A method for preparing pure mycelium leather by solid-state fermentation

Abstract

The present invention discloses a method for preparing pure mycelium leather by solid-state fermentation, which belongs to the field of new materials technology. The present invention induces mycelium growth by optimizing the culture medium, changing the external environment, adding a scaffold, etc., thereby increasing the biomass of the mycelium, and then hot pressing, alkali treating, cross-linking, plasticizing, and coating the harvested mycelium blanket, and finally obtaining a vegan leather with performance strength comparable to that of animal leather and being environmentally friendly. The main process is divided into three steps. The first is to prepare solid seeds, which are then inoculated into a fermentation box while controlling the temperature, humidity, magnetic field, electric field, etc., and finally the harvested mycelium fiber composite material is hot pressed, alkali treated, cross-linked, plasticized, and coated. The fermentation process of the present invention and the process of preparation will not cause pollution to the environment, and the production cycle is short and the production cost is low.

Description

Technical Field

[0001] The invention relates to a method for preparing pure mycelium leather by solid-state fermentation, and belongs to the technical field of new materials. Background Art

[0002] Traditional animal leather production generates large amounts of wastewater and solid waste, causing significant environmental pollution. Furthermore, these leathers are difficult to degrade or reuse once discarded. Therefore, environmentally friendly and sustainable leather processing is of great importance. For over a century, filamentous fungi have been widely utilized for their high productivity and versatility. They are commonly used to produce enzymes and small molecule compounds such as antibiotics and organic acids, and their mycelium can also be used to produce packaging materials, construction materials, and more.

[0003] CN114901902A discloses fungal fabric materials and leather analogs. In addition to filamentous fungi, the material also includes plasticizers, polymers and cross-linking agents, and can be used as a leather substitute. However, CN114901902A grinds biomass and then mixes it with petroleum-based materials such as PVA to obtain a composite mycelium material, which has poor performance and feel. Summary of the Invention

[0004] In order to solve the above problems, the present invention prepares pure mycelium leather or mycelium fiber composite material through solid-state fermentation.

[0005] The first object of the present invention is to provide a method for preparing pure mycelium leather by solid-state fermentation. The pure mycelium leather refers to leather made by in-situ growth of mycelium and does not contain petroleum-based and animal-based ingredients. The method comprises the following steps:

[0006] (1) Activation of bacteria,

[0007] (2) Preparation of bacterial strains,

[0008] (3) Preparation of bacterial bags,

[0009] (4) Preparation of mycelium blanket:

[0010] The fungus bag obtained in step (3) was broken up and spread flat on the iron mesh at the top of the fermentation box. The external conditions were controlled so that the aerial hyphae grew downward through the iron mesh, entangled with each other, and completely covered the surface of the solid culture medium. After static cultivation for 7 days, the nutrient solution was sprayed downward from the bottom of the culture medium, that is, from the top of the fermentation box. After continuing to cultivate for 3 days, the surface mycelial blanket was harvested;

[0011] The external conditions include: temperature of 20-34°C, humidity of 40-100%, gas concentration of 78-90%, external electric field strength of 10-100 kV / m, external magnetic field strength of 10-100 mT, and light (red light 650 nm, green light 540 nm, or blue light 460 nm); the gas includes but is not limited to nitrogen, neon, hydrogen, and helium;

[0012] The nutrient solution is: 10 g / L soluble starch, 1.5 g / L soy peptone, 20 g / L glucose, 0.75 g / L potassium dihydrogen phosphate, 1.5 g / L magnesium sulfate, and 0.1 g / L vitamin B1;

[0013] When all nutrients are absorbed or the mycelium is mature enough, it will develop into a fruiting body, which is not conducive to or cannot be used to make leather. The growth of the fruiting body can be inhibited by controlling temperature, humidity, light, gas and spraying nutrient solution.

[0014] (5) Preparation of mycelium vegan leather:

[0015] The mycelium blanket obtained in step (4) is subjected to hot pressing, alkali treatment, cross-linking, plasticization and coating to obtain mycelium vegan leather.

