阅读说明：本技术 一种3-羟基丙酸的补料发酵生产方法 (Supplementary fermentation production method of 3-hydroxypropionic acid ) 是由 王陶 李文 杨英歌 董玉玮 张传丽 于 2021-10-11 设计创作，主要内容包括：本发明公开了一种3-羟基丙酸的补料发酵生产方法,属于微生物发酵技术领域；本发明所用菌株为汉逊德巴利酵母(Debaryomyceshansenii.)菌株IS451,保藏号为：CGMCC No.11893；发酵过程分为三个阶段：第一阶段为接种后48h内,第二阶段为接种后的第49-96h,第三阶段为接种后的第97-114h,所述第二阶段进行补料操作,补料成分为：葡萄糖、(NH-(4))-(2)SO-(4)、丙酸和甘油；所述第三阶段进行补料操作,补料成分为：葡萄糖、丙酸和植物油；利用本发明的生产方法,使得3-羟基丙酸的发酵产量提升至58.39g/L,发酵周期降低至114h。(The invention discloses a supplemented material fermentation production method of 3-hydroxypropionic acid, belonging to the technical field of microbial fermentation; the strain used by the invention IS Debaryomyces hansenii (Debaryomyces hansenii.) strain IS451 with the preservation number: CGMCC No. 11893; the fermentation process is divided into three stages: the first stage is within 48 hours after inoculation, the second stage is 49-96 hours after inoculation, the third stage is 97-114 hours after inoculation, the second stage is subjected to feeding operation, and the feeding components are as follows: glucose, (NH) 4 ) 2 SO 4 Propionic acid and glycerol; the third stage is used for feeding, and the feeding components are as follows: glucose, propionic acid and vegetable oils; by using the production method, the fermentation yield of the 3-hydroxypropionic acid is increased to 58.39g/L, and the fermentation period is reduced to 114 h.)

1. A fed-batch fermentation production method of 3-hydroxypropionic acid is characterized in that,

the strain used IS Debaryomyces hansenii (Debaryomyces hansenii) strain IS451 with the accession number: CGMCC No. 11893;

the fermentation process is divided into three stages: the first stage is within 48 hours after inoculation, the second stage is 49-96 hours after inoculation, and the third stage is 97-114 hours after inoculation;

the fermentation medium of the first stage of the fermentation process comprises: 20g/L of glucose, 10g/L of yeast extract, 5g/L of yeast powder and 3g/L, KH g of soybean meal₂PO₄ 5g/L、K₂HPO₄ 2g/L、(NH₄)₂SO₄ 10g/L、MgSO₄·7H₂O 1g/L、FeSO₄·7H₂0.03g/L of O, 10-15g/L of propionic acid and 5-10g/L of glycerol;

and the second stage carries out material supplementing operation, and the material supplementing components are as follows: glucose 8g/L, (NH)₄)₂SO₄5g/L, 5g/L propionic acid and 5g/L glycerol;

the third stage is used for feeding, and the feeding components are as follows: 5g/L of glucose, 5g/L of propionic acid and 15g/L of vegetable oil.

2. The production method according to claim 1, wherein the fermentation regulation comprises the steps of:

the pH value of the first stage is controlled to be 5.0-6.0, the temperature is 30 ℃, and the dissolved oxygen is controlled to be 35-40%;

the pH value of the second stage is controlled to be 5.5-6.0, the temperature is 30 ℃, and the dissolved oxygen is controlled to be 20-30%;

the pH value of the third stage is controlled to be 5.5-6.0, the temperature is 30 ℃, and the dissolved oxygen is controlled to be 5-10%.

3. The production method according to claim 1, wherein in the second stage of feeding operation, the glycerol is added at once at 49h after inoculation, and the glucose, (NH) is added₄)₂SO₄And propionic acid starts feeding at 49h after inoculation, and the feeding time is 1.5-2 h.

4. The production method according to claim 1, wherein in the feeding operation of the third stage, the vegetable oil is fed at once at 97h after the inoculation, and the feeding of the glucose and the propionic acid is started at 97h after the inoculation, and the feeding time is 1.5-2 h.

5. The method of claim 1, wherein the fed-batch fermentation process further comprises strain activation and seed culture operations.

