A method for preparing high-activity beta-glucan

Abstract

The present application relates to the technical field of microbial fermentation, and in particular to a preparation method of high-activity beta-glucan. The preparation method comprises the following steps: selecting well-grown Saccharomyces cerevisiae MF-001 to activate the strain, further expanding and culturing the activated bacterial liquid to obtain a seed liquid, and finally inoculating the seed liquid into a fermentation medium to obtain a fermentation liquid. The fermentation medium contains 5-6% chayote extract, 1-3% tremella fruiting body extract, 0.01-0.02% tea polyphenol, 1-10% carbon source and 1-10% nitrogen source. The beta-glucan prepared by the preparation method has high yield, and the fermentation liquid is low in impurities, transparent, low in viscosity, good in flowability, and the purified beta-glucan is high in purity and good in activity.

Description

Technical Field

[0001] This invention relates to the field of microbial fermentation technology, and more specifically, to a method for preparing highly active β-glucan. Background Technology

[0002] β-glucan is a natural polysaccharide with significant immunomodulatory, antioxidant, and antitumor activities. Especially in *Saccharomyces cerevisiae*, β-glucan derived from its cell wall has become an important raw material in functional foods and pharmaceuticals due to its high safety and well-defined functions. With the increasing market demand for β-glucan, how to achieve its efficient synthesis through bio-fermentation technology has become a research hotspot in industry.

[0003] In previous studies, the applicant screened and isolated a high-β-glucan-producing *Saccharomyces cerevisiae* strain, which possesses the advantage of naturally high β-glucan production. However, during industrial fermentation, it was found that the β-glucan yield still struggled to exceed the theoretical maximum when using traditional carbon-nitrogen source media (such as glucose-yeast extract systems). Further analysis revealed limitations of traditional media, including insufficient synergistic effects between carbon and nitrogen sources, inhibition of metabolic byproducts, and nutrient imbalances.

[0004] Therefore, developing a method for preparing highly active β-glucan, wherein the present invention scientifically proportions carbon source, nitrogen source and promoter in fermentation medium to synergistically enhance the β-glucan synthesis metabolic pathway, reduce by-product inhibition and optimize product secretion, becomes the core requirement for breaking through the limitations of existing technology and achieving low-cost and high-efficiency production. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a method for preparing high-purity and high-activity β-glucan. The β-glucan obtained by this method has a high yield, and the fermentation broth has few impurities, is transparent, has low viscosity and good fluidity. Moreover, the β-glucan obtained after purification has high purity and good activity.

[0006] To achieve the above objectives, the present invention discloses the following technical solutions: In a first aspect, the present invention provides a method for preparing highly active β-glucan, wherein the fermentation method includes the following steps: 1-1. Seed activation: Select single colonies of well-grown Saccharomyces cerevisiae MF-001, inoculate them into YEPD liquid medium, and culture them in a constant temperature shaker at 28℃ and 200r / min for 20h to obtain activated bacterial solution; 1-2. Seed culture: The activated bacterial solution was inoculated into a 500 mL shake flask containing 200 mL of seed culture medium at an inoculation rate of 1 v / v%, and cultured at 28 °C and 200 r / min for 20 h to obtain the seed culture. 1-3. Fermentation culture: Inoculate the seed culture into the fermentation medium at an inoculation rate of 10 v / v%. Ferment at a speed of 150-200 r / min, a fermentation temperature of 28℃, dissolved oxygen at 20-22%, and pH at around 4.5 for 48 h to obtain the fermentation broth. 1-4. Purification: Centrifuge the fermentation broth at 8000g for 10 min, collect the supernatant, concentrate and freeze-dry to obtain highly active β-glucan.

[0007] The fermentation medium described in steps 1-3 contains the following components: 5-6% chayote extract, 1-3% tremella fruiting body extract, 0.01-0.02% tea polyphenols, 1-10% carbon source, and 1-10% nitrogen source.

[0008] Preferably, the carbon source is selected from at least one of beet juice, sugarcane juice, glucose, fructose, sucrose, maltose, and starch.

[0009] Preferably, the nitrogen source is selected from at least one of yeast extract, peptone, soybean meal, corn flour, and corn steep liquor.

