Method for preparing mycelium fiber membrane based on DES-electrostatic spinning of mycelium leather waste

Abstract

The invention belongs to the technical field of mycelium leather waste treatment, and particularly relates to a method for preparing a mycelium fiber membrane based on mycelium leather waste through DES-electrostatic spinning. The preparation method comprises the following steps: dissolving mycelium leather waste by DES obtained by mixing choline chloride and glycerol to obtain a mycelium dissolving solution, uniformly mixing the mycelium dissolving solution with a spinning aid to obtain a mycelium base solution, and preparing the mycelium base solution into the mycelium nanofiber membrane through electrostatic spinning. According to the method, the DES can efficiently destroy mycelium cell walls, the dissolution rate can be increased to be larger than or equal to 80%, and the nanofiber film obtained through electrostatic spinning has good air permeability; the invention provides an innovative solution for resource utilization of mycelium leather wastes.

Description

Technical Field

[0001] The present invention belongs to the technical field of mycelium leather waste treatment, and particularly relates to a method for preparing mycelium fiber membranes by DES-electrospinning of mycelium leather waste. Background Art

[0002] Mycelium, composed of hyphae from higher fungi, can form a dense network structure through solid-state cultivation, exhibiting excellent mechanical properties and plasticity. Mycelial leather, derived from a single, network-like layer of mycelial fibers, is produced through tanning and other methods to create a new material similar to animal leather, offering advantages such as environmental friendliness, biodegradability, and renewability. However, the production process generates waste due to trimming and sanding. Currently, the primary disposal methods are landfill or incineration, resulting in resource waste and environmental pollution. Current fungal extraction methods typically utilize aqueous extraction combined with physical assistance techniques (such as heating, ultrasound, and microwaves). However, the mycelial cell wall is rich in chitin and has a dense structure, making traditional dissolution methods inefficient. Treatment with organic solvents can easily lead to secondary pollution and harm human health. Inadequate dissolution prevents high-value utilization. Furthermore, the presence of impurities such as tanning agents and fillers in mycelial leather waste further complicates extraction. Deep eutectic solvents (DES), as green solvents, offer low volatility, low cost, and excellent biocompatibility, significantly outperforming traditional organic solvents and can be used for material modification and processing. Addressing the challenges of mycelial leather waste's dense structure and the low efficiency of traditional dissolution methods, DES treatment can effectively improve dissolution efficiency while reducing the negative environmental impacts of solvent treatment. Summary of the Invention

[0003] The drum tanning process of Ganoderma mycelium produces mycelium-based leather waste, which, in addition to a mycelium content exceeding 80%, may also contain tanning agents, retanning agents, fillers, dyes, finishing agents, and other essential chemical additives required for the production of mycelium-based leather. The present invention addresses the problems of low dissolution efficiency, poor fiber uniformity, and toxic pollution from organic solvents (such as DMF) in the existing high-value utilization of leather-like waste. It provides a green and efficient resource utilization method and an innovative dissolution process: a deep eutectic solvent (DES) is used to destroy the dense cell walls of the mycelium to increase the dissolution rate, thereby effectively extracting mycelium fibers. By optimizing the dissolution-centrifugation-spinning process parameters, an ultrafine nanofiber membrane with high porosity is produced. This membrane not only enhances spinning stability but also achieves environmental friendliness, providing a sustainable material solution for the resource utilization of mycelium-based waste.

[0004] In order to achieve the above object, the present invention provides the following technical solutions: A method for preparing mycelial fiber membrane by DES-electrospinning of mycelial leather waste comprises the following steps: (1) Preparation of DES (deep eutectic solvent): Mix choline chloride and glycerol evenly; (2) Dissolving: using the DES obtained in step (1) to dissolve the mycelium leather waste, homogenize it, and then filter to obtain a mycelium solution; (3) Mixing: Evenly mixing the mycelium dissolving solution in step (2) with the spinning aid to obtain a mycelium base liquid; (4) Spinning membrane: The mycelium base liquid is prepared into mycelium nanofiber membrane by electrospinning.

