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

• US 8,124,384 B2
• Filed: 05/08/2007
• Issued: 02/28/2012
• 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, Mirrasoul, Peter J., Ruecker, Craig M., Kaneko, Tatsuo, Hansen, John M., Veeder, George T. III, Barclay, William R.
• Primary Examiner(s): Afremova, Vera
• Application Number:
  US11/745,506
• Publication Number:
  US 20080032363A1
• Time in Patent Office: 1,757 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 growing microorganisms of the order Thraustochytriales by conducting a fermentation of the microorganisms in a fermentation medium comprising a carbon source and a limiting nutrient source, the process comprising:

a) providing the fermentation medium comprising the carbon source and the limiting nutrient source;

b) adding the microorganisms to the fermentation medium;

c) adding an additional amount of the carbon source and limiting nutrient source to the fermentation medium to increase the biomass density of the fermentation medium to at least about 100 g/L on a dry cell weight basis, wherein the additional amount of the carbon source and the limiting nutrient source are added at a rate sufficient to increase the biomass density of the fermentation medium to at least 100 g/L;

d) adding an additional amount of the carbon source while limiting the amount of limiting nutrient source added to the formulation medium to induce lipid production by the microorganisms; and

e) recovering at least some of the lipids from the microorganisms;

wherein the primary use of the carbon source by the microorganisms is to produce lipids after induction of lipid production,

wherein the microorganisms produce lipids containing polyunsaturated fatty acids when the biomass density is at least 100 g/L on a dry cell weight basis, and

wherein the microorganisms produce at least 20% by weight of the dry cell weight of the biomass as lipids.

2. The process of claim 1, wherein the process is a fed-batch process.

3. The process of claim 1, wherein the fermentation of the microorganisms produces lipids containing polyunsaturated fatty acids when the biomass density of the fermentation medium is at least 150 g/L on a dry cell weight basis.

4. The process of claim 1, wherein the process produces lipids at an average rate of at least 0.5 grams lipids per liter of fermentation medium per hour feimentation.

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

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

13. The process of claim 1 or 7, wherein the microorganisms are Schizochytrium.

7. A process for producing microbial lipids comprising:

a) growing microorganisms of the order Thraustochytriales in a fertmentation medium to increase the biomass density of the fermentation medium;

b) inducing lipid production when the biomass density of the fermentation medium is at least 100 g/L on a dry cell weight basis; and

c) recovering the lipids from the fermentation medium, wherein greater than 15% of the lipids are polyunsaturated lipids.

8. The process of claim 7, wherein the process is a fed-batch process.

9. The process of claim 7, wherein after inducing lipid production, the biomass density of the fermentation medium is at least 150 g/L on a dry cell weight basis.

10. The process of claim 7, wherein the process produces lipids at an average rate of at least 0.5 grams lipids per liter of fermentation medium per hour fermentation.

11. The process of claim 7, wherein the microorganisms are selected from the group consisting of Thraustochytrium, Schizochytrium, and mixtures thereof.

12. The process of claim 7, wherein the process produces on average at least 0.2 grams docosahexaenoic acid per liter of fermentation medium per hour fermentation.