratio of acrylic acid, butyl acrylate and styrene is 1 - 1.2:2 - 2.5:1 - 1.2, and the mass ratio of isopropyl alcohol, polymerization monomer solution, silane coupling agent and azobisisobutyronitrile is 50 - 55:40 - 45:2:1.

[0018] Further, by weight, in the cultivation material, the carbon nutrition component is 12 - 20 parts, the nitrogen nutrition component is 8 - 14 parts, the slow - release sodium chlorate material is 0.8 - 1.2 parts, and the slow - release selenium - containing mineral material is 0.5 - 1 part.

[0019] Further, the carbon nutrition component is composed of glucose, fructose, sucrose, starch and wood chips according to a mass ratio of 2:1:2:3:30.

[0020] Further, the nitrogen nutrient component is composed of rice bran, soybean cake powder, amino acid, urea and rice husk in a ratio of 1:2:1:5:35.

[0021] Further, for the soaking treatment, the slow-release selenium-containing mineral bold is placed in Bis-Tris buffer solution, heated to 35-40 °C, soaked for 4-5 h, then filtered, and dried at 35-40 °C to obtain the slow-release selenium-containing mineral material.

[0022] A preparation method of a cultivation material for cultivating selenium-rich Auricularia auricula, which is characterized by comprising the following steps: Step 1, prepare a slow-release sodium chlorate composite material (1) Dissolve sodium chlorate in water to form a solution, mix diatomite, nano-activated carbon, surfactant OP-10 and ethanol and stir to prepare suspension 1, add the sodium chlorate solution to suspension 1 to obtain a mixed solution, subject the mixed solution to vacuum filtration, and dry the filtered solid to obtain a slow-release sodium chlorate core material; (2) Mix acrylic acid, butyl acrylate and styrene to form a polymer monomer solution, and add the polymer monomer solution, silane coupling agent and azodiisobutyronitrile to isopropanol to form a coating material; (3) Add the slow-release sodium chlorate core material to the coating material, add water and stir evenly, then dry and pulverize to obtain a slow-release sodium chlorate material; Step 2, prepare a slow-release selenium-containing mineral material (1) Mix selenium powder, gypsum, superphosphate, potassium dihydrogen phosphate, calcium sulfate, diatomite, nano-silica, surfactant OP-10 and ethanol to form suspension 2, subject suspension 2 to vacuum filtration, and dry the filtered solid to obtain a slow-release selenium-containing mineral core material; (2) Mix acrylic acid, butyl acrylate and propylene to form a polymer monomer solution, and add the polymer monomer solution, silane coupling agent and azodiisobutyronitrile to isopropanol to obtain a coating material; (3) Add the slow-release selenium-containing mineral core material to the coating material, add water and stir, then dry and pulverize in sequence to obtain a slow-release selenium-containing mineral bold, and then use Bis-Tris buffer solution for soaking treatment to prepare a polymer-coated slow-release selenium-containing mineral material; Step 3, prepare the Auricularia auricula cultivation material Mix the carbon nutrient component, nitrogen nutrient component, slow-release sodium chlorate material and slow-release selenium-containing mineral material and water to obtain the Auricularia auricula cultivation material, and bag it for standby.

[0023] Further, in the coating materials in Step 1 and Step 2, the mass ratio of acrylic acid, butyl acrylate and styrene is 1-1.2:2-2.5:1-1.2.

[0024] Further, the mass ratio of the isopropanol, the polymer monomer solution, the silane coupling agent and the azodiisobutyronitrile is 50 - 55:40 - 45:2:1.

[0025] Further, by weight, in the sodium chlorate solution in the first step, sodium chlorate is 1 part, water is 5 parts, diatomite in suspension 1 is 25 - 27 parts, nano-activated carbon is 2 parts, surfactant OP-10 is 3 parts, and ethanol is 195 parts.

[0026] Further, after the diatomite, nano-activated carbon, surfactant OP-10 and ethanol are mixed according to the mass ratio, the temperature is raised to 50 - 60 °C and kept warm and stirred for 2 - 3 h to form a diatomite suspension modified with nano-activated carbon.

