A method for cultivating selenium-enriched lentinus edodes

Abstract

The application provides a selenium-rich Lentinula edodes cultivation method and belongs to the technical field of Lentinula edodes cultivation in agricultural planting. The selenium-rich Lentinula edodes cultivation method is performed according to the following steps: inoculating Lentinula edodes strains into a solid culture medium to obtain activated Lentinula edodes spores; the selenium-rich nutrient solution is composed of the following components in parts by weight: 100-600ml of nano-selenium, 8-48g of sugar alcohol, 0.5-3mg of EDTA, 0.5-1mg of triacontanol and 1000ml of water; the selenium-rich nutrient solution is added into a master seed culture medium, the activated Lentinula edodes spores are inoculated into the master seed culture medium, and the master seed culture medium is cultured for 60-65d to obtain selenium-rich Lentinula edodes master seeds; the selenium-rich nutrient solution is added into a cultivation culture medium, the master seeds are inoculated into the cultivation culture medium, and the cultivation culture medium is cultured for 100-120d to obtain selenium-rich Lentinula edodes fungus bags. The cultivation method improves the selenium aggregation capacity and selenium enrichment rate of Lentinula edodes.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of Lentinula edodes cultivation in agricultural planting, and more particularly to a selenium-enriched Lentinula edodes cultivation method. BACKGROUND

[0002] Lentinula edodes, also known as Xianggu, Donggu, etc., belongs to the fungal kingdom, basidiomycetes, agaricus, white mushroom family and lentinula genus. It is not only rich in nutrients and delicious, contains various polysaccharides, vitamins and amino acids needed by human body, is a low-fat and high-protein healthy fungus, and also has the effects of improving immunity, anti-fatigue, anti-tumor, regulating blood sugar, etc., and is deeply favored by consumers, and the market demand is increasing. Lentinula edodes, originally from China, has a cultivation history of nearly a thousand years, and is the largest edible fungus in China.

[0003] Selenium is one of the essential trace elements for human life, and is called the "anti-cancer king", "heart guardian" and "natural detoxifier" of trace elements in the human body by scientists. It has been proved that more than 40 diseases such as Keshan disease, big bone disease, cancer, tumor, decreased immunity, cardiovascular and cerebrovascular diseases, diabetes, infertility, AIDS, cataract, etc. are related to selenium deficiency in the body. The investigation report of Chinese Nutrition Society shows that most areas in China are selenium-deficient areas, and the selenium element in natural food cannot meet the physiological needs of the human body. Inorganic selenium is toxic and not easily absorbed by the human body; the toxicity of organic selenium is much lower than that of inorganic selenium, and the bioavailability is high, so it has important food and health care value to convert inorganic selenium into organic selenium by artificial method. Using Lentinula edodes as a selenium-enriched carrier, inorganic selenium is converted into organic selenium which is safer in terms of toxicological safety, physiological activity and absorption rate, so that selenium and physiological active substances in Lentinula edodes synergistically enhance the nutritional and health care effects of Lentinula edodes, and has broad market prospects.

[0004] The existing Lentinula edodes selenium-enriched methods include production of raw materials rich in selenium by using selenium-enriched rice bran (CN201610209339.1) containing selenium ≥0.46 μg / g, selenium-enriched corn cob powder (CN201711273488.5) or adding inorganic selenium such as sodium selenite (CN201510957073.4), zinc selenate (CN201910049942.1) in the formula raw material to finally achieve the effect of selenium enrichment. The first method is simple to operate but not suitable for selenium-deficient areas, and the second method has the disadvantages of low absorption rate, high toxicity, etc. of inorganic selenium, so adding inorganic selenium not only cannot achieve the ideal selenium supplementation effect, but also pollutes the environment and has potential hazards. Therefore, how to improve the selenium accumulation capacity and selenium enrichment rate of Lentinula edodes is a problem to be solved at present. SUMMARY

[0005] In view of the above problems, the present application provides a selenium-enriched Lentinula edodes cultivation method, which improves the selenium accumulation capacity and selenium enrichment rate of Lentinula edodes.