[0010] Preferably, the preparation method of the chayote extract includes the following steps: 2-1. Chop the chayote fruit and dry it at 50-60℃ to constant weight, then grind and sieve it to obtain chayote powder; 2-2. Mix chayote powder with 70-80 v / v% ethanol aqueous solution at a mass-to-volume ratio of 1:(10-15) g / mL. Soak and extract with ultrasound at a water bath temperature of 60-70℃ and an ultrasonic frequency of 20-30kHz for 0.5-1h. After stopping the ultrasound, maintain the mixture in a water bath at 60-70℃ and soak while stirring for 12-16h. After soaking, centrifuge to separate the supernatant and concentrate the supernatant under reduced pressure until there is no alcohol odor to obtain the concentrated solution. 2-3. Take a certain amount of maltodextrin and dissolve it in the concentrate obtained in step 2-2. The amount of maltodextrin added is 10-15% of the mass of the concentrate. Then spray dry it. The spray drying conditions are an inlet air temperature of 150-170℃ and an outlet air temperature of 70-80℃ to obtain chayote extract.

[0011] Preferably, the preparation method of the Tremella fuciformis fruiting body extract includes the following steps: 3-1. Dry the fruiting bodies of Tremella fuciformis at 50-60℃ to constant weight, then pulverize and sieve to obtain Tremella fuciformis fruiting body powder; 3-2. Mix the powdered fruiting body of Tremella fuciformis with deionized water at a mass-to-volume ratio of 1:(10-15) g / mL. Soak and extract the fruiting body of Tremella fuciformis at a water bath temperature of 75-85℃ and an ultrasonic frequency of 20-30kHz for 20-30 min. After stopping the ultrasonic extraction, maintain the water bath temperature of 75-85℃ and soak the fruiting body with stirring for 6-10 h. After soaking, centrifuge and collect the supernatant. 3-3. The supernatant obtained in step 3-2 is spray-dried under the following conditions: inlet air temperature of 150-170℃ and outlet air temperature of 70-80℃, to obtain the extract of Tremella fuciformis fruiting body.

[0012] More preferably, the carbon source is glucose.

[0013] More preferably, the nitrogen source is at least one of yeast extract and peptone.

[0014] Preferably, the Latin name of the brewing yeast MF-001 is... Saccharomyces cerevisiae It was deposited on January 3, 2025 at the Guangdong Provincial Center for Microbial Culture Collection, located at 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou, China, postal code 510070, with accession number GDMCC No: 65715.

[0015] Preferably, the fermentation medium also contains water.

[0016] The beneficial effects of this invention are: 1. In the method for preparing highly active β-glucan provided by the present invention, adding chayote extract, tremella fruiting body extract, and tea polyphenols to a conventional fermentation medium to obtain an improved fermentation medium can effectively increase the β-glucan yield of Saccharomyces cerevisiae MF-001. Compared with the conventional fermentation medium, the β-glucan yield obtained by using the improved fermentation medium increases by 28.91%, 30.57%, and 35.23%, respectively.

[0017] 2. The yeast β-glucan prepared by this invention has high purity and good activity. In vitro experiments show that it has high antioxidant activity, reaching more than 50% of the antioxidant performance of the positive control group.

[0018] 3. The fermentation process provided by this invention is simple, easy to operate, and the raw materials are readily available. The stability of the strains is controllable, enabling large-scale production. At the same time, the preparation method provided by this invention yields high yeast β-glucan, and the fermentation broth has the characteristics of low viscosity, no odor, and high transparency, which has the prospect of being widely used in cosmetic raw materials. Detailed Implementation

[0019] Those skilled in the art can refer to the content of this document to appropriately improve the process parameters. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in this invention.

[0020] The products and methods of the present invention have been described through preferred embodiments. Those skilled in the art will be able to make modifications or appropriate alterations and combinations to the products and methods described herein without departing from the content, spirit and scope of the present invention, so as to realize and apply the technology of the present invention.

[0021] In this invention: Unless otherwise specified, the experimental methods described in the following examples are generally performed under standard conditions or as recommended by the manufacturer.

[0022] Unless otherwise specified, all materials and reagents used are commercially available. Unless otherwise stated, substances described in this invention are calculated as percentages and parts by mass. Saccharomyces cerevisiae MF-001: Latin name Saccharomyces cerevisiae The strain was deposited on January 3, 2025, at the Guangdong Provincial Center for Microbial Culture Collection, located at 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou, China, postal code 510070, with accession number GDMCC No: 65715.