[0027] Further, in the first step, the mass ratio of the slow-release sodium chloride core material, the packaging material and water is 2:1:10, and it is dried and pulverized at 80 - 90 °C to obtain the slow-release sodium chlorate material.

[0028] Further, in suspension 2 in the second step, by weight, 1 part of selenium powder, 20 parts of gypsum, 5 parts of superphosphate, 20 parts of potassium dihydrogen phosphate, 10 parts of calcium sulfate, 90 parts of diatomite, 10 parts of nano-silica, 20 parts of surfactant OP-10 and 130 parts of ethanol are mixed and then the temperature is raised to 50 - 60 °C and kept warm and stirred for 2 - 3 h to obtain a diatomite suspension modified with nano-silica.

[0029] Further, the mass ratio of the slow-release selenium-containing mineral core material, the packaging material and water is 3:1:8 - 10. After stirring evenly, it is dried at 80 - 90 °C and then pulverized to obtain the slow-release selenium-containing mineral bulk.

[0030] Further, for the soaking treatment, the slow-release selenium-containing mineral bulk is placed in a Bis-Tris buffer solution, the temperature is raised to 35 - 40 °C, the soaking time is 4 - 5 h, then it is filtered and dried at 35 - 40 °C to obtain the slow-release selenium-containing mineral material.

[0031] By using the Bis-Tris buffer solution for soaking treatment, the pH of the selenium slow-release environment is stabilized at 5.5 - 6.5. In this environment, sodium chlorate and selenium mainly react to form selenous acid. Selenium in the form of selenous acid is conducive to the absorption and utilization during the growth process of Auricularia auricula. In addition, this pH is also the optimal environment for the growth of Auricularia auricula, effectively promoting the growth of Auricularia auricula.

[0032] Further, by weight, the cultivation material contains 12 - 20 parts of carbon nutrient components, 8 - 14 parts of nitrogen nutrient components, 0.8 - 1.2 parts of slow-release sodium chlorate material, 0.5 - 1 part of slow-release selenium-containing mineral material, and 30 - 40 parts of water.

[0033] Further, the carbon nutrient components are composed of glucose, fructose, sucrose, starch, and wood chips in a mass ratio of 2:1:2:3:30.

[0034] Further, the nitrogen nutrient components are composed of rice bran, soybean cake powder, amino acids, urea, and rice husk in a ratio of 1:2:1:5:35.

