Pure edible mushroom mycelium fiber material, and preparation method and application thereof

Abstract

This invention discloses a pure edible fungus mycelial fiber material, its preparation method, and its applications. The preparation method includes the following steps: S1, fungal activation; S2, liquid static film formation; S3, semi-solid thickening; S4, solid cultivation and environmental induction for densification and solidification: the thickened mycelial layer is peeled off and transferred to a solid cultivation environment containing a support carrier, inducing the mycelium to densify and solidify, obtaining a pure mycelial fiber dense layer; S5, peeling and post-treatment; S6, hot pressing to obtain the pure edible fungus mycelial fiber material. This invention completely eliminates the limitations of agricultural waste substrates on material performance. The obtained pure mycelial material has a complete mycelial skin morphology, high density, and certain tensile strength, and can be used to prepare imitation leather materials, decorative finishes, etc., possessing high application value.

Description

Technical Field

[0001] This invention belongs to the field of bio-based polymer materials and fungal biotechnology, and particularly relates to a pure edible fungal mycelial fiber material, its preparation method and application. Background Technology

[0002] Mycelium-based biomaterials, with edible fungi mycelium as the core component, have advantages such as being naturally biodegradable, biocompatible, having renewable raw materials, and being low-carbon and environmentally friendly in the production process. They are an ideal alternative to traditional petroleum-based plastics and leather, and show broad application prospects in clothing, footwear, bag manufacturing, and biomedical fields.

[0003] Most existing mycelial composite materials use mycelium as a "binder" to grow on agricultural waste substrates (such as straw and sawdust). While this "mycelium + substrate" model utilizes waste, it has significant drawbacks:

[0004] Firstly, the performance is limited by the substrate: the mechanical properties, uniformity, and durability of the material largely depend on the loose and porous agricultural waste particles, resulting in low product density, large strength fluctuations, and easy moisture absorption and rotting. Secondly, it is difficult to efficiently prepare pure mycelium materials: At present, there is a lack of efficient and low-cost methods to prepare large-area, thick-sized "pure mycelium" materials. Traditional liquid deep fermentation can only produce mycelium ball suspensions, which are difficult to form continuous membranes. If solid culture is not added to the substrate, the mycelium often grows sparsely and loosely, and cannot support itself.

[0005] Third, densification is difficult: pure mycelium is fluffy and cottony in its natural growth state with extremely high porosity. Direct hot pressing will lead to severe rebound and delamination, making it difficult to form dense fiberboard.

[0006] Therefore, developing a technology that can detach from agricultural waste substrates, and through specific cultivation strategies and environmental control, enable mycelium to grow into a dense, thick, and high-strength pure mycelial fiber layer, and achieve industrial-scale molding, is the key to breaking through the bottleneck of mycelial material application. Summary of the Invention

[0007] The edible fungi mycelial fiber material, its preparation method, and its application proposed in this invention utilize a unique "membrane-transfer" multi-stage cultivation route. First, a seed membrane is constructed on the liquid surface, then thickened in a semi-solid medium. Finally, under solid cultivation conditions, a four-dimensional environmental control technology of "temperature, light, gas, and humidity" is used to induce biological densification and solidification of the mycelium, resulting in the peeling off of an independent pure mycelial fiber layer. This layer is then hot-pressed into a high-performance biological mycelial skin material with high density and a certain tensile strength.

[0008] This invention proposes a method for preparing pure edible fungi mycelial fiber material, comprising the following steps: S1. Activation of microbial strains: Edible fungi strains are inoculated into suitable PDA medium and activated under dark conditions to obtain activated microbial strains; S2. Liquid static film formation: The above-mentioned activated bacterial strains are inoculated into a suitable liquid culture medium and statically cultured in the dark to form an initial mycelial film at the liquid-gas interface. S3, Semi-solid thickening: The initial mycelial membrane is peeled off and transferred to the surface of a semi-solid culture medium for culture, resulting in a thickened mycelial layer; S4. Solid cultivation and environmental induction for densification and solidification: The thickened mycelial layer is peeled off and transferred to a solid cultivation environment containing a support carrier. By comprehensively controlling the temperature, light, gas composition and humidity, the mycelium is induced to densify and solidify itself to obtain a pure mycelial fiber dense layer. S5. Peeling and post-treatment: Peel the above-mentioned dense layer of pure mycelial fibers from the support carrier, inactivate it first, and then dry it to a moisture content of 7.5-8.0% to obtain a dry pure mycelial fiber layer. S6. Hot pressing molding: The above-mentioned dried pure mycelium fiber layer is molded to obtain pure edible fungus mycelium fiber material.

[0009] Furthermore, edible fungi include at least one of oyster mushrooms and reishi mushrooms; and / or The activation culture temperature is 24~26℃; the activation culture time is 6~10 days.

[0010] Furthermore, in S1, the edible fungus is oyster mushroom; the oyster mushroom strain is a eurythermal oyster mushroom strain; The PDA medium suitable for the oyster mushroom strain is a basic PDA medium; the basic PDA medium consists of: 200 g / L potato starch, 20 g / L glucose, 18-20 g / L agar, and distilled water to a final volume of 1000 mL, with a pH of 6.0-6.5; and / or In S1, the edible fungus is Ganoderma lucidum; The PDA medium suitable for Ganoderma lucidum strains is an optimized PDA medium; the optimized PDA medium consists of: 200 g / L potato, 25 g / L glucose, 18-20 g / L agar, and distilled water to a final volume of 1000 mL, with the pH adjusted to 5.8±0.1.

[0011] Furthermore, in S2, the static culture temperature is 24–26°C; the static culture time is 20–30 days; and / or In S2, the suitable liquid culture medium composition for activated oyster mushroom spawn is: glucose 50.0±0.5 g / L, peptone 2.0±0.1 g / L, yeast extract 1.0±0.05 g / L, distilled water to a final volume of 1000 mL, and pH adjusted to 6.2±0.1; and / or In S2, the liquid culture medium suitable for activated Ganoderma lucidum strains consists of: glucose 55.0±0.5 g / L, peptone 2.5±0.1 g / L, yeast extract 1.5±0.05 g / L, potassium dihydrogen phosphate 1.0 g / L, magnesium sulfate 0.5 g / L, and distilled water to a final volume of 1000 mL, with the pH adjusted to 6.8±0.1.