[0006] The present application aims to provide a method for cultivating selenium-enriched Lentinula edodes, which is carried out according to the following steps:

[0007] Step 1, activation of Lentinula edodes strain

[0008] The Lentinula edodes strain is inoculated on a solid culture medium for activation culture for 7-10 days to obtain activated Lentinula edodes strain;

[0009] Step 2, preparation of selenium-enriched nutrient solution, which is composed of the following components: nanometer selenium 100-600 ml, sugar alcohol 8-48 g, EDTA 0.5-3 mg, triacontanol 0.5-1 mg, and water 1000 ml;

[0010] Step 3, preparation of master culture medium

[0011] The selenium-enriched nutrient solution in step 2 is added to the master culture medium, and the activated Lentinula edodes strain is inoculated in the master culture medium for culture for 60-65 days to obtain selenium-enriched Lentinula edodes master strain;

[0012] Step 4, preparation of cultivation medium

[0013] The selenium-enriched nutrient solution in step 2 is added to the cultivation medium, and the master strain is inoculated in the cultivation medium for culture for 100-120 days to obtain selenium-enriched Lentinula edodes fungus bag.

[0014] Preferably, the solid culture medium is composed of the following components: potato 200 g, glucose 10-15 g, soluble starch 5.0-8.0 g, beef extract 3.0-6.0 g, potassium dihydrogen phosphate 0.5-1.0 g, magnesium sulfate 0.5-0.8 g, selenium yeast 50-200 g, agar 12 g, and water 1000 mL.

[0015] Preferably, the selenium-enriched nutrient solution is prepared according to the following steps:

[0016] S1, weigh each component: nanometer selenium 100-600 ml, sugar alcohol 8-48 g, EDTA 0.5-3 mg, triacontanol 0.5-1 mg, and water 1000 ml;

[0017] S2, mix the nanometer selenium and sugar alcohol, then add water, heat to 55-85℃, and stir until completely dissolved to obtain a sugar alcohol selenium mixture;

[0018] S3, add EDTA to the sugar alcohol selenium mixture, heat to 55-85℃, and stir until completely dissolved to obtain a selenium-enriched chelate;

[0019] S4, add triacontanol to the selenium-enriched chelate, heat to 55-85℃, and stir until completely dissolved to obtain a selenium-enriched nutrient solution.

[0020] Preferably, in step 2, the sugar alcohol is mannitol, maltitol, and sorbitol in a mass ratio of 1.5-2:0.5-1:2-3.

[0021] Preferably, in step 3, the original culture medium is composed of the following components in mass percentage: oak wood chips 60-65%, bran 18%, lime 1%, gypsum 1%, and the rest is date wood chips, and the water content is 55%-60%.

[0022] Preferably, in step 3, the selenium-rich nutrient solution is added to the original culture medium at a ratio of 50-150 ml / kg.

[0023] Preferably, in step 4, the cultivation medium is composed of the following components in mass percentage: oak wood chips 50-60%, kiwi branches 5-10%, bran 18%, lime 1%, gypsum 1%, and the rest is date wood chips, and the water content is 55%-60%.

[0024] Preferably, in step 4, the selenium-rich nutrient solution is added to the cultivation medium at a ratio of 100-600 ml / kg.

[0025] Preferably, in step 4, the selenium-rich nutrient solution is added to the cultivation medium at a ratio of 600 ml / kg.

[0026] Compared with the prior art, the present application has the following beneficial effects:

[0027] (1) The present application uses nano-selenium and yeast selenium as selenium source, which has the advantages of safety, stability, high biological activity, easy absorption, etc. compared with inorganic selenium.

[0028] (2) The present application uses sugar alcohol as a carrier to chelate nano-selenium and sugar alcohol to form sugar alcohol selenium, which can effectively promote the growth and development of shiitake mushrooms, improve the quality and stress resistance.

[0029] (3) Using the chelating function of EDTA to chelate sugar alcohol selenium again, a slow-release selenium-rich nutrient agent is obtained, which can significantly improve the selenium accumulation ability of shiitake mushrooms and the selenium content of fruiting bodies.