[0035] Most specifically, a method for preparing a cultivation material for cultivating selenium-rich Auricularia auricula, characterized by comprising the following steps: Step 1: Prepare a slow-release sodium chlorate composite material (1) Prepare a sodium chlorate solution by mixing sodium chlorate and water in a mass ratio of 1:5. Mix diatomaceous earth, nano-activated carbon, surfactant OP-10, and ethanol in a mass ratio of 25-27:3:6:195, then heat to 50-60 °C, keep warm and stir for 2-3 h to form suspension 1. Add the sodium chlorate solution to suspension 1 and stir to mix evenly to obtain a mixed solution. Vacuum filter the mixed solution, and dry the filtered solid to obtain the slow-release sodium chlorate core material; (2) Mix acrylic acid, butyl acrylate, and styrene in a mass ratio of 1-1.2:2-2.5:1-1.2 to form a polymer monomer solution. Add the polymer monomer solution, silane coupling agent, and azobisisobutyronitrile to isopropanol at a temperature of 100-110 °C, and continue to keep warm and react for 1 h to form a packaging material. The mass ratio of isopropanol, polymer monomer solution, silane coupling agent, and azobisisobutyronitrile is 50-55:40-45:2:1; (3) Add the slow-release sodium chlorate core material to the packaging material, then add water and stir evenly, dry, and crush to obtain the slow-release sodium chlorate material. The mass ratio of the slow-release sodium chloride core material, packaging material, and water is 2:1:10, and dry at 80-90 °C; Step 2: Prepare a slow-release selenium mineral material (1) Mix 1 part of selenium powder, 20 parts of gypsum, 5 parts of superphosphate, 20 parts of potassium dihydrogen phosphate, 10 parts of calcium sulfate, 90 parts of diatomaceous earth, 10 parts of nano-silica, 20 parts of surfactant OP-10, and 130 parts of ethanol by weight, then heat to 50-60 °C, keep warm and stir for 2-3 h to obtain suspension 2. Vacuum filter suspension 2, and dry the filtered solid to obtain the slow-release selenium-containing mineral core material; (2) Mix acrylic acid, butyl acrylate, and styrene in a mass ratio of 1-1.2:2-2.5:1-1.2 to form a polymer monomer solution. Add the polymer monomer solution, silane coupling agent, and azobisisobutyronitrile to isopropanol at a temperature of 100-110 °C, and continue to keep warm and react for 1 h to form a packaging material. The mass ratio of isopropanol, polymer monomer solution, silane coupling agent, and azobisisobutyronitrile is 50-55:40-45:2:1; (3) Mix the slow-release selenium-containing mineral core material, packaging material, and water in a mass ratio of 3:1:8-10. After stirring evenly, dry at 80-90 °C, then crush to obtain the slow-release selenium-containing mineral crude product. Then place the slow-release selenium-containing mineral crude product in Bis-Tris buffer solution, heat up to 35-40 °C, soak for 4-5 h, then filter, and dry at 35-40 °C to obtain the slow-release selenium-containing mineral material; Step 3: Prepare the Auricularia auricula cultivation material The cultivation material, calculated by weight, consists of 12-20 parts of carbon nutrition component, 8-14 parts of nitrogen nutrition component, 1-2 parts of slow-release sodium chlorate material, 0.5-1 part of slow-release selenium-containing mineral material, and 30-40 parts of water. Mix them into the cultivation material and bag it for standby. Among them, the carbon nutrition component is composed of glucose, fructose, sucrose, starch, and wood chips in a mass ratio of 2:1:2:3:30, and the nitrogen nutrition component is composed of rice bran, soybean cake powder, amino acids, urea, and rice husk in a ratio of 1:2:1:5:35.

[0036] The present invention has the following technical effects: In the present invention, by separately preparing specific slow-release systems for sodium chlorate and selenium, after slow-release in the cultivation material, selenous acid components that are easily absorbed and utilized by Auricularia auricula are generated through reaction, regulating the concentration of selenous acid in the cultivation material, promoting the growth of Auricularia auricula, increasing the yield of Auricularia auricula while significantly improving the quality of Auricularia auricula. The selenium content and amino acid content in Auricularia auricula have both increased significantly. This cultivation material can be used for the seedling cultivation of high-selenium-content Auricularia auricula strains, and high-quality strains of high-selenium-content Auricularia auricula can be obtained through cultivation with this cultivation material. Specific embodiments

[0037] The present invention will be specifically described below through examples. It is necessary to point out here that the following examples are only used to further illustrate the present invention and cannot be understood as limiting the protection scope of the present invention. Those skilled in the art can make some non-essential improvements and adjustments to the present invention based on the above content of the present invention.