[0012] Furthermore, in S3, the incubation time on the surface of the semi-solid culture medium is 7-14 days, and / or In S3, the semi-solid culture medium is based on the liquid culture medium described in S2, with the addition of a coagulant with a mass fraction of 0.2%-0.8%. Preferably, the coagulant includes at least one of agar, carrageenan, gellan gum, or sodium alginate.

[0013] Furthermore, in S4, the solid-state cultivation environment includes temperature, light, gas composition, and humidity; The temperature ranges from 28 to 31°C. Humidity: Relative humidity 80~90%; Illumination: In dark conditions, use blue light irradiation or a combination of blue light and low-dose UV-A irradiation; Gas: The incubator is sealed and uses a sterile mixed gas, which is introduced into the incubator through sterile tubing. The number of gas exchanges is controlled to be once every 8 to 10 hours, and the time for each gas exchange is 25 to 35 seconds.

[0014] Furthermore, the darkness conditions consist of shading the incubator from light, with a light intensity ≤5 Lux; and / or The specific method of using blue light irradiation is as follows: starting from day 1 of cultivation, turn on the blue LED light, maintain a stable light intensity of 280~340 Lux, and provide continuous 24-hour illumination without interruption; and / or The specific method of using low-dose UV-A irradiation is as follows: turn on the UV-A ultraviolet lamp, irradiate with low dose, control the irradiation intensity at 40~60 μW / cm², and irradiate for 2 hours per day.

[0015] Furthermore, in S4, the solid culture environment contains a support carrier; Preferably, the support carrier is a combination of a stainless steel porous mesh plate and sterile moistened filter paper.

[0016] More preferably, the stainless steel porous mesh plate has a pore size of 0.3~0.6 mm, the sterile moistened filter paper has a basis weight of 120 g / m², and the wettability is 60~68% of the filter paper's saturated moisture content; and / or In S5, the inactivation temperature is 85-90℃; the inactivation time is 2-2.5 hours; the drying temperature is 60-65℃; and / or S6 also includes demolding after compression molding, holding pressure, and naturally cooling to room temperature; Preferably, the molding temperature is 160-175℃; the molding pressure is 15-20 MPa; and the holding time is 10-12 minutes.

[0017] The present invention also proposes pure edible fungi mycelial fiber materials prepared by any of the above-described preparation methods.

[0018] This invention also proposes the application of any of the above-mentioned pure edible fungi mycelial fiber materials in the preparation of imitation leather materials and decorative finishing materials.

[0019] This invention has the following advantages: The method for preparing pure edible fungi mycelial fiber material proposed in this invention employs a three-stage film-forming process: liquid static film formation, semi-solid culture for gradual thickening, and solid cultivation combined with environmental induction to further densify and solidify the thickened film. This process achieves precise control over the mycelial morphology from film to layer to dense body. During solid cultivation and environmental induction, a unique four-dimensional regulation of "temperature, light, gas, and humidity" is used, leveraging the fungi's own biological response mechanism to achieve self-densification during growth. This avoids the energy consumption and pollution associated with traditional chemical cross-linking or high-intensity mechanical compression, effectively improving the density of the pure edible fungi mycelial fiber material. This method completely eliminates the limitations imposed on material performance by agricultural waste substrates. The resulting pure mycelial material exhibits a complete mycelial skin layer morphology, high density, certain tensile strength, and biodegradability, making it suitable for preparing imitation leather materials, decorative finishes, etc., and possessing high application value. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of the oyster mushroom mycelial fiber material obtained in Example 1 of the present invention; Figure 2This is a schematic diagram of the structure of the oyster mushroom mycelial fiber material obtained in Comparative Example 1 of the present invention; Figure 3 This is a schematic diagram of the structure of the Ganoderma lucidum mycelium fiber material obtained in Example 2 of the present invention. Detailed Implementation

[0022] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0023] This invention provides a method for preparing pure edible fungi mycelial fiber material, comprising the following steps: S1. Activation of strains: Edible fungi strains are inoculated into suitable PDA medium (Potato Dextrose Agar medium) and activated under dark conditions to obtain activated strains; S2. Liquid static film formation: The above-mentioned activated bacterial strains are inoculated into a suitable liquid culture medium and statically cultured in the dark to form an initial mycelial film at the liquid-gas interface. S3, Semi-solid thickening: The initial mycelial membrane is peeled off and transferred to the surface of a semi-solid culture medium for culture, resulting in a thickened mycelial layer; S4. Solid cultivation and environmental induction for densification and solidification: The thickened mycelial layer is peeled off and transferred to a solid cultivation environment containing a support carrier. By comprehensively controlling the temperature, light, gas composition and humidity, the mycelium is induced to densify and solidify itself to obtain a pure mycelial fiber dense layer. S5. Peeling and post-treatment: Peel the above-mentioned dense layer of pure mycelial fibers from the support carrier, inactivate it first, and then dry it to a moisture content of 7.5-8.0% to obtain a dry pure mycelial fiber layer. S6. Hot pressing molding: The above-mentioned dried pure mycelium fiber layer is molded to obtain pure edible fungus mycelium fiber material.

[0024] In one embodiment of the present invention, in S1, the edible fungi include at least one of oyster mushroom and Ganoderma lucidum.

[0025] In one embodiment of the present invention, in S1, the activation culture temperature is 24~26℃, and the activation culture time is 6~10 days.

[0026] In one embodiment of the present invention, in S1, the edible fungus is *Pleurotus ostreatus*. The *Pleurotus ostreatus* strain is a eurythermal type. After activation and culture, the *Pleurotus ostreatus* mycelium is dense and white.