6. The method for producing the strain of claim 5, wherein the slant culture medium for strain activation is: 20g/L of glucose, 10g/L of yeast extract, 20g/L of peptone and 20g/L of agar powder.

7. The production method according to claim 5, wherein the seed culture medium used for the seed culture is: 20g/L glucose, 10g/L yeast extract, (NH)₄)₂SO₄10g/L yeast powder 5g/L, KH₂PO₄ 5g/L、K₂HPO₄2g/L、MgSO₄·7H₂O 1g/L、FeSO₄·7H₂O 0.03g/L。

8. The method of claim 1, wherein the first stage fermentation medium is inoculated with a seed in an amount of 10-15% by volume of the fermentation medium.

9. The method of claim 1, wherein the vegetable oil comprises canola oil, peanut oil, soybean oil, or corn oil.

Technical Field

The invention relates to the technical field of microbial fermentation, in particular to a supplemented fermentation production method of 3-hydroxypropionic acid.

Background

3-Hydroxypropionic acid (3-Hydroxypropionic acid, also known as β -Hydroxypropionic acid, abbreviated as 3-HP) is a three-carbon, non-chiral organic acid, which is an isomer with lactic acid. The 3-hydroxypropionic acid has two functional groups of hydroxyl and carboxyl, is a precursor of a plurality of optically active substances, can generate acrylic acid by dehydration, generate malonic acid by oxidation, generate 1, 3-propanediol by reduction, and generate a high molecular material by polymerization, and is an important chemical platform product.

At present, many colleges and research institutions are dedicated to the development make internal disorder or usurp of the microbial synthesis of 3-HP, which relies mainly on known metabolic pathways in microorganisms. The patent CN105861341A successfully screens out a Debaryomyces hansenii (Debaryomyces hansenii.) strain IS451, the fermentation yield of 3-hydroxypropionic acid reaches 48.96g/L, the fermentation period IS 5 days, but the fermentation yield of the Debaryomyces hansenii IS still required to be further improved when the Debaryomyces hansenii IS applied to industrial production, and the fermentation period IS further shortened, so that the method has important practical significance for reducing the production product and improving the productivity of enterprises. Because different microorganisms have different metabolism and growth characteristics, it IS necessary to optimize the fermentation regulation of Debaryomyces hansenii (Debaryomyces hansenii) strain IS451 to improve the fermentation yield of 3-hydroxypropionic acid and reduce the fermentation period.

Disclosure of Invention

The invention aims to provide a feeding fermentation production method of 3-hydroxypropionic acid, which aims to solve the problems in the prior art, improve the fermentation yield of the 3-hydroxypropionic acid based on Debaryomyces hansenii strain IS451 and reduce the fermentation period of the 3-hydroxypropionic acid.

In order to achieve the purpose, the invention provides the following scheme:

the invention provides a feeding fermentation production method of 3-hydroxypropionic acid, the used strain IS Debaryomyces hansenii (Debaryomyces hansenii.) strain IS451 with the preservation number: CGMCC No. 11893;

the fermentation process is divided into three stages: the first stage is within 48 hours after inoculation, the second stage is 49-96 hours after inoculation, and the third stage is 97-114 hours after inoculation;

the fermentation medium of the first stage of the fermentation process comprises: 20g/L of glucose, 10g/L of yeast extract, 5g/L of yeast powder and 3g/L, KH g of soybean meal₂PO₄ 5g/L、K₂HPO₄ 2g/L、(NH₄)₂SO₄ 10g/L、MgSO₄·7H₂O 1g/L、FeSO₄·7H₂0.03g/L of O, 10-15g/L of propionic acid and 5-10g/L of glycerol;

and the second stage carries out material supplementing operation, and the material supplementing components are as follows: glucose 8g/L, (NH)₄)₂SO₄5g/L, 5g/L propionic acid and 5g/L glycerol;

the third stage is used for feeding, and the feeding components are as follows: 5g/L of glucose, 5g/L of propionic acid and 15g/L of vegetable oil.

Further, the fermentation regulation comprises the following steps:

the pH value of the first stage is controlled to be 5.0-6.0, the temperature is 30 ℃, and the dissolved oxygen is controlled to be 35-40%;

the pH value of the second stage is controlled to be 5.5-6.0, the temperature is 30 ℃, and the dissolved oxygen is controlled to be 20-30%;

the pH value of the third stage is controlled to be 5.5-6.0, the temperature is 30 ℃, and the dissolved oxygen is controlled to be 5-10%.

