Method for preparing a biofiber facial mask fabric and biofiber facial mask fabric obtained thereby

Abstract

The present invention provides a method for preparing a biofiber facial mask cloth, which comprises the following steps: (1) activating and subculturing Acetobacter xylinum to obtain a subcultured Acetobacter xylinum culture solution; (2) uniformly inoculating about 1-15%, preferably about 5-10% of the subcultured Acetobacter xylinum culture solution into a culture medium, and performing fermentation culture at a temperature of about 25-35°C, preferably about 25-30°C for about 2-5 days, preferably about 2-3 days, wherein the culture medium contains more than about 18%, preferably more than about 27%, more preferably more than about 36% and most preferably more than about 45% of birch sap and about 0-71%, preferably about 10-62%, more preferably about 30-53% of coconut water, wherein all the above content percentages are based on the total weight of the fermentation broth; and (3) collecting the film.

Description

Technical Field

[0001] The present invention relates to a method for preparing a biological fiber facial mask cloth and a biological fiber facial mask cloth obtained by the method. Background Art

[0002] Currently, beauty and skin care facial masks on the market are usually made of artificial fiber non-woven fabrics or chemical synthetic fiber non-woven fabrics through subsequent processing. However, these non-woven fabric-based facial masks have some defects and deficiencies. For example, they have poor affinity with the skin, general air permeability, unsatisfactory penetration effect of active substances, and are easy to crack from the right-angle direction because the fibers are arranged in a certain direction. Moreover, when the facial mask is applied for too long, a "reverse absorption" phenomenon will occur. In addition, using non-woven fabric as the facial mask cloth can only be used as a carrier for facial mask liquid, without other additional values, and it is derived from petrochemical industry, so it has poor environmental friendliness.

[0003] Biological fiber facial mask is a new type of facial mask. It is a biological cellulose film made by natural fermentation of microorganisms, has functions similar to the skin, can permeate oxygen and isolate bacteria. Coconut water is the earliest and currently commonly used raw material for producing this biological cellulose film. In recent years, biological cellulose has been widely used in many fields such as medical treatment, textile, environmental protection, and papermaking because of its excellent properties, resulting in a huge demand for it. However, as the main production raw material, coconut water has geographical limitations. Therefore, finding a substitute for coconut water as the raw material for producing biological cellulose has become a research hotspot.

[0004] Chinese Patent Application No. 201110176434.3 discloses a method for preparing biological cellulose using inulin as a carbon source, which has the advantages of wide raw material sources, low cost, and strong operability. The yield of producing biological cellulose using inulin is higher than that using other glucose and / or fructose, and can reach up to twice as much. However, the tensile strength and moisture content of the organic fiber film obtained using inulin are the lowest.

[0005] Chinese Patent Application No. 201510942260.5 discloses a method for preparing biological cellulose using an optimized watermelon juice culture medium. By screening the main components in the watermelon juice culture medium, determining the key factors and then optimizing them, the obtained biological cellulose is better than the basic watermelon juice culture medium in terms of water retention, crystallinity, and thermal stability.

[0006] Chinese Patent Application No. 201310314954.5 discloses a method for preparing a biological fiber facial mask with anti-radiation efficacy. By using the ultrasonic method to extract total flavonoids from natural plants and using the alcohol solution containing total flavonoids as a culture medium to ferment biological cellulose materials, a biological fiber facial mask is prepared, which can eliminate excessive active oxygen free radicals on the face and has anti-radiation efficacy.

[0007] However, in the prior art, the biocellulose membranes obtained by fermentation can only improve one or two of the basic fiber properties, such as crystallinity and tensile strength, and such improvement is not significant. Moreover, the existing biocellulose membranes cannot meet the requirements of consumers for mildness, non-irritation, and improved skin care effects of the membrane cloth.

[0008] Therefore, there is a need for a new biocellulose facial mask cloth and a preparation method thereof that can overcome the deficiencies existing in the above-mentioned prior art biocellulose facial mask cloth.

[0009] Brief Description of the Drawings

[0010] Figure 1 and Figure 2 respectively show the promotion of the penetration of the active ingredient carnosine in Sample 1 of the present invention and Control Samples 2 and 3.