[0027] In one embodiment of the present invention, in S1, the PDA medium suitable for the oyster mushroom strain is the basic PDA medium; the basic PDA medium consists of: 200 g / L potato, 20 g / L glucose, 18-20 g / L agar, and distilled water to a final volume of 1000 mL, with a natural pH (6.0-6.5). The medium is sterilized by autoclaving at 121°C and 0.1 MPa for 20 min before use.

[0028] In one embodiment of the present invention, in S1, the edible fungus is Ganoderma lucidum. After activation and culture, the mycelium is white and dense, with no abnormal pigment secretion.

[0029] In one embodiment of the present invention, in S1, the PDA medium suitable for the Ganoderma lucidum strain is an optimized PDA medium; the optimized PDA medium consists of: 200 g / L potato, 25 g / L glucose, 18-20 g / L agar, and distilled water to a final volume of 1000 mL, with the pH adjusted to 5.8±0.1. The medium is sterilized by autoclaving at 121℃ and 0.1 MPa for 20 min before use.

[0030] In one embodiment of the present invention, in step S2, the static culture temperature is 24~26℃, and the static culture time is 20~30 days.

[0031] In one embodiment of the present invention, in S2, the liquid culture medium suitable for the activated oyster mushroom strain has the following composition: glucose 50.0±0.5 g / L, peptone 2.0±0.1 g / L, yeast extract 1.0±0.05 g / L, and distilled water to a final volume of 1000 mL, with the pH adjusted to 6.2±0.1. The culture medium is then sterilized by autoclaving at 121°C and 0.1 MPa for 20 min before use.

[0032] In one embodiment of the present invention, in S2, the activated oyster mushroom spawn, after static culture, forms a white initial mycelial membrane with a thickness of 5-10 mm.

[0033] In one embodiment of the present invention, in S2, the liquid culture medium suitable for the activated Ganoderma lucidum strain has the following composition: glucose 55.0±0.5 g / L, peptone 2.5±0.1 g / L, yeast extract 1.5±0.05 g / L, potassium dihydrogen phosphate 1.0 g / L, magnesium sulfate 0.5 g / L, and distilled water to a final volume of 1000 mL, with the pH adjusted to 6.8±0.1. The culture medium is then sterilized by autoclaving at 121℃ and 0.1 MPa for 20 min before use.

[0034] In one embodiment of the present invention, in S2, the activated Ganoderma lucidum strain, after static culture, forms a white initial mycelial membrane with a thickness of 4-6 mm.

[0035] In one embodiment of the present invention, in S3, the culture time on the surface of the semi-solid culture medium is 7-14 days.

[0036] In one embodiment of the present invention, in S3, the semi-solid culture medium is based on the liquid culture medium described in S2, with the addition of a coagulant having a mass fraction of 0.2%-0.8%.

[0037] Preferably, in S3, the coagulant includes at least one of agar, carrageenan, gellan gum, or sodium alginate.

[0038] Specifically, in S3, the method for preparing the semi-solid culture medium includes: adding carrageenan to the liquid culture medium, heating and stirring until the coagulant is completely dissolved, adjusting the pH to 6.2, sterilizing with high-pressure steam at 121°C and 0.1 MPa for 20 min, cooling to 45°C, pouring into a sterile shallow dish, and cooling and solidifying to form a semi-solid culture medium.

[0039] For example, in S3, the coagulant is carrageenan. The carrageenan addition amount suitable for the oyster mushroom strain is 0.4±0.02%, the thickness of the semi-solid culture medium after cooling and solidification is 1.5±0.1 cm, and the mycelial layer thickness reaches 15±0.2 mm after cultivation. The carrageenan addition amount suitable for the Ganoderma lucidum strain is 0.45±0.02%, the thickness of the semi-solid culture medium after cooling and solidification is 1.5±0.1 cm, and the mycelial layer thickness reaches 10±0.2 mm after cultivation.

[0040] In one embodiment of the present invention, in S4, the solid cultivation environment includes temperature, light, gas composition, and humidity; The temperature ranges from 28 to 31°C. Humidity: Relative humidity 80~90%; Illumination: In dark conditions, use blue light irradiation or a combination of blue light and low-dose UV-A irradiation; Gas: The incubator is sealed and uses a sterile mixed gas, which is introduced into the incubator through sterile tubing. The number of gas exchanges is controlled to be once every 8 to 10 hours, and the time for each gas exchange is 25 to 35 seconds.

[0041] In this embodiment of the invention, by comprehensively controlling the temperature, light, gas composition and humidity in the solid culture environment, the mycelium itself is induced to densify and solidify, resulting in a dense layer of pure mycelial fibers.

[0042] In a preferred embodiment of the present invention, the darkness condition is achieved by shading the incubator and the light intensity is ≤5 Lux.

[0043] In one embodiment of the present invention, the use of blue light irradiation specifically involves: starting from the first day of cultivation, turning on the blue LED lamp, with the light intensity remaining stable at 280~340 Lux, and providing continuous irradiation for 24 hours without interruption.

[0044] Preferably, the wavelength of the blue LED light is 400-500nm. The blue LED light is 20 cm away from the surface of the mycelial layer.

[0045] In a preferred embodiment of the present invention, the use of low-dose UV-A irradiation specifically involves: turning on the UV-A ultraviolet lamp, irradiating with a low dose, controlling the irradiation intensity to be 40~60 μW / cm², and irradiation time to be 2 hours per day.

[0046] Preferably, the 2 hours of irradiation per day is specifically divided into two irradiations, each lasting 1 hour, at 10:00-11:00 and 16:00-17:00 respectively.

[0047] Preferably, the wavelength of the UV-A ultraviolet lamp is 320-400 nm. The UV-A ultraviolet lamp is 30 cm away from the surface of the mycelial layer.

[0048] Preferably, the sterile gas mixture comprises 3-6% CO2, 19-22% O2, and the remainder nitrogen. This maintains a stable gas concentration within the incubator, limits oxygen supply, promotes dense horizontal mycelial interweaving, and enhances the overall rigidity of the material.