[0023] Preparation of chayote extract Step 1. Chop fresh and clean chayote fruit and dry it in an oven at 50-60℃ until constant weight. Then, pulverize it in a high-speed grinder and pass it through a ≥60 mesh sieve to obtain chayote powder. Step 2. Mix chayote powder with 70-80 v / v% ethanol aqueous solution at a mass-to-volume ratio of 1:(10-15) g / mL. Soak and extract with ultrasound at a water bath temperature of 60-70℃ and an ultrasonic frequency of 20-30kHz for 0.5-1h. After stopping the ultrasound, maintain the temperature and soak while stirring for 12-16h. After soaking, centrifuge to separate the supernatant and concentrate the supernatant under reduced pressure until there is no alcohol odor to obtain the concentrated solution. Step 3. Dissolve a certain amount of maltodextrin in the concentrate obtained in Step 2. The amount of maltodextrin added is 10-15% of the mass of the concentrate. Then spray dry it. The spray drying conditions are an inlet air temperature of 150-170℃ and an outlet air temperature of 70-80℃ to obtain chayote extract.

[0024] Preparation of Tremella fruiting body extract Step 1. Place the fresh and clean Tremella fruiting bodies in an oven at 50-60℃ and dry them to constant weight. Then, place them in a high-speed pulverizer and pulverize them. Pass them through a ≥60 mesh sieve to obtain Tremella fruiting body powder. Step 2. Mix the Tremella fruiting body powder with deionized water at a mass-to-volume ratio of 1:(10-15) g / mL. Soak and extract the mixture in a water bath at 75-85℃ and an ultrasonic frequency of 20-30kHz for 20-30 minutes. After stopping the ultrasonic treatment, maintain the temperature and soak the mixture while stirring for 6-10 hours. After soaking, centrifuge to separate the supernatant. Step 3. Spray dry the supernatant obtained in Step 2. The spray drying conditions are: inlet air temperature of 150-170℃ and outlet air temperature of 70-80℃, to obtain the Tremella fuciformis extract.

[0025] Preparation of fermentation medium to increase β-glucan yield Weigh the raw materials precisely according to the percentage of mass in Table 1, and then mix them evenly with the solvent to obtain the fermentation medium; Table 1. Percentage of raw materials for fermentation culture medium

[0026] Note: " / " in the table indicates no addition.

[0027] Example 1 1. Activation and Seed Culture 1.1 Seed activation Single colonies of well-grown Saccharomyces cerevisiae MF-001 were selected from YEPD solid plates and inoculated into 50 mL of YEPD liquid medium. The colonies were then cultured for 20 h in a constant temperature shaker at 28 °C and 200 r / min. YEPD solid medium is YEPD liquid medium with 2% agar added; YEPD liquid medium consists of 1% yeast extract, 2% glucose, 2% peptone, and sterile water.

[0028] 1.2 Seed Culture The activated bacterial solution was inoculated into a 500 mL shake flask containing 200 mL of seed culture medium at an inoculation rate of 1 v / v%, and cultured at 28 °C and 200 r / min for about 20 h to further increase the number of fungi and obtain the seed solution. The seed culture medium consisted of 1% yeast extract, 2% glucose, 2% peptone, and sterile water.

[0029] 2. Fermentation culture 2.1 Vaccination The prepared seed culture was inoculated into a 10L fermenter containing fermentation medium 1, which had been verified by microscopic examination to be free of contaminants, at an inoculation rate of 10v / v%. The total volume of the fermentation broth was 5L.

[0030] 2.2 Initial Culture Conditions Setup The initial rotation speed of the fermenter was set at 150 r / min, and then gradually increased to 200 r / min and maintained as the bacteria grew. The fermentation temperature was set at 28℃, and the initial aeration rate was 1.5 vvm. The aeration rate was then gradually increased according to the dissolved oxygen value to ensure a sufficient oxygen supply.

[0031] 2.3 Monitoring and control of dissolved oxygen and pH Use a dissolved oxygen probe to monitor the dissolved oxygen level in the tank, ensuring that the dissolved oxygen level is controlled at 20% and the pH is maintained at around 4.5.

[0032] 2.4 Obtaining the fermentation broth Fermentation broth was obtained after 48 hours of fermentation.

[0033] Example 2 1. Activation and Seed Culture 1.1 Seed activation Single colonies of well-grown Saccharomyces cerevisiae MF-001 were selected from YEPD solid plates and inoculated into 50 mL of YEPD liquid medium. The colonies were then cultured for 20 h in a constant temperature shaker at 28 °C and 200 r / min. YEPD solid medium is YEPD liquid medium with 2% agar added; YEPD liquid medium consists of 1% yeast extract, 2% glucose, 2% peptone, and sterile water.