[0011] Figure 3 Shows the efficacy of Sample 1 of the present invention and Control Sample 3 in improving skin firmness. Summary of the Invention

[0012] On the one hand, the present invention provides a method for preparing a biocellulose facial mask cloth, which includes the following steps:

[0013] (1) Activating and subculturing Acetobacter xylinum to obtain a subcultured Acetobacter xylinum culture solution;

[0014] (2) Uniformly inoculating about 1-15%, preferably about 5-10% of the subcultured Acetobacter xylinum culture solution into a culture medium, and performing fermentation culture at a temperature of about 25-35°C, preferably about 25-30°C for about 2-5 days, preferably about 2-3 days, wherein the culture medium contains more than about 18%, preferably more than about 27%, more preferably more than about 36%, and most preferably more than about 45% of birch sap and about 0-71%, preferably about 10-62%, more preferably about 30-53% of coconut water, wherein all the above content percentages are based on the total weight of the fermentation broth (the fermentation broth is composed of the culture medium and the Acetobacter xylinum culture solution); and

[0015] (3) Collecting the film.

[0016] The activation and subculture of Acetobacter xylinum in the above step (1) are known in the art. For example, it is usually carried out as follows:

[0017] a. Activation

[0018] Take an appropriate amount of Acetobacter xylinum out of the refrigerator and thaw it at room temperature. Add it to the first liquid medium, then add about 5 - 15 ml of ethanol with a volume concentration of 95% to the medium, and culture it in a shaker at about 25 - 35 °C and about 170 - 190 rpm for about 36 - 54 h to obtain an activated Acetobacter xylinum culture solution;

[0019] b. Subculture of the strain

[0020] Take the activated Acetobacter xylinum culture solution accounting for about 5 - 15% of the total weight of the medium and add it to the first liquid medium. Then add about 5 - 15 ml of ethanol with a volume concentration of 95% to the medium, and then culture it in a shaker at about 25 - 35 °C and about 170 - 190 rpm for about 18 - 30 h to obtain a subcultured Acetobacter xylinum culture solution;

[0021] The Acetobacter xylinum is a commonly used strain in the field of producing biofiber facial mask cloth by fermentation. Its properties are known in the art and it can be commercially obtained. For example, it can be commercially purchased from Shanghai Lianmai Bioengineering Co., Ltd.

[0022] The first liquid medium is known in the art. By weight, it usually contains about 2 - 10% carbon source, about 0.1 - 10% nitrogen source, and about 0 - 10% inorganic salts, with the balance being pure water. The carbon source is known in the art and includes, for example, glucose, lactose, sucrose, ethanol, hexanediol, glycerol lactose, and mannose, etc. The nitrogen source is known in the art and includes, for example, yeast extract, peptone, L - glutamic acid, L - aspartic acid, L - alanine, etc. The inorganic salts are known in the art and include, for example, sodium pyrophosphate, sodium chloride, potassium chloride, magnesium sulfate, etc. Usually, a buffer solution such as phosphate buffer solution, etc., can be used to adjust the pH value of the first liquid medium to, for example, about 4.0 - 6.0. Usually, the first liquid medium can be sterilized in high - pressure steam at about 121 °C for about 30 min.

[0023] The medium used in step (2) contains more than about 18%, preferably more than about 27%, more preferably more than about 36%, and most preferably more than about 45% of birch sap and about 0 - 71%, preferably about 10 - 62%, more preferably 30 - 53% of coconut water, based on the total weight of the fermentation broth.

[0024] The birch sap is obtained from the genus Betula of the Betulaceae family, and it can come from varieties such as Betula alba, Betula pubescens, Betula Pendula, and Betula platyphyl la. The birch sap is a colorless, transparent, sediment-free, impurity-free, and nutritious juice with a fresh birch fragrance, which is collected by manually drilling holes at the base of the birch tree trunk between thawing and the emergence of leaves in early spring. The birch sap can be commercially purchased and used as it is. For example, it can be purchased from Daxing'anling Chaoyue Wild Berry Development Co., Ltd.

[0025] In the present invention, the birch sap that can be used is birch sap stock solution, fermented birch sap, or concentrated birch sap. Among them, the concentration multiple of the concentrated birch sap is about 1.05 - 10.0 times, preferably about 2.0 - 6.0 times. The fermented birch sap can be the fermented birch sap known in the art, such as the birch sap fermented by Inonotus obliquus disclosed in Chinese Patent CN110734932B, the birch sap fermented by yeast disclosed in CN112842976A and CN112842953A, etc. All of these are incorporated herein by reference.