[0049] In one embodiment of the present invention, in step S4, the solid cultivation environment contains a support carrier. The content of the support carrier is trace, used only to support the growth of mycelial fibers, ultimately yielding pure mycelial material with a product purity >90%.

[0050] Preferably, the support carrier is a combination of a stainless steel porous mesh plate and sterile moistened filter paper.

[0051] More preferably, the stainless steel porous mesh plate has a pore size of 0.3~0.6 mm, the sterile moistened filter paper has a basis weight of 120 g / m², and the wettability is 60~68% of the saturated water content of the filter paper.

[0052] In one embodiment of the present invention, in step S5, the inactivation temperature is 85-90°C; the inactivation time is 2-2.5 hours. The drying temperature is 60-65°C.

[0053] In one embodiment of the present invention, S6 further includes, after compression molding, holding pressure, and naturally cooling to room temperature before demolding.

[0054] In one embodiment of the present invention, in step S6, the molding temperature is 160-175°C; the molding pressure is 15-20 MPa.

[0055] In one embodiment of the present invention, in step S6, the pressure holding time is 10-12 minutes.

[0056] In this embodiment of the invention, all steps S1-S6 are carried out in a sterile environment to avoid contamination by miscellaneous bacteria, and no granular agricultural by-products such as straw, sawdust, and rice husks are added throughout the process.

[0057] On the other hand, embodiments of the present invention also propose pure edible fungi mycelial fiber materials prepared by any of the preparation methods described above.

[0058] Preferably, the pure edible fungus mycelium fiber material is composed of more than 90% by weight of edible fungus mycelium and does not contain macroscopically visible agricultural waste particles; The density of pure edible fungi mycelial fiber material is 0.6-1.2 g / cm³, and the tensile strength is ≥5 MPa.

[0059] The pure edible fungus mycelium fiber material obtained in the embodiments of the present invention has a highly dense and interwoven internal mycelium network and high tensile strength.

[0060] In another aspect, embodiments of the present invention also propose the application of any of the above-described pure edible fungi mycelial fiber materials in the preparation of imitation leather materials and decorative finishing materials.

[0061] The present invention will now be described in detail with reference to the embodiments.

[0062] Example 1 A method for preparing high-density pure oyster mushroom mycelium material includes: (1) Activation of microbial strains Select oyster mushrooms ( Pleurotus ostreatus Wide-temperature strain; PDA slant culture medium formula: 200 g / L potato (peeled, diced, boiled for 30 min, filtered), 20 g / L glucose, 18-20 g / L agar, distilled water to a final volume of 1000 mL, pH natural (6.0-6.5), autoclaved at 121℃ and 0.1 MPa for 20 min, cooled to approximately 45℃ and poured into plates. Using a sterile punch, 2 mm diameter holes were punched in the oyster mushroom spawn stored at 4℃. These spawn blocks were then inoculated onto the center of a PDA plate and placed in a constant temperature incubator at 25±0.5℃ in the dark for 7 days until the mycelium completely covered the slant, exhibiting dense, white mycelium free of contamination.

[0063] (2) Liquid static film formation Culture medium formulation: 50.0 g / L glucose, 2.0 g / L peptone, 1.0 g / L yeast extract, distilled water to a final volume of 1000 mL, pH adjusted to 6.2, autoclaved at 121℃ and 0.1 MPa for 20 min, then cooled to 25℃ for use.

[0064] Operating details: Select a sterile shallow dish (size: Φ10 cm × 5 cm), pour the cooled culture medium into the shallow dish, control the liquid depth to 1.5 cm, and the volume of each dish of culture medium is about 20 mL; aseptically pick 3-4 activated inoculum blocks with a diameter of 3 mm (all taken from the dense part of the mycelium on the plate), and inoculate them evenly on the liquid surface (5 cm apart), place them in a constant temperature incubator, and incubate statically in the dark at 25±0.5℃ for 20-30 days (the mycelium grows against the wall for the first 3 days, scattered mycelial spots appear on the liquid surface on the 5th day, and the mycelial spots merge on the 7th-14th day to form a complete, continuous white mycelial membrane with a thickness of 0.3-0.5 mm. The mycelial membrane is undamaged, without air bubbles, and has good toughness. On the 15th-30th day, the mycelial membrane thickens to 5-10 mm).

[0065] (3) Semi-solid thickening Culture medium formulation: Use the same formulation as the liquid static film-forming culture medium, add 0.4% carrageenan (food grade, viscosity 1000-1200 mPa·s), heat to 95℃ and stir for 30 min until the carrageenan is completely dissolved, adjust the pH to 6.2, autoclave at 121℃ and 0.1 MPa for 20 min, cool to about 45℃, pour into a sterile shallow dish (same as the liquid film-forming shallow dish), and after cooling and solidification, form a semi-solid gel (gel thickness 1.5±0.1 cm, uniform texture, no lumps).

[0066] Operating details: In a sterile laminar flow hood, gently lift the intact mycelial membrane after liquid culture with sterile tweezers (avoiding damage), and lay it flat on the surface of the semi-solid gel, ensuring that the mycelial membrane and gel are completely adhered, without air bubbles or wrinkles; place the shallow dish in a constant temperature incubator and incubate at 25±0.5℃ in the dark for 7-14 days, observing the mycelial growth daily. After the culture is completed, the mycelial layer absorbs nutrients from the gel, thickens to 15 mm, and becomes a dense, felt-like substance that is soft and elastic to the touch, leaving no residue after separation from the gel.

[0067] (4) Solid cultivation and environmental induction to solidify Transfer procedure: Select a stainless steel perforated mesh plate (0.5 mm aperture, uniform mesh distribution, pre-sterilized). Lay a layer of sterile filter paper (120 g / m²) flat under the mesh plate. Spray the filter paper with sterile deionized water to moisten it (the moisture content should be controlled to 60% of the filter paper's saturated water content, i.e., the filter paper should not drip water and should feel moist to the touch), ensuring that there are no solid particles (to avoid introducing impurities and ensure the pure mycelial characteristics). Use sterile tweezers to gently peel off the 15 mm thick semi-solid thickened mycelial layer and lay it flat on the perforated mesh plate. The mycelial layer should be laid flat, without overlap or damage. Place the mesh plate in a sterile incubator.