[0034] 1.2 Seed Culture The activated bacterial solution was inoculated into a 500 mL shake flask containing 200 mL of seed culture medium at an inoculation rate of 1 v / v%, and cultured at 28 °C and 200 r / min for about 20 h to further increase the number of fungi and obtain the seed solution. The seed culture medium consisted of 1% yeast extract, 2% glucose, 2% peptone, and sterile water.

[0035] 2. Fermentation culture 2.1 Vaccination The prepared seed culture was inoculated at an inoculation rate of 10 v / v% into a 10 L fermenter containing fermentation medium 2, which had been verified by microscopic examination to be free of contaminants. The total volume of the fermentation broth was 5 L.

[0036] 2.2 Initial Culture Conditions Setup The initial rotation speed of the fermenter was set at 150 r / min, and then gradually increased to 200 r / min and maintained as the bacteria grew. The fermentation temperature was set at 28℃, and the initial aeration rate was 1.5 vvm. The aeration rate was then gradually increased according to the dissolved oxygen value to ensure a sufficient oxygen supply.

[0037] 2.3 Monitoring and control of dissolved oxygen and pH Use a dissolved oxygen probe to monitor the dissolved oxygen level in the tank, ensuring that the dissolved oxygen level is controlled at 21% and the pH is maintained at around 4.5.

[0038] 2.4 Obtaining the fermentation broth Fermentation broth was obtained after 48 hours of fermentation.

[0039] Example 3 1. Activation and Seed Culture 1.1 Seed activation Single colonies of well-grown Saccharomyces cerevisiae MF-001 were selected from YEPD solid plates and inoculated into 50 mL of YEPD liquid medium. The colonies were then cultured for 20 h in a constant temperature shaker at 28 °C and 200 r / min. YEPD solid medium is YEPD liquid medium with 2% agar added; YEPD liquid medium consists of 1% yeast extract, 2% glucose, 2% peptone, and sterile water.

[0040] 1.2 Seed Culture The activated bacterial solution was inoculated into a 500 mL shake flask containing 200 mL of seed culture medium at an inoculation rate of 1 v / v%, and cultured at 28 °C and 200 r / min for about 20 h to further increase the number of fungi and obtain the seed solution. The seed culture medium consisted of 1% yeast extract, 2% glucose, 2% peptone, and sterile water.

[0041] 2. Fermentation culture 2.1 Vaccination The prepared seed culture was inoculated at an inoculation rate of 10 v / v% into a 10 L fermenter containing fermentation medium 3, which had been verified by microscopic examination to be free of contaminants. The total volume of the fermentation broth was 5 L.

[0042] 2.2 Initial Culture Conditions Setup The initial rotation speed of the fermenter was set at 150 r / min, and then gradually increased to 200 r / min and maintained as the bacteria grew. The fermentation temperature was set at 28℃, and the initial aeration rate was 1.5 vvm. The aeration rate was then gradually increased according to the dissolved oxygen value to ensure a sufficient oxygen supply.

[0043] 2.3 Monitoring and control of dissolved oxygen and pH Use a dissolved oxygen probe to monitor the dissolved oxygen level in the tank, ensuring that the dissolved oxygen level is controlled at 22% and the pH is maintained at around 4.5.

[0044] 2.4 Obtaining the fermentation broth Fermentation broth was obtained after 48 hours of fermentation.

[0045] Comparative Example 1 The fermentation process was carried out according to Example 2, wherein fermentation medium 2 was replaced with fermentation medium 4; Comparative Example 2 The fermentation process was carried out according to Example 2, wherein fermentation medium 2 was replaced with fermentation medium 5; Comparative Example 3 The fermentation process was carried out according to Example 2, wherein fermentation medium 2 was replaced with fermentation medium 6; Comparative Example 4 The fermentation process was carried out according to Example 2, wherein fermentation medium 2 was replaced with ordinary fermentation medium.

[0046] Performance testing 1. Detection of biomass and β-glucan content in fermentation broth 1.1 Determination of fermentation broth biomass: 100 ml of fermentation broth was filtered, centrifuged and washed with deionized water at 4 °C, and the supernatant was titrated with phenol and sulfuric acid until colorless. The washed yeast cells were dried at 80 °C to constant weight and weighed using a balance. The process was repeated 3 times in parallel, and the average value was taken.

[0047] 1.2 β-glucan content in fermentation broth: Accurately weigh 100ml of fermentation broth, and then test it according to the detection method of QB / T 4572-2021 "Yeast β-glucan". Repeat the test three times in parallel and take the average value of the results.

