Fermentation culture medium for improving yield of astaxanthin produced by yarrowia lipolytica and method for producing astaxanthin at high yield by using fermentation culture medium

Abstract

The invention relates to the field of microbial fermentation, in particular to a fermentation medium for improving the yield of astaxanthin produced by yarrowia lipolytica and a method for producing astaxanthin at high yield by using the fermentation medium. The invention provides a fermentation culture medium for improving the yield of astaxanthin produced by yarrowia lipolytica, and when the fermentation culture medium provided by the invention is used for producing astaxanthin, a large amount of high-activity astaxanthin can be obtained. The invention also provides a method for increasing the yield of astaxanthin produced by yarrowia lipolytica based on the fermentation medium provided by the invention, in the method, the astaxanthin is produced by fermenting the yarrowia lipolytica, citric acid is added in different stages of thallus growth, so that more precursor acetyl coenzyme A flows to an astaxanthin synthesis route, and the yield of the astaxanthin is increased. By adopting the method, the yield of the astaxanthin is greatly improved, the fermentation cost is reduced, the fermentation period is shortened, the generated astaxanthin has a 100% levorotatory configuration, the biological activity is high, and the method has a wide application prospect in the field of feeds.

Description

Technical Field

[0001] The invention relates to the field of microbial fermentation, in particular to a fermentation medium for improving the astaxanthin production of Yarrowia lipolytica and a method for high-yield astaxanthin production. Background Art

[0002] Astaxanthin is a type of deep red keto-carotenoid with a purple-red appearance. It is fat-soluble and insoluble in water. Astaxanthin has three optical isomers: 3S, 3S' (levorotatory), 3R, 3S' (mesorotatory) and 3R, 3R' (dextrorotatory), of which 3S, 3S' has the strongest antioxidant capacity. Astaxanthin is the strongest antioxidant found in nature. Its antioxidant capacity is 6000 times that of vitamin C, 800 times that of lycopene, and 700 times that of anthocyanins. Astaxanthin has physiological effects such as delaying aging, inhibiting tumor occurrence, enhancing the body's immunity, preventing cardiovascular diseases, and removing free radicals in the body. Astaxanthin is widely used in health products, high-end cosmetics, medicine, aquaculture and other fields. Among them, feed is the most widely used field of astaxanthin. As a feed, it has the effects of coloring, anti-oxidation, improving survival rate, and promoting growth and reproduction.

[0003] The existing astaxanthin production methods mainly include natural extraction, chemical synthesis and microbial fermentation. The natural extraction method mainly uses the steps of crushing, wall breaking, hydrolysis and extraction to extract astaxanthin from aquatic product processing waste. It has the disadvantages of extremely low yield, complex process, high cost, and the extraction process is susceptible to pollution, which is not suitable for large-scale production. The chemical synthesis method mainly uses chemical raw materials to synthesize astaxanthin through multi-step reactions. The process is complicated. The synthesized product is astaxanthin with a mixed configuration (25% left-handed, 50% meso, 25% right-handed), and it also accumulates a variety of by-products. The absorption and utilization rate in the organism is much lower than that of naturally extracted astaxanthin, and it can only play a coloring role. The astaxanthin synthesized by microbial fermentation has the characteristics of clear configuration, environmental friendliness and few by-products. Therefore, the microbial fermentation method is a very promising astaxanthin production method. The most widely studied at present is the fermentation method of Haematococcus pluvialis and Phaffia rhodozyma. The astaxanthin produced by the fermentation of Haematococcus pluvialis is 100% left-handed, with high biological activity, and the proportion of astaxanthin in the dry weight of the bacteria can reach 3%. However, the production of astaxanthin by fermentation of Haematococcus pluvialis has the disadvantages of long growth cycle, low light energy utilization, large environmental pollution and difficult extraction, so the production cost is relatively high. The production process of Phaffia rhodozyma is easy to control and the fermentation cycle is short, but the astaxanthin produced is 100% right-handed, with only partial biological activity and low dry weight content.