[0068] Four-dimensional regulation (total duration 10 days, phased and precise control): a. Temperature: The temperature was controlled at 29±0.5℃ throughout the process, under dark conditions (the incubator was shaded, and the light intensity was ≤5 Lux) to avoid temperature fluctuations affecting mycelial densification; b. Illumination: Starting from the first day of cultivation, turn on the 460±10 nm blue LED lamp (20 cm away from the surface of the mycelium layer), and keep the light intensity stable at 300±20 Lux for 24 hours without interruption (blue light induces the thickening of the mycelial cell wall and promotes the dense interweaving of mycelia). c. Gas: The incubator is sealed and a sterile mixed gas (containing 5.0±0.5% CO2, 21±0.5% O2, and the remainder being nitrogen) is introduced into the incubator through sterile tubing. The number of gas exchanges is controlled to be once every 8 hours, with each gas exchange lasting 30 seconds. This maintains a stable gas concentration in the incubator, limits the oxygen supply, and promotes the horizontal interweaving of mycelia. d. Humidity: The relative humidity inside the incubator is controlled at 85±5% throughout the process (using a sterile humidifier, monitored 3 times a day at 8:00, 14:00 and 20:00) to avoid contamination by miscellaneous bacteria due to excessive humidity and dryness and cracking of mycelium due to excessive humidity.

[0069] After the regulation was completed, the mycelial layer became significantly denser, with a thickness of about 8 mm. It was tough, without any looseness or adhesion.

[0070] (5) Stripping and post-processing Peeling procedure: Gently peel off the complete pure mycelial layer from the mesh plate using sterile tweezers (at this point, the mycelial layer is not adhered to the mesh plate or filter paper and can be peeled off completely without any damage to the edges); Spread the peeled mycelial layer flat on a baking tray and place it in a constant temperature oven. First, inactivate it at 85±1℃ for 2 hours (to completely kill the mycelial activity and prevent subsequent mold growth), then adjust the oven temperature to 60±1℃ and continue drying until the moisture content of the mycelial layer is 8.0±0.5% (turn it over once every 2 hours during the drying process to ensure uniform drying; the moisture content is measured using a moisture analyzer; 3 samples are tested for each batch, and the average value is taken); After drying, the mycelial layer becomes hard and its thickness becomes 3.0±0.1 mm.

[0071] (6) Hot pressing Equipment: Flat plate hot press (pressure accuracy ±0.5 MPa, temperature accuracy ±1℃); the hot press mold is a smooth stainless steel mold (size: 30 cm × 20 cm), and the mold surface is wiped clean.

[0072] Hot pressing conditions: Preheat the mold to 160±1℃, spread the dried mycelium layer evenly in the center of the mold, place it flat, apply pressure of 15±0.5 MPa, hold the pressure for 10 minutes, and expel the air in the mold during the hot pressing process (to avoid air bubbles in the finished product); after the hot pressing is completed, let it cool naturally to room temperature (about 25℃) before demolding.

[0073] Finished product specifications: A pure oyster mushroom mycelium skin layer, 1-2 mm thick, resembling imitation leather, with an off-white appearance and a natural mycelial interweaving texture on the surface (clear texture, no obvious defects); tested to have a tensile strength of 5 MPa, an elongation at break of 10±1%, a moisture content of 8.0±0.5%, and no off-odors or contaminating bacteria. See product details below. Figure 1 .

[0074] Comparative Example 1 Similar to Example 1, the difference lies in the solid cultivation stage. A small amount (0.5-1 cm high) of solid granular material (80% sawdust, 20% wheat bran, mixed and sterilized at 121°C and 0.1 MPa for 60 min) is added below the stainless steel perforated mesh plate and evenly spread on moist filter paper. The remaining four-dimensional control parameters are completely consistent with Example 1. See the image of the resulting product. Figure 2 .

[0075] Experimental Example 1 The materials obtained in Example 1 and Comparative Example 1 were subjected to performance tests.

[0076] (1) Stability of solid culture process Direct observation method: Visually record the growth status of the mycelial layer, whether it is uniform, whether there is contamination by other bacteria, whether there is local caking / mold, and count any abnormalities during the growth cycle.

[0077] (2) Mycelial adhesion Peeling test: The mycelial layer is manually peeled off from the support carrier, and the ease of separation, damage, and adhesion to the carrier / itself are recorded. The ability to peel off completely is the evaluation criterion.

[0078] (3) Mycelial purity Visually inspect whether the texture is uniform, and examine under a microscope for any solid particle impurities; verify the impurity content through physical sieving and density separation.

[0079] (4) Subsequent hot pressing effect Appearance evaluation method: After hot pressing, visually inspect the surface of the finished product to see if it is smooth, whether there are bubbles / hard lumps / particle protrusions, and whether the texture is uniform, and compare the appearance of the finished product.

[0080] (5) Density Density testing (mass / volume, g / cm³) is used to characterize the degree of compactness. The mass m of the specimen is weighed using an electronic balance (accuracy 0.001 g); the length and width of the specimen are measured using digital vernier calipers, and the cross-sectional area S is calculated; the original thickness T of the specimen is measured. The density is calculated using the following formula: ρ=m / (S×T)×10 3 In the formula: ρ is the density of the specimen (g / cm³); m is the mass of the specimen (g); S is the cross-sectional area of ​​the specimen (mm²); T is the original thickness of the specimen (mm).

[0081] (6) Product mechanical properties Universal testing machine: According to GB / T 528–2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber", test mechanical properties such as tensile strength and elongation at break.

[0082] (7) Success rate of preparation Batch statistics method: Multiple batches are prepared continuously, and the proportion of successful batches to total batches is counted (success rate = successful batches / total batches × 100%), while recording the differences between batches.

