AU2020101570A4

AU2020101570A4 - A Method for liquid fermentation of Cordyceps militaris strain

Info

Publication number: AU2020101570A4
Application number: AU2020101570A
Authority: AU
Inventors: Jing Guo; Zhengyi Qu; Juan SONG; Shiquan Xu; Meixia YAN; Hao Zhang
Original assignee: Chinese Acad Of Agricultural Sciences
Current assignee: CHINESE ACADEMY OF AGRICULTURAL SCIENCES
Priority date: 2020-07-30
Filing date: 2020-07-30
Publication date: 2020-09-10
Anticipated expiration: 2028-07-30

Abstract

The invention provides a method for liquid fermentation of Cordyceps militaris strain, which comprises the following steps: inoculating the Cordyceps militaris strain in a liquid fermentation medium, using table concentrator to cultivate, controlling the temperature between 19-21 °C, controlling the rotating speed of the table concentrator to 200-220 rad/min, and cultivating in dark for 8-14 days; The liquid fermentation medium is prepared from fruits or roots of Araliaceae plants, which is relatively easy to obtain without the need to add other ingredients. The preparation process is simple, convenient, economical and environment friendly. The product fermented by adopting the specific culture medium not only can improve the cordycepin content, but also contains a large number of rare saponin components in the product, and provides a more novel operation route for liquid fermentation of Cordyceps militaris strains, which is worthy of vigorous popularization and application, and also fills the gaps in related technologies.

Description

AUSTRALIA

PATENTS ACT 1990

PATENT SPECIFICATION FOR THE INVENTION ENTITLED:

A Method for liquid fermentation of Cordyceps militaris strain

The invention is described in the following statement:-

A Method for liquid fermentation of Cordyceps militaris strain

TECHNICAL FIELD

[0001] The invention relates to the fermentation field of Cordyceps militaris strains, in particular to a liquid fermentation method of Cordyceps militaris strains.

BACKGROUND

[0002] Cordyceps militaris belongs to Ascomycota, ergotaceae, which is a complex composition of two parts: the underground stroma and the above ground fruiting body. Cordyceps militaris spores spread in autumn and infect the insect body, hypha grows early in the insect body, absorbing nutrition, and the larva body will be filled with hypha, and die. By the time of summer and autumn of the following year, grass bodies will grow from the larvae, and wild Cordyceps militaris can be collected around the middle of September. Cordycepin contained in Cordyceps militaris has a variety of physiological active constituent, which have curative effect such as anti-tumor, anti-virus and immunity enhancement.

[0003] In current technologies, chemical synthesis and biosynthesis are generally the two ways to obtain cordycepin. The production cost of chemical synthesis is relatively high,which synthesis process is relatively complex, and the yield is low, the purification of the product is relatively difficult. There are two ways to prepare cordycepin by biosynthesis:By solid fermentation to obtain cordyceps fruiting bodies, and then extract them; The second is to directly extract from the fermentation product through liquid fermentation of Cordyceps militaris. Due to the advantages of liquid fermentation over solid fermentation in fermentation scale, cell growth rate, growth density and controllability, extracting cordycepin from Cordyceps militaris by liquid fermentation is the main application method for preparing cordycepin at present, Moreover, the fermentation method is relatively mature, However, the content of cordycepin extracted by the current fermentation method is maintained at a stable level, and it is difficult to make any new breakthrough under the limitation of the existing process conditions. And the preparation method of the fermentation medium used is complicated and difficult to operate, which virtually increases the workload of extracting cordycepin, consumes manpower and material resources, and it is uneconomical and environmentally friendly. In view of this, the present invention is hereby proposed.

[0004] Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field.

SUMMARY

[0005] It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative.

[0006] The object of the present invention is to provide a method for liquid fermentation of a Cordyceps militaris strain, The fermented substrate mainly uses the fruit or root of Araliaceae plant as the raw material, This raw material is relatively easy to obtain without the need to add other ingredients, The preparation process is simple and convenient, The product fermented by adopting the specific culture medium can not only improves the cordycepin content, but also makes the product contain a large amount of rare saponin components, thus increasing the value of subsequent development, providing a more novel operation route for liquid fermentation of Cordyceps militaris strains, which is worthy of vigorous popularization and application, and filling in the gaps of related technologies.