Further, in the second stage of feeding operation, the glycerol was added at once at 49h after inoculation, and the glucose, (NH)₄)₂SO₄And propionic acid starts feeding at 49h after inoculation, and the feeding time is 1.5-2 h.

Further, in the feeding operation of the third stage, the vegetable oil is added at once at 97h after inoculation, and the glucose and propionic acid are fed at 97h after inoculation, wherein the feeding time is 1.5-2 h.

Further, the fed-batch fermentation production method also comprises strain activation and seed culture operation.

Further, the slant culture medium for strain activation is as follows: 20g/L of glucose, 10g/L of yeast extract, 20g/L of peptone and 20g/L of agar powder.

Further, the seed cultureThe seed culture medium used was: 20g/L glucose, 10g/L yeast extract, (NH)₄)₂SO₄10g/L yeast powder 5g/L, KH₂PO₄ 5g/L、K₂HPO₄ 2g/L、MgSO₄·7H₂O 1g/L、FeSO₄·7H₂O 0.03g/L。

Further, the seed inoculation amount in the initial fermentation medium of the first stage is 10-15% of the volume of the initial fermentation medium.

Further, the vegetable oil comprises rapeseed oil, peanut oil, soybean oil or corn oil.

The invention discloses the following technical effects:

(1) the present invention uses a rapid nitrogen source ((NH)₄)₂SO₄) The formula of the fermentation medium matched with the slow-acting nitrogen source (yeast extract, yeast powder and soybean meal) can optimize the early-stage strain growth and the later-stage product accumulation of the Debaryomyces hansenii (Debaryomyces hansenii) strain IS 451;

(2) according to the invention, by means of feeding materials in stages, nutrient components in the culture medium are reasonably utilized, and the accumulation of products in the later stage of fermentation is improved;

(3) the invention controls the growth and reproduction speed of the strains in the early stage by regulating and controlling the pH value, the temperature and the dissolved oxygen in stages, and reasonably regulates and controls the stable accumulation of products in the middle and later stages of fermentation;

(4) in the later stage of fermentation, the fermentation liquor is too viscous, the rotating speed needs to be greatly increased to ensure that the dissolved oxygen is at a set level, but the extremely strong shearing force generated by the overlarge rotating speed has overlarge damage to microorganisms, and the normal accumulation of products is difficult to ensure, so the vegetable oil is added in the material supplementing process in the later stage, the increase of the dissolved oxygen in the fermentation liquor and the increase of the transmission rate of oxygen are facilitated, and in addition, the products can be dissolved in the fermentation liquor to play a role in removing product inhibition.

Detailed Description

Reference will now be made in detail to various exemplary embodiments of the invention, the detailed description should not be construed as limiting the invention but as a more detailed description of certain aspects, features and embodiments of the invention.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Further, for numerical ranges in this disclosure, it is understood that each intervening value, between the upper and lower limit of that range, is also specifically disclosed. Every smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in a stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference herein for the purpose of disclosing and describing the methods and/or materials associated with the documents. In case of conflict with any incorporated document, the present specification will control.

It will be apparent to those skilled in the art that various modifications and variations can be made in the specific embodiments of the present disclosure without departing from the scope or spirit of the disclosure. Other embodiments will be apparent to those skilled in the art from consideration of the specification. The description and examples are intended to be illustrative only.

As used herein, the terms "comprising," "including," "having," "containing," and the like are open-ended terms that mean including, but not limited to.

The strain used in the following examples IS Debaryomyces hansenii (Debaryomyces hansenii) strain IS451 with the accession number: CGMCC No. 11893.

Example 1

(1) Strain activation

Inoculating the debaryomyces hansenii strain IS451 in a slant culture medium for activation, and culturing at the constant temperature of 30 ℃ for 24 h; the subsequent 2 times of the above steps were repeated to complete the activation.

The slant culture medium used was: 20g/L of glucose, 10g/L of yeast extract, 20g/L of peptone and 20g/L of agar powder.

