Process for the heterotrophic production of microbial products with high concentrations of omega-3 highly unsaturated fatty acids

• US 20060188969A1
• Filed: 04/18/2006
• Published: 08/24/2006
• Est. Priority Date: 09/07/1988
• Status: Abandoned Application

• Current Assignee: DSM IP Assets BV (DSM-Firmenich AG)
• Original Assignee: Martek Biosciences Corporation (DSM-Firmenich AG)
• Inventors: Barclay, William R.
• Application Number:
  US11/406,995
• Publication Number:
  US 20060188969A1
• Time in Patent Office: Days
• US Class Current: 435/169
• CPC Class Codes: C12P 7/6427 Polyunsaturated fatty acids [PUFA], i.e. having two or more double bonds in their backbone
• CPC Class Codes: C12P 7/6432 Eicosapentaenoic acids [EPA]
• CPC Class Codes: C12P 7/6434 Docosahexenoic acids [DHA]
• CPC Class Codes: C12P 7/6472 containing polyunsaturated fatty acid [PUFA] residues, i.e. having two or more double bonds in their backbone

Abstract

A process for the heterotrophic or predominantly heterotrophic production of whole-celled or extracted microbial products with a high concentration of omega-3 highly unsaturated fatty acids, producible in a aerobic culture under controlled conditions using biologically pure cultures of heterotrophic single-celled fungi microorganisms of the order Thraustochytriales. The harvested whole-cell microbial product can be added to processed foods as a nutritional supplement, or to fish and animal feeds to enhance the omega-3 highly unsaturated fatty acid content of products produced from these animals. The lipids containing these fatty acids can also be extracted and used in nutritional, pharmaceutical and industrial applications.

Claims

1. A method of producing omega-3 HUFAs, comprising culturing Thraustochytriales in a medium comprising a source of organic carbon and a source of assimilable nitrogen.

2. A method, as claimed in claim 1, wherein said Thraustochytriales are selected from the group consisting of Thraustochytrium, Schizochytrium, and mixtures thereof.

3. A method, as claimed in claim 2, further comprising culturing said Thraustochytrium, Schizochytrium, or mixtures thereof under nutrient-limited conditions for an effective amount of time, preferably about 6 to 24 hours.

4. A method, as claimed in claim 1, further comprising adding to said omega-3 HUFAs or said Thraustochytriales during post-harvest processing of said omega-3 HUFAs or said Thraustochytriales a compound selected from the group consisting of BHT, BHA, TBHQ, ethoxyquin, beta-carotene, vitamin E and vitamin C.

5. A method, as claimed in claim 1, wherein said culturing step further comprises limiting the concentration in the medium of said source of assimilable nitrogen and harvesting said Thraustochytriales during said nitrogen limitation.

6. A method, as claimed in claim 2, further comprising stressing said Thraustochytrium, Schizochytrium, or mixtures thereof with low temperatures during culturing.

7. A method, as claimed in claim 1, further comprising maintaining a high dissolved oxygen concentration in said medium during culturing.

8. A method, as claimed in claim 2, wherein said medium further comprises an effective amount of phosphorous to provide sustained growth of said Thraustochytrium, Schizochytrium, or mixtures thereof.

9. A method, as claimed in claim 2, wherein said medium further comprises an effective amount of microbial growth factor to provide sustained growth of said Thraustochytrium, Schizochytrium, or mixtures thereof.

10. A method, as claimed in claim 9, wherein said microbial growth factor comprises yeast extract.

11. A method, as claimed in claim 9, wherein said microbial growth factor comprises corn steep liquor.

12. A method of producing omega-3 HUFAs, as claimed in claim 1, further comprising extracting lipids from said Thraustochytriales.

13. A method, as claimed in claim 12, further comprising fractional crystallization of the extracted lipids to separate omega-3 HUFAs therefrom.

14. A method, as claimed in claim 13, wherein said fractional crystallization comprises the steps of:

a. rupturing microorganism cells to yield ruptured cells;

b. solvent extracting a lipid mixture from the ruptured cells;

c. hydrolyzing the lipid mixture;

d. cold-crystallizing non-HUFAs in said lipid mixture.

15. A method, as claimed in claim 14, further comprising removing non-saponifiable compounds from said lipid mixture prior to said cold-crystallization.

16. A method, as claimed in claim 1, wherein said carbon source and said nitrogen source comprise ground grain.

17. A method of producing omega-3 HUFAs, comprising culturing Thraustochytrium in a medium comprising ground grain.