A soluble fermentation medium for Wuyimycin and fermentation method thereof

Abstract

The present invention discloses a soluble fermentation medium for Wuyi mycin and a fermentation method thereof. The present invention provides a soluble fermentation medium for producing Wuyi mycin, the solvent is water, and the solute and concentration are as follows: glucose 35-40g / L, yeast powder 5g / L, peptone 5g / L, magnesium sulfate 0.5g / L, potassium chloride 0.5g / L, ferrous sulfate 0.01g / L, manganese sulfate 0.01g / L, glutamine 1g / L, aspartic acid 1g / L, sodium dihydrogen phosphate 0.38g / L, sodium hydrogen phosphate 1.19g / L, pH 7.0-7.5. The culture medium components used in the present invention are all soluble, which solves the problems of many solids, large viscosity, difficult post-processing and high cost in the existing culture medium, and the antibacterial activity of the fermentation medium after optimization is significantly enhanced compared with the original fermentation medium, and it is inferred from the chromatogram that new active substances appear.

Description

Technical Field

[0001] The invention relates to the field of biotechnology, and in particular to a wuyinomycin soluble fermentation medium and a fermentation method thereof. Background Art

[0002] Wuyimycin is a new type of agricultural antibiotic with low toxicity, high efficiency, broad spectrum and environmental protection, which has completely independent intellectual property rights in my country. It is produced by fermentation of the non-hygroscopic Streptomyces Wuyi variant. It has obvious prevention and control effects on fungal diseases of various crops such as vegetables and fruit trees. It has been widely used in agricultural production and has created considerable economic, social and ecological benefits. At present, most of the Wuyimycin on the market are 2% aqueous solutions. Although they are easy to use, they are subject to certain restrictions in packaging, storage and transportation. The active ingredients of soluble powders can be quickly dispersed and completely dissolved in water, and they have good chemical stability during storage. The processing, packaging and storage costs are relatively low. Therefore, they can give full play to their efficacy compared with wettable powders, suspensions and even emulsifiable concentrates. In addition, this dosage form does not contain organic solvents, and will not cause phytotoxicity to crops or environmental pollution due to solvents, so it is relatively safe to use.

[0003] The usual method for preparing wuyijincin soluble powder is spray condensation molding, but the existing wuyijincin fermentation medium contains insoluble components, so when preparing wettable powder, the fermentation liquid needs to be centrifuged to remove the insoluble components, and the nozzle is easily blocked when spraying. Considering the complexity, economy and safety of the process in the entire production process, it is necessary to develop a soluble wuyijincin fermentation medium to reduce production costs and improve ease of use, so as to solve the problems of high solids, high viscosity, difficult post-processing and high cost in the existing culture medium. Summary of the invention

[0004] The purpose of the present invention is to provide a wuyimycin soluble fermentation medium and a fermentation method thereof.

[0005] In a first aspect, the present invention claims a soluble fermentation medium for producing wuyimycin.

[0006] The solvent of the fermentation medium claimed in the present invention is water, and the solutes and concentrations are as follows: glucose 35-40 g / L (such as 40 g / L), yeast powder 5 g / L, peptone 5 g / L, magnesium sulfate 0.5 g / L, potassium chloride 0.5 g / L, ferrous sulfate 0.01 g / L, manganese sulfate 0.01 g / L, glutamine 1 g / L, aspartic acid 1 g / L, sodium dihydrogen phosphate 0.38 g / L, sodium hydrogen phosphate 1.19 g / L, and the pH is adjusted to 7.0-7.5 (such as pH 7.5) with aqueous ammonia.

[0007] In a second aspect, the present invention claims the use of the fermentation medium described in the first aspect above in fermenting and culturing a wuyimycin-producing strain to prepare wuyimycin.

[0008] In a third aspect, the present invention claims protection for the use of the fermentation medium described in the first aspect above in fermenting and culturing a wuyimycin-producing strain to prepare a wuyimycin soluble powder.

