Structuring fats and methods of producing structuring fats
View Patent ↗Recombinant DNA techniques are used to produce oleaginous recombinant cells that produce triglyceride oils having desired fatty acid profiles and regiospecific or stereospecific profiles. Genes manipulated include those encoding stearoyl-ACP desturase, delta 12 fatty acid desaturase, acyl-ACP thioesterase, ketoacyl-ACP synthase, and lysophosphatidic acid acyltransferase. The oil produced can have enhanced oxidative or thermal stability, or can be useful as a frying oil, shortening, roll-in shortening, tempering fat, cocoa butter replacement, as a lubricant, or as a feedstock for various chemical processes. The fatty acid profile can be enriched in midchain profiles or the oil can be enriched in triglycerides of the saturated-unsaturated-saturated type.
1. A method of producing a triglyceride oil, the method comprising:
cultivating a recombinant microalgal cell expressing an exogenous polynucleotide encoding a ketoacyl-ACP synthase; and
extracting the oil produced by the cell;
wherein the triglyceride oil is enriched in stearic-oleic-stearic triglyceride as compared to a non-recombinant microalgal cell.
2. The method of claim 1 , wherein the microalgal cell is a cell of the genus Prototheca or Chlorella.
3. The method of claim 2 , wherein the microalgal cell is a Prototheca moriformis cell.
4. The method of claim 1 , wherein the recombinant microalgal cell further comprises an exogenous polynucleotide that encodes a fatty acyl-ACP thioesterase.
5. The method claim 1 , wherein the recombinant microalgal cell further comprises nucleic acids operable to reduce the expression of stearoyl-ACP desaturase or a fatty acyl desaturase.
6. The method of claim 5 , wherein the nucleic acids operable to reduce the expression of a stearoyl-ACP desaturase or a fatty acyl desaturase is a nucleic acid that encodes an RNA construct that reduces the activity of stearoyl-ACP desaturase or the fatty acyl desaturase.
7. The method of claim 1 , wherein the oil is enriched in triglycerides of the saturated-unsaturated-saturated type, wherein the sum of palmitic-oleic-palmitic, stearic-oleic-stearic and palmitic-oleic-stearic is at least 30% of the triglycerides.
8. The method of claim 7 , wherein the sum of palmitic-oleic-palmitic, stearic-oleic-stearic and palmitic-oleic-stearic is at least 50% of the triglycerides.
9. The method of claim 8 , wherein the oil comprises triglycerides comprising at least 50% stearic-oleic-stearic, and optionally less than 10% stearic-stearic-stearic.
10. The method of claim 1 , wherein the recombinant microalgal cell further comprises an exogenous sucrose invertase gene so that the cell can grow on sucrose as a sole carbon source.
11. A method of producing a triglyceride oil, the method comprising:
cultivating a recombinant microalgal cell expressing an exogenous polynucleotide encoding a ketoacyl-ACP synthase and a fatty acyl-ACP thioesterase; and
extracting the oil produced by the cell;
wherein the triglyceride oil is enriched in stearic-oleic-stearic triglyceride as compared to a non-recombinant microalgal cell.
12. The method of claim 11 , wherein the microalgal cell is a cell of the genus Prototheca or Chlorella.
13. The method of claim 12 , wherein the microalgal cell is a cell of the genus Prototheca.
14. The method of claim 13 , wherein the microalgal cell is a Prototheca moriformis cell.
15. The method claim 11 , wherein the recombinant microalgal cell further comprises nucleic acids operable to reduce the expression of stearoyl-ACP desaturase or a fatty acyl desaturase.
16. The method of claim 11 , wherein the nucleic acids operable to reduce the expression of a stearoyl-ACP desaturase or a fatty acyl desaturase is a nucleic acid that encodes an RNA construct that reduces the activity of stearoyl-ACP desaturase or the fatty acyl desaturase.
17. The method of claim 11 , wherein the oil is enriched in triglycerides of the saturated-unsaturated-saturated type, wherein the sum of palmitic-oleic-palmitic, stearic-oleic-stearic and palmitic-oleic-stearic is at least 30% of the triglycerides.
18. The method of claim 17 , wherein the sum of palmitic-oleic-palmitic, stearic-oleic-stearic and palmitic-oleic-stearic is at least 50% of the triglycerides.
19. The method of claim 18 , wherein the oil comprises triglycerides comprising at least 50% stearic-oleic-stearic, and optionally less than 10% stearic-stearic-stearic.
20. The method of claim 11 , wherein the recombinant microalgal cell further comprises an exogenous sucrose invertase gene so that the cell can grow on sucrose as a sole carbon source.