[0007] In order to achieve the above object of the present invention, the following technical scheme is specially adopted:

[0008] An embodiment of the invention provides a method for liquid fermentation of Cordyceps militaris strain, which comprises the following steps: inoculating the Cordyceps militaris strain in a liquid fermentation medium, cultivating in the table concentrator, controlling the temperature between 19 and 21 °C, controlling the rotating speed of the table concentrator at 200 to 220 rad/min, and cultivating in dark for 8 to 14 days.

[0009] The liquid fermentation medium is prepared from fruits or roots of Araliaceae plants as raw materials.

[0010] In the current technologies, there are methods for liquid fermentation using Cordyceps militaris strains, However, the traditional culture method is generally a fermentation medium with glucose, peptone and yeast extract as the main components. In fact, these components can only meet the basic growth and development needs of Cordyceps militaris. The content of cordycepin is relatively low, but the invention adopts the fruit or root of the Araliaceae plant as raw material to replace glucose, peptone and yeast extract to prepare the culture medium, which is not only simple in composition and more convenient to prepare, but also more suitable for the growth and development needs of Cordyceps militaris because the Araliaceae plant is rich in various nutrient components, and increases metabolites of mycelium growth which further improves the content of cordycepin, and the product also contains rare saponins besides conventional cordycepin, which is equivalent to obtaining more valuable effective components through the special fermentation matrix of the invention, and increaseings the subsequent development value.

[0011] Of course, more preferred Araliaceae plants are ginseng fruit, ginseng root, American ginseng fruit, American ginseng root, notoginseng, Gynostemma pentaphyllum, The better ones are ginseng fruit, ginseng root, American ginseng fruit and American ginseng root, because after a large number of creative tests, the inventor found that these raw materials are not only easy to obtain, which come from a wide range of sources and are relatively cheap, but also the content of cordycepin and saponin obtained by fermentation culture is high. Therefore, it is best to select these kinds of raw materials to prepare the culture medium in the actual operation process. In the culture process, in order to match the specific culture medium type of the present invention, the culture temperature and the culture time in the specific culture process have specific requirements, the culture temperature needs to be controlled between 19-21 °C, the culture time in dark is 8-14d, table concentrator rotation speed is controlled between 200-220 rad/min, and more preferably, the culture temperature is controlled between 20-21 °C and the table concentrator rotation speed is controlled between 205-215 rad/min.

[0012] The dark culture time may vary slightly for different fermentation media. The Cordyceps militaris strain is inoculated in a liquid fermentation medium prepared by ginseng fruit and American ginseng fruit for a time of 8-10 days, and the Cordyceps militaris strain is inoculated in a liquid fermentation medium prepared by ginseng root and

American ginseng root for a time of 12-14 days. The above operating conditions are specific to the liquid fermentation process of the present invention, and it can only be adapted to the specific liquid fermentation medium of the invention. Because the inventor first selected the most suitable liquid fermentation medium, then fermented and cultured the Cordyceps militaris strain and explored the culture conditions, if the traditional culture method is adopted, the specific culture conditions may be different, and the culture operation steps may also be different.

[0013] In this invention, if the fermentation medium is prepared by using ginseng fruit and American ginseng fruit, the preparation method of the liquid fermentation medium comprises the following steps: picking fresh ginseng fruit or American ginseng fruit, squeezing and filtering the fruit to obtain fruit juice, and sterilizing at 120-125 °C for 10-20min to obtain the fruit juice.

[0014] Preferably, the sterilization temperature is controlled between 121-124. °C. and the sterilization time is 15-18min.

[0015] The whole preparation method is simple and easy to operate. It can be obtained by directly juicing fresh ginseng fruit or American ginseng fruit and sterilizing it without adding any other components, and is easy to operate. Sterilization temperature and sterilization time are best controlled to achieve ideal sterilization effect.