[0030] (4) Triacontanol has a certain promoting effect on the yield of shiitake mushrooms, and can also promote the synthesis and accumulation of effective substances such as polysaccharides and proteins.

[0031] (5) The present application uses a circulating selenium enrichment method to add different selenium concentrations at different stages of shiitake mushroom primary, secondary, and tertiary strains to enrich selenium, which is beneficial to improve the selenium accumulation ability of shiitake mushrooms and the selenium content of fruiting bodies.

[0032] Biological preservation information

[0033] Anxiang No. 3, referred to as the lentinula edodes strain in the present application, has been preserved in the China General Microbiological Culture Collection Center (address: No. 1, Beichen West Road, No. 3, Chaoyang District, Beijing) on November 29, 2021, and the classification name is lentinula edodes; the preservation number is CGMCC No. 23884. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 For the growth of selenium-enriched lentinula edodes mycelium in Example 2;

[0035] Figure 2 For the fruiting performance of selenium-enriched lentinula edodes in Example 2;

[0036] Figure 3 For the selenium-enriched lentinula edodes cultivated in Example 2. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part 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 those skilled in the art without creative labor fall within the scope of protection of the present application.

[0038] The lentinula edodes strain used in the present application is Anxiang No. 3, which is preserved in the China General Microbiological Culture Collection Center, and the preservation number is CGMCC No. 23884.

[0039] Example 1

[0040] Step 1, lentinula edodes strain activation

[0041] A solid culture medium is prepared by using a basic medium formula, and the lentinula edodes strain is inoculated onto the solid culture medium for 10 days of activation culture at 25°C to obtain the activated lentinula edodes strain. The basic medium formula is as follows: basic medium preparation: potato 200 g, glucose 15 g, soluble starch 5.0 g, beef extract 5.0 g, potassium dihydrogen phosphate 1.0 g, magnesium sulfate 0.5 g, yeast selenium 50 g, agar 12 g, and water 1000 mL.

[0042] Note: The total selenium content in yeast selenium is 2000 mg / kg.

[0043] Step 2, preparation of selenium-enriched nutrient solution

[0044] The selenium-enriched nutrient solution formula is: nanometer selenium 100 mL, sugar alcohol 8 mg, EDTA 0.5 mg, triacontanol 0.5 mg, and water 1000 mL. The sugar alcohol is mannitol, maltitol, and sorbitol with a mass ratio of 1:1:2.

[0045] Note: The total selenium concentration in nano-selenium is 5000 mg / kg.

[0046] Preparation method:

[0047] (1) After the weighed nano-selenium is mixed with sugar alcohol and added to water, heating to 85°C and stirring for 15 min until completely dissolved, a sugar alcohol selenium mixture is obtained;

[0048] (2) After EDTA is added to the above sugar alcohol selenium mixture, heating to 85°C and stirring for 15 min until completely dissolved, a selenium-rich chelate is obtained;

[0049] (3) After tritriacontanol is added to the above selenium-rich chelate, heating to 85°C and stirring for 15 min until completely dissolved, a selenium-rich nutrient solution is obtained.

[0050] Step 3, preparation of stock culture medium

[0051] A high-temperature-resistant polyethylene cultivation bag with specifications of 14 cm x 28 cm x 0.005 cm is used, and the formula is oak sawdust 65%, jujube sawdust 15%, bran 18%, lime 1%, and gypsum 1%, with a water content of 55%-60%. The selenium-rich nutrient solution is added to the stock culture medium at an addition ratio of 100 ml / kg; the activated shiitake mushroom spores are inoculated into the stock culture medium, and cultured for 60 d to obtain the stock;

[0052] Step 4, preparation of cultivation medium

[0053] A high-temperature-resistant polyethylene cultivation bag with specifications of 17 cm x 60 cm x 0.006 cm is used, and the formula is oak sawdust 60%, kiwi branch 5%, jujube sawdust 15%, bran 18%, lime 1%, and gypsum 1%, with a water content of 55%-60%. The selenium-rich nutrient solution is added to the cultivation medium at an addition ratio of 100 ml / kg; the stock is inoculated into the cultivation medium, and cultured for 110 d to obtain the selenium-rich shiitake mushroom bag.