[0005] Preferably, the mycelium leather waste in step (1) is waste obtained by drum tanning of Ganoderma lucidum mycelium, with a mycelium content of more than 80%, and also includes tanning agent, retanning agent, and filler impurities; the molar ratio of choline chloride to glycerol in step (1) is 1: (1-5). At this ratio, DES can effectively dissolve the mycelium leather waste without adding a separate impurity removal process.

[0006] Preferably, in step (1), the temperature is 70-100° C., stirring and mixing are adopted, the stirring rate is 200-500 rpm, and the mixing time is 1-3 h.

[0007] Preferably, in step (2), the mycelium-based leather waste is crushed and sieved through a 10-mesh sieve to obtain mycelium-based leather waste powder, and the mycelium-based leather waste powder is dissolved under stirring, the dissolution time is 9-15 hours, the temperature is 70-100° C., and the stirring rate is 200-500 rpm.

[0008] Preferably, in step (2), the mass ratio of the mycelium leather waste powder to DES is 1:2-1:20. After dissolution, it needs to be simply filtered through filter paper / gauze.

[0009] Preferably, in step (3), the mixture is mixed under stirring, the mass / volume ratio of the spinning aid to the mycelium dissolution liquid is 1 g: (20-60) mL, the stirring rate is 200-500 rpm, and the temperature is 20-40°C.

[0010] Further preferably, in step (3), the spinning aid is polyvinyl alcohol (PVA), polyethylene oxide (PEO) or polyvinyl pyrrolidone (PVP).

[0011] Preferably, in step (4), the electrospinning conditions are as follows: during the spinning process, the mycelium base liquid flow rate is 0.05-0.2 mL / h, the voltage is 7-18 kV, and the needle-flat collector distance is 15-30 cm.

[0012] The present invention also provides a mycelium nanofiber membrane prepared by the method.

[0013] The mycelium nanofiber membrane of the present invention has broad application prospects in the fields of biomedicine and food packaging.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The present invention relates to a method for preparing an electrospun nanofiber film from mycelium leather waste treated with DES (deep eutectic solvent). This method achieves a breakthrough in dissolution efficiency: DES (choline chloride / glycerol system) efficiently destroys the mycelium cell wall, and the dissolution rate can be increased to ≥80%. The nanofiber film is obtained through electrospinning and has good air permeability. The present invention provides an innovative solution for the resource utilization of mycelium leather waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings: Figure 1 The mycelium lysate obtained by treating mycelium waste with DES in Example 1; Figure 2 This is the mycelium nanofiber membrane prepared by electrospinning in Example 1. DETAILED DESCRIPTION

[0016] The present invention will be further described below in conjunction with specific embodiments, and the advantages and features of the present invention will become clearer as the description proceeds. However, the embodiments are merely exemplary and do not limit the scope of the present invention in any way. It should be understood by those skilled in the art that the details and forms of the technical solutions of the present invention may be modified or replaced without departing from the spirit and scope of the present invention, and such modifications and replacements fall within the scope of protection of the present invention.

[0017] The raw materials in the following examples are all mycelium leather waste generated during the drum tanning production process of Ganoderma lucidum mycelium. The mycelium content exceeds 80%, and the materials contain but are not limited to tanning agents, retanning agents, fillers, finishing agents and other types of impurities. The impurity components are determined by the mycelium leather production process. The waste is uniformly collected from the finished product trimming and is not differentiated.

[0018] Example 1 A method for preparing mycelial fiber membrane by DES-electrospinning of mycelial leather waste comprises the following steps: (1) According to the molar ratio of choline chloride to glycerol (glycerin) of 1:2, weigh 76 g of choline chloride and 100 g of glycerin, mix the two, and heat and stir in a magnetic stirrer (400 rpm, 90°C) for 2 h until it becomes a transparent liquid.