[0016] In one embodiment of the present invention, the activation step of the bacterial strain in step (1) is as follows: 2 The fungus was inoculated on PDA medium and cultured at 28℃ for 4 days. 1 cm 2 The tip mycelium is inoculated onto a new PDA medium and culture is continued for 4 days, repeated three times to obtain a pure strain. The fungi include but are not limited to Ganoderma lucidum, Pleurotus ostreatus, Lentinus edodes, Volvariella volvacea, Oyster mushroom, Enoki mushroom, Hericium erinaceus, Pleurotus eryngii, Agaricus bisporus, Auricularia auricularia, Tremella fuciformis, Chanterelles, Morchella esculenta, Botrytis cinerea, Dictyophora indica, and Schizophyllum gracile. The medium is PDA medium: 200g of fresh potatoes are boiled for 15 minutes and filtered, 20g of glucose and 20g of agar are added, and after dissolution, the mixture is diluted to 1000ml and dispensed into 250ml conical flasks. After sterilization, the mixture is placed into sterile culture dishes while hot and cooled for later use.

[0017] In one embodiment of the present invention, the preparation of the bacterial strain in step (2) is as follows: 100 g of approximately 10 cm thin wooden strips are soaked in clean water for at least 48 hours, and after slightly drying, each thin wooden strip is evenly coated with 20 g of bran and 20 g of flour, sterilized, and cooled for later use. The pure bacterial strain obtained in step (1) is inoculated onto the thin wooden strips and cultured at 28°C for 8-10 days until the thin wooden strips are fully covered with mycelium.

[0018] In one embodiment of the present invention, the preparation step of the bacterial bag in step (3) is as follows: uniformly mixing exogenous nutrients with solid culture medium, dispensing the mixture into polypropylene fermentation bags, sterilizing and cooling the mixture, inserting the thin wood strips covered with mycelium obtained in step (2) into the fermentation bags, and culturing the mixture at 28°C for 10 days until the mycelium has completely grown in the polypropylene fermentation bags, thereby obtaining bacterial bags. The exogenous nutrients are at least one of potassium dihydrogen phosphate, calcium carbonate, glucose, magnesium sulfate, and yeast extract. Preferably, the exogenous nutrients are 1% potassium dihydrogen phosphate, 1% calcium carbonate, 10% glucose, and 1% magnesium sulfate. The solid culture medium is formulated to be at least one of flour, cottonseed hulls, corn cobs, bran, and sawdust, with a water content of 60-80%. Preferably, the solid culture medium is formulated to be 0-20 parts flour, 30-60 parts corn cobs, 10-30 parts bran, and 0-30 parts sawdust, with a water content of 70%.

[0019] In one embodiment of the present invention, the hot pressing shaping in step (5) is: hot pressing at a temperature of 80° C. and a pressure of 1 MPa for 1 minute.

[0020] In one embodiment of the present invention, the alkali treatment in step (5) refers to soaking in a sodium hydroxide aqueous solution with a mass fraction of 5 to 10% for 12 hours.

[0021] In one embodiment of the present invention, the cross-linking in step (5) is performed by placing the alkali-treated mycelium mat in a cross-linking agent having a mass fraction of 2 to 10% and soaking the mixture at 50° C. for 12 hours. The cross-linking agent comprises one or more of tannin extract, linseed oil, glutaraldehyde, genipin, formaldehyde, tyrosinase, acetic anhydride, sodium tripolyphosphate, or tannic acid.

[0022] In one embodiment of the present invention, the plasticizing step (5) comprises placing the cross-linked mycelium mat in a plasticizer having a mass fraction of 2 to 20% and soaking for 24 hours. The plasticizer comprises one or more of formamide, urea, sodium nitrate, salicylic acid, dicyandiamide, thiocyanate, glycerol, sorbitol, ethylene glycol, dioctyl sebacate, dibutyl phthalate, and DES.

[0023] In one embodiment of the present invention, the coating in step (5) includes but is not limited to PU coating, PVC coating, acrylic resin, phenolic resin coating, grease, silicone oil, shellac, and alcohol-soluble protein.

[0024] A second object of the present invention is to provide a method for preparing a mycelium fiber composite material, the method comprising the following steps:

[0025] (1) Mycelium fiber composite

[0026] Prepare the fungus bag by referring to steps (1)-(3) in the aforementioned “method for preparing pure mycelium leather by solid-state fermentation”;

[0027] The fiber blanket is soaked in the culture solution for more than 12 hours, taken out to dry, sterilized, and covered on the surface of the fungus bag after cooling. It is wrapped with plastic wrap and pierced on the surface to prevent rapid water loss. It is then placed in a 28°C incubator for 10 days. After 10 days, the mycelium will cover the fiber blanket. The fiber blanket is peeled off to obtain a mycelium-fiber composite.