[0004] Based on the problems encountered in the industrial application of astaxanthin production by bio-fermentation, such as high cost, long cycle and low biological activity of the right-handed configuration, it is very necessary to find a method with low cost, short cycle and high biological activity to obtain astaxanthin. Summary of the invention

[0005] The purpose of the present invention is to provide a fermentation medium for increasing the astaxanthin production of Yarrowia lipolytica and a method for high astaxanthin production, so as to solve the problems existing in the above-mentioned prior art. By using the fermentation medium provided by the present invention to produce astaxanthin, a large amount of highly active astaxanthin can be obtained; at the same time, the fermentation process has the advantages of low cost and short cycle.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] The present invention provides a fermentation medium for improving the astaxanthin production of Yarrowia lipolytica, wherein the fermentation medium comprises fermentation medium I or fermentation medium II;

[0008] The fermentation medium I includes the following components in concentrations: 20-50 g / L corn steep liquor, 20-50 g / L soybean meal powder, 20 g / L glucose, 2 mL / L trace elements, 1 mL / L vitamins, and 1 g / L polyether defoamer;

[0009] The fermentation medium II includes the following components in concentrations: 20-50 g / L corn steep liquor, 20-50 g / L soybean meal powder, 10-40 g / L citric acid, 20 g / L glucose, 2 mL / L trace elements, 1 mL / L vitamins, and 1 g / L polyether defoamer;

[0010] The trace elements include the following components at the following concentrations: CoCl 2 ·2H 2 O 4g / L, ZnSO 4 7H 2 O 5.5g / L, FeSO 4 7H 2 O3.6g / L, H 3 BO 3 1.1g / L, MnCl 2 ·4H 2 O 1.2g / L, Na 2 Mo 4 ·2H 2 O 0.6g / L, CoCl 2 6H 2 O0.4g / L, CuSO 4 ·5H 2 O 0.16 g / L, KI 0.16 g / L and EDTA 12 g / L;

[0011] The vitamins include components with the following concentrations: biotin 45 mg / L, p-aminobenzoic acid 185 mg / L, niacin 1.2 g / L, calcium pantothenate 0.8 g / L, pyridoxine hydrochloride 0.9 g / L, thiamine hydrochloride 0.8 g / L and inositol 22 g / L.

[0012] Further preferably, the fermentation medium I comprises the following components in concentrations: 50 g / L corn steep liquor, 50 g / L soybean meal powder, 20 g / L glucose, 2 mL / L trace elements, 1 mL / L vitamins and 1 g / L polyether defoamer;

[0013] The fermentation medium II includes the following components: 50 g / L corn steep liquor, 50 g / L soybean meal powder, 20 g / L citric acid, 20 g / L glucose, 2 mL / L trace elements, 1 mL / L vitamins, and 1 g / L polyether defoamer;

[0014] The trace elements include the following components at the following concentrations: CoCl 2 ·2H 2 O 4g / L, ZnSO 4 7H 2 O 5.5g / L, FeSO 4 7H 2 O3.6g / L, H 3 BO 3 1.1g / L, MnCl 2 ·4H 2 O 1.2g / L, Na 2 Mo 4 ·2H 2 O 0.6g / L, CoCl 2 6H 2 O0.4g / L, CuSO 4 ·5H 2 O 0.16 g / L, KI 0.16 g / L and EDTA 12 g / L;

[0015] The vitamins include components with the following concentrations: biotin 45 mg / L, p-aminobenzoic acid 185 mg / L, niacin 1.2 g / L, calcium pantothenate 0.8 g / L, pyridoxine hydrochloride 0.9 g / L, thiamine hydrochloride 0.8 g / L and inositol 22 g / L.

[0016] The present invention provides application of the fermentation medium in improving the astaxanthin production of Yarrowia lipolytica.

[0017] The present invention provides a method for improving the astaxanthin production of Yarrowia lipolytica, comprising the following steps:

[0018] inoculating the activated Yarrowia lipolytica into a seed culture medium for culturing to obtain a seed solution of the Yarrowia lipolytica;

[0019] The seed liquid is inoculated into the above-mentioned fermentation medium for fermentation culture to obtain a fermentation liquid containing the astaxanthin.

[0020] Preferably, when the fermentation medium is fermentation medium I, the fermentation culture process further includes a step of adding citric acid.

[0021] Preferably, the added amount of citric acid is 10-40 g / L.

[0022] Further preferably, the added amount of citric acid is 20 g / L.

[0023] Preferably, when the OD of the fermentation broth obtained by the fermentation culture is 600 When the value reaches 50-200, the citric acid is added.

[0024] Preferably, the fermentation culture process further includes the steps of supplementing carbon source and adjusting pH.