[0019] (2) The mycelium leather waste was crushed and sieved through a 10-mesh sieve to obtain mycelium leather waste powder. 12.5 g of mycelium leather waste powder was added to 100.75 g of DES, and the mixture was stirred under a magnetic stirrer (400 rpm, 90° C.) for 12 h to finally obtain a mycelium solution in the form of a brown viscous mixture, as shown in FIG. Figure 1 As shown in .

[0020] (3) Mix 0.375 g of PVA with 15 ml of filtered mycelium solution and stir (400 rpm) until the PVA is completely dissolved (12 h, 25°C).

[0021] (4) The mycelium nanofiber membrane obtained by spinning was prepared by electrospinning (solution flow rate of 0.10 mL / h, voltage of 13.5 kV, needle-flat collector distance of 25 cm). Figure 2 As shown in .

[0022] The undissolved mycelium leather waste powder was washed, dried, weighed, and the dissolution rate was calculated. The results are shown in Table 1.

[0023] Example 2 A method for preparing mycelial fiber membranes by DES-electrospinning of mycelial leather waste comprises the following steps: (1) weighing 76 g of choline chloride and 100 g of glycerol in a molar ratio of 1:2, mixing the two, and heating and stirring them in a magnetic stirrer (400 rpm, 90°C) for 2 h until a transparent liquid is obtained.

[0024] (2) 25.0 g of mycelial leather waste powder was dissolved in 100.75 g of DES and stirred under a magnetic stirrer (400 rpm, 90 °C) for 12 h to obtain a mycelial solution of a brown viscous mixture.

[0025] (3) Mix 0.429 g of PEO with 15 ml of filtered mycelium solution and stir (400 rpm) until the PEO is completely dissolved (8 h, 25°C).

[0026] (4) Spinning was performed using an electrospinning machine (solution flow rate was 0.15 mL / h, voltage was 17.5 kV, and needle-flat collector distance was 20 cm).

[0027] The undissolved mycelium leather waste powder was washed, dried, weighed, and the dissolution rate was calculated. The results are shown in Table 1.

[0028] Example 3 A method for preparing mycelial fiber membranes by DES-electrospinning of mycelial leather waste comprises the following steps: (1) weighing 76 g of choline chloride and 100 g of glycerol in a molar ratio of 1:2, mixing the two, and heating and stirring them in a magnetic stirrer (400 rpm, 90°C) for 2 h until a transparent liquid is obtained.

[0029] (2) 50.0 g of mycelial leather waste powder was dissolved in 100.75 g of DES and stirred for 12 h under a magnetic stirrer (400 rpm, 90 °C) to obtain a mycelial solution of a brown viscous mixture.

[0030] (3) Mix 0.300 g of PVP with 15 ml of filtered mycelium solution and stir (400 rpm) until the PVP is completely dissolved (10 h, 25°C).

[0031] (4) Spinning was performed using an electrospinning machine (solution flow rate was 0.15 mL / h, voltage was 18.0 kV, and needle-flat collector distance was 15 cm).

[0032] The undissolved mycelium leather waste powder was washed, dried, weighed, and the dissolution rate was calculated. The results are shown in Table 1.

[0033] Comparative Example 1 25 g of mycelial leather waste powder was added to 100 g of water (400 rpm, 90°C) and stirred for 12 h.

[0034] 0.375 g of PVA was mixed with 15 ml of the filtered mycelial solution and stirred (400 rpm) until the PVA was completely dissolved (12 h, 25°C).

[0035] After spinning through an electrospinning machine (solution flow rate of 0.15 mL / h, voltage of 17.5 kV, needle-flat collector distance of 20 cm), no filament could be formed.