[0028] The fiber blanket includes but is not limited to blankets woven with cotton fiber, linen fiber, viscose fiber, polyester fiber, regenerated cellulose fiber, and wool fiber;

[0029] The culture solution contains 10 g / L soluble starch, 1.5 g / L soy peptone, 20 g / L glucose, 0.75 g / L potassium dihydrogen phosphate, 1.5 g / L magnesium sulfate, and 0.1 g / L vitamin B1.

[0030] (2) Preparation of mycelium fiber composite materials

[0031] The mycelium fiber composite obtained in step (1) is cross-linked, plasticized, filled, hot-pressed, and coated to obtain a mycelium fiber composite material.

[0032] In one embodiment of the present invention, the crosslinking step comprises placing the hot-pressed mycelium-fiber composite in a crosslinking agent having a mass fraction of 2 to 10% and soaking the mixture at 50°C for 12 hours. The crosslinking agent comprises one or more of tannin extract, linseed oil, glutaraldehyde, genipin, formaldehyde, tyrosinase, acetic anhydride, sodium tripolyphosphate, or tannic acid.

[0033] In one embodiment of the present invention, the plasticizing step comprises placing the cross-linked mycelial fiber composite in a plasticizer having a mass fraction of 2 to 20% and immersing the composite for 24 hours. The plasticizer comprises one or more of formamide, urea, sodium nitrate, salicylic acid, dicyandiamide, thiocyanate, glycerol, sorbitol, ethylene glycol, dioctyl sebacate, dibutyl phthalate, and DES.

[0034] In one embodiment of the present invention, the filling comprises preparing a filler into a solution of a certain concentration, completely immersing the mycelium-fiber composite in the solution, soaking for 1 hour, and then removing and air-drying. The filler includes, but is not limited to, zein, wheat prolamin, hordein, kafirin, chitin nanowhiskers, carboxymethyl cellulose, aqueous polyurethane, and guar gum.

[0035] In one embodiment of the present invention, the hot pressing is performed at a temperature of 80° C. and a pressure of 1 MPa for 1 minute.

[0036] In one embodiment of the present invention, the coating includes but is not limited to PU coating, PVC coating, acrylic resin, phenolic resin coating, grease, silicone oil, shellac, and alcohol-soluble protein.

[0037] A third object of the present invention is to provide a method for the secondary utilization of discarded solid culture medium, comprising crushing the discarded solid culture medium and pressing it into a mold, incubating it at 28°C for 3-5 days, removing the mold after the incubation period, and placing the mycelium material in an oven to dry it at 50-100°C to obtain a mycelium buffer material. The discarded solid culture medium is the discarded substrate remaining after harvesting the surface mycelium carpet in step (4) of the aforementioned "method for preparing pure mycelium leather by solid-state fermentation"; the mold is used to help shape the mycelium buffer material. The mycelium buffer material can be used in packaging, construction and other fields.

[0038] Beneficial effects of the present invention:

[0039] The present invention utilizes in-situ growth of mycelium to obtain a complete mycelium sheet material, and performs hot pressing, cross-linking, and plasticization on the obtained mycelium sheet material to make it have the feel and performance of leather.

[0040] The present invention inhibits the growth of its fruiting body by controlling temperature, humidity, light, gas and spraying nutrient solution, thereby greatly improving the yield and performance of the mycelium, which can be directly used to process into mycelium vegan leather. A fiber blanket can also be used as a support, along which the mycelium grows, and the mycelium is used as a biological adhesive to adhere the fibers together. In addition, the mycelium leather obtained after a series of treatments such as cross-linking and plasticization has the same mechanical properties and strength as animal leather, and compared with the raw skins of pigs, cattle, sheep, etc. used in traditional leather making, the mycelium leather has a short production cycle, low cost, is biodegradable, and has little pollution to the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 : Schematic diagram of the fermentation box, ① substrate compartment; ② nitrogen inlet; ③ red light tube; ④ wire mesh; ⑤ spraying nutrient solution.

[0042] Figure 2 : Pure mycelium leather. DETAILED DESCRIPTION

[0043] Biomass test: per 1m 2 Dry weight of mycelial blanket.

[0044] Tensile Strength Test: Cut the mycelium leather into 8cm specimens and clamp the specimens at both ends in the upper and lower clamps of a tensile testing machine, keeping the specimens vertical and neither too tight nor too loose. The distance between the two clamps is 60mm, and the test speed is 500mm / min.

