CN113597974A

CN113597974A - Edible fungus renewable culture medium, preparation method and application

Info

Publication number: CN113597974A
Application number: CN202110986058.8A
Authority: CN
Inventors: 胡玮; 邸青; 韦静宜; 陈红霞; 龙琦; 黄云峰
Original assignee: Chongqing Academy of Agricultural Sciences
Current assignee: Chongqing Academy of Agricultural Sciences
Priority date: 2021-08-26
Filing date: 2021-08-26
Publication date: 2021-11-05
Anticipated expiration: 2041-08-26
Also published as: CN113597974B

Abstract

The invention discloses a renewable edible fungus culture medium, a preparation method and application, and relates to the technical field of edible fungus culture. It includes: cottonseed hull, sawdust, wheat bran and biochar in a mass ratio of 5.2-8.2:4.3-6.8:2.4-3.9:1-1.8 in sequence. The edible fungus renewable culture medium provided by the invention not only can regenerate the waste fungus bags in a form of preparing biochar, but also can enable the renewable culture medium to have a better edible fungus hypha planting microstructure than that of a conventional culture medium. The method is beneficial to improving the yield of the edible fungi, shortening the cultivation period and providing a higher profit margin for the edible fungi producer.

Description

Edible fungus renewable culture medium, preparation method and application

Technical Field

The invention relates to the technical field of edible fungus cultivation, in particular to a renewable edible fungus cultivation substrate, a preparation method and application.

Background

Because the growth period of the edible fungi is short, the matrix updating and discarding frequency is high, and about 1500 ten thousand tons of waste edible fungi matrix are produced in China every year. The comprehensive utilization rate of the existing edible fungus culture medium is not more than 40%, most of the main edible fungus culture medium is disposable, namely, the edible fungus culture medium is discarded after one-time mushroom planting. This not only causes a great waste of resources but also causes environmental problems.

At present, methods for recycling edible fungus matrix waste are various, and comprise organic fertilizer production, fuel production, methane tank fermentation materials, animal feed production and the like. The method for preparing the organic fertilizer from the edible fungus substrate waste is the most widely applied recovery method and has the advantages of simplicity in operation, large treatment capacity and the like. But the application of the method is limited by the problems of long requirement period, large area, immature technology and the like, and the large-scale rapid treatment of the edible fungus substrate waste is difficult to realize.

In view of this, the invention is particularly proposed.

Disclosure of Invention

The invention aims to provide a renewable edible fungus culture medium, a preparation method and application to solve the technical problems.

The invention is realized by the following steps:

the invention provides a renewable edible fungus culture medium, which comprises: cottonseed hull, sawdust, wheat bran and biochar in a mass ratio of 5.2-8.2:4.3-6.8:2.4-3.9:1-1.8 in sequence.

The invention provides a renewable edible fungus culture medium, which not only can regenerate waste edible fungus substrates (namely waste fungus bags) by preparing biochar, but also can ensure that the renewable edible fungus culture medium has a microstructure for edible fungus hypha permanent planting better than that of a conventional culture medium. Specifically, the inventor finds that the edible fungus renewable cultivation substrate provided by the invention has the advantages of higher surface area, higher micropore volume, larger BJH pore volume and smaller average pore diameter. The substrate structure enables the culture substrate to have better water retention and ventilation capacity. In addition, the physical structural advantage can improve the growth of hyphae in the substrate, increase the yield of mushrooms, and accelerate the formation of fruit bodies. The inventor has learned through practice that: the edible fungus renewable culture medium has higher yield (20-25%) and faster harvesting time (4-6 days), which provides higher profit rate for the edible fungus producer. Therefore, the recycling of agricultural waste resources is facilitated on the basis of improving the yield and quality of the edible fungi.

In an alternative embodiment, the biochar accounts for 5-13% of the renewable cultivation substrate raw material of the edible fungi, and can be 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12% or 13% for example. The renewable culture substrate for the edible fungi comprises cottonseed hulls, sawdust, wheat bran and biochar in a mass ratio of 5.2-8.2:4.3-6.8:2.4-3.9:1-1.8 in sequence.