[0009] In a fourth aspect, the present invention claims a method for preparing wuyimycin.

[0010] The method for preparing wuyimycin claimed in the present invention may include the following steps: inoculating the wuyimycin-producing strain into the fermentation medium described in the first aspect above for culturing.

[0011] Furthermore, the culture temperature may be 28-30°C (such as 30°C).

[0012] Furthermore, the culturing time may be 48-96 hours.

[0013] Furthermore, during the culture process, the pH of the fermentation system can be controlled to be 6.0-7.0.

[0014] Furthermore, the culture may be cultured on a shaking table at 200-220 rpm (such as 220 rpm).

[0015] Furthermore, the inoculation time of the wuyimycin production strain inoculated into the fermentation medium for culturing is 30 hours after the wuyimycin production strain is inoculated into the seed medium shake flask culture. The solvent of the seed medium is water, and the solute and concentration are: glucose 20g / L, peptone 6g / L, yeast powder 6g / L, sodium chloride 10g / L. In a specific embodiment of the present invention, the inoculation amount is 2% (volume percentage).

[0016] In a fifth aspect, the present invention claims protection for a set of products for preparing Wuyimycin.

[0017] The complete set of products for preparing wuyimycin claimed in the present invention consists of the fermentation medium and wuyimycin-producing strain described in the first aspect above.

[0018] In a sixth aspect, the present invention claims a fermentation broth.

[0019] The fermentation broth claimed in the present invention is obtained by inoculating the wuyimycin-producing strain into the fermentation medium described in the first aspect above for culturing.

[0020] Furthermore, the culture temperature may be 28-30°C (such as 30°C).

[0021] Furthermore, the culturing time may be 48-96 hours.

[0022] Furthermore, during the culture process, the pH of the fermentation system can be controlled to be 6.0-7.0.

[0023] Furthermore, the culture may be cultured on a shaking table at 200-220 rpm (such as 220 rpm).

[0024] Furthermore, the inoculation time of the wuyimycin production strain inoculated into the fermentation medium for culturing is 30 hours after the wuyimycin production strain is inoculated into the seed medium shake flask culture. The solvent of the seed medium is water, and the solute and concentration are: glucose 20g / L, peptone 6g / L, yeast powder 6g / L, sodium chloride 10g / L. In a specific embodiment of the present invention, the inoculation amount is 2% (volume percentage).

[0025] In a seventh aspect, the present invention claims the use of the fermentation broth in any of the following:

[0026] (A1) Antibacterial;

[0027] (A2) Prepare a product with antibacterial activity.

[0028] Furthermore, the bacteria are fungi.

[0029] In a specific embodiment of the present invention, the antibacterial agent is the inhibition of red yeast.

[0030] In a specific embodiment of the present invention, the wuyienin producing strain is Streptomyces albulus var. wuyiensis CK-15.

[0031] The culture medium components used in the present invention are all soluble, which solves the problems of high solid content, high viscosity, difficult post-processing and high cost in the existing culture medium. The antibacterial activity of the optimized fermentation medium is significantly enhanced compared with the original fermentation medium, and it is inferred from the chromatogram that new active substances appear. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The biomass change of strain CK-15 in Example 1 during the fermentation process.

[0033] Figure 2 The change of glucose content in the fermentation liquid during the fermentation process in Example 1.

[0034] Figure 3 The pH value of the fermentation liquid in Example 1 changes during the fermentation process.

[0035] Figure 4The following are the changes in various indicators of the seed liquid during the fermentation process of strain CK-15 in Example 2.

[0036] Figure 5 This is the growth curve of the seed solution of strain CK-15 in Example 3.

[0037] Figure 6 The antibacterial activity of the fermentation broth at different fermentation times in Example 4.

[0038] Figure 7 It is the diameter of the inhibition zone of the fermentation liquid at different fermentation times in Example 4.

[0039] Figure 8 The antibacterial activity of the fermentation broth at different fermentation times in Example 5.