[0045] Folding performance test: Refer to the standard "QB / T2714-2005 Leather Physical and Mechanical Tests - Determination of Folding Fastness" and make appropriate modifications. Cut the sample into a 3cm square and fold it repeatedly in half. Observe the leather for creases and breaks. When the leather shows obvious signs of breaking, record the number of folds.

[0046] Degradability test: Take a portion of the degradable film and dry it to constant weight. Record the mass. Bury the film in soil 20-30 cm below the surface under natural conditions. Remove it after 50 days, rinse it with clean water, and dry it to constant weight. Calculate the weight loss rate W.

[0047] Example 1: Preparation of pure mycelium leather

[0048] (1): 1cm 2 The mushroom fruiting bodies were inoculated on PDA medium and cultured at 28℃ for 4 days. 1cm 2 The tip hyphae were inoculated on new PDA medium and cultured for 4 days, and repeated three times to obtain pure strains.

[0049] (2) Take 100g of thin wooden strips about 10cm in diameter and soak them in clean water for more than 48 hours. After drying slightly, evenly coat each strip with 20g of bran and 20g of flour. Sterilize and cool before use. Inoculate the strain from step (1) onto the thin wooden strips and incubate at 28°C for 8-10 days until the thin wooden strips are covered with mycelium.

[0050] (3) Prepare a solid culture medium. The solid culture medium formula (a) is: 40% corn cobs, 20% bran, 20% sawdust, 20% flour, and 70% water. The amounts of exogenous nutrients added to the solid culture medium are: 1% potassium dihydrogen phosphate, 1% calcium carbonate, 10% glucose, and 1% magnesium sulfate. The solid culture medium and exogenous nutrients are mixed evenly, dispensed into polypropylene fermentation bags, and sterilized at 121°C for 30 minutes. After cooling, the thin wooden strips covered with mycelium from step (2) are inserted into the culture medium and cultured at 28°C for 10 days.

[0051] (4): The mycelial bags covered with hyphae in step (3) were broken up and spread flat on the iron mesh at the top of the fermentation box. The culture conditions were: temperature 28°C, humidity 70%, nitrogen concentration 88%, red light (650nm) irradiation, electric field strength 30kV / m, and magnetic field strength 50mT. After 7 days of culture and fermentation, nutrient solution was evenly sprayed downward from the bottom of the culture medium, i.e., from the top of the fermentation box. Culture was continued for 3 days, and the mycelial carpet on the surface was harvested. The nutrient solution formula was: 10g / L soluble starch, 1.5g / L soy peptone, 20g / L glucose, 0.75g / L potassium dihydrogen phosphate, 1.5g / L magnesium sulfate, and 0.1g / L vitamin B1.

[0052] (5): Preparation of tannic acid / PEG solution: Take 1000 mL of water, add 5% tannic acid and 10% PEG-600.

[0053] Preparation of 5% zein solution: Take 5g of zein, add 95g of 65% ethanol solution, and stir at 40℃ for 3h until completely dissolved.

[0054] The mycelium mat obtained in step (4) was hot-pressed at 80° C. and 1 MPa for 1 min, then soaked in a 10% sodium bicarbonate solution for 8 h, and after washing away excess alkali solution, soaked in a tannic acid / glycerol solution for 24 h. After soaking, the mat was taken out and air-dried, and a 5% zein solution was evenly applied on the surface of the mycelium, and dried to obtain leather.

[0055] Example 2:

[0056] The specific implementation method is the same as that of Example 1, except that the culture medium formula a in step (3), i.e., 40% corn cobs, 20% bran, 20% sawdust, and 20% flour, is adjusted to:

[0057] Recipe B: corn cob 50%, bran 10%, sawdust 20%, flour 20%;

[0058] Recipe C: corn cob 30%, bran 20%, sawdust 30%, flour 20%;

[0059] Recipe d: corn cob 60%, bran 20%, flour 20%;

[0060] Recipe e: corn cob 30%, bran 30%, sawdust 20%, flour 20%;

[0061] Recipe f: corn cobs 40%, bran 30%, sawdust 30%.

[0062] Leather was prepared according to Example 1.