[0054] Step 5, sterilization, inoculation, and mushroom management are performed according to the conventional operation.

[0055] Example 2

[0056] The same as example 1, the difference is:

[0057] In step 2, the formula of the selenium-rich nutrient solution is: nano-selenium 200 ml, sugar alcohol 16 mg, EDTA 1.0 mg, tritriacontanol 0.5 mg, and water 1000 ml.

[0058] In step 4, the addition ratio of the selenium-rich nutrient solution in the cultivation medium is 200 ml / kg.

[0059] Example 3

[0060] The same as example 1, except that:

[0061] In step 2, the selenium-rich nutrient solution formula is: nano selenium 300ml, sugar alcohol 24mg, EDTA 1.5mg, triacontanol 0.5mg, water 1000ml.

[0062] In step 4, the addition ratio of the selenium-rich nutrient solution in the cultivation medium is 300ml / kg.

[0063] Example 4

[0064] The same as example 1, except that:

[0065] In step 2, the selenium-rich nutrient solution formula is: nano selenium 400ml, sugar alcohol 32mg, EDTA 2.0mg, triacontanol 1.0mg, water 1000ml.

[0066] In step 4, the addition ratio of the selenium-rich nutrient solution in the cultivation medium is 400ml / kg.

[0067] Example 5

[0068] The same as example 1, except that:

[0069] In step 2, the selenium-rich nutrient solution formula is: nano selenium 500ml, sugar alcohol 40mg, EDTA 2.5mg, triacontanol 1mg, water 1000ml.

[0070] In step 4, the addition ratio of the selenium-rich nutrient solution in the cultivation medium is 500ml / kg.

[0071] Example 6

[0072] The same as example 1, except that:

[0073] In step 2, the selenium-rich nutrient solution formula is: nano selenium 600ml, sugar alcohol 48mg, EDTA 3mg, triacontanol 1mg, water 1000ml.

[0074] In step 4, the addition ratio of the selenium-rich nutrient solution in the cultivation medium is 600ml / kg.

[0075] Example 7

[0076] Step 1, Lentinula edodes strain activation

[0077] The solid culture medium is prepared by using the basic medium formula, and the Lentinula edodes strain is inoculated on the solid culture medium for 7 days of active culture at 25°C to obtain the activated Lentinula edodes strain. The basic medium formula is as follows: basic medium preparation: potato 200 g, glucose 10 g, soluble starch 8.0 g, beef extract 3.0 g, potassium dihydrogen phosphate 0.5 g, magnesium sulfate 0.8 g, yeast selenium 50 g, agar 12 g, and water 1000 mL.

[0078] Note: The total selenium content in the yeast selenium is 2000 mg / kg.

[0079] Step 2, preparation of selenium-rich nutrient solution

[0080] The selenium-rich nutrient solution formula is: nanometer selenium 100 mL, sugar alcohol 8 mg, EDTA 0.5 mg, triacontanol 0.5 mg, and water 1000 mL. The sugar alcohol is mannitol, maltitol, and sorbitol with a mass ratio of 1.5:0.5:3.

[0081] Note: The total selenium concentration in the nanometer selenium is 5000 mg / kg.

[0082] Preparation method:

[0083] (1) After mixing the nanometer selenium and the sugar alcohol, add water, heat to 70°C, and stir for 15 min until completely dissolved to obtain a sugar alcohol selenium mixture;

[0084] (2) Add EDTA to the above sugar alcohol selenium mixture, heat to 70°C, and stir for 15 min until completely dissolved to obtain a selenium-rich chelate;

[0085] (3) Add triacontanol to the above selenium-rich chelate, heat to 70°C, and stir for 15 min until completely dissolved to obtain the selenium-rich nutrient solution.