(2) Seed culture

Inoculating the activated strain into a seed liquid culture medium, and culturing at 30 ℃ for 48h in a constant temperature oscillator at the rotating speed of 180r/min to obtain IS451 strain seed liquid;

the seed culture medium used was: 20g/L glucose, 10g/L yeast extract, (NH)₄)₂SO₄10g/L yeast powder 5g/L, KH₂PO₄ 5g/L、K₂HPO₄ 2g/L、MgSO₄·7H₂O 1g/L、FeSO₄·7H₂O 0.03g/L。

(3) Fermentation culture

Inoculating the IS451 strain seed liquid into a fermentation culture medium according to the inoculation amount of 10% of the volume of the fermentation culture medium, wherein the fermentation culture medium comprises: 20g/L of glucose, 10g/L of yeast extract, 5g/L of yeast powder and 3g/L, KH g of soybean meal₂PO₄ 5g/L、K₂HPO₄ 2g/L、(NH₄)₂SO₄ 10g/L、MgSO₄·7H₂O 1g/L、FeSO₄·7H₂0.03g/L of O, 12g/L of propionic acid and 6g/L of glycerol.

Then, the fermentation process is divided into three stages for regulation and control: the first stage is within 48 hours after inoculation, the second stage is 49-96 hours after inoculation, and the third stage is 97-114 hours after inoculation;

the first stage is as follows: controlling the pH value to be 5.2, controlling the temperature to be 30 ℃, and controlling the dissolved oxygen to be 36%;

and a second stage: performing material supplement operation, wherein the material supplement components are as follows: glucose 8g/L, (NH)₄)₂SO₄5g/L, 5g/L propionic acid and 5g/L glycerin, wherein the glycerin is added once at 49h after inoculation, and glucose, (NH)₄)₂SO₄And propionic acid starts to feed the supplementary material at 49h after inoculation, and the feeding time is 2 h; the pH value of the stage is controlled to be 5.6, the temperature is 30 ℃, and the dissolved oxygen is controlled to be 25 percent;

and a third stage: performing material supplement operation, wherein the material supplement components are as follows: 5g/L of glucose, 5g/L of propionic acid and 15g/L of corn oil, wherein the vegetable oil is added once in 97h after inoculation, and the glucose and the propionic acid start to feed and supplement in 97h after inoculation, and the feeding time is 2 h; the pH value of the stage is controlled to be 5.8, the temperature is 30 ℃, and the dissolved oxygen is controlled to be 8%.

Fermenting for 114H, placing in a jar, sampling, and purifying with high performance liquid chromatography (chromatographic column: Ecosile C18 column (250mm × 4.6mm, 5 μm); mobile phase: 3% methanol, and H₃PO₄Adjusting the pH value to 2.0; detection conditions are as follows: an ultraviolet detector with the wavelength of 210nm, the column temperature of 35 ℃, the flow rate of 0.8mL/min and the sample injection amount of 20 mu L) detects the content of the 3-hydroxypropionic acid in the fermentation liquor, and the result is 58.39 g/L.

Example 2

(1) Strain activation

Inoculating the debaryomyces hansenii strain IS451 in a slant culture medium for activation, and culturing at the constant temperature of 30 ℃ for 24 h; the subsequent 2 times of the above steps were repeated to complete the activation.

The slant culture medium used was: 20g/L of glucose, 10g/L of yeast extract, 20g/L of peptone and 20g/L of agar powder.

(2) Seed culture

Inoculating the activated strain into a seed liquid culture medium, and culturing at 30 ℃ for 48h in a constant temperature oscillator at the rotating speed of 180r/min to obtain IS451 strain seed liquid;

the seed culture medium used was: 20g/L glucose, 10g/L yeast extract, (NH)₄)₂SO₄10g/L yeast powder 5g/L, KH₂PO₄ 5g/L、K₂HPO₄ 2g/L、MgSO₄·7H₂O 1g/L、FeSO₄·7H₂O 0.03g/L。

(3) Fermentation culture

Inoculating the IS451 strain seed liquid into a fermentation culture medium according to the inoculation amount of 15% of the volume of the fermentation culture medium, wherein the fermentation culture medium comprises: 20g/L of glucose, 10g/L of yeast extract, 5g/L of yeast powder and 3g/L, KH g of soybean meal₂PO₄ 5g/L、K₂HPO₄ 2g/L、(NH₄)₂SO₄ 10g/L、MgSO₄·7H₂O 1g/L、FeSO₄·7H₂0.03g/L of O, 10g/L of propionic acid and 5g/L of glycering/L。