[0026] The concentrated birch sap is obtained by concentrating a commercially available birch sap product. The concentration methods are known in the art, such as heat concentration, low-temperature vacuum concentration, membrane concentration, etc. In the present invention, it is preferably concentrated by low-temperature freezing concentration or membrane concentration process. For example, the commercially available birch sap stock solution is input into a low-temperature drying device, cooled to about -40°C to -70°C, and evacuated to about 0.1 - 30 Pa for low-temperature vacuum concentration, so as to obtain concentrated birch sap with different concentration multiples.

[0027] The coconut water is extracted from fresh coconuts. Coconuts are mainly planted in the southeastern coastal areas of Hainan. The coconut water can be directly extracted from coconuts or can be commercially purchased and used as it is. For example, it can be purchased from Wenchang Yedao Industry Co., Ltd.

[0028] As needed, the birch sap and coconut water can be filtered through a filter cloth with a mesh size of more than 300 meshes to remove impurities therein; and optionally, the medium can be sterilized at a temperature of about ≥95°C for about 10 minutes.

[0029] In addition to containing birch sap and coconut water, the medium can also contain carbon sources, inorganic salts, pH regulators, etc. The components and their contents are all known in the art.

[0030] The carbon source includes, for example, glucose, granulated sugar, fructose glucose, sucrose, galactose, glycerol lactose, mannose, etc. The content of the sugar source can be selected by those skilled in the art, and generally its content is about 0.5 - 1.5%, preferably about 0.7 - 1%, based on the total weight of the fermentation broth.

[0031] The inorganic salts include, for example, potassium dihydrogen phosphate, sodium dihydrogen phosphate, dipotassium hydrogen phosphate, disodium hydrogen phosphate, diammonium hydrogen citrate, sodium acetate, manganese sulfate, magnesium sulfate, potassium nitrate, etc. The content of the inorganic salts can be selected by those skilled in the art, and generally its content is about 0 - 2%, preferably about 0.2 - 1%, based on the total weight of the fermentation broth.

[0032] The pH regulator includes, for example, lactic acid, citric acid, ammonia water, sodium lactate, glacial acetic acid, sodium citrate, sodium hydroxide, etc., and preferably glacial acetic acid, etc. The pH regulator is added to the culture medium to adjust the pH of the culture medium to about 2.0 - 5.5, preferably about 3.0 - 4.5.

[0033] In the fermentation process of the above step (2), the subcultured Acetobacter xylinum culture solution accounting for about 1 - 15%, preferably about 5 - 10% based on the total weight of the fermentation broth is evenly inoculated into the culture medium, and fermentation culture is carried out at a temperature of about 25 - 35°C, preferably about 25 - 30°C for about 2 - 5 days, preferably about 2 - 3 days to obtain a biological fiber membrane sheet.

[0034] The film collection in the above step (3) is known in the art and generally includes, for example, washing, flattening, pressing water, cutting the shape, etc. of the obtained biological fiber membrane sheet to obtain a biological fiber facial mask cloth.

[0035] The biological fiber facial mask cloth obtained by the preparation method of the present invention generally has an average thickness of about 2.5 - 6.0 mm, preferably 3.0 - 6.0 mm, a mass of about 280 - 900 g / L, preferably 550 - 900 g / L (here it refers to the wet weight, and the unit g / L refers to the mass of the biological fiber facial mask produced per liter of the fermentation broth), and a tensile strength of about 0.5 - 4.5 N / mm 2 、preferably 0.9 - 4.0 N / mm 2 .

[0036] Moreover, the biological fiber facial mask cloth obtained by the preparation of the present invention has excellent permeability. For example, compared with the permeability of the biological fiber facial mask cloth obtained by fermenting only with coconut water, the biological fiber facial mask cloth of the present invention can increase the skin permeability of carnosine as an active substance by more than 2.5 times; compared with the permeability of a common tencel membrane cloth, the biological fiber facial mask cloth of the present invention can increase the skin permeability of carnosine as an active substance by more than 4 times.

[0037] In addition, the yield of the biofiber facial mask fabric prepared by the method of the present invention can reach about 4 g / L or more, where the unit g / L refers to the dry weight of the biofiber facial mask fabric produced per liter of the fermentation broth. Compared with the prior art method of preparing biofiber facial mask fabric only by fermenting coconut water, the preparation method of the present invention significantly increases the yield of the biofiber facial mask fabric, usually increasing the yield by about 200 - 270%. The best results are obtained when the fermentation broth contains about 40 - 50% of the original birch sap or fermented birch sap.