[0025] Preferably, the carbon source is 60 wt.% glucose; the agent used to adjust the pH is ammonia water, and the pH is adjusted to 5.5.

[0026] Preferably, the inoculation amount of the seed liquid is 2%-10%; the fermentation culture conditions include a temperature of 33°C, a time of 36h-72h, an initial stirring speed of 400rpm, the dissolved oxygen is controlled between 20-30% by increasing the stirring, the maximum stirring speed is 800rpm, the ventilation volume is 1vvm, and the tank pressure is 0.04MPa.

[0027] Preferably, the seed culture medium comprises components in the following concentrations: 10 g / L yeast extract, 20 g / L peptone and 20 g / L glucose.

[0028] The present invention discloses the following technical effects:

[0029] The present invention provides a fermentation medium for increasing the astaxanthin production of Yarrowia lipolytica. By using the fermentation medium provided by the present invention to produce astaxanthin, a large amount of highly active astaxanthin can be obtained. The results of the specific embodiments of the present invention show that after culturing Yarrowia lipolytica with the medium, the content of astaxanthin in the obtained fermentation broth is between 1567mg / L and 2350mg / L, and the generated astaxanthin has a 100% left-handed configuration and high biological activity. It can be seen that the fermentation medium can significantly increase the yield of highly active astaxanthin in the fermentation broth of Yarrowia lipolytica.

[0030] The present invention also provides a method for increasing the astaxanthin production of Yarrowia lipolytica based on the fermentation medium provided by the present invention. In the method, the present invention utilizes Yarrowia lipolytica to ferment and produce astaxanthin, and adds citric acid at different stages of bacterial growth to allow the precursor acetyl-CoA to flow more to the astaxanthin synthesis pathway, thereby greatly increasing the astaxanthin production, reducing the fermentation cost and fermentation cycle, and the generated astaxanthin has a 100% left-handed configuration and high biological activity, and has broad application prospects in the feed field. DETAILED DESCRIPTION

[0031] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0032] It should be understood that the terms described in the present invention are only for describing a particular embodiment and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. The intermediate value in any stated value or stated range, and each smaller range between any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0033] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0034] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present invention description and examples are exemplary only.

[0035] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0036] The Yarrowia lipolytica used in the present invention is Yarrowia lipolytica XS-8, which was deposited in the General Microbiology Center (CGMCC) of the China Microbiological Collection Administration on September 2, 2024, and the deposit address is the Institute of Microbiology, Chinese Academy of Sciences, No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, and the deposit number is CGMCC No. 31853;

[0037] The polyether defoamer was purchased from Jiangsu Jinhu County Geleite Silicone Products Factory, model GLT-690.

[0038] Example 1

[0039] The steps of this embodiment are as follows:

[0040] 1) Seed solution preparation: Take a glycerol tube of Yarrowia lipolytica from a -80°C refrigerator, take 800 μL from the glycerol tube and inoculate it into 250 mL of seed culture medium, and culture at 30°C and 220 rpm for 24 h until the OD 600 The value is 15 to obtain the seed solution. The seed culture medium formula is: yeast extract 10g / L, peptone 20g / L, glucose 20g / L.

[0041] 2) Preparation and sterilization of fermentation medium: The fermentation medium formula is corn syrup 50g / L, soybean meal powder 50g / L, glucose 20g / L, trace elements 2mL / L, vitamins 1mL / L, polyether defoamer 1g / L; the trace element mother solution formula is CoCl 2 ·2H 2 O4g / L, ZnSO 4 7H 2 O 5.5g / L, FeSO 4 7H 2 O 3.6g / L, H 3 BO 3 1.1g / L, MnCl 2 ·4H 2 O 1.2g / L, Na 2 Mo 4 ·2H 2 O 0.6g / L, CoCl 2 6H 2 O 0.4g / L, CuSO 4 ·5H 2O 0.16g / L, KI 0.16g / L, EDTA 12g / L; the vitamin mother solution formula is biotin 45mg / L, p-aminobenzoic acid 185mg / L, niacin 1.2g / L, calcium pantothenate 0.8g / L, pyridoxine hydrochloride 0.9g / L, thiamine hydrochloride 0.8g / L, inositol 22g / L; the sterilization temperature is 121℃, 30min.