[0048] The biomass and β-glucan content of the fermentation broth are detailed in Table 2.

[0049] 2. β-glucan enhancement rate The enhancement rate of β-glucan was calculated according to equation (1):

[0050] Where: A1—the β-glucan content detected in the fermentation broth of each group; A0 – The β-glucan content detected in the fermentation broth of Comparative Example 4.

[0051] Table 2 Results of β-glucan content and biomass detection Example 1 4112.29 575.04 28.91% Example 2 4243.92 582.46 30.57% Example 3 4510.07 603.24 35.23% Comparative Example 1 3593.41 463.28 3.86% Comparative Example 2 3654.85 481.63 7.97% Comparative Example 3 3473.14 448.11 0.46% Comparative Example 4 3469.38 446.08 / 3. Determination of β-glucan purity and detection of antioxidant activity (determination of superoxide anion scavenging capacity) 3.1 Purification and Purity Determination of β-glucan The fermentation broths prepared in Examples 1-3 were centrifuged at 8000g for 10 min, and the yeast cell precipitate and fermentation supernatant were collected. The cells were washed three times with deionized water, and the washing liquid was removed by centrifugation to obtain cell precipitates 1-3. The cell precipitates 1-3 were subjected to mechanical cell disruption, wherein the cell precipitate and deionized water were mixed at a mass-volume ratio of 1:20 g / mL during the disruption process. After disruption, the supernatant was separated by centrifugation at 10000×g. The supernatant was mixed with the fermentation supernatant obtained after centrifugation of the fermentation broth, concentrated, and freeze-dried to obtain highly active β-glucan powder.

[0052] The highly active β-glucan powder was weighed, and the yeast β-glucan content in the powder was detected using the QB / T 4572 standard method. The results showed that the purity of yeast β-glucan in the β-glucan powders obtained in Examples 1-3 was 90.6%, 91.4%, and 93.7%, respectively. Therefore, the β-glucan products prepared by this invention all achieve a purity of over 90%, indicating high purity.

[0053] 3.2 Detection of antioxidant activity of β-glucan Preparation of test solution: Take 1g of β-glucan (Examples 1-3) prepared in the above steps and dissolve it in 100ml of water to obtain test solution 1-3.

[0054] Method: Accurately pipette 1 mL of the test solution and add 4.5 mL of 50 mmol / L Tris-HCl buffer solution (pH=8.2). Mix well and incubate in a 25℃ water bath for 20 min. Remove the solution and immediately add 0.3 mL of 25 mmol / L pyrogallol solution. Shake quickly and react in a 25℃ water bath for 5 min. Then add 1 mL of 8 mmol / L HCl, mix well, and terminate the reaction. Measure the absorbance at 325 nm. Distilled water was used as a blank control instead of the test solution. A 100 μg / mL aqueous solution of vitamin C was used as a positive control instead of the test solution.

[0055] Each sample was measured in triplicate, and the average value was taken.

[0056] Calculate the clearance rate according to formula (2) and record it in Table 3 below.

[0057] Clearance rate (%) = (A0-A1) / A0×100%...........(2) In the formula: A0 is the average absorbance of the blank; A1 is the average absorbance of the test liquid.

[0058] Table 3 Antioxidant Activity Test Positive control 99.58 Test solution (Example 1) 51.04 Test solution (Example 2) 52.11 Test solution (Example 3) 55.62 The results show that: According to the test results in Table 2, the production-promoting components provided by this invention can effectively increase the β-glucan yield of Saccharomyces cerevisiae MF-001 when added to ordinary culture medium. Compared with Comparative Example 4 (ordinary fermentation medium), the β-glucan yield increase rates in Examples 1-3 reached 28.91%, 30.57%, and 35.23%, respectively. Compared to ordinary fermentation culture medium, the comparative examples showed a certain effect in promoting the production of β-glucan by Saccharomyces cerevisiae, but the effect was not as obvious as in Examples 1-3. The production-promoting components in Comparative Examples 1-3 were chayote extract, Tremella fuciformis extract, and tea polyphenols, respectively. This indicates that the chayote extract, Tremella fuciformis extract, and tea polyphenols provided by this invention can effectively promote the production of β-glucan by Saccharomyces cerevisiae when used in combination.

[0059] According to the purity determination experiment and the results in Table 3, the yeast β-glucan obtained by the preparation method provided by the present invention has high purity and antioxidant activity, reaching more than 50% of the antioxidant performance of the positive control group. Vitamin C in the positive control group is recognized as one of the antioxidants with excellent antioxidant properties.