[0016] If the liquid fermentation medium is prepared from ginseng root and American ginseng root, the preparation method of the liquid fermentation medium comprises the following steps: cutting crushing and sieving ginseng root or American ginseng root, adding water to extract water extract, adding glucose and sterilizing.

[0017] The ginseng root or the American ginseng root is first pre treated and cut into small pieces, preferably into pieces with a particle size of 1-2cm, and more preferably into pieces with a particle size of 1.5 1.8 cm.

[0018] Preferably, the mesh size of the crushed and screened is controlled to be above 80 mesh, more preferably above 100 mesh, and the powdery root whiskers are more conducive to sufficient leaching of the active components during subsequent extraction, so it is preferable to form uniform powders to be more conducive to subsequent operation. Preferably, in the water addition extraction process, the added water amount is 30-40ml per gram of American ginseng root or ginseng root, and the water amount should not be too large or too small to achieve the extraction effect, but too large an amount will cause waste and will not further improve the extraction rate.

[0019] Preferably, the extraction time is controlled between 3-4h, more preferably between 3.5 and 3.8 h, and the effective ingredient can be substantially fully extracted by controlling the extraction time to about 3h.

[0020] Preferably, 15-20 min is centrifuged after extraction for purification, and the rate of centrifugation is controlled at 8000 10000rad/min, after centrifugation, the impurities can be separated to achieve the effect of purification.

[0021] In addition, it is preferable to sterilize at 120-125.°C. for 10 min, and more preferably the sterilization temperature is controlled at 121-124.°C.

[0022] The sterilization time is 15-18min.

[0023] In addition, other plants of Araliaceae, such as Panax notoginseng and Gynostemma pentaphyllum, can be operated according to the preparation method of liquid fermentation medium for ginseng root or American ginseng root (including ginseng main root and American ginseng main root). The preparation methods of liquid fermentation medium are similar and can be used for reference from each other.

[0024] In summary, in the process of liquid fermentation of Cordyceps militaris strain, the inventors creatively selected a special liquid fermentation medium, and abandoning the traditional culture medium. It has pioneering significance and explored a suitable operation process for Cordyceps militaris fermentation culture, including specific culture time, table concentrator rate and specific preparation process of various liquid fermentation media. These conditions were optimized, which provided reference data for subsequent implementation operation and had certain guiding significance.

[0025] Compared with the current technologies, the present invention has the advantages of:

[0026] (1) The invention adopts Cordyceps militaris strain to carry out liquid fermentation, the fermentation substrate is the fruit or root of Araliaceae plants, and the product fermented by the fermentation substrate of the invention contains rare saponins and cordycepin double effective components, and the content of cordycepin is improved compared with the previous fermentation method;

[0027] (2) The liquid fermentation of Cordyceps militaris strain mainly aims at obtaining Cordycepin. According to the invention, the effective components of other traditional Chinese medicines can be obtained through a special fermentation matrix, which provides a new idea for the combined development of Cordyceps militaris strains and other traditional Chinese medicines. The fermentation product contains dual effective components of rare saponin and cordycepin, which can obtain rare saponin monomer and cordycepin through separation and purification, and has high subsequent development value.

[0028] The fermentation method of the present invention makes good use of ginseng fruit juice, American ginseng fruit juice, as that main use of the common ginseng fruit and the American ginseng fruit is to obtain the seed, namely the ginseng seed, and the fruit juice is an additional product and has no other use, the method of the invention realizes the rational allocation of resources, improves the added value of the fruit juice, and provides a new way and a new method for the utilization of the fruit juice.

DESCRIPTION OF THE INVENTION

[0029] Preferred embodiments of the invention will now be described with reference to the accompanying drawings and non-limiting examples.

[0030] Embodiments of the invention will be described in detail below in connection with embodiments, but those skilled in the art will understand that the following embodiments are intended to illustrate the invention only and should not be taken as limiting the scope of the invention. If no specific conditions are specified in the examples, the conventional conditions or the conditions recommended by the manufacturer shall be followed. If the reagent or instrument used does not indicate the manufacturer, it is a conventional product that can be purchased commercially.