[0086] Step 3, preparation of the original culture medium

[0087] A high-temperature-resistant polyethylene cultivation bag with a specification of 14 cm x 28 cm x 0.005 cm is used, and the formula is oak sawdust 60%, jujube sawdust 20%, bran 18%, lime 1%, and gypsum 1%, with a water content of 55%-60%. The selenium-rich nutrient solution is added to the original culture medium at an addition ratio of 50 ml / kg; the activated Lentinula edodes strain is inoculated in the original culture medium, and cultured for 65 days to obtain the original strain;

[0088] Step 4, preparation of the cultivation medium

[0089] The high-temperature resistant polyethylene cultivation bag with the specification of 17cmx60cmx0.006cm is used, and the formula is oak sawdust 50%, kiwi branch 8%, jujube sawdust 22%, bran 18%, lime 1%, and gypsum 1%, and the water content is 55%-60%. The selenium-rich nutrient solution is added into the cultivation medium, and the adding ratio of the selenium-rich nutrient solution in the cultivation medium is 600ml / kg; the original strain is inoculated into the cultivation medium, and cultivated for 100 days, so as to obtain the selenium-rich Lentinula edodes bag.

[0090] Step 5, sterilization, inoculation, and mushroom management are carried out according to the conventional operation.

[0091] Example 8

[0092] Step 1, activation of Lentinula edodes strain

[0093] The solid culture medium is prepared by using the basic medium formula, the Lentinula edodes strain is inoculated into the solid culture medium, and the activated Lentinula edodes strain is obtained after 8 days of cultivation at 25℃. The basic medium formula is as follows: basic medium preparation: potato 200g, glucose 12g, soluble starch 6.0g, beef extract 6.0g, potassium dihydrogen phosphate 0.8g, magnesium sulfate 0.7g, selenium yeast 50g, agar 12g, and water 1000mL.

[0094] Note: the total selenium content in the selenium yeast is 2000mg / kg.

[0095] Step 2, preparation of selenium-rich nutrient solution

[0096] The selenium-rich nutrient solution formula is: nanometer selenium 100mL, sugar alcohol 8mg, EDTA 0.5mg, triacontanol 0.5mg, and water 1000mL. The sugar alcohol is mannitol, maltitol, and sorbitol with a mass ratio of 1.7:0.6:2.7.

[0097] Note: the total selenium concentration in the nanometer selenium is 5000mg / kg.

[0098] Preparation method:

[0099] (1) after mixing the nanometer selenium and the sugar alcohol, adding water, heating to 55℃, and stirring for 15min until completely dissolved, a selenium-sugar alcohol mixture is obtained;

[0100] (2) after adding EDTA into the above selenium-sugar alcohol mixture, heating to 55℃, and stirring for 15min until completely dissolved, a selenium-rich chelate is obtained;

[0101] (3) after adding triacontanol into the above selenium-rich chelate, heating to 55℃, and stirring for 15min until completely dissolved, a selenium-rich nutrient solution is obtained.

[0102] Step 3, preparation of original strain culture medium

[0103] The high-temperature resistant polyethylene cultivation bag with the specification of 14cmx28cmx0.005cm is used, and the formula is oak sawdust 63%, jujube sawdust 17%, bran 18%, lime 1%, and gypsum 1%, and the water content is 55%-60%. The selenium-rich nutrient solution is added into the original strain culture medium, and the adding ratio is 100ml / kg; the activated shiitake strain is inoculated into the original strain culture medium, and the original strain is obtained after 62d of culture;

[0104] Step 4, preparation of cultivation medium

[0105] The high-temperature resistant polyethylene cultivation bag with the specification of 17cmx60cmx0.006cm is used, and the formula is oak sawdust 56%, kiwi branch 10%, jujube sawdust 14%, bran 18%, lime 1%, and gypsum 1%, and the water content is 55%-60%. The selenium-rich nutrient solution is added into the cultivation medium, and the adding ratio of the selenium-rich nutrient solution in the cultivation medium is 600ml / kg; the original strain is inoculated into the cultivation medium, and the selenium-rich shiitake fungus bag is obtained after 120d of culture.

[0106] Step 5, sterilization, inoculation, and mushroom management are carried out according to the conventional operation.

[0107] Comparative Example 1

[0108] The difference from Example 1 is that the selenium-rich nutrient solution is not added in steps 3 and 4, and only the same amount of water is added.