[0063] The mycelial carpet biomass in step (4) was detected, and the results are shown in Table 1 below:

[0064] Table 1

[0065] Recipe Number Recipe A Recipe B Recipe C Recipe d Recipe Recipe f Biomass (g) 142.3 123.4 114.2 132.6 102.8 129.8

[0066] When cultivating artificial spawn, common carbon sources include sawdust, cottonseed hulls, corncobs, and bagasse. Common nitrogen sources include wheat bran, cornmeal, and rice bran. Excessive or insufficient nitrogen can affect mycelial growth. Properly increasing nitrogen levels can promote mycelial growth, extend the vegetative growth cycle, and delay the transformation to fruiting bodies. Formula A produced the highest mycelial mat biomass, and its carbon-nitrogen ratio was optimal for mycelial growth.

[0067] Example 3:

[0068] The specific implementation method is the same as that of Example 1, except that the 1% potassium dihydrogen phosphate in step (3) is changed to 0.2%, 0.4%, 0.6%, 0.8%, 1.2%, 1.4%, 1.6%, 1.8%, and 2%. Leather is prepared according to Example 1.

[0069] The results show:

[0070] The mycelial carpet biomass in step (4) and the leather thickness in step (5) were tested. The results are shown in Table 2 below:

[0071] Table 2

[0072]

[0073] Phosphorus in mycelium mainly promotes glucose metabolism and the synthesis of nucleic acid substances. Mycelium requires the most phosphorus in the early stages of growth. Potassium does not participate in mycelial structure, but it affects the permeability of mycelial cell membranes, thereby affecting the mycelium's absorption of nutrients. Too low levels of these two elements will affect the normal metabolism of mycelium and be detrimental to mycelial growth, while too high levels will lead to over-nutrition and abnormal mycelial growth. When the concentration of potassium dihydrogen phosphate is 1%, the mycelial biomass is the highest (142.3g).

[0074] Example 4:

[0075] The specific implementation method is the same as that of Example 1, except that the 1% of calcium carbonate in step (3) is changed to 0.25%, 0.5%, 1.25%, and 1.5% respectively. Leather is prepared according to Example 1.

[0076] The results show:

[0077] The mycelial carpet biomass in step (4) and the leather thickness in step (5) were tested. The results are shown in Table 3 below:

[0078] Table 3

[0079] <![CDATA[CaCO3 concentration (%)]]> 0.25 0.5 1 1.25 1.5 Biomass (g) 113.2 132.5 142.3 139.6 132.8 Thickness (mm) 1.5 2.1 3 2.6 1.9

[0080] Calcium is a key component of the cell wall and regulates cellular osmotic pressure. Appropriate concentrations of calcium ions promote hyphal growth. Under the combined action of electric and magnetic fields, they induce upward mycelial growth and increase the thickness of the aerial mycelial layer. Excessively high or low concentrations are detrimental to mycelial growth. When calcium carbonate is present at 1%, the mycelial mat reaches its maximum concentration and thickness.

[0081] Example 5:

[0082] The specific implementation method is the same as Example 1, except that the temperature of 28°C in step (4) is changed to: 20°C, 22°C, 24°C, 26°C, 30°C, 32°C, and 34°C respectively.

[0083] The results show:

[0084] The mycelial carpet biomass in step (4) and the leather thickness in step (5) were tested. The results are shown in Table 4 below:

[0085] Table 4

[0086] Temperature (℃) 20 22 24 26 28 30 32 34 Biomass (g) 89.6 93.8 112.5 128.9 142.3 136.8 112.7 / Thickness (mm) 0.4 0.6 1.8 2.4 3 2.6 1.9 /

[0087] At low temperatures, mycelium grows densely but slowly. At high temperatures, mycelium respiration outweighs assimilation, nutrient consumption outstrips synthesis, leading to metabolic abnormalities and even death. Mycelial biomass and leather thickness reach their maximum at 28°C, making it the optimum temperature.

[0088] Example 6:

[0089] The specific implementation scheme is the same as Example 1, except that the humidity of 70% in step (4) is changed to 40%, 50%, 60%, 80%, 90%, and 100%.

[0090] The results show:

[0091] The mycelial carpet biomass in step (4) was detected, and the results are shown in Table 5 below:

[0092] Table 5

[0093] humidity(%) 40 50 60 70 80 90 100 Biomass (g) / 98.6 120.3 142.3 119.6 102.5 /

[0094] The moisture required for mycelium growth mainly comes from the matrix. When the humidity is 70%, it can ensure that the moisture in the matrix will not evaporate too quickly. When the humidity is too low, the mycelium is in a dormant state and stops growing. When the humidity is too high, the oxygen content will be reduced, causing the mycelium to suffocate and die.