[0038] In another aspect, the present invention provides a biofiber facial mask fabric obtained by the above method, which has the average thickness and quality as described above, as well as excellent tensile strength and permeability enhancing property.

[0039] The interior of the biofiber facial mask fabric is a unique dense three-dimensional network structure composed of cellulose and has numerous micropores. This unique structure combined with the activity of the fermented birch sap itself enables the biofiber facial mask fabric to obtain many beneficial properties when contacting the skin, including, for example, excellent conformability, moisturizing property, soft feeling, high water retention capacity, good biocompatibility and biodegradability, mild and non-irritating, and excellent permeability enhancing property, etc.

[0040] The biofiber facial mask fabric can be used to carry the commonly used facial mask liquid known in the art.

[0041] At the same time, the biofiber facial mask fabric can not only serve as a carrier for the facial mask liquid, but also has good beauty effects itself, and can soothe and repair the skin, and is particularly suitable for the repair of sunburned skin and skin after medical beauty projects.

[0042] In addition, the biofiber facial mask fabric can also be used as a health food, which can regulate the body functions, promote intestinal peristalsis, improve the skin condition, whiten the skin, and delay skin aging. Examples

[0043] The present invention will be further described in detail below in conjunction with examples. However, it should be understood that these examples and comparative examples are only used to specifically illustrate the present invention, and should not be construed as limiting the scope of the appended claims of the present invention in any form.

[0044] Example 1: Preparation of biofiber facial mask fabric

[0045] In this example, birch sap or a mixture of it and coconut water was used, Acetobacter xylinum was used, and the culture medium formulation in Table 1 below (where the remaining components were 0.8% white granulated sugar and 0.2% sodium acetate respectively) was used to prepare the biofiber facial mask fabric, where the content was based on the total weight of the fermentation broth (i.e., the total weight of the culture medium and the Acetobacter xylinum culture solution).

[0046] Table 1

[0047] Example Betula platyphylla juice content Coconut water content Remaining components Strain content pH 1 89％ 0 1％ 10％ 3.84 2 45％ 44％ 1％ 10％ 3.49 3 27％ 62％ 1％ 10％ 3.47 4 18％ 71％ 1％ 10％ 3.45 5 (control) 9％ 80％ 1％ 10％ 3.41 6 (control) 0 89％ 1％ 10％ 3.37

[0048] The preparation steps are as follows:

[0049] (1) Activation and subculture of Acetobacter xylinum

[0050] a. Activation

[0051] Take out 10 ml of the preserved Acetobacter xylinum strain from the refrigerator and thaw it at room temperature. Add it to 500 g of the first liquid medium, then add 10 mL of ethanol with a volume concentration of 95% to the medium, and then activate and culture it in a shaker at 30 °C and 180 rpm for 50 h to obtain an activated Acetobacter xylinum culture solution.

[0052] The first liquid medium contains 10 g of glucose, 5 g of yeast extract, 2.5 g of peptone, 2.5 g of sodium pyrophosphate and the balance of pure water, and the total amount of the medium is 500 g. Adjust the pH value to 4.5 with phosphate buffer solution, put it into a 2 L conical flask, and seal it with a cotton plug. Sterilize it in high-pressure steam at 121 °C for 30 min.

[0053] b. Subculture

[0054] Take out 20 mL of the activated Acetobacter xylinum culture solution from the conical flask, add it to 500 g of the first liquid medium, then add 10 mL of ethanol with a volume concentration of 95% to the medium, and then culture it in a shaker at 30 °C and 180 rpm for 20 h to obtain a subcultured Acetobacter xylinum culture solution.

[0055] (2) Inoculation and fermentation culture

[0056] Uniformly inoculate 10% (based on the total weight of the fermentation broth) of the subcultured Acetobacter xylinum culture solution into the medium in a fermentation tray of 32 x 24 cm, and carry out fermentation culture at a temperature of 30 °C for 3 days; the formula of the medium is as described in Table 1 above.