[0083] The test results are shown in Table 1 below.

[0084] Table 1

[0085] Example 2 Pure Ganoderma lucidum mycelium hard fiber material (1) Activation of microbial strains Select Ganoderma lucidum ( Ganoderma lucidum The strain was prepared using the following PDA medium: 200 g / L potato (peeled, diced, boiled for 35 min, filtered to remove impurities and avoid affecting mycelial purity), 25 g / L glucose, 18-20 g / L agar, and distilled water to a final volume of 1000 mL. The pH was adjusted to 5.8 (to suit the growth preference of Ganoderma lucidum mycelia). The medium was then autoclaved at 121℃ and 0.1 MPa for 20 min, cooled to 42℃, and poured into plates. A 2 mm diameter piece of Ganoderma lucidum spore (selecting a dense, bacteria-free section) was inoculated onto the center of a PDA slant from a 4℃ refrigerator. The plate was then placed in a constant temperature incubator at 26±0.5℃ in the dark for 8 days until the mycelia completely covered the slant, exhibiting white, dense, and resilient mycelia, free from contamination and abnormal pigment secretion.

[0086] (2) Liquid static film formation Culture medium formulation: 55.0 g / L glucose, 2.5 g / L peptone, 1.5 g / L yeast extract, 1.0 g / L potassium dihydrogen phosphate, 0.5 g / L magnesium sulfate, and distilled water to a final volume of 1000 mL. Adjust the pH to 6, autoclave at 121℃ and 0.1 MPa for 20 min, and cool to 26℃ for later use (avoid excessively high temperatures that could damage the bacterial activity).

[0087] Operating details: Select a sterile shallow dish (size: 32 cm × 20 cm × 5 cm), pour the cooled culture medium into the shallow dish, control the liquid depth to 1.5 cm, and the volume of each dish of culture medium is about 100 mL; aseptically pick 5-6 activated inoculum blocks with a diameter of 3 mm (all taken from the dense part of the mycelium on the plate), and inoculate them evenly on the liquid surface (5 cm apart), place them in a constant temperature incubator, and incubate statically in the dark at 25±0.5℃ for 20-30 days (for the first 4 days, the mycelium adheres to the wall and grows slowly; on the 6th day, scattered white mycelial spots appear on the liquid surface; on the 10th-15th day, the mycelial spots merge to form a complete, continuous white mycelial membrane with a thickness of 4-6 mm. The mycelial membrane is undamaged, without air bubbles, and has good toughness and is not easy to tear; on the 16th-30th day, the mycelial membrane thickens to 5-8 mm).

[0088] (3) Semi-solid thickening Culture medium formulation: The same formulation as the liquid static film-forming culture medium was used, with the addition of 0.45% carrageenan (food grade, viscosity 1100-1300 mPa·s, to enhance gel stability). The mixture was heated to 95℃ and stirred for 35 min until the carrageenan was completely dissolved. Potassium dihydrogen phosphate and magnesium sulfate were added to adjust the osmotic pressure, and the pH was adjusted to 6.8. The mixture was then autoclaved at 121℃ and 0.1 MPa for 20 min, cooled to about 42℃, and poured into sterile shallow dishes (same as the liquid film-forming shallow dishes). After cooling and solidification, a semi-solid gel was formed (gel thickness 1.5±0.1 cm, uniform texture, no lumps, no bubbles, and moderate gel hardness to facilitate mycelial penetration and nutrient absorption).

[0089] Operating details: In a sterile laminar flow hood, gently lift the intact mycelial membrane after liquid culture with sterile tweezers (be gentle to avoid damage), and lay it flat on the surface of the semi-solid gel, ensuring that the mycelial membrane and gel are completely adhered, without air bubbles or wrinkles, and that the edges are aligned with the inner wall of the shallow dish; place the shallow dish in a constant temperature incubator and incubate at 26±0.5℃ in the dark for 7-14 days, observing the mycelial growth regularly every day. After the culture is completed, the mycelial layer will have fully absorbed nutrients from the gel, thickened to 10.0±0.2mm, and become dense and felt-like, with a tough and firm feel. After separation from the gel, there will be no residual adhesion, and the overall integrity of the mycelial layer will be good.

[0090] (4) Solid cultivation and environmental induction to solidify Transfer procedure: Select a stainless steel perforated mesh plate (0.4 mm aperture, uniform mesh distribution to prevent mycelial layer from falling off). Lay a layer of sterile filter paper (120 g / m²) flat under the mesh plate. Spray the filter paper with sterile deionized water (the humidity should be controlled at 65% of the filter paper's saturated moisture content, i.e., the filter paper should not drip water and should feel moist to the touch, avoiding excessive humidity that could breed bacteria). Ensure there are no solid particles (to avoid introducing impurities, maintain the characteristics of pure mycelium, and prevent affecting the purity of the hard fiber material). Gently peel off the 10 mm thick semi-solid thickened mycelial layer with sterile tweezers and lay it flat on the perforated mesh plate. The mycelial layer should be laid flat, without overlap or damage. Place the mesh plate in a sterile incubator with a 5 cm gap between each other to avoid blocking light.