[0038] Example 1 A cultivation method for increasing the selenium content of Auricularia auricula, including cultivating the cultivation material for selenium-rich Auricularia auricula, which is prepared according to the following steps: Step 1: Prepare the slow-release sodium chlorate composite material (1) Prepare a sodium chlorate solution by mixing sodium chlorate and water in a mass ratio of 1:5. Mix diatomite, nano-activated carbon, surfactant OP-10, and ethanol in a mass ratio of 27:3:6:195, then heat up to 55 °C, keep warm and stir for 2.5 h to form suspension 1. Add the sodium chlorate solution to suspension 1 and stir to mix evenly to obtain a mixed solution. Vacuum filter the mixed solution, and dry the filtered solid to obtain the slow-release sodium chlorate core material; (2)Mix acrylic acid, butyl acrylate and styrene in a mass ratio of 1.2:2:1 to form a polymer monomer solution. Add the polymer monomer solution, silane coupling agent, and azobisisobutyronitrile to isopropyl alcohol at a temperature of 105°C, and continue to hold the temperature for reaction for 1 h to form the packaging material. The mass ratio of isopropyl alcohol, polymer monomer solution, silane coupling agent, and azobisisobutyronitrile is 52:44:2:1; (3)Add the slow-release sodium chlorate core material to the packaging material, then add water and stir evenly, and then dry and crush to obtain the slow-release sodium chlorate material. The mass ratio of the slow-release sodium chloride core material, packaging material, and water is 2:1:10, and dry at 80-90°C; Step 2: Prepare the slow-release selenium mineral material (1)According to parts by weight, mix 1 part of selenium powder, 20 parts of gypsum, 5 parts of superphosphate, 20 parts of potassium dihydrogen phosphate, 10 parts of calcium sulfate, 90 parts of diatomaceous earth, 10 parts of nano-silica, 20 parts of surfactant OP-10, and 130 parts of ethanol, and then heat up to 55°C, hold the temperature and stir for 2.5 h to obtain suspension 2. Vacuum filter suspension 2, and dry the filtered solid to obtain the slow-release selenium-containing mineral core material; (2)Mix acrylic acid, butyl acrylate and styrene in a mass ratio of 1.2:2:1 to form a polymer monomer solution. Add the polymer monomer solution, silane coupling agent, and azobisisobutyronitrile to isopropyl alcohol at a temperature of 105°C, and continue to hold the temperature for reaction for 1 h to form the packaging material. The mass ratio of isopropyl alcohol, polymer monomer solution, silane coupling agent, and azobisisobutyronitrile is 52:44:2:1; (3)Mix the slow-release selenium-containing mineral core material, packaging material, and water in a mass ratio of 3:1:9, stir evenly, dry at 85°C, then crush to obtain the slow-release selenium-containing mineral bulk. Then place the slow-release selenium-containing mineral bulk in Bis-Tris buffer solution, heat up to 40°C, soak for 4.5 h, then filter, and dry at 40°C to obtain the slow-release selenium-containing mineral material; Step 3: Prepare the Auricularia auricula cultivation material The cultivation material is formulated according to parts by weight. The carbon nutrition component is 15 parts, the nitrogen nutrition component is 10 parts, 1 part of the slow-release sodium chlorate material, 0.8 part of the slow-release selenium-containing mineral material, and 35 parts of water are mixed to form the cultivation material, which is bagged and reserved. Among them, the carbon nutrition component is glucose, fructose, sucrose, starch, and wood chips in a mass ratio of 2:1:2:3:30, and the nitrogen nutrition component is composed of rice bran, soybean cake powder, amino acids, urea, and rice husk in a ratio of 1:2:1:5:35.

[0039] Comparative Example 1 Compared with Example 1, the slow-release sodium chlorate material was not prepared, that is, Step 1 was not carried out, and the rest of the cultivation material formula was the same as that in Example 1.

[0040] Comparative Example 2 Compared with Example 1, the sodium chlorate component is not subjected to slow-release treatment, and the same amount of sodium chlorate as in Example 1 is directly added to the cultivation material without slow-release treatment.

[0041] Comparative Example 3 Compared with Example 1, in the preparation of the slow-release selenium-containing mineral material in Step 2, there is no subsequent soaking treatment, and the remaining steps are the same as those in Example 1.

[0042] Comparative Example 4 Compared with Example 1, when preparing the slow-release selenium core material, the suspension does not contain gypsum, superphosphate, potassium dihydrogen phosphate, and calcium sulfate, and the above components are directly added when mixing and preparing the cultivation material, and the remaining steps are the same as those in Example 1.

[0043] The cultivation materials prepared in Example 1 and each comparative example were bagged at 2.5 kg / bag, inoculated with the same Auricularia auricula strain after sterilization, and cultivated and managed under the same conditions. During the cultivation process, starting from after inoculation, the concentration change of selenous acid in the cultivation bags was detected every 15 days, and the results are shown in Table 1.