[0031] EXAMPLE 1

[0032] The liquid fermentation method of Cordyceps militaris strain is as follows:

[0033] 1) In the first half of September each year, collect wild Cordyceps militaris fruiting bodies in Zuojiashan District of Jilin City, and select robust fruiting bodies for separation and purification. The medium is PDA medium, and liquid fermentation is carried out after successful separation and purification;

[0034] Preparing a liquid fermentation medium: squeezing freshly picked mature ginseng fruits through a juicer, coarsely filtering to remove ginseng seeds and pericarp, homogenizing the filtrate to obtain ginseng fruit juice, putting 1OOmL ginseng fruit juice into a 250mL triangular bottle, sterilizing at 120 °C for 20min, and obtaining a ginseng fruit juice fermentation matrix;

[0035] 3) Inoculating the bacteria obtained in the step 1) into the ginseng fruit juice fermentation matrix prepared in the step 2), and culturing in the table concentretor, controlling the temperature at 19°C and the rotating speed of the table cincentrator at 200rad/min, and determining the content of cordycepin and saponin in the fermentation product after dark culture for 8 days.

[0036] Specific determination method of cordycepin: the ratio of fermentation product to water is 1:15, water is added into the fermentation product, cells are crushed for 10min at 100OOr/min, centrifuged for 10min, taking and filtering the supernatant with aseptic filter membrane to detect cordycepin. The chromatographic conditions are as follows: chromatographic column: ACQUITY UPLC HSS T3 (2.1 mm x 50 mm, 1.8 m); Mobile phase: methanol-water (15: 85, v/v); Flow rate: 0.3 mL/min; Column temperature: 35 °C; Detection wavelength: 260nm; Injection volume: 2L. The content of cordycepin was 2.8 g/L.

[0037] Specific determination method of saponin content: The content of monomer saponins in the fermentation product was determined by high performance liquid chromatography, The specific method is as follows: the ratio of fermentation product to methanol is 1: 5, adding methanol into the fermentation product, crushing cells for 10min, carrying out ultrasonic wave for 30mmin, then 1OOr/min, centrifugation is carried out for 10min, supernatant is filtered by aseptic filter membrane, monomer saponins are detected, chromatographic conditions are: Acquity UPLC BEHC18 chromatographic column (2.1 mm x 50 mm, 1.7 m), mobile phase acetonitrile-water, gradient elution: 0-5min, 17%-19% acetonitrile; 5-7min, 19-21% of acetonitrile; 7-11min, 21-26% acetonitrile; 11-13min, 26-27% acetonitrile, 13-15min, 27-32% acetonitrile, 15-17min, 32-43% acetonitrile, 17-19min, 43-60% acetonitrile, flow rate 0.5 mL/min, detection wavelength 203nm, column temperature 35 °C, injection volume 2L. The contents of Rb1, Rb2, Rb3, Rc, Rd, F2, Rg3 were 0.13 g/L, 0.23 g/L, 1.56 g/L, 0.22 g/L, 0.67 g/L, 0.02 g/L, 0.14 g/L respectively.

[0038] EXAMPLE 2

[0039] The liquid fermentation method of Cordyceps militaris strain is as follows:

[0040] 1) In the first half of September each year, collect wild Cordyceps militaris fruiting bodies in Zuojiashan District of Jilin City, and select robust fruiting bodies for separation and purification. The medium is PDA medium, and liquid fermentation is carried out after accomplishing separation and purification;

[0041] 2) Preparing liquid fermentation medium: squeezing freshly picked mature American ginseng fruits through a juicer, coarsely filtering to remove ginseng seeds and pericarp, homogenizing the filtrate to obtain ginseng fruit juice, putting 100mL of ginseng fruit juice into a 250mL triangular bottle, sterilizing at 125 °C for 10mmin, and obtaining American ginseng fruit juice fermentation substrate;

[0042] 3) Inoculating the bacteria obtained in the step 1) into the ginseng fruit juice fermentation matrix prepared in the step 2), and culturing in the table concentrator, controlling the temperature at 21 °C and the rotating speed of the concentrator at 220 rad/min, and determining the content of cordycepin and saponin in the fermentation product after dark culture for 10 days.