[0042] 3) Fermentation and production of astaxanthin: The seed liquid is inoculated with 10% of the inoculation amount in a fermentation tank, and the culture temperature is 33°C and the pH is 5.5. The initial stirring speed is 400rpm, and the dissolved oxygen is controlled between 20-30% by increasing the stirring. The maximum stirring speed is 800rpm, the ventilation volume is 1vvm, and the tank pressure is 0.04MPa. A 60wt.% glucose solution is added to supplement the carbon source. By measuring the glucose content in the fermentation liquid, the sugar supplement rate is adjusted to control the glucose concentration at 5-10g / L. The present invention controls the glucose concentration in the fermentation liquid to be about 5g / L, and automatically adds ammonia water to adjust the pH to 5.5 (ammonia water addition is based on the pH of the fermentation liquid measured by the pH electrode, and the fermentation tank automatically adds ammonia water to control the set pH value to 5.5). After 72h of fermentation, the astaxanthin content, dry weight of the bacteria and dry weight of astaxanthin in the fermentation liquid were investigated. The results showed that after 72 hours of fermentation, the astaxanthin content in the fermentation liquid was 1567 mg / L, the dry weight of the bacteria was 83 g / L, and the dry weight content of astaxanthin was 1.888%.

[0043] Example 2

[0044] The steps of this embodiment are as follows:

[0045] 1) Seed solution preparation: Take a glycerol tube of Yarrowia lipolytica from a -80°C refrigerator, take 800 μL from the glycerol tube and inoculate it into 250 mL of seed culture medium, and culture at 30°C and 220 rpm for 24 h until the OD 600 The value is 15, and the seed solution is obtained. The seed culture medium formula is the same as that in Example 1;

[0046] 2) Preparation and sterilization of fermentation medium: The fermentation medium formula is 50 g / L corn syrup, 50 g / L soybean meal, 20 g / L citric acid, 20 g / L glucose, 2 mL / L trace elements, 1 mL / L vitamins, and 1 g / L polyether defoaming agent; the formula of the trace element mother solution is the same as that of Example 1; the formula of the vitamin mother solution is the same as that of Example 1; the sterilization temperature is 121° C., 30 min.

[0047] 3) Fermentation and production of astaxanthin: The seed liquid was inoculated with 10% of the inoculation amount into the fermentation tank, the culture temperature was 33°C, and the pH was 5.5. The initial stirring speed was 400rpm, and the dissolved oxygen was controlled between 20-30% by increasing the stirring. The maximum stirring speed was 800rpm, the ventilation volume was 1vvm, and the tank pressure was 0.04MPa. A 60wt.% glucose solution was added to supplement the carbon source, the glucose concentration in the fermentation liquid was controlled to be about 5g / L, and ammonia water was automatically added to adjust the pH to 5.5. After 72h of fermentation, the astaxanthin content, the dry weight of the bacteria, and the dry weight of astaxanthin in the fermentation liquid were investigated. The results showed that the astaxanthin content in the fermentation liquid obtained after 72h of fermentation was 2020mg / L, the dry weight of the bacteria was 85g / L, and the dry weight of astaxanthin was 2.376%.

[0048] Example 3

[0049] The steps of this embodiment are as follows:

[0050] 1) Seed solution preparation: Take a glycerol tube of Yarrowia lipolytica from a -80°C refrigerator, take 800 μL from the glycerol tube and inoculate it into 250 mL of seed culture medium, and culture at 30°C and 220 rpm for 24 h until the OD 600 The seed culture medium formula is the same as that in Example 1.

[0051] 2) Preparation and sterilization of fermentation medium: The fermentation medium formula is 50 g / L corn syrup, 50 g / L soybean meal powder, 20 g / L glucose, 2 mL / L trace elements, 1 mL / L vitamins, and 1 g / L polyether defoaming agent; the formula of the trace element mother solution is the same as that of Example 1; the formula of the vitamin mother solution is the same as that of Example 1; the sterilization temperature is 121° C., 30 min.