[0044] Table 1: Concentration change of selenous acid in the cultivation material during cultivation management

[0045] It can be seen that in the present invention, as the detection time increases, the selenious acid content in the cultivation medium gradually increases. In the early stage, due to the slow release of selenium and sodium chlorate, the concentrations of both selenium and selenious acid are relatively low, within the concentration range beneficial to the growth of Auricularia auricula mycelium, which plays a role in promoting mycelial growth. After 60 days, a relatively stable concentration range is formed, which is beneficial to the growth of Auricularia auricula fruiting bodies and the effective absorption of selenious acid. In Comparative Example 1, since sodium chlorate was not added, the slowly released selenium was difficult to be largely converted into selenious acid in the cultivation medium, which is more conducive to the growth of mycelium and is more easily absorbed and utilized by Auricularia auricula. Instead, it mainly accumulated in the cultivation medium in the form of selenium, which significantly inhibited the formation of mycelium. The adverse growth of mycelium also affected the growth of subsequent fruiting bodies. In Comparative Example 2, since sodium chlorate was not slowly released, the selenium slowly released in the initial stage directly reacted completely with a sufficient amount of sodium chlorate, generating a large amount of selenious acid, resulting in a rapid initial accumulation of selenious acid, exceeding the upper limit of the growth requirements and beneficial concentration of mycelium, which instead inhibited the growth of mycelium and the absorption and utilization of selenious acid during the growth of Auricularia auricula. In Comparative Example 3, due to the unsuitable pH, the reaction and conversion of sodium chlorate and selenium were relatively slow, resulting in a low concentration of selenious acid. As selenium was slowly released, elemental selenium and sodium chlorate slowly accumulated in the cultivation bag, and the concentration of selenious acid also did not meet the requirements. In Comparative Example 4, since the mineral components were not slowly released synchronously with selenium, the mineral environment in the cultivation medium was different. Although selenious acid with a suitable concentration was generated, the absorption of selenious acid by Auricularia auricula was not ideal, and selenious acid gradually accumulated in the cultivation medium.

[0046] During the cultivation process, a cultivation medium prepared by directly adding minerals without slow-release selenium mineral materials and slow-release sodium chlorate materials was used as the blank group for inoculation, and the same cultivation management was carried out as the control management. The relevant indicators such as the mycelial growth trend of Auricularia auricula, the yield of Auricularia auricula, and the selenium content in Auricularia auricula are shown in Table 2.

[0047] Table 2:

[0048] Note: The number of '+' for the mycelial growth trend represents the strength degree of the shape.

[0049] Although there is currently no limit regulation on the selenium content in edible fungi in the national standards of our country, there are limit regulations on the selenium content in edible fungi in the local standards of individual regions. For example, DB36 / T 566-2009 "Jiangxi Provincial Local Standard Classification Standard for Selenium Content in Edible Fungi" stipulates that the selenium content in edible fungi should not exceed 1.0 mg / kg. Therefore, taking this standard as the safety standard, the selenium content of the dried Auricularia auricula in the present invention is 0.47 mg / kg, which is within the safety standard range, and the yield is significantly increased by 11.70% compared with the blank group. In Comparative Example 2, the selenium content is 1.29 mg / kg, and the organic selenium content is only 92.4%. Whether from the selenium content or the organic selenium content, there is a certain risk to the human body. In Comparative Example 4, although the yield of Auricularia auricula is significantly increased compared with the blank group, the increase in selenium content is not obvious, and the organic selenium content is also low. Due to the influence of selenium accumulation, the mycelial growth in Comparative Example 1 and Comparative Example 3 is inhibited, and the yield of Auricularia auricula decreases. Moreover, due to the too low concentration of selenious acid in the cultivation material that is conducive to absorption, the selenium content in Auricularia auricula is not ideal. In addition, it can also be seen that the total amino acid content in the cultivated Auricularia auricula in Example 1 is significantly increased, and the proportion of essential amino acids for the human body reaches 45.28%, while that in the blank group is only 42.87%. In Comparative Examples 1-3, the proportion of essential amino acids in Auricularia auricula for the human body significantly decreases compared with the blank group.