[0043] The content of cordycepin was 2.6 g/L, and the content of monomer saponins Rbl, Rb2, Rb3, Rc, Rd, F2, Rg3 were 0.23 g/L, 0.31 g/L, 1.16 g/L, 0.32 g/L, 0.77 g/L, 0.03 g/L, 0.24 g/L respectively.

[0044] EXAMPLE 3

[0045] The liquid fermentation method of Cordyceps militaris strain is as follows:

[0046] 1) In the first half of September each year, collect wild Cordyceps militaris fruiting bodies in Zuojiashan District of Jilin City, and select robust fruiting bodies for separation and purification. The medium is PDA medium, and liquid fermentation is carried out after accomplishing separation and purification;

[0047] 2) Preparation of liquid fermentation medium: processing ginseng straight whisker into small segment about 2cm, then pulverizing with a traditional Chinese medicine pulverizer, sieve the powder with 80 mesh, adding 3OmL of water to Ig of ginseng powder, refluxing and extracting for 3h, centrifuging at 8000rad/min for 15min, taking supernatant, adding 8g of glucose to 1L of water extract, putting1OOmL of water extract into 250mL triangular bottle, sterilizing at 120 °C for min to obtain fermentation substrate of ginseng straight whisker powder;

The specific determination method was the same as that of Example 1. After detection, the content of cordycepin was 3.5 g/L, and the contents of monomer saponins Rbl, Rb2, Rb3, Rc, Rd, F2, Rg3 were 0.36 g/L, 1.56 g/L, 0.67 g/L, 0.68 g/L, 3.87 g/LO.05 g/L, 0.86 g/L. respectively.

[0048] EXAMPLE 4

[0049] A method for liquid fermentation of Cordyceps militaris strain is as follows:

[0050] 1) In the first half of September each year, collect wild Cordyceps militaris fruiting bodies in Zuojiashan District of Jilin City, and select robust fruiting bodies for separation and purification. The medium is PDA medium, and liquid fermentation is carried out after accomplishing separation and purification;

[0051] 2) Prepartation of liquid fermentation medium: the straight whisker of American ginseng is treated into 3cm small segments, then pulverized with a Chinese medicine pulverizer, the powder is sieved through a 100-mesh sieve, adding lg of American ginseng powder with mL of water, refluxed and extracted for 4h, then centrifuged at

10000rad/min for 20min, taking supernatant, adding IL of water extract with 1Og of glucose, 250mL of water extract is put into a triangular bottle for 100mL of water extract, sterilizing at 125 °C for 10min, to obtain the fermentation substrate of the water extract of American ginseng straight whisker.

[0052] 3) Inoculating the bacteria obtained in the step 1) into the fermentation matrix of the water extract of American ginseng root powder prepared in the step 2), and culturing in a table concentrator, controlling the temperature at 20 °C and the rotating speed of the shaking table at 21Orad/min, and determining the contents of cordycepin and saponin in the fermentation product after 14 days of dark culture.

[0053] The content of cordycepin was 3.3 g/L, and the content of monomer saponins Rbl, Rb2, Rb3, Rc, Rd, F2, Rg3 were 0.76 g/L, 1.26 g/L, 0.97 g/L, 0.78 g/L, 4.87 g/L, 0.08 g/L, 1.36 g/L respectively.