[0091] Four-dimensional regulation + UV-A irradiation (total duration 12 days, precise staged control to enhance mycelial rigidity): a. Temperature: The temperature is controlled at 30±0.5℃ throughout the process, under dark conditions (the incubator is protected from light, and the light intensity is ≤5 Lux). The stable high temperature environment promotes the thickening of the mycelial cell wall and avoids the impact of temperature fluctuations on the mycelial densification and hardening process. b. Irradiation: A combination of "blue light + low-dose UV-A irradiation" was adopted. Starting from the first day of cultivation, a 460±10 nm blue LED lamp was turned on (20 cm away from the mycelial surface), with a stable light intensity of 320±20 Lux, for 24 hours of continuous illumination. At the same time, a UV-A lamp (wavelength 320-400 nm, 30 cm away from the mycelial surface) was turned on for low-dose irradiation, with the irradiation intensity controlled at 50±5 μW / cm², for 2 hours per day (divided into two 1-hour sessions, 10:00-11:00 and 16:00-17:00 respectively). This avoided damage to the mycelium from high-dose UV-A and promoted the deposition of substances (chitin, glucan, etc.) inside and outside the mycelial cell wall through low-dose irradiation, further enhancing the mycelial rigidity. c. Gas: The incubator is sealed and uses a sterile mixed gas (containing 5.5±0.5% CO2, 20±0.5% O2, and the remainder being nitrogen) which is introduced into the incubator through sterile tubing. The number of air exchanges is controlled at once every 10 hours, with each air exchange lasting 30 seconds. This maintains a stable gas concentration in the incubator, limits the oxygen supply, promotes the lateral interweaving and density of mycelia, and improves the overall hardness of the material. d. Humidity: The relative humidity inside the incubator is controlled at 85±5% throughout the process (using a sterile humidifier, monitored 3 times a day at 8:00, 14:00 and 20:00 respectively) to avoid contamination by miscellaneous bacteria due to excessive humidity, and to prevent mycelium from drying out and cracking due to excessive humidity, thus ensuring normal mycelial growth and hardening.

[0092] After the regulation was completed, the mycelial layer was significantly densified and hardened, with a thickness of 5±0.2 mm. It was hard, tough, and free from looseness or adhesion. The mycelia were tightly interwoven, and the cell walls were significantly thickened.

[0093] (5) Stripping and post-processing Peeling Operation: Gently peel off the complete pure Ganoderma lucidum mycelium layer from the mesh plate with tweezers (at this time, the mycelium layer is not adhered to the mesh plate and filter paper, can be peeled off completely, has no broken edges, and is hard and not easily broken); spread the peeled mycelium layer flat on a baking tray and place it in a constant temperature oven. First, inactivate it at 90±1℃ for 2.5 hours (to completely kill the mycelium activity, prevent subsequent mold growth, and further solidify the mycelium structure), then adjust the oven temperature to 65±1℃ and continue drying until the moisture content of the mycelium layer is 7.5±0.5% (turn it over once every 2 hours during the drying process to ensure uniform drying; the moisture content is tested with a moisture analyzer, and 3 samples are tested for each batch, and the average value is taken); after drying, the mycelium layer is hard and dense, the thickness becomes 2.2±0.1 mm, the surface is light yellow, and there is no odor.

[0094] (6) Hot pressing Equipment: Flat plate hot press (pressure accuracy ±0.5 MPa, temperature accuracy ±1℃, with constant temperature and pressure function); the hot press mold is a smooth stainless steel mold (size: 30 cm × 20 cm). The mold surface is wiped with sterile gauze and a small amount of sterile silicone oil is applied (to avoid adhesion and not affect the purity of the material). The mold is preheated to 175℃ for use.

[0095] Hot pressing conditions: Spread the dried mycelium layer evenly in the center of the preheated mold, ensuring it is flat and free of wrinkles and overlaps; apply pressure of 20±0.5 MPa and hold for 12±0.5 minutes (extending the holding time ensures that the mycelium layer is fully integrated and densified, further improving hardness); during hot pressing, slowly expel air from the mold (to avoid air bubbles and pores in the finished product, which would affect the material's hardness and appearance); after hot pressing, allow it to cool naturally to room temperature (approximately 25°C) before demolding to avoid sudden cooling that could cause the material to crack.

[0096] Finished product specifications: A pure Ganoderma lucidum mycelium hard fiber material with a thickness of 1.0±0.1 mm, pale yellow in appearance, with a natural Ganoderma lucidum mycelium interwoven texture on the surface (clear texture, no obvious defects, uniform texture); tested, tensile strength is 10±0.3 MPa, elongation at break is 8±1% (significant hardness, elongation lower than oyster mushroom mycelium leather), hardness (Shore D) is 68±2, moisture content is 7.5±0.5%, odorless, free of bacteria, hard in texture, and with good toughness. See the product description below. Figure 3 .

[0097] Comparative Example 2 Similar to Example 2, except that in the case of liquid static film formation, the glucose concentration in the culture medium formulation is 20 g / L.

[0098] Experimental Example 2 Performance tests were conducted on the materials obtained in Example 2 and Comparative Example 2. (1) Mycelial layer thickness (mm) Using a digital vernier caliper or thickness gauge, measure the thickness at at least eight locations, including the center of the sample, the midpoints of its four sides, and its four corners. Take the arithmetic mean as the final thickness value. The instrument must be calibrated before measurement, and each sample should be measured three times.

[0099] (2) Density of the hyphal layer Qualitative analysis: Visual and microscopic observation of the amount of voids in the mycelial layer and whether the structure is compact; Quantitative analysis: Density was characterized by a density test (mass / volume, g / cm³). The mass m of the specimen was weighed using an electronic balance (accuracy 0.001 g); the length and width of the specimen were measured using digital vernier calipers, and the cross-sectional area S was calculated; the original thickness T of the specimen was measured. The density was calculated using the following formula: ρ=m / (S×T)×10 3 In the formula: ρ is the density of the specimen (g / cm³); m is the mass of the specimen (g); S is the cross-sectional area of ​​the specimen (mm²). 2 ); T is the original thickness of the specimen (mm).

[0100] (3) Qualitative evaluation of the toughness of the mycelial layer Qualitative analysis: Observe whether the mycelial layer is easily broken or delaminated through manual bending and stretching tests; Quantitative testing: Universal testing machine: According to GB / T 528–2009 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber", mechanical properties such as tensile strength rate were tested.

[0101] (4) Color of the mycelial layer Visually observe the overall color of the mycelial layer and whether its distribution is uniform, and record the color (e.g., light brown, yellowish brown, etc.).

[0102] The results are shown in Table 2 below.