[0040] Fig. 9 The antibacterial activity of the optimized fermentation broth and the original fermentation broth containing the same amount of wuyimycin in Example 5 is compared. The left side shows the antibacterial activity of the original fermentation broth, and the right side shows the antibacterial activity of the optimized fermentation broth. The titer of wuyimycin is 1800 ppm.

[0041] Fig.10 This is the HPLC detection chromatogram of the original fermentation broth (insoluble culture medium) in Example 5.

[0042] Fig.11 This is the HPLC detection chromatogram of the optimized fermentation broth (glucose content 40 g / L) in Example 5. DETAILED DESCRIPTION

[0043] The present invention is further described in detail below in conjunction with specific embodiments, and the examples provided are only for illustrating the present invention, rather than for limiting the scope of the present invention. The examples provided below can be used as a guide for further improvements by those of ordinary skill in the art, and do not constitute a limitation of the present invention in any way.

[0044] The experimental methods in the following examples, unless otherwise specified, are all conventional methods, and are performed according to the techniques or conditions described in the literature in the field or according to the product instructions. The materials, reagents, etc. used in the following examples, unless otherwise specified, can all be obtained from commercial channels.

[0045] Example 1: Screening of the highest temperature resistant strains of wuyimycin production

[0046] 1. Test strains

[0047] S.albulus var.wuyiensis CK-15, from the Agricultural Antibiotics Research Group of the Institute of Plant Protection, Chinese Academy of Agricultural Sciences. Recorded in the article "Lv Z, Lu Y, Li B, et al. Effects of ε-Poly-L-Lysine Combined with Wuyiencin as a Bio-Fungicide against Botryris cinerea[J]. Microorganisms, 2022, 10(5): 971."

[0048] 2. Test culture medium

[0049] MS culture medium: Boil 20g soybean flour in distilled water for 30min, filter the mixture with 4 layers of gauze to make up to 1000mL, and dispense 100mL of the mixture into a 250mL Erlenmeyer flask containing 2.0g mannitol and 1.7g agar powder. Sterilize the mixture by wet heat at 121℃ for 30min.

[0050] Seed culture medium: The solvent is water, and the solutes and concentrations are as follows: glucose 20 g / L, peptone 6 g / L, yeast powder 6 g / L, and sodium chloride 10 g / L.

[0051] 3. Detection of relevant indicators during fermentation

[0052] CK-15 was cultured at 28°C in MS medium. After 5-7 days of culture, fresh mature spores were inoculated into 100 mL seed medium and cultured with shaking (28°C, 220 r / min) for 24 hours. Then, the seed solution was inoculated into 100 mL seed medium at a 2% (volume percentage) inoculation amount, and shake flask culture was performed at 28°C, 35°C and 40°C, and 3 bottles of seed solution were taken from the shaker at 28°C, 35°C and 40°C every 12 hours. The pH of each bottle of seed solution was measured with a pH meter, and the glucose content in the sample was measured with a glucose detection kit (AKSU001M). The morphological changes of the strain at different times were observed with an optical microscope. At the same time, 50 mL of fermentation liquid was taken from each bottle of sample and filtered with filter paper to keep the mycelium on the filter paper. The mycelium dry weight was measured after drying in a 90°C constant temperature drying oven to constant weight.

[0053] The results showed that the biomass of strain CK-15 was the highest at 28℃, and the lowest at 40℃ with no change ( Figure 1 ). As the fermentation time increases, the glucose concentration in the culture medium at 28°C and 35°C gradually decreases. There is no significant change in the glucose concentration in the culture medium at 40°C ( Figure 2). The pH of the fermentation liquid varied between 5.0 and 6.5, and showed a gradual downward trend during the fermentation process. The pH of the strain showed the same trend at 28°C and 35°C, and there was no significant change at 40°C ( Figure 3 ). The biomass showed a gradual upward trend. However, there was no significant change in biomass at 40°C, which proved that the mycelium could not grow and reproduce normally at this temperature, but could grow and reproduce normally at 28°C-35°C. Therefore, the strain could tolerate a maximum temperature range of 28°C-35°C.