[0052] 3) Fermentation and production of astaxanthin: The seed liquid was inoculated with 10% of the inoculation amount into the fermentation tank, the culture temperature was 33°C, and the pH was 5.5. The initial stirring speed was 400rpm, and the dissolved oxygen was controlled between 20-30% by increasing the stirring. The maximum stirring speed was 800rpm, the ventilation volume was 1vvm, and the tank pressure was 0.04MPa. A 60wt.% glucose solution was added to supplement the carbon source, and the glucose concentration in the fermentation liquid was controlled to be about 5g / L. Ammonia water was automatically added to adjust the pH to 5.5. When the OD of the bacterial liquid reached 0.5, the pH value was 0.1. 600 When the value reaches 50 (the beginning of the logarithmic growth phase, about 10-12h), citric acid is added. The amount of citric acid added is 20g / L, calculated based on the volume of the initial fermentation liquid. After 72h of fermentation, the astaxanthin content, bacterial dry weight and astaxanthin dry weight in the fermentation liquid were investigated. The results showed that the astaxanthin content in the fermentation liquid obtained after 72h of fermentation was 1975mg / L, the bacterial dry weight was 84.3g / L, and the astaxanthin dry weight content was 2.343%.

[0053] Example 4

[0054] The steps of this embodiment are as follows:

[0055] 1) Seed solution preparation: Take a glycerol tube of Yarrowia lipolytica from a -80°C refrigerator, take 800 μL from the glycerol tube and inoculate it into 250 mL of seed culture medium, and culture at 30°C and 220 rpm for 24 h until the OD 600 The seed culture medium formula is the same as that in Example 1.

[0056] 2) Preparation and sterilization of fermentation medium: The fermentation medium formula is 50 g / L corn syrup, 50 g / L soybean meal powder, 20 g / L glucose, 2 mL / L trace elements, 1 mL / L vitamins, and 1 g / L polyether defoaming agent; the formula of the trace element mother solution is the same as that of Example 1; the formula of the vitamin mother solution is the same as that of Example 1; the sterilization temperature is 121° C., 30 min.

[0057] 3) Fermentation and production of astaxanthin: The seed liquid was inoculated with 10% of the inoculation amount into the fermentation tank, the culture temperature was 33°C, and the pH was 5.5. The initial stirring speed was 400rpm, and the dissolved oxygen was controlled between 20-30% by increasing the stirring. The maximum stirring speed was 800rpm, the ventilation volume was 1vvm, and the tank pressure was 0.04MPa. A 60wt.% glucose solution was added to supplement the carbon source, and the glucose concentration in the fermentation liquid was controlled to be about 5g / L. Ammonia water was automatically added to adjust the pH to 5.5. When the OD of the bacterial liquid reached 0.5, the pH value was 0.1. 600 When the value reaches 100 (mid-logarithmic growth phase, about 18-20h), citric acid is added. The amount of citric acid added is 20g / L, calculated based on the volume of the initial fermentation liquid. After 72h of fermentation, the astaxanthin content, bacterial dry weight and astaxanthin dry weight in the fermentation liquid were investigated. The results showed that the astaxanthin content in the fermentation liquid obtained after 72h of fermentation was 2350mg / L, the bacterial dry weight was 86.8g / L, and the astaxanthin dry weight content was 2.707%.

[0058] Example 5

[0059] The steps of this embodiment are as follows:

[0060] 1) Seed solution preparation: Take a glycerol tube of Yarrowia lipolytica from a -80°C refrigerator, take 800 μL from the glycerol tube and inoculate it into 250 mL of seed culture medium, and culture at 30°C and 220 rpm for 24 h until the OD 600 The seed culture medium formula is the same as that in Example 1.

[0061] 2) Preparation and sterilization of fermentation medium: The fermentation medium formula is 50 g / L corn syrup, 50 g / L soybean meal powder, 20 g / L glucose, 2 mL / L trace elements, 1 mL / L vitamins, and 1 g / L polyether defoaming agent; the formula of the trace element mother solution is the same as that of Example 1; the formula of the vitamin mother solution is the same as that of Example 1; the sterilization temperature is 121° C., 30 min.

[0062] 3) Fermentation and production of astaxanthin: The seed liquid was inoculated with 10% of the inoculation amount into the fermentation tank, the culture temperature was 33°C, and the pH was 5.5. The initial stirring speed was 400rpm, and the dissolved oxygen was controlled between 20-30% by increasing the stirring. The maximum stirring speed was 800rpm, the ventilation volume was 1vvm, and the tank pressure was 0.04MPa. A 60wt.% glucose solution was added to supplement the carbon source, and the glucose concentration in the fermentation liquid was controlled to be about 5g / L. Ammonia water was automatically added to adjust the pH to 5.5. When the OD of the bacterial liquid reached 0.5, the pH value was 0.1. 600 When the value reaches 200 (late logarithmic growth phase, about 24-28h), 20g / L citric acid is added. After 72h of fermentation, the astaxanthin content, bacterial dry weight and astaxanthin dry weight in the fermentation broth were investigated. The results showed that after 72h of fermentation, the astaxanthin content in the fermentation broth was 2178mg / L, the bacterial dry weight was 85.5g / L, and the astaxanthin dry weight content was 2.547%.