[0054] EXAMPLE 5

[0055] The liquid fermentation method of Cordyceps militaris strain is as follows:

[0056] 1) In the first half of September each year,collect wild Cordyceps militaris fruiting bodies in Zuojiashan District of Jilin City, and select robust fruiting bodies for separation and purification. The medium is PDA medium, and liquid fermentation is carried out after accomplishing separation and purification;

[0057] Preparing liquid fermentation medium: treating Panax notoginseng into small segments about 2cm, then pulverizing with a traditional Chinese medicine pulverizer, sieving the powder with 110 mesh, adding 35mL of water to lg of Panax notoginseng powder, refluxing and extracting for 4h, centrifuging at 9000rad/min for 20min, taking supernatant, adding 7g of glucose to IL of water extract, putting 100mL of water extract into 250mL triangular bottle, sterilizing at 120 °C for 20min to obtain fermentation substrate of Panax notoginseng powder water extract;

[0058] 3) Inoculating the bacteria obtained in the step 1) into the fermentation matrix of the water extract of Panax notoginseng powder prepared in the step 2), culture in the table concentrator, control the temperature at 20 °C, control the rotating speed of the table concentrator at 205rad/min, and determine the content of cordycepin and saponin in the fermentation product after dark culture for 12 days.

[0059] The content of cordycepin was 2.6 g/L, and the content of monomer saponins Rbl, Rb2, Rb3, Rc, Rd, F2, Rg3 were 0.96 g/L, 1.43 g/L, 0.67 g/L, 0.98 g/L, 4.57 g/L, 0.12 g/L, 1.56 g/L respectively.

[0060] EXAMPLE 6

[0061] The liquid fermentation method of Cordyceps militaris strain is as follows:

[0062] 1) In the first half of September each year, collect wild Cordyceps militaris fruiting bodies in Zuojiashan District of Jilin City, and select robust fruiting bodies for separation and purification. The medium is PDA medium, and liquid fermentation is carried out after accomplishing separation and purification.

[0063] Preparing liquid fermentation medium: treating Gynostemma pentaphyllum into small segments between 2 and 3cm, then pulverizing with a traditional Chinese medicine pulverizer, sieving the powder through a 100-mesh sieve, adding 40mL of water to lg of Gynostemma pentaphyllum powder, refluxing and extracting for 3h, centrifuging at 9000rad/min for 20min, taking supernatant, adding 9g of glucose to IL of water extract, putting 100mL of water extract into 250mL triangular bottle, sterilizing at 125 °C for 10min, and obtaining fermentation substrate of Gynostemma pentaphyllum powder water extract;

[0064] 3) Inoculating the bacteria obtained in the step 1) into the fermentation matrix of the water extract of Gynostemma pentaphyllum powder prepared in the step 2), culturing in a table concentrator, controlling the temperature at 21 °C, controlling the rotating speed of the table concentrator at 215rad/min, dark culturing for 13 days, and feeding the fermentation product into the fermentation product.

[0065] The content of cordycepin was 2.7 g/L, and the content of monomer saponins Rbl, Rb2, Rb3, Rc, Rd, F2, Rg3 were 0.76 g/L, 0.46 g/L, 0.77 g/L, 0.68 g/L, 3.57 g/L, 0.05 g/L, 0.96 g/L respectively.

[0066] COMPARATIVE EXAMPLE 1

[0067] The liquid fermentation method of Cordyceps militaris strain is as follows:

[0068] 1) In the first half of September each year, collect wild Cordyceps militaris fruiting bodies in Zuojiashan District of Jilin City, and select robust fruiting bodies for separation and purification. The medium is PDA medium, and liquid fermentation is carried out after accomplishing separation and purification;

[0069] Preparation of liquid fermentation medium: glucose 20g/L, yeast extract 5g/L, peptone 8g/L, potassium dihydrogen phosphate 0.5 g/L, potassium dihydrogen phosphate 0.5 g/L, solvent is water, taking 250mL triangular bottle into 100mL of the fermentation medium, 121 °C, and carrying out sterilization for 20min to obtain liquid fermentation medium;

[0070] 3) Inoculating the bacteria obtained in the step 1) into the liquid fermentation culture substrate prepared in the step 2), culturing in a table concentrator, controlling the temperature at 22 °C and the rotating speed of the table concentrator at 180rad/min, and determining the content of cordycepin and saponin in the fermentation product after dark culture for 20 days.