[0050] Example 2 A preparation method of a cultivation material for cultivating selenium-rich Auricularia auricula, comprising the following steps: Step 1, prepare a slow-release sodium chlorate composite material (1) Prepare a sodium chlorate solution by mixing sodium chlorate and water at a mass ratio of 1:5. Mix diatomite, nano-activated carbon, surfactant OP-10 and ethanol at a mass ratio of 26:3:6:195, then heat to 50 °C, keep warm and stir for 3 h to form suspension 1. Add the sodium chlorate solution to suspension 1 and stir to mix evenly to obtain a mixed solution. Vacuum filter the mixed solution, and dry the filtered solid to obtain a slow-release sodium chlorate core material; (2) Mix acrylic acid, butyl acrylate and styrene at a mass ratio of 1: 2.5: 1.2 to form a polymer monomer solution. Add the polymer monomer solution, silane coupling agent and azobisisobutyronitrile to isopropanol at a temperature of 100 °C, and continue to keep warm and react for 1 h to form a coating material. The mass ratio of isopropanol, polymer monomer solution, silane coupling agent and azobisisobutyronitrile is 55:45:2:1; (3) Add the slow-release sodium chlorate core material to the coating material, then add water and stir evenly, dry and crush to obtain a slow-release sodium chlorate material. The mass ratio of the slow-release sodium chloride core material, coating material and water is 2:1:10, and dry at 80 °C; Step 2, prepare a slow-release selenium mineral material (1)Mix 1 part of selenium powder, 20 parts of gypsum, 5 parts of superphosphate, 20 parts of potassium dihydrogen phosphate, 10 parts of calcium sulfate, 90 parts of diatomite, 10 parts of nano-silica, 20 parts of surfactant OP-10 and 130 parts of ethanol by weight, then heat up to 50 °C and keep stirring for 3 h to obtain suspension 2. Vacuum filter suspension 2 and dry the filtered solid to obtain the slow-release selenium-containing mineral core material; (2)Mix acrylic acid, butyl acrylate and styrene in a mass ratio of 1: 2.5: 1.2 to form a polymerization monomer solution. Add the polymerization monomer solution, silane coupling agent and azobisisobutyronitrile to isopropyl alcohol at 100 °C, and continue to keep the temperature for reaction for 1 h to form the packaging material. The mass ratio of isopropyl alcohol, polymerization monomer solution, silane coupling agent and azobisisobutyronitrile is 55:45:2:1; (3)Mix the slow-release selenium-containing mineral core material, packaging material and water in a mass ratio of 3:1:8, stir evenly, dry at 90 °C, then crush to obtain the crude slow-release selenium-containing mineral. Then place the crude slow-release selenium-containing mineral in Bis-Tris buffer solution, heat up to 35 °C, soak for 5 h, then filter and dry at 35 °C to obtain the slow-release selenium-containing mineral material; Step 3: Prepare the Auricularia auricula cultivation material The cultivation material is composed of 12 parts of carbon nutrition component, 8 parts of nitrogen nutrition component, 2 parts of slow-release sodium chlorate material, 1 part of slow-release selenium-containing mineral material and 35 parts of water by weight. Mix them to form the cultivation material and bag it for standby. Among them, the carbon nutrition component is composed of glucose, fructose, sucrose, starch and wood chips in a mass ratio of 2:1:2:3:30, and the nitrogen nutrition component is composed of rice bran, soybean cake powder, amino acid, urea and rice husk in a ratio of 1:2:1:5:35.

[0051] The Auricularia auricula cultivated in this example has a 12.14% increase in yield compared with the conventional cultivation material (adding slow-release selenium mineral material and slow-release sodium chlorate material, and directly adding mineral components to the cultivation material). The selenium content reaches 0.42 mg / kg of dry ear, the amino acid content reaches 126.49 mg / g, and the proportion of essential amino acids for the human body reaches 44.17%.