Through detection, compared with the conventional culture medium, the edible fungus renewable culture medium provided by the invention has the advantages that the volatile substances are reduced, the fixed carbon content is increased, the oxygen content is greatly reduced, the chemical stability is improved, and the requirement of recycling the edible fungus renewable culture medium can be met.

In addition, the edible fungus products planted by using the edible fungus renewable culture medium provided by the invention have no safety problem. Compared with the edible fungi planted by the conventional culture medium, the biological components are the same, and the content of pollutants in the food meets the national standard for food safety of GB 2762-.

Under the above-mentioned mass ratio conditions, the yield of edible fungi to be cultivated can be greatly increased, the formation of fruit bodies can be accelerated, and the harvesting time can be shortened.

In a preferred embodiment of the present invention, the biochar is formed by pyrolyzing waste edible fungus substrate or formed by pyrolyzing renewable edible fungus substrate again.

Edible fungi include, but are not limited to: lentinus edodes, straw mushroom, oyster mushroom, Hericium erinaceus, Tremella, Pleurotus geesteranus, Agaricus blazei Murr, bolete, Ganoderma, Auricularia, needle mushroom, Pleurotus eryngii, Coprinus comatus, Russula vinosa, Pleurotus nebrodensis, truffle or matsutake mushroom.

In other embodiments, the biochar can also be derived from agricultural and forestry waste, including agricultural waste selected from at least one of corn stover, reed straw, rice straw, and eggplant stalks, and forestry waste selected from at least one of fruit tree branches and garden tree branches.

In other embodiments, the agricultural and forestry waste may be selected from cotton stalks, bamboo willows, locust branches, and the like. In other embodiments, the agricultural and forestry waste is not limited to the types of agricultural and forestry waste listed above, and may be any type that can satisfy the requirement of producing biochar.

The inventor finds that the biochar formed by the secondary pyrolysis of the renewable substrate derived from the edible fungi can be reused and does not cause the technical advantages of yield, quality, safety or harvest time to disappear due to the increase of the recycling times.

Compared with the biochar formed by pyrolyzing the waste edible fungus substrate, the biochar formed by pyrolyzing the renewable edible fungus substrate (or the waste fungus bag) again does not have significant difference in micropore structure, environmental stability or influence on edible fungus cultivation. The edible fungus renewable substrate provided by the invention can be repeatedly and stably used in the production of edible fungi, and realizes the literal 'recycling'.

In a preferred embodiment of the application of the invention, the moisture content of the edible fungus renewable culture medium is 55-60%. In the actual use process, the water content of the edible fungus renewable culture substrate can be adaptively adjusted according to the edible fungus to be cultured. For example, it may be 55%, 56% or 58%.

In a preferred embodiment of the application of the invention, the pH of the edible fungus renewable culture medium is 6.5-7.

In a preferred embodiment of the application of the invention, the edible fungus renewable cultivation substrate further comprises a pH regulator, and preferably, the pH regulator is gypsum and calcium superphosphate.

For example, 1% gypsum and 1% calcium superphosphate is added for pH adjustment.

The invention also provides a preparation method of the edible fungus renewable culture substrate, which comprises the following steps: mixing the cottonseed hulls, the sawdust, the wheat bran and the biochar according to the mass ratio.

In a preferred embodiment of the present invention, the above preparation method comprises adjusting the pH of the regenerable cultivation substrate to 6.5-7 with a pH adjusting agent.

In a preferred embodiment of the present invention, the above preparation method further comprises the preparation of biochar; the preparation of the biochar comprises the following steps:

and carrying out anaerobic pyrolysis or partial oxygen-limited pyrolysis on the matrix waste of the edible fungi.

The pyrolysis is carried out for 2-3h at the temperature of 500-600 ℃;

and grinding the pyrolyzed biochar to form biochar with the average particle size of 2-3 mm.

In a preferred embodiment of the present invention, the preparation method further comprises sterilizing the mixture of the cottonseed hulls, the sawdust, the wheat bran and the biochar.

The invention also provides an application of the edible fungus renewable culture medium in edible fungus culture. Preferably, the application in the cultivation of edible fungi such as oyster mushroom, hericium erinaceus and the like.