[0057] (3) Film collection

[0058] Take out the formed biofiber membrane sheet, wash away the excess medium, soak it in a sodium percarbonate solution with a mass concentration of 0.5% until there is no acetic acid smell, then take out the membrane sheet and wash away the excess sodium percarbonate solution, measure the thickness, weight and yield of the obtained biofiber membrane sheet (its size is the size of the fermentation tray, 32 x 24 cm) after pressing out the water, and further cut it to obtain the biofiber membrane sheet, where the obtained values are the average values of 6 parallel experiments. The results are shown in Table 2 below.

[0059] Table 2

[0060] Example Thickness (mm) Weight (g) Yield (g / L) 1 4.70 772 3.9 2 5.07 865 4.1 3 3.31 630 3.2 4 3.15 587 3.0 5 (control) 2.35 342 1.8 6 (control) 2.04 283 1.5

[0061] Example 2: Preparation of a biofiber facial mask cloth

[0062] In this example, birch sap fermented by Inonotus obliquus disclosed in Chinese Patent CN110734932B or a mixture thereof and coconut water was used. The same Acetobacter xylinum culture solution as in Example 1 was used, and the culture medium formulation in Table 3 below was used (where the remaining components were 0.8% white granulated sugar and 0.2% sodium acetate respectively) to prepare a biofiber facial mask cloth, where the content was based on the weight of the fermentation broth (i.e., the total weight of the culture medium and the Acetobacter xylinum culture solution).

[0063] Table 3

[0064] Example Fermented Betula platyphylla juice content Coconut water content Remaining components Strain content pH 1 89％ 0％ 1％ 10％ 3.89 2 45％ 44％ 1％ 10％ 3.61 3 27％ 62％ 1％ 10％ 3.47 4 18％ 71％ 1％ 10％ 3.47 5 (control) 9％ 80％ 1％ 10％ 3.40 6 (control) 0％ 89％ 1％ 10％ 3.37

[0065] The preparation steps were the same as those described in Example 1.

[0066] The thickness, weight, and yield of the obtained biofiber facial mask cloth are shown in Table 4 below.

[0067] Table 4

[0068] Example Thickness (mm) Weight (g) Yield (g / L) 1 4.88 817 4.0 2 5.90 896 4.3 3 3.85 682 3.7 4 3.50 596 3.1 5 (control) 2.82 374 1.9 6 (control) 2.04 283 1.5

[0069] Example 3: Tensile properties of the biofiber facial mask cloth

[0070] In this example, the tensile properties of the biofiber facial mask cloths prepared in Examples 1 and 2 were further investigated, where the tensile properties were tested according to the standard GB / T 24218.3 "Test Method for Tensile Strength". The results are shown in Table 5 below, where the tensile strength values are the averages of the results of 6 parallel experiments.

[0071] Table 5

[0072] Examples in Example 1 <![CDATA[Tensile strength (N / mm 2 )]]> Examples in Example 2 <![CDATA[Tensile strength (N / mm 2 )]]> 1 1.216 1 4.020 2 1.052 2 3.642 3 0.980 3 2.295 4 0.927 4 3.275 5 (control) 0.734 5 (control) 1.809 6 (control) 0.741 6 (control) 0.741

[0073] From the results of the thickness, weight, tensile strength, and yield of the obtained biofiber membrane sheets above, it can be seen that the results are optimal when the fermentation broth contains 45% of the original birch sap or fermented birch sap. In particular, the yield of the bio-cellulose dry film obtained from the fermentation broth containing 45% of the fermented birch sap reached 4.3 g / L (Example 2, Instance 2), which is far better than the yield of 1.5 g / L obtained from the fermentation broth containing only coconut water (Example 2, Instance 6).

[0074] Example 4: Efficacy test of the biofiber facial mask cloth

[0075] In this example, the following efficacy of the prepared biofiber facial mask cloth was further investigated.

[0076] In the test, Sample 1 was the biofiber mask cloth of Example 2 in Example 1 (i.e., the biofiber mask cloth obtained by fermenting with a fermentation broth containing 45% birch sap), Sample 2 was an ordinary tencel mask cloth (purchased from Shanghai Mianfu Biotechnology Co., Ltd.), and Sample 3 was the biofiber mask cloth of Example 6 in Example 1 (i.e., the biofiber mask cloth obtained by fermenting with a fermentation broth containing only coconut juice and no birch sap).