[0054] Example 2: Screening of the optimum temperature of strain CK-15

[0055] In Example 1, it was found that the strain CK-15 can withstand a maximum temperature range of 28°C-35°C. In order to clarify the optimum growth temperature of strain CK-15, the shake flask fermentation temperature was adjusted to 28°C, 30°C, and 33°C. The biomass, pH, Wuyijinsu titer (content) and glucose concentration were sampled every 12h, and the bacterial morphology was observed under a microscope. The fermentation and sampling detection methods were consistent with the relevant methods in Example 1. The determination method of the Wuyijinsu titer (content) of the fermentation broth is as follows: 2mL of the fermentation broth was taken, centrifuged at 12000rpm for 5min, and the supernatant was passed through a 0.22μm organic filter membrane. The Wuyijinsu standard was prepared into 1000μg / mL with distilled water, and the standard was used as a control. The response peak area of ​​the sample Wuyijinsu calculated by the liquid chromatograph analysis software was compared with the standard to obtain the content of Wuyijinsu in the fermentation broth. HPLC conditions are as follows: Mobile phase: 1.4 g TCA is dissolved in 1 L ultrapure water to prepare TCA solution, and the TCA solution and methanol are ultrasonically degassed for 30 min. Liquid chromatography conditions: The chromatographic column is a C18 column (150×4.6 mm), the column temperature is 40°C, the flow rate is 1 mL / min, the injection volume is 10 μL, the chromatographic retention time is 25 min, and the ultraviolet detection wavelength is 456 nm.

[0056] The results show that ( Figure 4 ), strain CK-15 had the largest biomass at 30℃, consumed the most glucose during fermentation, and was able to produce wuyinomycin normally during this period, so the optimal growth temperature of strain CK-15 was determined to be 30℃.

[0057] Example 3. Preparation of seed growth curve of strain CK-15

[0058] Use MS medium to culture strain CK-15 at 30℃. After 5-7 days of culture, take fresh mature spores and inoculate them into 100mL seed medium for shaking culture (30℃, 220r / min) for 24h. Then inoculate the seed liquid into 100mL seed medium at a 2% (volume percentage) inoculation amount, and perform shake flask culture at 30℃ and 220r / min. Take 3 bottles from the shaker every 2h, take 5mL of seed liquid and place them in 10mL centrifuge tubes to check their biomass. Take 3mL of seed liquid from the centrifuge tube into a quartz cuvette, and measure the initial OD in a spectrophotometer. 600 Dilute the sample to OD 600 The value is between 0.2 and 0.8. Take 200 μL of the diluted sample and add it to a 96-well plate. Repeat three times for each bottle of sample and measure the OD in an enzyme reader. 600 value, and then use the measured OD 600 The value is multiplied by the dilution factor to obtain the OD of each stock solution. 600 value.

[0059] Test results ( Figure 5 ) showed that 0-3h was the growth retardation period of the strain, 3-30h was the logarithmic growth period of the strain, and it entered the stable period after 30h. The optimal inoculation time was determined to be 30h after the seed liquid was shaken in a flask.

[0060] Example 4: Optimization of soluble fermentation medium

[0061] 1. Test culture medium

[0062] Based on the preliminary laboratory research, according to the composition and strain characteristics of the original wuyimycin fermentation medium, this experiment further provides a new soluble fermentation medium based on the original insoluble wuyimycin fermentation medium. The fermentation medium consists of: 20g / L glucose, 5g / L yeast powder, 5g / L peptone, 0.5g / L magnesium sulfate, 0.5g / L potassium chloride, 0.01g / L ferrous sulfate, 0.01g / L manganese sulfate, 1g / L glutamine, 1g / L aspartic acid, 0.38g / L sodium dihydrogen phosphate, 1.19g / L sodium hydrogen phosphate, and the pH is adjusted to 7.5 with ammonia water.