The invention has the following beneficial effects:

the edible fungus renewable culture medium provided by the invention not only can regenerate the waste edible fungus medium by preparing the biochar, but also can enable the renewable culture medium to have a better microstructure for the permanent planting of edible fungus hyphae than the conventional culture medium.

The microstructure is represented by: the edible fungus renewable culture substrate provided by the invention has the advantages of higher surface area, higher micropore volume, larger BJH pore volume and smaller average pore diameter. The special substrate structure not only contributes to better water retention and ventilation capacity of the culture substrate. But also is beneficial to improving the growth of hypha in the substrate, improving the yield of the mushroom and accelerating the formation of the fruiting body. And further, the yield of the edible fungi is improved, and the harvesting time of the edible fungi is shortened, so that higher profit rate is provided for an edible fungi producer. Therefore, the recycling of agricultural waste resources is facilitated on the basis of improving the yield and quality of the edible fungi.

In addition, the edible fungus products planted by using the edible fungus renewable culture medium provided by the invention have no safety problem and have good edible fungus culture application prospects.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 shows the effect of different amounts of biochar (5%, 10% and 15%) on BET surface area of edible fungus culture substrate;

FIG. 2 is a graph showing the dynamic changes of pH (broken line) and moisture (column) of the edible fungus culture medium during the growth of mycelia and fruit bodies;

FIG. 3 is a graph of hyphal growth in various edible fungus substrates (hyphal as a percentage of the total surface area of the substrate);

FIG. 4 is a graph showing the aging phenomenon at the hyphal growth stage;

FIG. 5 is a diagram showing the results of NMR analysis of Pleurotus ostreatus cultured on a renewable substrate and a conventional substrate of edible fungi.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The features and properties of the present invention are described in further detail below with reference to examples.

Example 1

The embodiment provides a renewable edible fungus culture medium and a preparation method thereof. In the embodiment, the renewable cultivation substrate for the edible fungi comprises cottonseed hulls, sawdust, wheat bran and charcoal in a mass ratio of 8.2:6.8:3.9: 1. The biochar accounts for 5% of the total mass of the raw materials.

The preparation method comprises the following steps:

after putting the matrix waste of the edible fungi (in this example, the matrix waste of the oyster mushroom) into an oven at 85 ℃ for 6 hours, the dried sample was ground through a 1 mm sieve. The ground sample was then charged into a quartz tube furnace comprising a quartz crucible. The tube furnace was connected to a nitrogen supply to create anaerobic conditions throughout the pyrolysis process. After the tube furnace is started, the temperature is 25 ℃ for min^-1The temperature is raised to 500 ℃ at the temperature raising speed, and the pyrolysis is continued for 3 hours. And taking out the formed biochar sample after cooling to room temperature. The biochar is ground to a size of 2 mm to 3 mm.

Then mixing the cottonseed hulls, the sawdust, the wheat bran and the biochar in a mass ratio of 8.2:6.8:3.9:1 to prepare the culture medium. In addition, the pH of the matrix was adjusted to 6.5 by the addition of 1% gypsum and 1% calcium superphosphate. The main components of cottonseed hull, wheat bran and the like are fully mixed with the biochar, the water content is adjusted to 60%, and the substrate is packaged by a polyethylene plastic bag with the thickness of 18 multiplied by 45cm, so that the edible fungus renewable culture substrate is obtained. The substrate is sterilized under high pressure and cooled to room temperature, and then the substrate can be used for edible fungus inoculation cultivation.

Example 2

Compared with the embodiment 1, the difference is only that the renewable cultivation substrate of the edible fungi in the embodiment comprises the cotton seed hulls, the sawdust, the wheat bran and the biochar in the mass ratio of 5.8:4.8:2.7: 1.5. The biochar accounts for 10% of the total mass of the raw materials. The other preparation steps are the same, and the material sources are the same.

Example 3

Compared with the embodiment 1, the difference is only that the renewable cultivation substrate of the edible fungi in the embodiment comprises the cotton seed hulls, the sawdust, the wheat bran and the biochar in the mass ratio of 5.4:4.5:2.5: 2.2. The biochar accounts for 15% of the total mass of the raw materials. The other preparation steps are the same, and the material sources are the same.