[0077] In this test, the formula of the mask liquid used was as follows:

[0078] Table 6

[0079] Serial number Raw material name wt% 1 Deionized water Balance to 100% 2 Glycerol 3 3 Butylene glycol 3 4 Allantoin 0.1 5 Xanthan gum 0.05 6 Carbomer 0.12 7 D-panthenol 0.3 8 Betaine 2 9 Sodium hyaluronate 0.05 10 Hexylene glycol 0.5 11 p-Hydroxyacetophenone 0.5 12 Tromethamine 0.08 13 Carnosine 0.2 14 Oat kernel extract 1

[0080] 1. Test the promoting penetration effect

[0081] This test was conducted on 3 subjects. On the day of the test, the subjects washed the inner sides of both forearms with clear water and balanced for 20 min in a laboratory with constant temperature and humidity. Then, 3 test areas (area: 4x4 cm 2 ) were marked on the inner sides of both forearms of the subjects. The technician applied the sample on the test area and removed it after 30 minutes. Before the use of the sample (initial value) and 1 hour after a single use, the content of cosmetic ingredients in the test area was tested. The instrument used was a skin component analyzer (gen2-SCA, RiverD, Netherlands). Before the test, the test area was wiped 3 times with dust-free paper to wipe off the residue of the sample on the skin surface.

[0082] The results are shown in the appendix Figure 1 and 2 as follows. The results showed that 1 hour after a single use of the sample, the content of the active ingredient carnosine within 0 - 20 μm in the test area caused by Sample 1 was higher than that of Sample 2 and Sample 3. Among them, the penetration amount value of carnosine caused by Sample 1 was 4.00 times that of Sample 2 and 2.52 times that of Sample 3.

[0083] 2. Test the effect of improving skin firmness

[0084] In this test, based on a full-face design, 33 eligible female volunteers participated. During the test, the volunteers could continue to use their original skin care products and maintain their skin care habits unchanged, and use the test sample to replace the mask products they originally used, using the test sample once every other night for 4 consecutive weeks. Before using the test sample and 4 weeks after using it, a skin sagging image test was conducted on a random side of the mandibular area of the volunteers. The instrument used was a skin rapid optical imaging system (AEVA HE, Breuckmann, Germany).

[0085] The results are shown in the appendix Figure 3As shown. The results show that, when using the same facial mask liquid, Sample 1 has a more obvious improvement in skin firmness, while Sample 3 has only a slight improvement.

[0086] The technical solutions of the above embodiments are the preferred embodiments of the present invention. Without departing from the principle of the present invention, several improvements and transformations can be made, and these improvements and changes should also be regarded as within the protection scope of the present invention.

Claims

1. A method for preparing a biological fiber facial mask cloth, comprising the following steps: (1) Activating and subculturing Acetobacter xylinum to obtain a subcultured Acetobacter xylinum culture solution; (2) Uniformly inoculating 1-15% of the subcultured Acetobacter xylinum culture solution into a culture medium and performing fermentation culture at a temperature of 25-35°C for 2-5 days, wherein the culture medium contains 45-89% of birch sap and 0-44% of coconut water, and all the above content percentages are based on the total weight of the Acetobacter xylinum culture solution and the culture medium; and (3) Collecting the film; Wherein the biological fiber facial mask fabric has an average thickness of 3.0 - 6.0 mm, a wet weight of 550 - 900 g / L, and a tensile strength of 0.9 - 4.5 N / mm 2 .

2. The method according to claim 1, wherein the culture medium does not contain coconut water.

3. The method according to any one of claims 1-2, wherein 5-10% of the subcultured Acetobacter xylinum culture solution is uniformly inoculated into the culture medium.

4. The method according to any one of claims 1-2, wherein the fermentation culture is carried out at a temperature of 25-30°C for 2-3 days.

5. The method according to any one of claims 1-2, wherein the birch sap is raw birch sap, fermented birch sap, or concentrated birch sap with a concentration multiple of 1.05-10.0 times.

6. The method according to claim 5, wherein the concentration multiple of the concentrated birch sap is 2.0-6.0 times.

7. The method according to claim 5, wherein the fermented birch sap is birch sap fermented by Inonotus obliquus or birch sap fermented by yeast.

8. The method according to any one of claims 1-2, wherein the culture medium further contains a carbon source, inorganic salts, and / or a pH regulator.

9. A biological fiber facial mask cloth obtained by the method according to any one of claims 1-8.

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