[0095] Example 7:

[0096] The specific implementation scheme is the same as Example 1, except that the nitrogen concentration of 88% in step (4) is changed to: 78%, 80%, 82%, 84%, 86%, and 90% respectively.

[0097] The results show:

[0098] The mycelial carpet biomass in step (4) and the leather thickness in step (5) were tested. The results are shown in Table 6 below:

[0099] Table 6

[0100] Neon concentration (%) 78 80 82 84 86 88 90 Biomass (g) 101.3 112.3 125.8 130.9 135.8 142.3 96.3 Thickness (mm) 0.3 0.5 1.8 2.1 2.6 3 /

[0101] The density of nitrogen is lower than that of air, so it will automatically float on the top of the fermentation box, reducing the oxygen content inside the matrix and inducing the mycelium to grow towards places with higher oxygen content, that is, to grow downward, thereby increasing the thickness of the mycelium blanket. When the nitrogen concentration reaches 88%, the biomass and thickness of the mycelium blanket reach the maximum value. When the nitrogen concentration exceeds 88%, the oxygen concentration in the matrix is ​​too low, which will cause the mycelium to suffocate and die. Therefore, a nitrogen concentration of 88% is most suitable.

[0102] Example 8:

[0103] The specific implementation scheme is the same as Example 1, except that the electric field strength of 30 KV / m in step (4) is changed to: 10 KV / m, 50 KV / m, 70 KV / m, 90 KV / m respectively.

[0104] The results show:

[0105] The mycelial carpet biomass in step (4) and the leather thickness in step (5) were tested. The results are shown in Table 7 below:

[0106] Table 7

[0107] Electric field strength (KV / m) 10 30 50 70 90 Biomass (g) 122.6 142.3 140.6 136.5 129.4 Thickness (mm) 2.1 3 2.8 2.5 2.2

[0108] The electric field causes the positive ions in the mycelium to move downward, thereby inducing the mycelium to grow downward. When the electric field strength reaches 30KV / m, the biomass and leather thickness of the mycelium blanket reach the maximum. Excessively high electric field strength will inhibit the growth of the mycelium.

[0109] Example 9:

[0110] The specific implementation scheme is the same as Example 1, except that the magnetic field intensity of 50 mT in step (4) is changed to: 10 mT, 30 mT, 70 mT, and 90 mT respectively.

[0111] The results show:

[0112] The mycelial carpet biomass in step (4) and the leather thickness in step (5) were tested. The results are shown in Table 8 below:

[0113] Table 8

[0114]

[0115]

[0116] The magnetic field can increase the permeability of the cell membrane, facilitating the transport of nutrients between cells. When the magnetic field intensity increases, the biomass of the mycelial carpet also increases. When the magnetic field intensity reaches 50mT, the mycelial carpet biomass and leather thickness reach the maximum. If the magnetic field intensity continues to increase, the mycelial carpet biomass and leather thickness tend to be stable.

[0117] Comparative Example 1:

[0118] The exogenous nutrients in step (3) were omitted, and the rest were the same as in Example 1.

[0119] Comparative Example 2:

[0120] The red light (650 nm) irradiation in step (4) was omitted, and the culture was changed to dark conditions. The rest was consistent with Example 1.

[0121] Comparative Example 3:

[0122] The red light (650 nm) irradiation in step (4) was omitted, and the culture was performed under blue light (540 nm) irradiation instead. The rest of the steps were the same as those in Example 1.

[0123] Comparative Example 4:

[0124] Omit the red light (650nm) irradiation in step (4) and culture under green light (460nm) instead. The rest is the same as in Example 1.

[0125] Comparative Example 5:

[0126] The magnetic field in step (4) is omitted, and the rest remains the same as in Example 1.

[0127] Comparative Example 6:

[0128] The electric field in step (4) is omitted, and the rest remains the same as in Example 1.

[0129] Comparative Example 7:

[0130] The uniform spraying of the nutrient solution in step (4) was omitted, and the rest was consistent with Example 1.