[0052] Example 3 A preparation method of a cultivation material for cultivating selenium-rich Auricularia auricula, comprising the following steps: Step 1: Prepare the slow-release sodium chlorate composite material (1) Prepare a sodium chlorate solution by mixing sodium chlorate and water at a mass ratio of 1:5. Mix diatomite, nano-activated carbon, surfactant OP-10, and ethanol at a mass ratio of 25:3:6:195, then heat to 60 °C and keep stirring for 2 h to form suspension 1. Add the sodium chlorate solution to suspension 1 and stir to mix evenly to obtain a mixed solution. Vacuum filter the mixed solution, and dry the filtered solid to obtain the slow-release sodium chlorate core material; (2) Mix acrylic acid, butyl acrylate, and styrene at a mass ratio of 1.1:2.2:1.1 to form a polymer monomer solution. Add the polymer monomer solution, silane coupling agent, and azobisisobutyronitrile to isopropanol at a temperature of 110 °C, and continue to keep the temperature for reaction for 1 h to form the packaging material. The mass ratio of isopropanol, polymer monomer solution, silane coupling agent, and azobisisobutyronitrile is 50:40:2:1; (3) Add the slow-release sodium chlorate core material to the packaging material, then add water and stir evenly, and then dry and crush to obtain the slow-release sodium chlorate material. The mass ratio of the slow-release sodium chloride core material, packaging material, and water is 2:1:10, and dry at 80 - 90 °C; Step Two: Prepare the slow-release selenium mineral material (1) Mix 1 part of selenium powder, 20 parts of gypsum, 5 parts of superphosphate, 20 parts of potassium dihydrogen phosphate, 10 parts of calcium sulfate, 90 parts of diatomite, 10 parts of nano-silica, 20 parts of surfactant OP-10, and 130 parts of ethanol by weight, then heat to 60 °C and keep stirring for 2 h to obtain suspension 2. Vacuum filter suspension 2 and dry the filtered solid to obtain the slow-release selenium-containing mineral core material; (2) Mix acrylic acid, butyl acrylate, and styrene at a mass ratio of 1.1:2.2:1.1 to form a polymer monomer solution. Add the polymer monomer solution, silane coupling agent, and azobisisobutyronitrile to isopropanol at a temperature of 110 °C, and continue to keep the temperature for reaction for 1 h to form the packaging material. The mass ratio of isopropanol, polymer monomer solution, silane coupling agent, and azobisisobutyronitrile is 50:40:2:1; (3) Mix the slow-release selenium-containing mineral core material, packaging material, and water at a mass ratio of 3:1:10, stir evenly, dry at 85 °C, then crush to obtain the slow-release selenium-containing mineral bulk. Then place the slow-release selenium-containing mineral bulk in Bis-Tris buffer solution, heat to 38 °C, soak for 4 h, then filter, and dry at 38 °C to obtain the slow-release selenium-containing mineral material; Step Three: Prepare the Auricularia auricula cultivation material The cultivation material, by weight, consists of 20 parts of carbon nutrition components, 14 parts of nitrogen nutrition components, 2 parts of slow-release sodium chlorate material, 0.5 part of slow-release selenium-containing mineral material, and 40 parts of water, which are mixed to form the cultivation material and bagged for standby. Among them, the carbon nutrition components are glucose, fructose, sucrose, starch, and sawdust in a mass ratio of 2:1:2:3:30, and the nitrogen nutrition components are composed of rice bran, soybean cake powder, amino acids, urea, and rice husk in a ratio of 1:2:1:5:35.

[0053] In this example, the yield of Auricularia auricula cultivated is 10.57% higher than that of the conventional cultivation material (with the addition of slow-release selenium mineral material and slow-release sodium chlorate material, and the mineral components are directly added to the cultivation material). The selenium content reaches 0.43 mg / kg of dry ear, and the amino acid content reaches 124.52 mg / g, among which the proportion of essential amino acids for the human body reaches 43.95%.

Claims

1. A cultivation method for increasing the selenium content in Auricularia auricula, including a cultivation material for increasing the selenium content in Auricularia auricula, characterized in that: The cultivation medium is prepared by mixing a slow-release sodium chlorate composite material and a slow-release selenium-containing mineral material with carbon nutrition, nitrogen nutrition, and mineral nutrition. The slow-release selenium mineral material is prepared by dissolving selenium powder, gypsum, superphosphate, potassium dihydrogen phosphate, calcium sulfate, diatomaceous earth, nano-silica, and surfactant OP-10 in ethanol to form suspension 2, filtering and drying the selenium mineral core material. Acrylic acid, butyl acrylate, and styrene are mixed to form a polymer monomer solution. A packaging material is obtained by adding the polymer monomer solution, silane coupling agent, and azobisisobutyronitrile to isopropanol. Then, the slow-release selenium-containing mineral core material is added to obtain a crude slow-release selenium-containing mineral material, which is then soaked and treated with Bis-Tris buffer solution to prepare a polymer-coated slow-release selenium-containing mineral material.

