Algae-based bioplastics and methods of making

Patent metadata

Field	Value
Publication number	US-12221604-B2
Application number	US-202318210234-A
Country	US
Kind code	B2
Filing date	Jun 15, 2023
Priority date	Oct 9, 2017
Publication date	Feb 11, 2025
Grant date	Feb 11, 2025

Abstract

Provided for are methods of producing triacylglycerol-accumulated microalgae, methods for making bioplastics from triacylglycerol-accumulated microalgae, methods for making alga-mixed plastics, and products including these bioplastics. Methods of triacylglycerol accumulation using centrifugation are also provided. Products such as plastic beads and other consumer products can be made from the bioplastics described herein.

First claim

I claim:

1. A method for making bioplastics comprising:
culturing a biomass comprising one or more genus of microalgae, wherein at least one of the genera is a triacylglycerol-accumulating microalgae;
centrifuging the microalgae during a stationary phase of culturing to induce polymer compound accumulation;
extracting a non-triacylglycerol accumulated polymer compound from a precipitate formed during centrifugation;
incubating and dehydrating the precipitate;
grinding the precipitate to form a powder and mixing with water to form a mixture; and
adding at least one additive to form the bioplastic, wherein the additive is selected from the group consisting of: an oxidizer; a plasticizer; and a combination thereof.

2. The method of claim 1 , wherein the microalgae comprises Chlamydomonas.

3. The method of claim 2 , wherein the microalgae further comprises Chlorella.

4. The method of claim 3 , wherein triacylglycerol-accumulating microalgae is Chlamydomonas reinhardtii , and the Chlorella is Chlorella vulgaris;
wherein the accumulated polymer compound is produced by Chlorella vulgaris ; and
wherein the accumulated polymer compound is selected from starch, triglyceride, cellulose, proteins, and a combination thereof.

5. The method of claim 2 , further comprising cross-linking the Chlamydomonas.

6. The method of claim 3 , further comprising cross-linking the Chlamydomonas with the Chlorella.

7. The method of claim 1 , wherein the oxidizer comprises ammonium persulfate, hydrogen peroxide, sodium persulfate, or a combination thereof.

8. The method of claim 1 , wherein the plasticizer comprises polyethylene, glycerol, or a combination thereof.

9. The method of claim 1 , wherein the additive is from about 5% weight per dry weight (w/dw) to about 15% w/dw of the biomass.

10. The method of claim 1 , wherein the method further comprises eluting carotenoids from supernatant generated during the centrifugation.

11. The method of claim 1 , wherein the non-triacylglycerol accumulated polymer compound is a carotenoid.

12. The method of claim 1 , wherein the centrifugation forms a triacylglycerol-accumulated Chlamydomonas comprising about 38 to 72 μg of triacylglycerol per 10 6 cells and about 1% (mol/mol) or less of unsaturated C18 fatty acids in a total amount of the triacylglycerol.

13. A method for making bioplastics comprising:
culturing a biomass comprising one or more genus of microalgae, wherein at least one of the genera is a triacylglycerol-accumulating microalgae;
centrifuging the microalgae during a stationary phase of culturing to induce polymer compound accumulation;
extracting precipitate formed during centrifugation;
incubating and dehydrating the precipitate;
grinding the precipitate to form a powder and mixing with water to form a mixture;
adding at least one additive to the mixture to form the bioplastic;
wherein the additive is selected from an oxidizer, a plasticizer, and a combination thereof;

heating the mixture to about 120° C.; and
molding the mixture into a shape.

14. The method of claim 13 , wherein the microalgae comprises Chlamydomonas.

15. The method of claim 14 , further comprising Chlorella.

16. The method of claim 14 , wherein the Chlamydomonas is Chlamydomonas reinhardtii.

17. The method of claim 16 , further comprising Chlorella vulgaris , wherein during centrifugation, the Chlorella vulgaris accumulates a polymer selected from starch, triglyceride, cellulose, proteins, and a combination thereof.

18. The method of claim 13 , wherein the additive is selected from the group consisting of: ammonium persulfate; hydrogen peroxide; sodium persulfate; polyethylene; glycerol; and a combination thereof.

19. The method of claim 13 , wherein the additive is from about 5% w/dw to about 15% w/dw of the biomass.

20. The method of claim 13 , wherein the method further comprises eluting carotenoids from supernatant generated during the centrifugation.

Assignees

• Univ Louisiana State

Inventors

• Kato Naohiro

Classifications

• C12P7/6463

  obtained from glyceride producing microorganisms, e.g. single cell oil · CPC title

• C08L99/00

  Compositions of natural macromolecular compounds or of derivatives thereof not provided for in groups C08L89/00 - C08L97/00 · CPC title

• C08H99/00

  Subject matter not provided for in other groups of this subclass {, e.g. flours, kernels} · CPC title

• A01G33/00

  Cultivation of seaweed {or algae} · CPC title

• A01H13/00

  Algae (unicellular algae C12N1/12) · CPC title