Method for producing basic substance

Patent metadata

Field	Value
Publication number	US-9334512-B2
Application number	US-201414483611-A
Country	US
Kind code	B2
Filing date	Sep 11, 2014
Priority date	Oct 7, 2004
Publication date	May 10, 2016
Grant date	May 10, 2016

Abstract

A method for producing a basic substance by fermentation comprising culturing a microorganism having an ability to produce the basic substance in a liquid medium contained in a fermentation tank to produce and accumulate the basic substance in the medium, wherein amount of sulfate and/or chloride ions used as counter ions of the basic substance is reduced by adjusting total ammonia concentration in the medium to be within a specific concentration range during at least a part of the total period of culture process.

First claim

What is claimed is:

1. A method for producing a basic amino acid by fermentation comprising culturing a microorganism having an ability to produce the basic amino acid in a liquid medium contained in a fermentation tank to produce and accumulate the basic amino acid in the medium;
wherein the amount of sulfate and/or chloride ions used as counter ions of the basic amino acid is reduced by adjusting the total ammonia concentration in the medium to be 300 mM or lower during at least a part of the total period of the culture process including a period where the pH of the medium increases due to shortage of the counter ions caused by accumulation of the objective basic amino acid;
wherein the total ammonia concentration in the medium is adjusted so to ensure growth of the microorganism or the production of the basic amino acid, and at said concentration does not inhibit the production of the basic amino acid by the microorganism; and
wherein the microorganism is an Escherichia coli bacterium or a coryneform bacterium.

2. The method according to claim 1 , wherein the total ammonia concentration in the medium is adjusted by adding ammonia or urea to the medium when an activity of the microorganism is reduced or ceases as determined based on the indicators: dissolved oxygen concentration in the medium, consumption rate of carbon source in the medium, turbidity of the medium, productivity of the basic amino acid, and pH change in the medium.

3. The method according to claim 1 , wherein the medium comprises sulfate ions and/or chloride ions as a counter ion source of the basic amino acid in an amount sufficient for performing the culture at pH 7.2 or lower except that amount of sulfate ions and/or chloride ions is reduced by a desired amount, and the at least a part of the total period is a period where the pH of the medium cannot be maintained to be 7.2 or lower due to a shortage of counter ions for the basic amino acid which has accumulated in the medium.

4. The method according to claim 1 , wherein the total ammonia concentration in the medium is adjusted to be 200 mM or lower.

5. The method according to claim 1 , wherein the total ammonia concentration in the medium is adjusted to be 100 mM or lower.

6. The method according to claim 1 , which comprises a step of proliferating the microorganism.

7. The method according to claim 6 , wherein the total ammonia concentration is not adjusted during the step of proliferating the microorganism.

8. The method according to claim 1 , wherein the basic amino acid is selected from the group consisting of L-lysine, L-arginine and L-histidine.

9. The method according to claim 8 , wherein the basic amino acid is L-lysine.

10. The method according to claim 8 , wherein the basic amino acid is L-arginine.

11. The method according to claim 1 , wherein the medium or a processed product thereof is heated after the culturing to eliminate bicarbonate ions and carbonate ions.

12. The method according to claim 1 , wherein said method results in a product selected from the group consisting of a fermentation broth, a dried product thereof, and products obtained by processing the fermentation broth or dried product thereof.

13. The method according to claim 1 , wherein the coryneform bacterium is Corynebacterium or Brevibacterium.

Assignees

• Ajinomoto Kk

Inventors

• Takeshita Ryo
• Sugimoto Shinichi

Classifications

• C12P13/24

  Proline; Hydroxyproline; Histidine · CPC title

• C12P13/20

  Aspartic acid; Asparagine · CPC title

• C12P13/10 Primary

  Citrulline; Arginine; Ornithine · CPC title

• C12P13/08

  Lysine; Diaminopimelic acid; Threonine; Valine · CPC title

• C12N1/20

  Bacteria; Culture media therefor · CPC title