[0103] Table 2

[0104] Table 2 shows that high glucose concentration can provide sufficient nutrition for long-term mycelial growth, resulting in vigorous intracellular polysaccharide synthesis and metabolism, promoting the deposition of cell wall polysaccharides such as chitin and β-glucan; and the formation of high surface tension promotes mycelial aggregation, thus significantly promoting the thickening of the Ganoderma lucidum mycelial layer. Simultaneously, it was found that the density and toughness of the mycelial layer increased, improving the uniformity of its color.

[0105] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing pure edible fungi mycelial fiber material, characterized in that, Includes the following steps: S1. Activation of microbial strains: Edible fungi strains are inoculated into suitable PDA medium and activated under dark conditions to obtain activated microbial strains; S2. Liquid static film formation: The above-mentioned activated bacterial strains are inoculated into a suitable liquid culture medium and statically cultured in the dark to form an initial mycelial film at the liquid-gas interface. S3, Semi-solid thickening: The initial mycelial membrane is peeled off and transferred to the surface of a semi-solid culture medium for culture, resulting in a thickened mycelial layer; S4. Solid cultivation and environmental induction for densification and solidification: The thickened mycelial layer is peeled off and transferred to a solid cultivation environment containing a support carrier. By comprehensively controlling the temperature, light, gas composition and humidity, the mycelium is induced to densify and solidify itself to obtain a pure mycelial fiber dense layer. S5. Peeling and post-treatment: Peel the above-mentioned dense layer of pure mycelial fibers from the support carrier, inactivate it first, and then dry it to a moisture content of 7.5-8.0% to obtain a dry pure mycelial fiber layer. S6. Hot pressing molding: The above-mentioned dried pure mycelium fiber layer is molded to obtain pure edible fungus mycelium fiber material.

2. The preparation method according to claim 1, characterized in that, Edible fungi include at least one of oyster mushrooms and reishi mushrooms; and / or The activation culture temperature is 24~26℃; the activation culture time is 6~10 days.

3. The preparation method according to claim 2, characterized in that, In S1, the edible fungus is oyster mushroom; the oyster mushroom strain is a wide-temperature type oyster mushroom strain; The PDA medium suitable for the oyster mushroom strain is a basic PDA medium; the basic PDA medium consists of: 200 g / L potato, 20 g / L glucose, 18-20 g / L agar, and distilled water to a final volume of 1000 mL, with a pH of 6.0-6.5; and / or In S1, the edible fungus is Ganoderma lucidum; The PDA medium suitable for Ganoderma lucidum strains is an optimized PDA medium; the optimized PDA medium consists of: 200 g / L potato, 25 g / L glucose, 18-20 g / L agar, and distilled water to a final volume of 1000 mL, with the pH adjusted to 5.8±0.

1.

4. The preparation method according to claim 2, characterized in that, In S2, the static culture temperature is 24~26℃; the static culture time is 20~30 days; and / or In S2, the suitable liquid culture medium composition for activated oyster mushroom spawn is: glucose 50.0±0.5 g / L, peptone 2.0±0.1 g / L, yeast extract 1.0±0.05 g / L, distilled water to a final volume of 1000 mL, and pH adjusted to 6.2±0.1; and / or In S2, the liquid culture medium suitable for activated Ganoderma lucidum strains consists of: glucose 55.0±0.5 g / L, peptone 2.5±0.1 g / L, yeast extract 1.5±0.05 g / L, potassium dihydrogen phosphate 1.0 g / L, magnesium sulfate 0.5 g / L, and distilled water to a final volume of 1000 mL, with the pH adjusted to 6.8±0.

1.

5. The preparation method according to claim 1, characterized in that, In S3, the incubation time on the surface of the semi-solid culture medium is 7-14 days, and / or In S3, the semi-solid culture medium is based on the liquid culture medium described in S2, with the addition of a coagulant with a mass fraction of 0.2%-0.8%. Preferably, the coagulant includes at least one of agar, carrageenan, gellan gum, or sodium alginate.

6. The preparation method according to claim 1, characterized in that, In S4, the solid-state cultivation environment includes temperature, light, gas composition, and humidity; The temperature ranges from 28 to 31°C. Humidity: Relative humidity 80~90%; Illumination: In dark conditions, use blue light irradiation or a combination of blue light and low-dose UV-A irradiation; Gas: The incubator is sealed and uses a sterile mixed gas, which is introduced into the incubator through sterile tubing. The number of gas exchanges is controlled to be once every 8 to 10 hours, and the time for each gas exchange is 25 to 35 seconds.

7. The preparation method according to claim 6, characterized in that, Dark conditions refer to the incubator being kept completely dark, with a light intensity ≤5 Lux; and / or The specific method of using blue light irradiation is as follows: starting from day 1 of cultivation, turn on the blue LED light, maintain a stable light intensity of 280~340 Lux, and provide continuous 24-hour illumination without interruption; and / or The specific method of using low-dose UV-A irradiation is as follows: turn on the UV-A ultraviolet lamp, irradiate with low dose, control the irradiation intensity at 40~60 μW / cm², and irradiate for 2 hours per day.

8. The preparation method according to claim 1, characterized in that, In S4, the solid culture environment contains a support carrier; Preferably, the support carrier is a combination of a stainless steel porous mesh plate and sterile moistened filter paper. More preferably, the stainless steel porous mesh plate has a pore size of 0.3~0.6 mm, the sterile moistened filter paper has a basis weight of 120 g / m², and the wettability is 60~68% of the filter paper's saturated moisture content; and / or In S5, the inactivation temperature is 85-90℃; the inactivation time is 2-2.5 hours; the drying temperature is 60-65℃; and / or S6 also includes demolding after compression molding, holding pressure, and naturally cooling to room temperature; Preferably, the molding temperature is 160-175℃; the molding pressure is 15-20 MPa; and the holding time is 10-12 minutes.

9. Pure edible fungi mycelial fiber material prepared by the preparation method according to any one of claims 1 to 8.

10. The application of the pure edible fungus mycelium fiber material according to claim 9 in the preparation of imitation leather materials and decorative finishing materials.

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