Experimental example 1

In order to investigate the differences between this renewable substrate and the traditional substrate, cultivation trials of oyster mushroom (Pleurotus ostreatus) were carried out in mushroom growing houses equipped with intelligent monitoring systems.

The experimental design was as follows:

the experiment was run for 7 treatments, each: 1. the conventional matrix (CK) comprises cottonseed hulls, sawdust and wheat bran in a mass ratio of 8.4:7: 4; 2. a renewable substrate containing 5% by mass of biochar (T1, made by the method of making the renewable culture substrate of oyster mushroom of example 1); 3. a renewable substrate (T2, made by the method of making the flat renewable cultivation substrate of example 2) containing 10% by mass of biochar; 4. a renewable substrate (T3, made by the method of making the flat renewable cultivation substrate of example 3) containing 15% by mass of biochar; 5. a renewable substrate (RT1) containing 5% by mass of biochar (made from the used waste bag of renewable substrate for edible fungus cultivation of example 1); 6. a renewable substrate (RT2) containing 10% by mass of biochar (made from used waste bags of the cultivation of edible fungi of example 2); 7. renewable substrate (RT3) containing 15% by mass of biochar (made from used waste bag of edible fungi cultivation according to example 3). Each bag was filled with about 1.3kg of substrate and sterilized at 105 ℃ for 10 hours, and after autoclaving and cooling to room temperature, the bags were inoculated with oyster mushroom spawn (double anti-Heiping), 30 bags each being treated.

The biochar sources of T1-T3 are the same, and RT1-RT3 are the same, differing only in the amount of biochar.

The experimental example analyzes the physical and chemical properties of the culture substrate material.

The approximate compositions of regenerable culture substrates (RMS) and traditional substrates (CMS) were determined using a mettler-toledo TGA2 thermogravimetric analyzer. The C, H and N content of the mushroom substrate was measured by using elemental analysis. The specific surface area of the sample was determined by a Tristar II 3020 automated nitrogen specific surface area analyzer. The specific surface area of the sample was calculated by the BET equation.

The performance results of the renewable edible fungus substrate and the conventional substrate are shown in table 1, and it can be seen from table 1 that:

the RMS characteristics are very different from those of CMS due to the different amounts of biochar added. The analysis result of the substrate components shows that compared with CMS, the RMS has the advantages of reducing volatile substances, increasing the content of fixed carbon, greatly reducing the content of oxygen and improving the chemical stability, and can meet the requirement of recycling the renewable culture substrate of the edible fungi.

TABLE 1 comparison of the Performance of edible fungus renewable substrates with conventional substrates

Calculated as sample weight loss (100 wt% -volatile-ash-water)

Calculated as weight loss of sample (100 wt% -carbon-nitrogen-hydrogen-sulfur)

The microstructure analysis results of the renewable edible fungus matrix are shown in fig. 1 and table 2.

As can be seen from FIG. 1, the RMS treated surface areas were significantly higher than CMS, and the surface areas of the treatments increased exponentially with increasing biochar addition, with T3 and RT3 having 2631.07% and 2511.06% higher surface areas than CK, respectively.

Pore structure analysis for each treatment showed that the micropore volume, mesopore volume, and BJH pore volume for the RMS treatment group were all significantly higher than CMS, while the average pore diameter was significantly lower than CMS (table 2). This indicates that RMS has a better microstructure for colonization by hyphae of edible fungi than CMS.

TABLE 2 pore Structure parameters of different matrices

Different letters in the same column indicate significant differences (P <0.05).

Experimental example 2

Referring to seven treatments of experimental example 1, the experimental example continuously measures the moisture and the pH of the substrate material in the growth process of the edible fungi, and is used for evaluating the environmental stability of the renewable edible fungi substrate.

The pH and humidity of the substrate were measured every 4 days after inoculation of the fungus bags of each treatment group in Experimental example 1 until primordia of Pleurotus ostreatus appeared. Data were again recorded before the second harvest. The pH was measured using a pH meter and the humidity was recorded using a soil moisture sensor.

The substrate condition suitable for the growth of the oyster mushroom is 60-65% of moisture and 6.5-7 of pH value. Exceeding this range inhibits the growth of the mycelium and even the formation of fruiting bodies.

