Production of high levels of DHA in microalgae using modified amounts of chloride and potassium

Patent metadata

Field	Value
Publication number	US-9249434-B2
Application number	US-201414165459-A
Country	US
Kind code	B2
Filing date	Jan 27, 2014
Priority date	Oct 2, 2003
Publication date	Feb 2, 2016
Grant date	Feb 2, 2016

Abstract

Methods for production of highly unsaturated fatty acids by marine microorganisms, including the heterotrophic marine dinoflagellate Crypthecodinium , using low levels of chloride ion are disclosed. Specifically, methods of increasing production of highly unsaturated fatty acids by marine microorganisms while growing in low chloride media by manipulating sodium ion and potassium ion levels. The invention also relates to methods of production of highly unsaturated fatty acids by marine organisms at low pH levels, and includes methods for generation of low pH tolerant strains.

First claim

We claim:

1. A method of producing a biomass comprising docosahexaenoic acid (DHA), comprising:
culturing a heterotrophic microalga in a culture medium to produce said biomass, wherein the culture medium comprises:
chloride ions at a concentration of less than or equal to 2 g/L;
potassium ions at a concentration of greater than or equal to 0.5 g/L; and
a pH less than or equal to 4.5; and
recovering the DHA-containing biomass from the microalga.

2. The method of claim 1 , wherein the concentration of chloride ions is less than or equal to 1 g/L.

3. The method of claim 1 , wherein the concentration of chloride ions is less than or equal to 0.3 g/L.

4. The method of claim 1 , wherein the culture medium further comprises sodium ions at a concentration of 1 g/L to 8 g/L.

5. The method of claim 1 , wherein the culture medium further comprises sodium ions at a concentration of 1.5 g/L to 5 g/L.

6. The method of claim 1 , wherein the pH is 4.5.

7. The method of claim 1 , wherein a source of potassium comprises potassium sulfate.

8. The method of claim 1 , wherein microalga produces at least 0.04 g DHA per 10 9 cells.

9. The method of claim 1 , wherein the microalga produces at least 0.10 g DHA per 10 9 cells.

10. The method of claim 1 , wherein the microalga produces at least 0.20 g DHA per 10 9 cells.

11. The method of claim 1 , wherein the culture medium further comprises sodium ions and wherein the ratio of sodium ions to potassium ions is less than or equal to 27:1.

12. The method of claim 1 , wherein the culture medium further comprises sodium ions and the ratio of sodium ion to potassium ion is less than or equal to 15:1.

13. The method of claim 1 , wherein the culture medium further comprises sodium ions and the ratio of sodium ion to potassium ion is less than or equal to 4:1.

14. The method of claim 1 , wherein the microalga is of the class Dinophyceae.

15. The method of claim 1 , wherein the microalga is of the genus Crypthecodinium.

16. The method of claim 1 , wherein the microalga is of the species Crypthecodinium cohnii.

Assignees

• Dsm Ip Assets Bv

Inventors

• Behrens Paul W
• Thompson John M
• Apt Kirk
• Pfeifer Joseph W
• Wynn James P
• Lippmeier James Casey
• Fichtali Jaouad
• Hansen Jon

Classifications

• C11B1/10

  by extracting · CPC title

• C12N1/12

  Unicellular algae; Culture media therefor (as new plants A01H13/00) · CPC title

• A61K36/02

  Algae · CPC title

• C12N2500/00

  Specific components of cell culture medium · CPC title

• C12N5/0018 Primary

  Culture media for cell or tissue culture (media for specific animal cell type C12N5/06) · CPC title