[0063] 2. Preparation of Seed Solution

[0064] CK-15 was cultured at 28°C using MS medium. After 5-7 days of culture, the cake was cut into 1 cm blocks. Fresh mature spores were inoculated into 100 mL seed medium and cultured with shaking (30°C, 220 r / min) for 30 h.

[0065] The MS culture medium is composed of: boiling 20g soybean flour in distilled water for 30min, filtering with 4 layers of gauze to a constant volume of 1000mL, and each 100mL is filled into a 250mL conical flask containing 2.0g mannitol and 1.7g agar powder, and sterilizing with high temperature and wet heat at 121°C for 30min.

[0066] Seed culture medium: The solvent is water, and the solutes and concentrations are as follows: glucose 20 g / L, peptone 6 g / L, yeast powder 6 g / L, and sodium chloride 10 g / L.

[0067] 3. Fermentation

[0068] The seed solution prepared above was inoculated into a 250 mL Erlenmeyer flask containing 100 mL of fermentation medium (see step 1 for the formula) at 2% (volume percentage), and cultured in a shaking incubator at 30°C and 220 rpm. Samples were taken every 12 hours, and three parallels were set for each sample. After sampling, the biomass, wuyi mycin content, glucose content, pH in the fermentation broth were detected, and the antibacterial activity was determined.

[0069] 4. Sample Testing

[0070] The samples were centrifuged to obtain fermentation broth, and the pH of each sample was tested using a pH meter. 600 The sample biomass was calculated by the value, and the optimal dilution multiple of each sample was tested under the spectrophotometer (the value measured under the spectrophotometer should be within 0.5-0.8), 3mL of each diluted solution was placed in a cuvette, and the wavelength was measured at 600nm under the spectrophotometer. The potency of Wuyi mycin in the fermentation broth was analyzed and detected by high performance liquid chromatography. Chromatographic conditions: the chromatographic column was ZORBAX SB-AQ (4.6nm×250mm, 5μm); the mobile phase was 1.4g / L trichloroacetic acid aqueous solution, the flow rate was 1mL / min; the column temperature was 40℃; the injection volume was 10μL; the detection wavelength was 254nm. A glucose kit (AKSU001M) was used to detect the glucose content in the fermentation broth. The fermentation broth sample was diluted 20 times, and 20 μL of the diluted supernatant was placed in a 96-well plate containing 180 μL of glucose oxidoreductase solution. The plate was placed in a microplate reader and incubated at 37°C with sufficient shaking for 15 minutes. The absorbance value (A505) was then measured at 505 nm. Finally, the amount of residual glucose was determined based on the glucose standard curve.

[0071] The results show (Table 1) that the pH of the fermentation broth showed a trend of first decreasing and then increasing during the fermentation process. The glucose content in the fermentation broth dropped sharply in the first 48 hours, and the glucose in the fermentation broth was completely consumed at 60 hours. The biomass gradually increased within 48 hours, and the biomass reached the maximum value at 60 hours, which was consistent with the change trend of glucose, proving that the strain consumed a large amount of glucose before 60 hours for its growth and reproduction, and after 60 hours, all the glucose was consumed and the biomass no longer increased. After 24 hours of fermentation, the strain began to produce Wuyi mycin, which gradually increased and stabilized after 72 hours.

[0072] Table 1. Changes of indicators in the fermentation liquid during the fermentation process

[0073]

[0074]

[0075] 5. Determination of antibacterial activity

[0076] The wuyimycin fermentation broth obtained by fermentation was passed through a 0.22 μm microporous filter to obtain a sterile fermentation broth. The antibacterial activity of the fermentation broth was determined by the tube-plate method using the model fungal strain red yeast as an indicator bacteria. An Oxford cup was placed on a PDA culture medium containing red yeast, 200 μL was injected into the Oxford cup, and the cup was placed in a constant temperature incubator at 25°C for static culture. The size of the inhibition zone was observed and measured at 12h, 24h, 36h, 48h, 60h, 72h, 84h, 96h, 108h, and 120h of culture, respectively, to obtain the antibacterial activity of the strain fermentation broth.

