Selective heated extraction of proteins from intact freshwater algal cells

• US 8,476,412 B2
• Filed: 04/06/2011
• Issued: 07/02/2013
• Est. Priority Date: 04/06/2010
• Status: Expired due to Fees

• Current Assignee: Heliae Development, LLC (PT Perusahaan Perkebunan London Sumatra Indonesia Tbk)
• Original Assignee: Heliae Development, LLC (PT Perusahaan Perkebunan London Sumatra Indonesia Tbk)
• Inventors: Kale, Aniket
• Primary Examiner(s): Noakes, Suzanne M
• Assistant Examiner(s): Lee, Jae W
• Application Number:
  US13/081,204
• Publication Number:
  US 20110196131A1
• Time in Patent Office: 818 Days
• Field of Search: None
• US Class Current: 530/412
• CPC Class Codes: A61P 7/00 Drugs for disorders of the blood or the extracellular fluid
• CPC Class Codes: B01D 11/04 of solutions which are liquid
• CPC Class Codes: C11B 1/10 by extracting
• CPC Class Codes: C11B 1/108 after-treatment, e.g. of miscellae
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel

Abstract

Methods for selective extraction and fractionation of algal proteins from an algal biomass or algal culture are disclosed. A method of selective removal of products from an algal biomass provides for single and multistep extraction processes which allow for efficient separation of algal proteins. These proteins can be used as renewable sources of proteins for animal feedstocks and human food. Further, lipids remaining in the algal biomass after extraction of proteins can be used to generate renewable fuels.

Claims

1. A method of selectively removing algal proteins from a freshwater algal biomass or freshwater algal culture comprised of intact algal cells, the method comprising:

a. heating and mixing the freshwater algal biomass or freshwater algal culture, to generate a first heated extraction mixture, comprised of a first liquid fraction and a first biomass fraction;

b. separating the first liquid fraction from the first biomass fraction;

c. mixing the first biomass fraction with salt water and heating the resulting mixture to generate a second heated extraction mixture, comprised of a second liquid fraction and a second biomass fraction;

d. separating the second liquid fraction from the second biomass fraction;

e. mixing the second biomass fraction with water and heating to generate a third heated extraction mixture, comprised of a third liquid fraction and a third biomass fraction;

f. raising the pH of the third heated extraction mixture;

g. separating the third liquid fraction from the third biomass fraction;

h. mixing the third biomass fraction with an amphipathic solvent set and heating to generate a fourth heated extraction mixture comprised of a fourth liquid fraction and a fourth biomass fraction; and

i. separating the fourth liquid fraction from the fourth biomass fraction, wherein the first liquid fraction has a higher albumin protein concentration than the second, third, and fourth liquid fractions, the second liquid fraction has a higher globulin protein concentration than the first, third, and fourth liquid fractions, the third liquid fraction has a higher glutelin protein concentration than the first, second, and fourth liquid fractions, and the fourth liquid fraction has a higher prolamin protein concentration than the first, second, and third liquid fractions.

2. The method of claim 1, wherein one or more of the separating steps are performed by centrifugation, filtration, flotation, sedimentation, or any combination thereof.

3. The method of claim 1, wherein at least one of the first, second, third, and fourth heated extraction mixtures is maintained at a heated temperature below its boiling point prior to separating.

4. The method of claim 3, wherein at least one of the first, second, third, and fourth heated extraction mixtures is maintained at a heated temperature for between about 20 to about 60 minutes prior to separating.

5. The method of claim 1, wherein the fourth biomass fraction is enriched in lipids.

6. The method of claim 1, wherein the solvent set comprises ethanol.

7. The method of claim 1, wherein the solvent set comprises an alcohol.

8. The method of claim 1, further comprising recovering the albumin protein from the first liquid fraction.

9. The method of claim 1, further comprising recovering the globulin protein from the second liquid fraction.

10. The method of claim 1 further comprising recovering the glutelin protein from the third liquid fraction.

11. The method of claim 1 further comprising recovering the prolamin protein from the fourth liquid fraction.

12. The method of claim 1, wherein the first, second, third, or fourth extraction mixture is under a pressure greater than or equal to atmospheric pressure.