[0131] Table 9

[0132] Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Biomass (g) 56.3 140.3 135.6 102.6 123.6 136.5 106.8 Thickness (mm) / 2.9 2.4 0.6 2.1 2.5 /

[0133] In Comparative Example 1, exogenous nutrients are omitted, and the biomass is very low. Phosphorus, potassium, calcium, etc. are important elements that make up mycelial cells. They are involved in energy transfer, maintaining the function of enzymes, etc. The lack of these important elements will have an adverse effect on the growth of mycelium. Comparative Examples 2, 3, and 4 show that red light is the most suitable light source. The mycelial biomass and leather thickness of Comparative Examples 5 and 6 are less than those of Example 2, indicating that the electric field and the magnetic field are more conducive to mycelial growth when they act together. In Comparative Example 7, the biomass is low and the mycelial blanket is seriously materialized, and leather cannot be made because when the nutrients in the matrix are exhausted, the mycelium will transform into fruiting bodies. Therefore, the immediate supplementation of nutrients can extend the nutritional growth cycle of the mycelium, thereby achieving the effect of increasing the biomass of the mycelial blanket.

[0134] Example 10: Preparation of mycelium fiber composite material

[0135] (1) Mycelium fiber composite

[0136] The viscose felt was soaked in the culture solution for more than 12 hours, taken out to dry, sterilized, and covered on the surface of the mushroom bag obtained in step (3) of Example 1 after cooling. It was wrapped with plastic wrap and pierced with holes on the surface to prevent rapid water loss. It was then placed in a 28°C incubator for substrate culture for 10 days. After 10 days, the mycelium covered the fiber blanket, and the fiber blanket was peeled off to obtain a mycelium fiber composite.

[0137] (2) Leather preparation

[0138] The mycelium fiber composite obtained in step (1) was naturally dried, then soaked in a 10% sodium bicarbonate solution for 8 hours, washed to remove excess alkali solution, and soaked in a tannic acid / glycerol solution for 24 hours. After soaking, the composite was taken out and dried, soaked in a 20% zein solution for 3 hours, taken out and dried, and hot-pressed at 80° C. for 2 minutes. The surface was evenly coated with a 5% shellac solution to obtain leather. The leather properties were tested.

[0139] The results are shown in the following table:

[0140] Table 10

[0141] Tensile strength (MPa) Elongation at break (%) Weight loss rate (%) Folding resistance (times) feel Example 1 13.2 79.6 90.5 4653 Soft and delicate Example 10 11.9 56.2 61.2 2789 Soft and fluffy Cowhide leather 15～30 10～50 50～80 / Soft and hard Sheepskin leather 7～20 20～50 70～90 / Soft and delicate

[0142] In Example 10, a fiber blanket was used as the skeleton, and mycelium was used as the adhesive to grow in close contact with the fibers. During the cultivation process, the mycelium decomposed and absorbed the fiber blanket. Moreover, due to the space occupied by the fibers, the mycelium did not grow densely enough, resulting in a less full feel and less strength than in Example 1. The addition of the fiber blanket reduced the weight loss rate and the folding resistance.

[0143] The tensile strength of Example 1 is comparable to that of animal leather, but its elongation at break is better than that of animal leather, making it more elastic. In terms of weight loss rate, animal leather is less susceptible to rot due to tanning, resulting in a slower degradation rate. Cowhide leather is generally tougher and harder, with a certain degree of elasticity and firmness. Although it may be relatively rough or granular, it can become softer after processing. In contrast, sheepskin is softer and more delicate, and its surface is usually smooth. It feels more comfortable and is less likely to feel hard or rough. The feel of Example 1 is similar to that of sheepskin, but the feel of other types of leather can also be simulated through different processing methods.