Then, the fermentation process is divided into three stages for regulation and control: the first stage is within 48 hours after inoculation, the second stage is 49-96 hours after inoculation, and the third stage is 97-114 hours after inoculation;

the first stage is as follows: controlling the pH value to be 5.0, controlling the temperature to be 30 ℃, and controlling the dissolved oxygen to be 35%;

and a second stage: performing material supplement operation, wherein the material supplement components are as follows: glucose 8g/L, (NH)₄)₂SO₄5g/L, 5g/L propionic acid and 5g/L glycerin, wherein the glycerin is added once at 49h after inoculation, and glucose, (NH)₄)₂SO₄And propionic acid, starting feeding at 49h after inoculation, wherein the feeding time is 1.5 h; the pH value of the stage is controlled to be 5.5, the temperature is 30 ℃, and the dissolved oxygen is controlled to be 20 percent;

and a third stage: performing material supplement operation, wherein the material supplement components are as follows: 5g/L of glucose, 5g/L of propionic acid and 15g/L of corn oil, wherein the vegetable oil is added once in 97h after inoculation, and the glucose and the propionic acid start feeding and supplementing materials in 97h after inoculation, wherein the feeding time is 1.5 h; the pH value of the stage is controlled to be 5.5, the temperature is 30 ℃, and the dissolved oxygen is controlled to be 5%.

Fermenting for 114H, placing in a jar, sampling, and purifying with high performance liquid chromatography (chromatographic column: Ecosile C18 column (250mm × 4.6mm, 5 μm); mobile phase: 3% methanol, and H₃PO₄Adjusting the pH value to 2.0; detection conditions are as follows: an ultraviolet detector with the wavelength of 210nm, the column temperature of 35 ℃, the flow rate of 0.8mL/min and the sample injection amount of 20 mu L) detects the content of the 3-hydroxypropionic acid in the fermentation liquor, and the result is 56.70 g/L.

Example 3

(1) Strain activation

Inoculating the debaryomyces hansenii strain IS451 in a slant culture medium for activation, and culturing at the constant temperature of 30 ℃ for 24 h; the subsequent 2 times of the above steps were repeated to complete the activation.

The slant culture medium used was: 20g/L of glucose, 10g/L of yeast extract, 20g/L of peptone and 20g/L of agar powder.

(2) Seed culture

Inoculating the activated strain into a seed liquid culture medium, and culturing at 30 ℃ for 48h in a constant temperature oscillator at the rotating speed of 180r/min to obtain IS451 strain seed liquid;

the seed culture medium used was: 20g/L glucose, 10g/L yeast extract, (NH)₄)₂SO₄10g/L yeast powder 5g/L, KH₂PO₄ 5g/L、K₂HPO₄ 2g/L、MgSO₄·7H₂O 1g/L、FeSO₄·7H₂O 0.03g/L。

(3) Fermentation culture

Inoculating the IS451 strain seed liquid into a fermentation culture medium according to the inoculation amount of 15% of the volume of the fermentation culture medium, wherein the fermentation culture medium comprises: 20g/L of glucose, 10g/L of yeast extract, 5g/L of yeast powder and 3g/L, KH g of soybean meal₂PO₄ 5g/L、K₂HPO₄ 2g/L、(NH₄)₂SO₄ 10g/L、MgSO₄·7H₂O 1g/L、FeSO₄·7H₂0.03g/L of O, 15g/L of propionic acid and 10g/L of glycerol.

Then, the fermentation process is divided into three stages for regulation and control: the first stage is within 48 hours after inoculation, the second stage is 49-96 hours after inoculation, and the third stage is 97-114 hours after inoculation;

the first stage is as follows: controlling the pH value to be 5.5, controlling the temperature to be 30 ℃, and controlling the dissolved oxygen to be 40%;

and a second stage: performing material supplement operation, wherein the material supplement components are as follows: glucose 8g/L, (NH)₄)₂SO₄5g/L, 5g/L propionic acid and 5g/L glycerin, wherein the glycerin is added once at 49h after inoculation, and glucose, (NH)₄)₂SO₄And propionic acid, starting feeding at 49h after inoculation, wherein the feeding time is 1.5 h; the pH value of the stage is controlled to be 6.0, the temperature is 30 ℃, and the dissolved oxygen is controlled to be 30%;

and a third stage: performing material supplement operation, wherein the material supplement components are as follows: 5g/L of glucose, 5g/L of propionic acid and 15g/L of corn oil, wherein the vegetable oil is added once in 97h after inoculation, and the glucose and the propionic acid start feeding and supplementing materials in 97h after inoculation, wherein the feeding time is 1.5 h; the pH value of the stage is controlled to be 6.0, the temperature is 30 ℃, and the dissolved oxygen is controlled to be 10%.