[0071] The specific determination method is the same as that of Example 1. After detection, the cordycepin content is 1.3 g/L and there is no saponin.

[0072] As can be seen from the above examples and comparative examples, the liquid fermentation medium of the embodiment of the present invention not only has a wide source of raw materials and a simple and easy preparation method, and also has a high cordycepin content in the product obtained after culture and fermentation by using the medium, which also has rare saponins by-product, thus having great subsequent development value.

[0073] Although the present invention has been illustrated and described with specific embodiments, it should be appreciated that many other changes and modifications may be made without departing from the spirit and scope of the invention. Therefore, this means that all such changes and modifications that falling within the scope of the present invention are included in the appended claims.

[0074] Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms, in keeping with the broad principles and the spirit of the invention described herein.

[0075] The present invention and the described preferred embodiments specifically include at least one feature that is industrial applicable.

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. A method for liquid fermentation of Cordyceps militaris strain, comprising the following steps: inoculating Cordyceps militaris strain in a liquid fermentation medium, cultivating in the table concentrator, controlling the temperature between 19 and 21°C; the rotation speed of the shaking table is controlled at 200-220 rad / min, and the dark culture is 8-14 days; the liquid fermentation medium is prepared from the fruits or roots of Acanthopanax plants.

2. The method for liquid fermentation of Cordyceps militaris strain according to claim 1, wherein the liquid fermentation culture medium is prepared from one of ginseng fruit, ginseng root, American ginseng fruit, American ginseng root, notoginseng and gynostemma pentaphyllum as raw materials; preferably, the liquid fermentation medium is made of one of ginseng fruit, ginseng root, American ginseng fruit and American ginseng root as the original material.

3. The method for liquid fermentation of Cordyceps militaris strain according to claim 2, wherein the preparation method of the liquid fermentation medium for ginseng fruit and American ginseng fruit comprises the following steps: picking fresh ginseng fruit or American ginseng fruit, squeezing and filtering the fruit to obtain fruit juice, and sterilizing at 120-125°C for 10-20min to obtain the product.

4. The method for liquid fermentation of Cordyceps militaris strain according to claim 3, wherein the sterilization temperature is controlled at 121-124 °C for 15-18min.

5. The method for liquid fermentation of Cordyceps militaris strain according to claim 2, wherein the method for preparing the liquid fermentation medium of ginseng root and American ginseng root comprises the following steps; cutting, crushing and sieving the ginseng root or American ginseng root, and add water to obtain the water extract, and then sterilizing after adding glucose.

6. The method for liquid fermentation of Cordyceps militaris strain according to claim 5, comprising cutting into blocks with a particle size of 1-2cm; preferably, the mesh size of the crushing and sieving is controlled to be 80 mesh or more, preferably 100 mesh or more.

7. The method for liquid fermentation of Cordyceps militaris strain according to claim 5, comprising the process of water addition extraction, the added water amount is 30-40ml of water per gram of American ginseng root or ginseng root; preferably, the extraction time is controlled at 3-4h; preferably, the extraction is followed by centrifugation for 15 min for purification, and the rate of centrifugation is controlled at 8000-10000rad/min; preferably, carry out the sterilization t for 10-20min between 120-125 °C.

8. The method for liquid fermentation of Cordyceps militaris strain according to claim 5, comprising 7-1Og of glucose, preferably 8-9g of glucose, are added to each litre of the aqueous extract.

9. The method for liquid fermentation of Cordyceps militaris strain according to any one of claims 2 to 8, wherein the Cordyceps militaris strain is inoculated in a liquid fermentation medium prepared from ginseng fruit and American ginseng fruit for 8 to 10 days; the Cordyceps militaris strain was inoculated into a liquid fermentation medium prepared by ginseng root and American ginseng root for 12-14 days.

10. The method for liquid fermentation of a Cordyceps militaris strain according to any one of claims 2 to 8, wherein the culture temperature is controlled between 20 and 21 °C, and the rotation speed of the table concentrator is controlled between 205 and 215 rad/min.