2. The cultivation method for increasing the selenium content of Auricularia auricula as described in claim 1, characterized in that: In suspension 2, by weight, 1 part of selenium powder, 18 - 20 parts of gypsum, 4 - 5 parts of superphosphate, 18 - 20 parts of potassium dihydrogen phosphate, 8 - 10 parts of calcium sulfate, 90 parts of diatomaceous earth, 10 parts of nano-silica, 20 parts of surfactant OP-10, and 130 parts of ethanol are mixed and heated to 50 - 60 °C, and kept stirring for 2 - 3 h to obtain a nano-silica-modified diatomaceous earth suspension.

3. The cultivation method for increasing the selenium content of Auricularia auricula as claimed in claim 1 or 2, characterized in that: The mass ratio of the slow-release selenium-containing mineral core material, the packaging material, and water is 3:1:8 - 10. After stirring evenly, it is dried at 80 - 90 °C, and then crushed to obtain a crude slow-release selenium-containing mineral material.

4. A cultivation method for increasing the selenium content of Auricularia auricula as described in any one of claims 1 to 3, characterized in that: The slow-release sodium chlorate composite material is prepared by dissolving sodium chlorate in water to form a sodium chlorate solution, mixing and stirring diatomaceous earth, nano-activated carbon, surfactant OP-10, and ethanol to prepare suspension 1, adding the sodium chlorate solution to the suspension to obtain a mixed solution, vacuum filtering the mixed solution, drying the filtered solid to obtain a slow-release sodium chlorate core material, and then adding the packaging material and water to prepare a slow-release sodium chlorate material.

5. The cultivation method for increasing the selenium content of Auricularia auricula as claimed in claim 4, characterized in that: By weight, in the sodium chlorate solution, 1 part of sodium chlorate and 5 parts of water, and in suspension 1, 25 - 27 parts of diatomaceous earth, 2 parts of nano-activated carbon, 3 parts of surfactant OP-10, and 195 parts of ethanol.

6. A cultivation method for increasing the selenium content of Auricularia auricula as described in any one of claims 1-5, characterized in that: After diatomaceous earth, nano-activated carbon, surfactant OP-10, and ethanol are mixed according to the mass ratio, they are heated to 50 - 60 °C and kept stirring for 2 - 3 h to form a nano-activated carbon-modified diatomaceous earth suspension.

7. A cultivation method for increasing the selenium content of Auricularia auricula as described in any one of claims 1-6, characterized in that: In the polymer monomer solution, the mass ratio of acrylic acid, butyl acrylate, and styrene is 1 - 1.2:2 - 2.5:1 - 1.2, and the mass ratio of isopropanol, the polymer monomer solution, the silane coupling agent, and azobisisobutyronitrile is 50 - 55:40 - 45:2:

1.

8. The cultivation method for increasing the selenium content of Auricularia auricula as claimed in claim 7, characterized in that: By weight, in the cultivation medium, the carbon nutrition component is 12 - 20 parts, the nitrogen nutrition component is 8 - 14 parts, the slow-release sodium chlorate material is 0.8 - 1.2 parts, and the slow-release selenium-containing mineral material is 0.5 - 1 part.

9. The cultivation method for increasing the selenium content of Auricularia auricula as claimed in claim 8, characterized in that: The carbon nutrition component is composed of glucose, fructose, sucrose, starch, and wood chips in a mass ratio of 2:1:2:3:

30.

10. A cultivation method for increasing the selenium content of Auricularia auricula as claimed in claim 8 or 9, characterized in that: The nitrogen nutrition component is composed of rice bran, soybean cake powder, amino acids, urea, and rice husk in a ratio of 1:2:1:5:35.

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