[0077] Test results: The fermentation liquid began to produce an inhibition zone at 24 hours, and the inhibition zone gradually increased with the increase of fermentation time. The bacterial activity did not change significantly after 72 hours. Figure 6 , Figure 7 ).

[0078] Example 5: Effect of increasing glucose content on the antibacterial activity of fermentation broth

[0079] In Example 4, it was found that the glucose content (20 g / L) in the soluble fermentation medium was low and was consumed only at 60 h of fermentation. Therefore, in order to allow the strain to have sufficient carbon source to produce more active substances during the fermentation process, the glucose content was increased to 40 g / L, and the pH was controlled between 6.0 and 7.0 with ammonia water during the fermentation process, and sampling and testing were performed. The fermentation and sampling and testing methods were consistent with those in Example 4.

[0080] The solvent of the fermentation medium is water, and the solutes and concentrations are as follows: 40 g / L glucose, 5 g / L yeast powder, 5 g / L peptone, 0.5 g / L magnesium sulfate, 0.5 g / L potassium chloride, 0.01 g / L ferrous sulfate, 0.01 g / L manganese sulfate, 1 g / L glutamine, 1 g / L aspartic acid, 0.38 g / L sodium dihydrogen phosphate, 1.19 g / L sodium hydrogen phosphate, and the pH is adjusted to 7.5 with aqueous ammonia.

[0081] Test results: The physiological metabolism of strain CK-15 was vigorous during the fermentation process. According to the biomass (Table 2), the strain grew and multiplied in large quantities in the first 48 hours, then grew slowly and gradually stabilized. The fermentation liquid began to produce an inhibition zone at 36 hours, and the inhibition zone gradually increased with the increase of fermentation time ( Figure 8 ), compared with the fermentation medium with 20 g / L glucose, the antibacterial activity of the fermentation medium with 40 g / L glucose was significantly increased. And the optimized medium can still produce good antibacterial activity when the content of wuyimycin is low, among which the optimized medium (i.e. the fermentation medium with 40 g / L glucose added in this embodiment) has much higher antibacterial activity than the original medium with 1800 ppm wuyimycin content (original insoluble wuyimycin fermentation medium: 30 g / L corn flour, 20 g / L soybean cake powder, 20 g / L glucose, 4 g / L ammonium sulfate, 3 g / L calcium carbonate) ( Fig. 9 ). Comparison of the liquid chromatograms of the fermentation broth before and after optimization ( Fig.10 , Fig.11 ), it was found that in addition to wuyimycin, new peaks appeared in the optimized chromatogram (see Fig.11 Therefore, it is speculated that new active substances may appear in the optimized fermentation broth, and have higher antibacterial activity.

[0082] Table 2. Changes of various indicators in the fermentation liquid during the fermentation process

[0083]

[0084] The present invention has been described in detail above. It will be apparent to those skilled in the art that the present invention may be implemented in a wide range under equivalent parameters, concentrations and conditions without departing from the spirit and scope of the present invention and without the need for unnecessary experimentation. Although the present invention provides specific embodiments, it should be understood that further improvements may be made to the present invention. In short, according to the principles of the present invention, this application intends to include any changes, uses or improvements to the present invention, including changes made by conventional techniques known in the art that depart from the scope disclosed in this application. Applications of some of the basic features may be made within the scope of the following appended claims.