[0060] During the experiment, it was found that the fermentation product obtained by fermenting Saccharomyces cerevisiae MF-001 has the characteristics of high activity, low viscosity, high transparency and no odor. Furthermore, high-purity yeast β-glucan can be obtained through a simple subsequent purification step. Combined with the fermentation process of this invention, it can achieve large-scale production and can be widely used in the field of cosmetic raw materials.

[0061] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. A method for preparing highly active β-glucan, characterized in that, The preparation method includes the following steps: 1-1. Seed activation: Select single colonies of well-grown Saccharomyces cerevisiae MF-001, inoculate them into YEPD liquid medium, and culture them in a constant temperature shaker at 28℃ and 200r / min for 20h to obtain activated bacterial solution; 1-2. Seed culture: The activated bacterial solution was inoculated into a 500 mL shake flask containing 200 mL of seed culture medium at an inoculation rate of 1 v / v%, and cultured for 20 h at 28 °C and 200 r / min to obtain the seed culture. 1-3. Fermentation culture: Inoculate the seed culture into the fermentation medium at an inoculation rate of 10 v / v%. Ferment at a speed of 150-200 r / min, a fermentation temperature of 28℃, dissolved oxygen at 20-22%, and pH at around 4.5 for 48 h to obtain the fermentation broth. 1-4. Purification: Centrifuge the fermentation broth at 8000g for 10 min, collect the supernatant, concentrate and freeze-dry to obtain highly active β-glucan; The fermentation medium described in steps 1-3 contains the following components: 5-6% chayote extract, 1-3% tremella fruiting body extract, 0.01-0.02% tea polyphenols, 1-10% carbon source, and 1-10% nitrogen source; The preparation method of the chayote extract includes the following steps: 2-1. Chop the chayote fruit and dry it at 50-60℃ to constant weight, then grind and sieve it to obtain chayote powder; 2-2. Mix chayote powder with 70-80 v / v% ethanol aqueous solution at a mass-to-volume ratio of 1:(10-15) g / mL. Soak and extract with ultrasound at a water bath temperature of 60-70℃ and an ultrasonic frequency of 20-30kHz for 0.5-1h. After stopping the ultrasound, maintain the mixture in a water bath at 60-70℃ and soak while stirring for 12-16h. After soaking, centrifuge to separate the supernatant and concentrate the supernatant under reduced pressure until there is no alcohol odor to obtain the concentrated solution. 2-3. Take a certain amount of maltodextrin and dissolve it in the concentrate obtained in step 2-2. The amount of maltodextrin added is 10-15% of the mass of the concentrate. Then spray dry it. The spray drying conditions are an inlet air temperature of 150-170℃ and an outlet air temperature of 70-80℃ to obtain chayote extract. The preparation method of the Tremella fuciformis fruiting body extract includes the following steps: 3-1. Dry the fruiting bodies of Tremella fuciformis at 50-60℃ to constant weight, then pulverize and sieve to obtain Tremella fuciformis fruiting body powder; 3-2. Mix the fruiting body powder of Tremella fuciformis with deionized water at a mass-to-volume ratio of 1:(10-15) g / mL. Soak and extract the powder in a water bath at 75-85℃ and an ultrasonic frequency of 20-30kHz for 20-30 minutes. After stopping the ultrasonic treatment, maintain the water bath temperature at 75-85℃ and soak the powder while stirring for 6-10 hours. After soaking, centrifuge and collect the supernatant. 3-3. The supernatant obtained in step 3-2 is spray-dried under the following conditions: inlet air temperature of 150-170℃ and outlet air temperature of 70-80℃, to obtain Tremella fuciformis extract. The Latin name of the brewing yeast MF-001 is Saccharomyces cerevisiae. It was deposited on January 3, 2025 at the Guangdong Provincial Center for Microbial Culture Collection, located at 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou, China, postal code 510070, with accession number GDMCC No: 65715.

2. The preparation method according to claim 1, characterized in that, The carbon source is selected from at least one of beet juice, sugarcane juice, glucose, fructose, sucrose, maltose, and starch.

3. The preparation method according to claim 1, characterized in that, The nitrogen source is selected from at least one of yeast extract, peptone, soybean meal, corn flour, and corn steep liquor.

4. The preparation method according to claim 2, characterized in that, The carbon source is glucose.

5. The preparation method according to claim 3, characterized in that, The nitrogen source is at least one of yeast extract and peptone.

6. The preparation method according to claim 1, characterized in that, The fermentation medium also contains water.

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