[0144] Although the present invention has been disclosed above in terms of preferred embodiments, it is not intended to limit the present invention. Anyone familiar with this technology may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. A method for preparing pure mycelium leather by solid-state fermentation, characterized in that: The method comprises the following steps: (1) Activation of bacteria Activating the fungi using a culture medium, wherein the fungi are fungi, including Ganoderma lucidum, Pleurotus ostreatus, Lentinus edodes, Volvariella volvacea, Pleurotus ostreatus, Enoki mushroom, Hericium erinaceus, Pleurotus eryngii, Agaricus bisporus, Auricularia auricularia, Tremella fuciformis, Chanterelles, Morchella edodes, Botrytis cinerea, Dictyophora indica, and Schizophyllum gracile; (2) Preparation of bacterial strains Wrap the wet wood strips with bran and flour, sterilize and cool them for later use, inoculate the pure strain activated in step (1) onto the wood strips, and culture them at 28°C for 8 to 10 days until the wood strips are covered with mycelium; (3) Preparation of bacterial bags The exogenous nutrients are mixed evenly with the solid culture medium, and the mixture is divided into fermentation bags, sterilized and cooled, and the wood strips covered with mycelium obtained in step (2) are inserted into the fermentation bags, and cultured at 28° C. for 8 to 10 days until the mycelium fills the fermentation bags, thereby obtaining bacterial bags; the solid culture medium formula is: 40% corn cobs, 20% bran, 20% sawdust, 20% flour, and 70% water content; the addition amounts of the exogenous nutrients are: 1% potassium dihydrogen phosphate, 1% calcium carbonate, 10% glucose, and 1% magnesium sulfate; (4) Preparation of mycelium blanket: The fungus bag obtained in step (3) was broken up and spread flat on the iron mesh on the top of the fermentation box, and static culture was started. During this period, the external conditions were controlled so that the aerial hyphae grew downward through the iron mesh and entangled with each other to completely cover the surface of the solid culture medium. After static culture for 7 days, the nutrient solution was sprayed, and the surface mycelium blanket was harvested after continuing static culture for 3 days; The external conditions include: temperature 28°C, humidity 70%, nitrogen concentration 88%, 650nm red light irradiation, electric field strength 30KV / m, and magnetic field strength 50mT; The nutrient solution formula is: 10g / L soluble starch, 1.5g / L soy peptone, 20g / L glucose, 0.75g / L potassium dihydrogen phosphate, 1.5g / L magnesium sulfate, and 0.1g / L vitamin B1; (5) Preparation of mycelium vegan leather: The mycelium blanket obtained in step (4) is subjected to hot pressing, alkali treatment, cross-linking, plasticization and coating to obtain mycelium vegan leather.

2. The method for preparing pure mycelium leather by solid-state fermentation according to claim 1, characterized in that: The activation step of the bacterial strain in step (1) is as follows: 2 The fungus was inoculated on PDA medium and cultured at 28℃ for 4 days. 1 cm 2 The tip hyphae were inoculated on new PDA medium and cultured for 4 days, and repeated three times to obtain pure strains.

3. The method for preparing pure mycelium leather by solid-state fermentation according to claim 1, characterized in that: The hot pressing shaping in step (5) is as follows: hot pressing at a temperature of 80° C. and a pressure of 1 MPa for 1 minute.

4. The method for preparing pure mycelium leather by solid-state fermentation according to claim 1, characterized in that: The alkali treatment in step (5) refers to soaking in a sodium hydroxide aqueous solution with a mass fraction of 5 to 10% for 12 hours.

5. Pure mycelium leather prepared according to the method according to any one of claims 1 to 4.

6. A method for preparing a mycelium fiber composite material, characterized in that: It includes the following steps: (1) Mycelium fiber composite Prepare the bacterial bag according to steps (1) to (3) of claim 1; The fiber blanket is soaked in the culture solution for more than 12 hours, taken out to dry, sterilized, and covered on the surface of the fungus bag after cooling. It is wrapped with plastic wrap and pierced on the surface to prevent rapid water loss. It is then placed in a 28°C incubator for 10 days. After 10 days, the mycelium will cover the fiber blanket. The fiber blanket is peeled off to obtain a mycelium-fiber composite. The fiber blanket includes but is not limited to blankets woven using cotton fiber, hemp fiber, polyester fiber, regenerated cellulose fiber, and wool fiber; The culture medium is 10 g / L soluble starch, 1.5 g / L soy peptone, 20 g / L glucose, 0.75 g / L potassium dihydrogen phosphate, 1.5 g / L magnesium sulfate, and 0.1 g / L vitamin B1; (2) Preparation of mycelium fiber composite materials The mycelium fiber composite obtained in step (1) is cross-linked, plasticized, filled, hot-pressed, and coated to obtain a mycelium fiber composite material.

7. The mycelium fiber composite material prepared by the method according to claim 6.

8. A method for secondary utilization of waste solid culture medium, characterized in that: The discarded solid culture medium is crushed and pressed into a mold, and cultured at 28 degrees Celsius for 3 to 5 days. After the culture is completed, the mold is removed and the mycelium material is placed in an oven and dried at 50 to 100 degrees Celsius to obtain a mycelium buffer material; The discarded solid culture medium is the discarded substrate remaining after harvesting the surface mycelium carpet in step (4) of claim 1.

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