[0063] Moreover, the corn steep liquor and soybean meal powder used in the present invention are low-priced nitrogen source components compared to traditional peptones, yeast powder, etc., and are suitable for industrial production. At present, the fermentation time of astaxanthin is generally more than 120 hours, or even 240 hours. In comparison, the present invention significantly shortens the fermentation time and saves time cost. The astaxanthin configuration produced by Yarrowia lipolytica is 100% left-handed, which is confirmed by liquid chromatography and can be found in many documents. The astaxanthin fermented by red Phaffia yeast commonly found on the market is 100% right-handed, and the biological activity of left-handed astaxanthin is higher than that of right-handed astaxanthin. In summary, the culture medium and method provided by the present invention reduce the fermentation cost and fermentation cycle, and the generated astaxanthin configuration is 100% left-handed, which has high biological activity and has broad application prospects in the field of feed.

[0064] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A fermentation medium for improving the astaxanthin production of Yarrowia lipolytica, characterized in that: The fermentation medium includes fermentation medium I or fermentation medium II; The fermentation medium I includes the following components in concentrations: 20-50 g / L corn steep liquor, 20-50 g / L soybean meal powder, 20 g / L glucose, 2 mL / L trace elements, 1 mL / L vitamins, and 1 g / L polyether defoamer; The fermentation medium II includes the following components in concentrations: 20-50 g / L corn steep liquor, 20-50 g / L soybean meal powder, 10-40 g / L citric acid, 20 g / L glucose, 2 mL / L trace elements, 1 mL / L vitamins, and 1 g / L polyether defoamer; The trace elements include components with the following concentrations: CoCl2·2H2O 4g / L, ZnSO4·7H2O 5.5g / L, FeSO4·7H2O 3.6g / L, H3BO3 1.1g / L, MnCl2·4H2O 1.2g / L, Na2Mo4·2H2O 0.6g / L, CoCl2·6H2O 0.4g / L, CuSO4·5H2O 0.16g / L, KI 0.16g / L and EDTA 12g / L; The vitamins include components with the following concentrations: biotin 45 mg / L, p-aminobenzoic acid 185 mg / L, niacin 1.2 g / L, calcium pantothenate 0.8 g / L, pyridoxine hydrochloride 0.9 g / L, thiamine hydrochloride 0.8 g / L and inositol 22 g / L.

2. Use of the fermentation medium according to claim 1 in increasing the astaxanthin production of Yarrowia lipolytica.

3. A method for increasing the astaxanthin production of Yarrowia lipolytica, characterized in that: The following steps are involved: inoculating the activated Yarrowia lipolytica into a seed culture medium for culturing to obtain a seed solution of the Yarrowia lipolytica; The seed liquid is inoculated into the fermentation medium according to claim 1 for fermentation culture to obtain a fermentation liquid containing the astaxanthin.

4. The method according to claim 3, characterized in that When the fermentation medium is fermentation medium I, the fermentation culture process further includes the step of adding citric acid.

5. The method according to claim 4, characterized in that The added amount of the citric acid is 10-40 g / L.

6. The method according to claim 4, characterized in that When the OD of the fermentation broth obtained by the fermentation culture is 600 When the value reaches 50-200, the citric acid is added.

7. The method according to claim 3, characterized in that The fermentation culture process also includes the steps of supplementing carbon source and adjusting pH.

8. The method according to claim 7, characterized in that The carbon source is 60 wt.% glucose; the preparation used for adjusting the pH is ammonia water, and the pH is adjusted to 5.

5.

9. The method according to claim 3, characterized in that: The inoculation amount of the seed liquid is 2%-10%; the fermentation culture conditions include a temperature of 33°C, a time of 36h-72h, an initial stirring speed of 400rpm, the dissolved oxygen is controlled between 20-30% by increasing the stirring, the maximum stirring speed is 800rpm, the ventilation volume is 1vvm, and the tank pressure is 0.04MPa.

10. The method according to claim 3, characterized in that The seed culture medium includes components with the following concentrations: 10 g / L yeast extract, 20 g / L peptone, and 20 g / L glucose.