[0036] Comparative Example 2 Choline chloride and glycerol (glycerol) were mixed in a molar ratio of 5:1 and heated and stirred in a magnetic stirrer (400 rpm, 90°C) for 2 hours, but no transparent liquid could be obtained.

[0037] Comparative Example 3 (1) Choline chloride and glycerol (glycerol) were mixed in a molar ratio of 1:10 and heated and stirred in a magnetic stirrer (400 rpm, 90°C) for 2 h to obtain a transparent viscous liquid.

[0038] (2) 25 g of mycelium leather waste powder was added to the liquid in (1) at a mass ratio of 1:1, 1:5, and 1:10 (400 rpm, 90°C) and stirred for 12 h. The solubility was very low and it could not be fully dissolved.

[0039] The undissolved mycelium leather waste powder was washed, dried, weighed, and the dissolution rate was calculated. The results are shown in Table 1.

[0040] Table 1. Dissolution rates of Examples 1-3 and Comparative Example 1

Claims

1. A method for preparing mycelial fiber membrane by DES-electrospinning of mycelial leather waste, characterized in that: The following steps are involved: (1) Preparation of DES: Mix choline chloride and glycerol evenly; (2) Dissolving: evenly dissolving the mycelium leather waste in the solution obtained in step (1) to obtain a mycelium solution; (3) Mixing: Evenly mixing the mycelium dissolving solution in step (2) with the spinning aid to obtain a mycelium base liquid; (4) Spinning membrane: The mycelium base liquid is prepared into mycelium nanofiber membrane by electrospinning.

2. The method for preparing mycelial fiber membrane by DES-electrospinning of mycelial leather waste according to claim 1, characterized in that: The mycelium leather waste in step (1) is waste obtained by drum tanning of Ganoderma lucidum mycelium, and the mycelium content is above 80%. It also includes tanning agent, retanning agent, and filler impurities. When dissolved, the molar ratio of choline chloride to glycerol is 1: (1-5).

3. The method for preparing mycelial fiber membrane by DES-electrospinning of mycelial leather waste according to claim 1, characterized in that: In step (1), the mixing temperature is 70-100° C., the mixing is carried out by stirring, the stirring rate is 200-500 rpm, and the mixing time is 1-3 h.

4. The method for preparing mycelial fiber membrane by DES-electrospinning of mycelial leather waste according to claim 1, characterized in that: In step (2), the mycelium leather waste is crushed and sieved through a 10-mesh sieve to obtain mycelium leather waste powder, and the mycelium leather waste powder is dissolved in DES under stirring at a dissolution temperature of 70-100°C, a time of 9-15 hours, and a stirring rate of 200-500 rpm.

5. The method for preparing mycelial fiber membrane by DES-electrospinning of mycelial leather waste according to claim 4, characterized in that: In step (2), the mass ratio of the mycelium leather waste powder to DES is 1:(2-20). After dissolution, it needs to be simply filtered through filter paper / gauze.

6. The method for preparing mycelial fiber membrane by DES-electrospinning of mycelial leather waste according to claim 1, characterized in that: In step (3), the mixture is mixed under stirring at a temperature of 20-40° C., the mass / volume ratio of the spinning aid to the mycelium dissolution liquid is 1 g: (20-60) mL, and the stirring rate is 200-500 rpm.

7. The method for preparing mycelial fiber membrane by DES-electrospinning of mycelial leather waste according to claim 1, characterized in that: In step (3), the spinning aid is polyvinyl alcohol, polyethylene oxide or polyvinyl pyrrolidone.

8. The method for preparing mycelial fiber membrane by DES-electrospinning of mycelial leather waste according to claim 1, characterized in that: In step (4), the electrospinning conditions are as follows: during the spinning process, the mycelium base liquid flow rate is 0.05-0.2 mL / h, the voltage is 7-18 kV, and the needle-flat collector distance is 15-30 cm.

9. A mycelium nanofiber membrane prepared according to the method according to any one of claims 1 to 8.

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