As can be seen from the experimental results in FIG. 2, the pH of each RMS treatment stabilized between 6.5 and 7 throughout the entire growth period. However, the pH of CK gradually decreased below 5, which is already below the optimal pH range for Pleurotus ostreatus growth, i.e., the growth of Pleurotus ostreatus in CK group was somewhat inhibited. While the RMS treated moisture was always maintained between 60-65%. However, CK treatment increased to 72.4% before the first harvest and dropped rapidly to 51.7% before the second harvest. This means that the RMS matrix has a unique structure with better water retention and ventilation than CMS.

Indicate that 20 days after inoculation, the partially processed edible fungi have primordia and need to be hydroentangled to grow mushroom normally. The remaining processing waits. Thus, the water jet time for each treatment after 20 days was not uniform and corresponding pH and water data were not collected. All data were obtained prior to hydroentanglement.

Indicates that the second recovery time was different because the first recovery time was not the same for each treatment. The final pH and moisture measurements are therefore determined by the actual harvest time for each treatment.

Experimental example 3

This example measured the hyphal growth and the yield of edible fungi with reference to seven treatments of example 1.

The growth of mushroom hyphae was measured according to the hypha colonization area of the substrate. Data were measured every 4 days after inoculation up to 28 days. Meanwhile, the whole growth process from inoculation to harvest of the oyster mushrooms is recorded visually by adopting time-lapse photography in the experimental example. Photographs of the edible mushroom substrate were taken every half hour for 28 days using a time delay camera. After the primordium is formed, the cover of the fungus bag is taken down, and the sporocarp of the edible fungus is allowed to develop. The yield of edible fungi was recorded for a total of two harvest cycles.

The experimental results show that mycelium of T1, T2, RT1 and RT2 can completely colonize the whole fungus pack within 20 days. Although the mycelium growth rate was initially fast, CK still required an additional 4 days (fig. 3). This was also confirmed by the first harvest time; that is, the use of RMS culture of edible fungi allowed the edible fungi to be harvested 4-6 days earlier than CMS (Table 3).

TABLE 3 yield and harvest time for cultivation of Pleurotus Ostreatus on different substrates

In order to describe more intuitively whether RMS or CMS is more beneficial for edible mushroom cultivation, time-lapse photography was used to observe the entire process from inoculation to harvest of oyster mushrooms. Video visually demonstrates the advantage of RMS in mushroom cultivation. Pleurotus ostreatus in RMS has significant advantages, both in terms of rate of hyphal colonization and in terms of fruiting body formation. At the same time, time-lapse photography reveals an interesting phenomenon. The CK treatment showed very marked hyphal aging at 13 days post inoculation, whereas the RMS treatment did not (FIG. 4).

This phenomenon occurs in about 5% of the mushroom bags in the oyster mushroom growing test. The aging of hyphae means that the hyphae gradually weakens or even disappears from the surface of the substrate when growing to the middle or bottom of the mushroom bag. As shown in table 3, RMS increased the total yield of pleurotus ostreatus and advanced the harvest time. The total yield of other RMS treatments, except the T3 and RT3 treatments, was 20-25% higher than CK, and the first harvest time was 4-6 days earlier. These results indicate that RMS can improve the growth of hyphae in the substrate, increase the yield of mushrooms, and accelerate the formation of fruiting bodies, thereby increasing the income of mushroom producers.

The yield of the T3 and RT3 treatments is reduced because the application amount of the biochar is too large, so that the carbon-nitrogen ratio of the substrate is too high, and the growth of edible fungi is inhibited.

Experimental example 4

The present example was subjected to metabolism and contaminant analysis with reference to seven treatments of example 1.

Experimental example 3 edible fungus sporocarp grown on different substrates were harvested and frozen in liquid nitrogen, then freeze-dried overnight. The lyophilized sample was ground. The sample was extracted with a mixture of 5mL 50% methanol and 5mL chloroform. Centrifuging the mixed solution, collecting the lower layer organic chloroform in a glass bottle, and vacuum-drying at high speed at-80 deg.C. Nuclear magnetic resonance was performed on a Bruker DRX-400 Advance (400MHz) spectrometer. Prior to analysis, the extracted metabolites were dissolved in 600ml of 99.8% chloroform-d and transferred to 6mm NMR tubes for organic metabolite detection. The concentration of contaminants in the edible fungi was determined using an atomic absorption spectrophotometer following the manufacturer's procedure.

