Solventless extraction process

• US 20040229325A1
• Filed: 02/20/2004
• Published: 11/18/2004
• Est. Priority Date: 01/19/2000
• Status: Active Grant

• Current Assignee: DSM IP Assets BV (DSM-Firmenich AG)
• Original Assignee: Martek Biosciences Corporation (DSM-Firmenich AG)
• Inventors: Ruecker, Craig M., Veeder, George T. III, Engelhardt, Brian S., Adu-peasah, Swithin Patrick
• Granted Patent: US 7,351,558 B2
• Time in Patent Office: Days
• US Class Current: 435/134
• CPC Class Codes: C11B 1/02 Pretreatment
• CPC Class Codes: C11B 3/001 by a combination of two or more of the means hereafter
• CPC Class Codes: C11B 3/006 by extraction
• CPC Class Codes: C12N 1/06 Lysis of microorganisms
• CPC Class Codes: C12P 23/00 Preparation of compounds containing a cyclohexene ring having an unsaturated side chain containing at least ten carbon atoms bound by conjugated double bonds, e.g. carotenes containing heterorings C12P17/00
• CPC Class Codes: C12P 25/00 Preparation of compounds containing alloxazine or isoalloxazine nucleus, e.g. riboflavin
• CPC Class Codes: C12P 33/00 Preparation of steroids
• 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 7/6463 obtained from glyceride producing microorganisms, e.g. single cell oil
• CPC Class Codes: C12P 7/6472 containing polyunsaturated fatty acid [PUFA] residues, i.e. having two or more double bonds in their backbone

Abstract

The present invention provides a method for extracting lipids from microorganisms without using organic solvent as an extraction solvent. In particular, the present invention provides a method for extracting lipids from microorganisms by lysing cells and removing water soluble compound and/or materials by washing the lysed cell mixtures with aqueous washing solutions until a substantially non-emulsified lipid is obtained.

Claims

1. A process for obtaining lipid from microorganisms comprising:

a) lysing cells of the microorganisms to produce a lysed cell mixture;

b) treating said lysed cell mixture to produce a phase separated mixture comprising a heavy layer and a light layer, wherein said heavy layer comprises an aqueous solution and said light layer comprises said lipid;

c) separating said heavy layer from said light layer; and

d) obtaining said lipid from said light layer.

2. The process of claim 1, wherein said step (b) comprises centrifuging said lysed cell mixture.

3. The process of claim 2, wherein said light layer comprises an emulsified lipid.

4. The process of claim 3 further comprising:

e) adding an aqueous extraction solution to said light layer of step (c); and

f) repeating said steps (b), (c) and (e) until said lipid becomes substantially non-emulsified prior to said step (d).

11. The process of claim 1, wherein said step (a) comprises heating said microorganisms to temperature of at least about 50°

C.

12. The process of claim 1, wherein said microorganism is capable of growth at salinity level of less than about 12 g/L of sodium chloride.

14. The process of claim 1, wherein said microorganism is selected from the group consisting of algae, fungi, bacteria and protist.

15. The process of claim 14, wherein said microorganisms comprise microorganisms of the order Thraustochytriales.

18. The process of claim 1, wherein said microorganisms are capable of producing at least about 0.1 grams per liter per hour of docosahexaenoic acid.

19. The process of claim 1, wherein at least about 30% of said lipid is docosahexaenoic acid.

5. (Cancelled)

6. (Cancelled)

7. (Cancelled)

8. The process of claim 7 further comprising adding a base to a fermentation broth.

10. The process of claim 7 further comprising solubilizing at least part of proteinaceous compounds in a fermentation broth.

9. (Cancelled)

13. (Cancelled)

16. (Cancelled)

17. (Cancelled)

20. A process for obtaining lipids from microorganisms comprising:

a) growing said microorganisms in a fermentation medium to produce a fermentation broth;

b) solubilizing at least a part of any proteins present in said fermentation broth;

c) lysing cells of said microorganisms to produce a lysed cell mixture;

d) treating said lysed cell mixture to produce a phase separated mixture comprising a heavy layer and a light layer, wherein said heavy layer comprises an aqueous solution and said light layer comprises emulsified lipids;

e) separating said heavy layer from said light layer; and

f) obtaining said lipids from said light layer.

21. The process of claim 20, wherein said step of dissolving proteins comprises contacting said fermentation broth with a base.

23. The process of claim 20, wherein said step of lysing cells comprises heating said microorganisms to a temperature of at least about 50°

C.

24. The process of claim 20, wherein said step of producing the phase separated mixture comprises centrifuging said lysed cell mixture.

25. The process of claim 20, wherein said step of obtaining said lipids from said light layer comprises:

(A) adding an aqueous washing solution to said light layer;

(B) separating said aqueous washing solution from said light layer; and

(C) repeating said steps (A) and (B) until said lipid becomes substantially non-emulsified.

22. (Cancelled)

26-34. -34. (Cancelled)

35. A process for obtaining lipids from microorganisms comprising:

a) growing said microorganisms in a fermentation medium to produce a fermentation broth;

b) contacting said fermentation broth with a base to dissolve at least a part of any proteins present in said fermentation broth;

c) increasing the temperature of said fermentation broth to at least about 50°

C. to lyse cells of said microorganisms to produce a lysed cell mixture;

d) separating substances of different densities from said lysed cell mixture to produce a phase separated mixture comprising a heavy layer and a light layer, wherein said heavy layer comprises an aqueous solution and said light layer comprises emulsified lipids;

e) removing said heavy layer from said phase separated mixture;

f) adding an aqueous washing solution to said light layer;

g) separating substances of different densities from said mixture of step (f);

h) removing said heavy layer from said phase separated mixture; and

i) repeating said steps (f)-(h) until said lipid becomes substantially non-emulsified.

36. The process of claim 35, wherein said base is selected from the group consisting of hydroxides, carbonates, bicarbonates, and mixtures thereof.

37. The process of claim 35, wherein said step of producing the phase separated mixture comprises centrifuging said lysed cell mixture.

38-46. -46. (Cancelled)