After fermentation for 114h, the mixture was taken out of the tank, sampled and purified by high performance liquid chromatography (column: Ecosile C18 column (250 mm. times.4.6 mm, 5 μm);mobile phase: 3% methanol with H₃PO₄Adjusting the pH value to 2.0; detection conditions are as follows: an ultraviolet detector with the wavelength of 210nm, the column temperature of 35 ℃, the flow rate of 0.8mL/min and the sample injection amount of 20 mu L) detects the content of the 3-hydroxypropionic acid in the fermentation liquor, and the result is 57.91 g/L.

Experimental example 1

The corn oil of example 1 was replaced with rapeseed oil, peanut oil, soybean oil and castor oil, and the fermentation culture was performed in the same manner as in example 1, and the content of 3-hydroxypropionic acid in each fermentation broth was measured, and the results are shown in Table 1. As can be seen from Table 1, the addition of corn oil in the second stage can improve the fermentation effect well, probably because the chain length of fatty acid in the corn oil is suitable for being absorbed by the thallus, thereby facilitating the production of 3-hydroxypropionic acid; the addition of castor oil greatly reduces the content of 3-hydroxypropionic acid in the fermentation broth, which may be related to the inhibition of the growth of bacteria in the fermentation broth by the antibacterial substances in the castor oil.

TABLE 1

Vegetable oil	The content of 3-hydroxypropionic acid in the fermentation liquor is g/L
		Corn oil	58.39
Rapeseed oil	55.85
		Peanut oil	56.41
Soybean oil	55.00
		Castor oil	50.02

Comparative example 1

The only difference from example 1 is that the fermentation medium is not fed with a feed, and all the fermentation medium components are added at once, i.e. the fermentation medium is: 33g/L of glucose, 10g/L of yeast extract, 5g/L of yeast powder and 3g/L, KH g of soybean meal₂PO₄ 5g/L、K₂HPO₄ 2g/L、(NH₄)₂SO₄ 15g/L、MgSO₄·7H₂O 1g/L；FeSO₄·7H₂0.03g/L of O, 22g/L of propionic acid, 11g/L of glycerol and 15g/L of corn oil; the pH value is controlled to be 5.0-6.0, the temperature is 30 ℃, and the regulation and control of dissolved oxygen are not carried out.

After fermentation culture for 114h, the solution was taken out of the tank, and the content of 3-hydroxypropionic acid in the fermentation solution was measured by the method described in example 1, whereby the concentration of 3-hydroxypropionic acid was 49.29 g/L.

Comparative example 2

The only difference from example 1 is that the fermentation medium is not fed with a feed, and all the fermentation medium components are added at once, i.e. the fermentation medium is: 33g/L of glucose, 10g/L of yeast extract, 5g/L of yeast powder and 3g/L, KH g of soybean meal₂PO₄ 5g/L、K₂HPO₄ 2g/L、(NH₄)₂SO₄ 15g/L、MgSO₄·7H₂O 1g/L；FeSO₄·7H₂0.03g/L of O, 22g/L of propionic acid, 11g/L of glycerol and 15g/L of corn oil.

After fermentation culture for 114h, the solution was taken out of the tank, and the content of 3-hydroxypropionic acid in the fermentation solution was measured by the method of example 1, whereby the concentration was 52.71 g/L.

Comparative example 3

The difference from example 1 is only that the second stage feeding operation is not supplemented with corn oil, and the set dissolved oxygen amount is achieved by increasing the rotation speed.

After fermentation culture for 114h, the solution was taken out of the tank, and the content of 3-hydroxypropionic acid in the fermentation solution was measured by the method described in example 1, whereby the concentration was 55.03 g/L.

The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solutions of the present invention can be made by those skilled in the art without departing from the spirit of the present invention, and the technical solutions of the present invention are within the scope of the present invention defined by the claims.