[0109] Table 1 Influence of different selenium concentrations on the growth and development of shiitake mushrooms

[0110]

[0111] Note: The selenium concentration refers to the selenium concentration in the selenium-rich nutrient solution; the full bag time refers to the number of days when the mycelium grows full of the fungus stick when the culture temperature is 22-26℃.

[0112] As can be seen from Table 1, with the increase of the selenium concentration, the full bag time of shiitake mushrooms gradually extends, the bag average yield gradually decreases, but the selenium content of the fruiting body gradually increases. Within the test range, when the selenium concentration is 600mg / kg, the selenium content of the shiitake fruiting body is the highest, which is 746mg / kg, indicating that the selenium accumulation capacity of shiitake mushrooms is improved.

[0113] With the increase of the selenium concentration, the pollution rate of shiitake mushrooms shows a trend of first decreasing and then increasing, and when the selenium concentration is 400mg / kg, the pollution rate is the lowest, which is 1.9%, indicating that the selenium-rich nutrient solution with appropriate concentration can improve the stress resistance of shiitake mushrooms.

[0114] Table 2 Existence form and effective components of selenium-rich shiitake mushrooms

[0115]

[0116]

[0117] As can be seen from Table 2, with the increase of selenium concentration, the contents of crude polysaccharide and crude protein in selenium-enriched Lentinula edodes also increase, indicating that selenium and polysaccharide and protein can synergistically enhance each other. With the increase of selenium concentration, the selenium contents in soluble polysaccharide and soluble protein in selenium-enriched Lentinula edodes also increase, but the selenium content in soluble polysaccharide is higher than that in soluble protein.

[0118] Example 9

[0119] Step 1, activation of Lentinula edodes strain

[0120] The solid culture medium is prepared by using the basic medium formula, and the Lentinula edodes strain is inoculated on the solid culture medium for 10 days of activation culture at 25°C to obtain the activated Lentinula edodes strain. The basic medium formula is as follows: basic medium preparation: potato 200 g, glucose 15 g, soluble starch 5.0 g, beef extract 5.0 g, potassium dihydrogen phosphate 1.0 g, magnesium sulfate 0.5 g, yeast selenium 50 g, agar 12 g, and water 1000 mL.

[0121] Note: the selenium content in yeast selenium is 2000 mg / kg.

[0122] Step 2, preparation of master culture medium

[0123] The high-temperature-resistant polyethylene cultivation bag with the specification of 14 cm x 28 cm x 0.005 cm is used, and the formula is oak sawdust 65%, jujube sawdust 15%, bran 18%, lime 1%, and gypsum 1%, with the water content of 55%-60%. The activated Lentinula edodes strain is inoculated in the master culture medium for 60 days of culture to obtain the master strain;

[0124] Step 4, preparation of cultivation medium

[0125] Preparation of tritriacontanol culture solution:

[0126] Potato 200 g, glucose 15 g, soluble starch 5.0 g, beef extract 5.0 g, potassium dihydrogen phosphate 1.0 g, magnesium sulfate 0.5 g, yeast selenium 50 g, agar 12 g, tritriacontanol 1 mg, and water 1000 mL.

[0127] The high-temperature-resistant polyethylene cultivation bag with the specification of 17 cm x 60 cm x 0.006 cm is used, and the formula is oak sawdust 60%, kiwi branch 5%, jujube sawdust 15%, bran 18%, lime 1%, and gypsum 1%, with the water content of 55%-60%. 100 mL of tritriacontanol culture solution is added to 1.8 kg of cultivation medium; the master strain is inoculated in the cultivation medium for 110 days of culture to obtain the selenium-enriched Lentinula edodes fungus bag.

[0128] Step 5, sterilization, inoculation, and mushroom management are performed according to the conventional operation.

[0129] Table 3 Effects of triacontanol on growth of Lentinula edodes

[0130] Ash / % Crude protein / % Crude fat / % Crude fibre / % Contamination / % Comparative Example 1 2.96 16.49 3.96 6.98 8.6 Example 9 3.39 18.93 3.89 7.14 5.7

[0131] As shown in Table 3, when the concentration of triacontanol added was 1.0 mg / L, the contents of ash, crude protein and crude fiber in Lentinula edodes were higher than those of the control group, and the contamination rate of the bag was lower than that of the control group, indicating that adding triacontanol at an appropriate concentration can promote the accumulation of dry matter in Lentinula edodes, improve the quality, and enhance the stress resistance.

