Coordinated-control coenzyme Q10 fermentation production process based on online oxygen consumption rate and electrical conductivity

Patent metadata

Field	Value
Publication number	US-10982242-B2
Application number	US-201615757936-A
Country	US
Kind code	B2
Filing date	Oct 21, 2016
Priority date	Oct 26, 2015
Publication date	Apr 20, 2021
Grant date	Apr 20, 2021

Abstract

The present invention relates to an optimized fermentation process of coenzyme Q10, particularly to a fermentation process of coenzyme Q10 via flow feeding based on cooperative control of changes of online oxygen consumption rate and conductivity. During the fermentation process of coenzyme Q10 production strains, the oxygen consumption rate is controlled between 30-150 mmol/L·h and the conductivity is maintained between 3.0-30.0 ms/cm via flow feeding, so as to facilitate strain growth and the start of coenzyme Q10 synthesis and accumulation. The present invention can substantially increase output of coenzyme Q10 and greatly reduce the production cost with simple process control and strong operability, thus being applicable to large-scale industrial production.

First claim

The invention claimed is:

1. A fermentation process for producing coenzyme Q10 by coordinated-control of an oxygen-consumption rate and electrical conductivity of a fermentation culture, comprising the steps of:
(i) providing a culture medium and coenzyme Q10-production microorganisms in a fermentation tank to obtain the fermentation culture;
(ii) controlling the oxygen-consumption rate of the fermentation culture at a level between 30-90 mmol/L-h during the fermentation process; and
(iii) controlling the conductivity of the fermentation culture at a level between 5.0-30.0 ms/cm during the fermentation process, so as to facilitate growth of the microorganisms and initiation of coenzyme Q10 synthesis and accumulation;
wherein the controlling of the oxygen-consumption rate is conducted online;
wherein the fermentation process further comprises: inoculation of the microorganisms obtained from seed cultivation into the fermentation tank containing the fermentation culture, cultivation of the microorganisms under appropriate fermentation conditions, detection of the oxygen consumption rate and conductivity of the fermentation culture during the cultivation, and adjustment of fermentation conditions based on detection results;
wherein the oxygen consumption rate is adjusted via an agitation speed of the fermentation culture and air flow, and the fermentation process comprises the following stages and steps:
(1) during 0-24th hour, controlling the agitation speed of the fermentation culture at 400 rpm and air flow at 9 L/min, wherein the oxygen consumption rate increases rapidly and keeps at 30-50 mmol/L-h, and the conductivity decreases to 7-16 ms/cm;
(2) during 24-36th hour, increasing the agitation speed to 450 rpm and keeping the air flow at 9 L/min, wherein the oxygen consumption rate is 50-60 mmol/L-h;
(3) during 36-60th hour, keeping the agitation speed at 450 rpm and increasing the air flow to 16 L/min, wherein the oxygen consumption rate is 60-70 mmol/L-h;
(4) during 60-90th hour, keeping the agitation speed at 450 rpm and increasing the air flow to 20 L/min, wherein the oxygen consumption rate is 70-90 mmol/L-h;
(5) during 90-100th hour, controlling the agitation speed at 400 rpm, wherein the oxygen consumption rate is 70-90 mmol/L-h;
(6) after 100th hour, controlling the air flow at 16 L/min, wherein the oxygen consumption rate is 50-60 mmol/L-h;
keeping the conductivity of the fermentation culture between 10-20 ms/cm in stages (2)-(6);
(iv) collecting microbial cells in the fermentation culture through solid-liquid separation;
(v) extracting coenzyme Q10 from the microbial cells with an organic solvent; and wherein the coenzyme Q10-production microorganisms are Rhodobacter sphaeroides.

2. The fermentation process for producing coenzyme Q10 according to claim 1 , characterized in that the conductivity is adjusted in the manner of flow feeding or batch-feeding of a feeding culture medium.

3. The fermentation process for producing coenzyme Q10 according to claim 2 , characterized in that a formula of the feeding culture medium used in the flow feeding or batch-feeding is as follows: in 1 L feeding culture medium, there are 8-12 g of yeast powder, 5-10 g of ammonium sulfate, 1-2 g of magnesium sulfate, 3-6 g of sodium chloride, 2-4 g of monopotassium phosphate, 2-4 g of dipotassium phosphate, 1-2 g of calcium chloride and 0.013-0.025 g of biotin with pH value of 7.0; and the conductivity of the feeding culture medium is 13.5-23 ms/cm.

4. The fermentation process for producing coenzyme Q10 according to claim 1 , characterized in that the coenzyme Q10-production microorganisms are Rhodobacter sphaeroides strains selected from the group consisting of strains from natural selection, strains selected via physical or chemical mutagenesis, and high-producing strains reconstructed with genetic engineering approach.

5. The fermentation process for producing coenzyme Q10 according to claim 1 , characterized in that the coenzyme Q10-production microorganisms are Rhodobacter sphaeroides strain CGMCC No. 5997, or Rhodobacter sphaeroides strain CGMCC No. 5998, or Rhodobacter sphaeroides strain CGMCC No. 5999.

6. The fermentation process for producing coenzyme Q10 according to claim 1 , characterized in that a volume of the fermentation tank is 10 L-150 m 3 .

Assignees

• Shangyu Nhu Biological Chemical Co Ltd
• Univ Zhejiang
• Zhejiang Nhu Co Ltd

Inventors

• Yu Hongwei
• Lv Yong
• Li Yong
• Chen Jianbo
• Chen Shaofeng
• Li Weifeng
• Zhang Hongmei
• Zhu Yongqiang

Classifications

• C12N1/20

  Bacteria; Culture media therefor · CPC title

• C12R2001/01

  Bacteria or Actinomycetales {; using bacteria or Actinomycetales} · CPC title

• C12N1/205

  Bacterial isolates · CPC title

• C12P7/66 Primary

  containing the quinoid structure · CPC title

• C12Q3/00

  Condition responsive control processes (apparatus therefor C12M1/36; controlling or regulating in general G05) · CPC title