In addition to yield, product safety is another important issue that needs attention. As shown in fig. 5, the absorption peaks of the hydrogen spectra for each RMS treatment are similar to the CK group, which means that there is no change between the metabolome groups for all mushroom samples. The data in table 4 also show that the pollutant levels for each treatment are within the national standards. The research result shows that the edible fungus produced by RMS has the same biological components as the edible fungus produced by CMS, and no toxic and harmful components possibly generated by using biochar are accumulated, thereby ensuring the safety of RMS.

It is noted that there is no significant difference in yield, quality, safety or harvest time between the RT and T treatments, indicating that RMS as a cultivation substrate for edible fungi can be reused as biochar and that the technical advantages in yield, quality, safety or harvest time are not lost due to the increased number of cycles.

TABLE 4 analysis table of contaminant content in Pleurotus ostreatus cultivated by RMS and CMS.

All data were from fresh samples.

The limit is indicated according to the pollutant limit in food safety national standard published by the national health commission of the people's republic of China GB 2762-.

Note that the data in the tables and figures in the above experimental examples are expressed as the mean ± standard deviation of all replicates. Statistical analysis of the data was performed by analysis of variance using statistical software (SAS version 9.2). Statistical significance was assessed using the Least Significant Difference (LSD) test (P <0.05). All figures were drawn using Origin2019 Pro.

The invention realizes the recycling of the waste edible fungus substrate and has positive significance for the whole edible fungus industry and environmental safety. Due to the advantages of the physical structure of the edible fungus renewable culture medium, the growth of hyphae in the medium can be improved, the yield of mushrooms can be increased, and the formation of fruiting bodies can be accelerated. The RMS formed by the edible fungus waste substrate biochar is made to have higher yield (20-25%) and faster harvest time (4-6 days) than CMS, which will provide higher profit margins for the edible fungus producer. Meanwhile, the edible fungus products planted by using the RMS have no safety problem. More importantly, the recovered RMS did not differ significantly from the original RMS in terms of cell structure, environmental stability or impact on edible fungus cultivation. This means that the RMS can be used repeatedly and stably in the production of edible fungi, and the literal 'recycling' is realized.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A renewable edible fungus culture medium is characterized by comprising: cottonseed hull, sawdust, wheat bran and biochar in a mass ratio of 5.2-8.2:4.3-6.8:2.4-3.9:1-1.8 in sequence.

2. The edible fungi renewable cultivation substrate according to claim 1, wherein the biochar is formed by pyrolyzing substrate waste of edible fungi or formed by pyrolyzing the renewable substrate derived from edible fungi again.

3. The edible fungus renewable cultivation substrate according to claim 1, wherein the water content of the edible fungus renewable cultivation substrate is 55-60%.

4. The edible fungus renewable cultivation substrate according to claim 3, wherein the pH of the edible fungus renewable cultivation substrate is 6.5-7.

5. The edible fungus renewable cultivation substrate according to claim 4, further comprising a pH adjusting agent, preferably said pH adjusting agent is gypsum and calcium superphosphate.

6. A method for preparing a renewable edible fungus culture medium according to any one of claims 1 to 5, comprising: mixing the cottonseed hulls, the sawdust, the wheat bran and the biochar according to the mass ratio.

7. The method of claim 6, comprising adjusting the pH of the regenerable cultivation substrate to 6.5-7 with a pH adjusting agent.

8. The method of claim 6, further comprising the preparation of biochar; the preparation of the biochar comprises the following steps:

carrying out anaerobic pyrolysis or partial oxygen-limited pyrolysis on the matrix waste of the edible fungi;

preferably, the pyrolysis is carried out for 2-3h at 500-600 ℃;

preferably, the pyrolyzed biochar is ground to form biochar with an average particle size of 2-3 mm.

9. The method of claim 6, further comprising sterilizing the mixture of cottonseed hulls, sawdust, wheat bran, and biochar.

10. Use of a regenerable edible fungus growth substrate of any one of claims 1-5 in the cultivation of edible fungi.