[0132] Although preferred embodiments of the application have been described, those skilled in the art will be able to make additional changes and modifications without departing from the spirit and scope of the application. Therefore, the appended claims are intended to cover all such changes and modifications that fall within the scope of the application.

[0133] Obviously, various modifications and changes can be made to the present application by those skilled in the art without departing from the spirit and scope of the present application. Thus, it is intended that the present application embrace all such changes and modifications as fall within the scope of the appended claims and their equivalents.

Claims

1. A method for cultivating selenium-enriched shiitake mushrooms, characterized in that, Follow these steps: Step 1: Activation of Shiitake Mushroom Spawn The shiitake mushroom strain was inoculated onto a solid culture medium and activated for 7-10 days to obtain activated shiitake mushroom spawn. Step 2: Prepare selenium-enriched nutrient solution. The selenium-enriched nutrient solution consists of the following components: 100-600ml of nano selenium, 8-48g of sugar alcohol, 0.5-3mg of EDTA, 0.5-1mg of triacontanol, and 1000ml of water. Step 3: Preparation of the original culture medium Add the selenium-enriched nutrient solution from step 2 to the original culture medium, inoculate the activated shiitake mushroom spawn into the original culture medium, and culture for 60-65 days to obtain the selenium-enriched shiitake mushroom original culture. Step 4: Preparation of cultivation medium Add the selenium-enriched nutrient solution from step 2 to the cultivation medium, inoculate the original strain into the cultivation medium, and culture for 100-120 days to obtain selenium-enriched shiitake mushroom bags. The solid culture medium consists of the following components: 200 g potato, 10-15 g glucose, 5.0-8.0 g soluble starch, 3.0-6.0 g beef extract, 0.5-1.0 g potassium dihydrogen phosphate, 0.5-0.8 g magnesium sulfate, 50-200 g yeast selenium, 12 g agar, and 1000 mL water. Selenium-enriched nutrient solution is prepared according to the following steps: S1. Weigh out the following components: 100-600ml nano selenium, 8-48g sugar alcohol, 0.5-3mg EDTA, 0.5-1mg triacontanol, and 1000ml water; S2. After mixing nano-selenium with sugar alcohol, add it to water, heat to 55~85℃ and stir until completely dissolved to obtain a sugar alcohol-selenium mixture; S3. Add EDTA to the sugar alcohol selenium mixture, heat to 55~85℃ and stir until completely dissolved to obtain a selenium-enriched chelate; S4. Add triacontanol to the selenium-enriched chelate, heat to 55~85℃ and stir until completely dissolved to obtain a selenium-enriched nutrient solution. In step 2, the sugar alcohols are mannitol, maltitol, and sorbitol in a mass ratio of 1.5-2:0.5-1:2-3. In step 3, the original culture medium consists of the following components by mass percentage: 60-65% oak sawdust, 18% wheat bran, 1% lime, 1% gypsum, and the remainder is jujube sawdust, with a moisture content of 55%-60%.

2. The method for cultivating selenium-enriched shiitake mushrooms according to claim 1, characterized in that, In step 3, the addition ratio of selenium-enriched nutrient solution to the original culture medium is 50-150 ml / kg.

3. The method for cultivating selenium-enriched shiitake mushrooms according to claim 1, characterized in that, In step 4, the cultivation medium consists of the following components by weight percentage: 50-60% oak sawdust, 5-10% kiwi branches, 18% wheat bran, 1% lime, 1% gypsum, and the remainder is jujube sawdust, with a moisture content of 55%-60%.

4. The method for cultivating selenium-enriched shiitake mushrooms according to claim 1, characterized in that, In step 4, the addition ratio of selenium-enriched nutrient solution to the cultivation medium is 100-600 ml / kg.

5. The method for cultivating selenium-enriched shiitake mushrooms according to claim 1, characterized in that, In step 4, the selenium-enriched nutrient solution is added to the cultivation medium at a ratio of 600 ml / kg.

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