Enhanced production of lipids containing polyenoic fatty acid by very high density cultures of eukaryotic microbes in fermentors

• US 8,216,812 B2
• Filed: 05/08/2007
• Issued: 07/10/2012
• Est. Priority Date: 01/28/2000
• Status: Expired due to Term

• Current Assignee: DSM IP Assets BV (DSM-Firmenich AG)
• Original Assignee: Martek Biosciences Corporation (DSM-Firmenich AG)
• Inventors: Bailey, Richard B., DiMasi, Don, Hansen, John M., Mirrasoul, Peter J., Ruecker, Craig M., Veeder, George T. III, Kaneko, Tatsuo, Barclay, William R.
• Primary Examiner(s): Afremova, Vera
• Application Number:
  US11/745,490
• Publication Number:
  US 20080032360A1
• Time in Patent Office: 1,890 Days
• Field of Search: None
• US Class Current: 435/134
• CPC Class Codes: A23D 9/00 Other edible oils or fats, e.g. shortenings, cooking oils
• CPC Class Codes: A23K 20/158 Fatty acids; Fats; Products containing oils or fats
• CPC Class Codes: A23K 50/80 for aquatic animals, e.g. fish, crustaceans or molluscs
• CPC Class Codes: A23L 29/065 Microorganisms addition of bacteria for nutritional purposes A23L33/135
• CPC Class Codes: A23V 2002/00 Food compositions, function of food ingredients or processes for food or foodstuffs
• CPC Class Codes: A61P 3/02 Nutrients, e.g. vitamins, minerals
• CPC Class Codes: C11B 1/10 by extracting
• CPC Class Codes: C12N 1/00 Microorganisms, e.g. protozoa; Compositions thereof medicinal preparations containing material from protozoa, bacteria or viruses A61K35/66, from algae A61K36/02, from fungi A61K36/06; preparing medicinal bacterial antigen or antibody compositions, e.g. bacterial vaccines, A61K39/00; Processes of propagating, maintaining or preserving microorganisms or compositions thereof; Processes of preparing or isolating a composition containing a microorganism; Culture media therefor
• CPC Class Codes: C12N 1/12 Unicellular algae; Culture media therefor as new plants A01H13/00
• CPC Class Codes: C12P 7/6409 Fatty acids
• 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
• CPC Class Codes: Y10S 435/911 using fungi

Abstract

The present invention provides a process for growing eukaryotic microorganisms which are capable of producing lipids, in particular lipids containing polyenoic fatty acids. The present invention also provides a process for producing eukaryotic microbial lipids.

Claims

1. A process for producing lipids containing polyunsaturated fatty acids from microorganisms of the order Thraustochytriales by conducting a fermentation of the microorganisms in a fermentation medium comprising a carbon source, the process comprising:

a) providing the fermentation medium comprising the carbon source at a temperature of at least 20°

C. and a pH of about 5 to about 11;

b) adding the microorganisms to the fermentation medium;

c) adding an additional amount of the carbon source to the fermentation medium in a fed-batch process to increase the biomass density of the fermentation medium to at least 100 g/L on a dry cell weight basis, wherein the additional amount of the carbon source is added at a rate sufficient to increase the biomass density of the fermentation medium to at least 100 g/L; and

d) recovering lipids from the fermentation medium;

wherein the primary use of the carbon source by the microorganisms is to produce the lipids when the biomass density of the fermentation medium is at least 100 g/L on a dry cell weight basis,

wherein the lipids contain polyunsaturated fatty acids, and

wherein the lipids are at least 20% of the biomass when the biomass density is at least 100 g/L.

2. The process of claim 1, wherein the process produces the lipids at an average rate of at least 0.5 g/L/hr.

3. The process of claim 1, wherein the microorganisms are selected from the group consisting of Thraustochytrium, Schizochytrium, and mixtures thereof.

4. The process of claim 1, wherein the process produces on average at least 0.2 g/L/hr of docosahexaenoic acid.

5. The process of claim 1, wherein the microorganisms are Schizochytrium.

6. The process of claim 1, wherein the carbon source comprises a carbohydrate.

7. The process of claim 1, wherein docosahexaenoic acid is at least 15% of the total lipids.

8. The process of claim 1, wherein the lipids are produced at an average rate of at least 0.5 grams per liter of fermentation medium per hour of the fermentation and wherein the total amount of omega-3 and omega-6 fatty acids is at least 20% of the lipids.

9. The process of claim 1, wherein the lipids are produced at an average rate of at least 0.5 grams per liter of fermentation medium per hour of the fermentation and wherein docosahexaenoic acid is at least 25% of the lipids.

10. The process of claim 1, wherein the microorganisms produce the lipids under aerobic conditions.

11. The process of claim 1, wherein dissolved oxygen in the fermentation medium is controlled.

12. The process of claim 1, wherein the process produces on average at least 0.2 grams of docosahexaenoic acid per liter of the fermentation medium per hour of the fermentation.

13. The process of claim 1, further comprising, removing water from the fermentation medium to provide dry microorganisms prior to recovering the lipids from the microorganisms, wherein at least 15% of the lipids are polyunsaturated fatty acids.

14. The process of claim 13, wherein the water is removed from the fermentation medium by evaporation without prior centrifugation to provide dry microorganisms prior to recovering the lipids from the microorganisms, wherein at least 15% of the microbial lipids are polyunsaturated fatty acids.