Claims

1. A soluble fermentation medium for Streptomyces parvum var. wuyiensis ( S.albulus var.wuyiensis) CK-15 for fermentation culture to prepare wuyienin; The solvent of the soluble fermentation medium is water, and the solutes and concentrations are as follows: 35-40 g / L glucose, 5 g / L yeast powder, 5 g / L peptone, 0.5 g / L magnesium sulfate, 0.5 g / L potassium chloride, 0.01 g / L ferrous sulfate, 0.01 g / L manganese sulfate, 1 g / L glutamine, 1 g / L aspartic acid, 0.38 g / L sodium dihydrogen phosphate, 1.19 g / L sodium hydrogen phosphate, and a pH of 7.0-7.

5.

2. Use of a soluble fermentation medium in fermenting Streptomyces parvum var. wuyi CK-15 to prepare wuyiin soluble powder; The solvent of the soluble fermentation medium is water, and the solutes and concentrations are as follows: 35-40 g / L glucose, 5 g / L yeast powder, 5 g / L peptone, 0.5 g / L magnesium sulfate, 0.5 g / L potassium chloride, 0.01 g / L ferrous sulfate, 0.01 g / L manganese sulfate, 1 g / L glutamine, 1 g / L aspartic acid, 0.38 g / L sodium dihydrogen phosphate, 1.19 g / L sodium hydrogen phosphate, and a pH of 7.0-7.

5.

3. A method for preparing wuyimycin, comprising the following steps: inoculating Streptomyces parvum var. wuyi CK-15 into a soluble fermentation medium for culturing; The solvent of the soluble fermentation medium is water, and the solutes and concentrations are as follows: 35-40 g / L glucose, 5 g / L yeast powder, 5 g / L peptone, 0.5 g / L magnesium sulfate, 0.5 g / L potassium chloride, 0.01 g / L ferrous sulfate, 0.01 g / L manganese sulfate, 1 g / L glutamine, 1 g / L aspartic acid, 0.38 g / L sodium dihydrogen phosphate, 1.19 g / L sodium hydrogen phosphate, and a pH of 7.0-7.

5.

4. The method according to claim 3, characterized in that: The culture temperature is 28-30°C; and / or The culturing time is 48-96 hours; and / or During the culture process, the pH of the fermentation system is controlled to be 6.0-7.0; and / or The culture is carried out in a shaking incubator at 200-220 rpm.

5. A complete set of products for preparing wuyijincin, consisting of a soluble fermentation medium and a wuyijincin producing strain; The solvent of the soluble fermentation medium is water, and the solutes and concentrations are as follows: 35-40 g / L glucose, 5 g / L yeast powder, 5 g / L peptone, 0.5 g / L magnesium sulfate, 0.5 g / L potassium chloride, 0.01 g / L ferrous sulfate, 0.01 g / L manganese sulfate, 1 g / L glutamine, 1 g / L aspartic acid, 0.38 g / L sodium dihydrogen phosphate, 1.19 g / L sodium hydrogen phosphate, pH 7.0-7.5; The wuyimycin production strain is Streptomyces parvum var. wuyi ( S.albulus var. wuyiensis) CK-15.

6. A fermentation broth obtained by inoculating Streptomyces parvum var. wuyi CK-15 into a soluble fermentation medium for culturing; The solvent of the soluble fermentation medium is water, and the solutes and concentrations are as follows: 35-40 g / L glucose, 5 g / L yeast powder, 5 g / L peptone, 0.5 g / L magnesium sulfate, 0.5 g / L potassium chloride, 0.01 g / L ferrous sulfate, 0.01 g / L manganese sulfate, 1 g / L glutamine, 1 g / L aspartic acid, 0.38 g / L sodium dihydrogen phosphate, 1.19 g / L sodium hydrogen phosphate, and a pH of 7.0-7.

5.

7. The fermentation broth according to claim 6, characterized in that: The culture temperature is 28-30°C; and / or The culturing time is 36-96 hours; and / or During the culture process, the pH of the fermentation system is controlled to be 6.0-7.0; and / or The culture is carried out in a shaking incubator at 200-220 rpm.

8. Use of the fermentation broth according to claim 6 or 7 in preparing a product with antibacterial activity, wherein the fungus is a fungus.

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