Immobilized enzymes and methods of using thereof

1. Immobilized enzyme comprising Candida antartica lipase B immobilized in a matrix, wherein the matrix comprises a copolymer of divinylbenzene and ethylvinylbenzene or styrene, wherein the matrix has at least 79 weight % divinylbenzene and 4 weight % or less non-polymerizable impurities, wherein the amount of lipase immobilized in the matrix is from 7.5 to 35 KLU/g matrix based on the difference in the enzyme concentration in the solution used to interact with the matrix as measured at 280 nm, and wherein a surfactant is not used in the preparation of the immobilized enzyme.

2. The immobilized enzyme of claim 1 , wherein the matrix comprises less than 2% by weight non-polymerizable impurities.

3. The immobilized enzyme of claim 1 , wherein enzyme is derived the matrix comprises a copolymer of divinylbenzene and styrene.

4. A method for transesterifying an ester, comprising reacting the ester with an alcohol in the presence of the immobilized enzyme of claim 1 , wherein the ester comprises an ester of an unsaturated fatty acid.

5. The method of claim 4 , wherein the unsaturated fatty acid is derived from fish oil.

6. The method of claim 4 , wherein the unsaturated fatty acid is an omega-3 fatty acid.

7. The method of claim 4 , wherein the unsaturated fatty acid is linoleic acid, linolenic acid, gamma-linolenic acid, arachidonic acid, mead acid, stearidonic acid, alpha-eleostearic acid, eleostearic acid, pinolenic acid, docosadienic acid, docosatetraenoic acid, octadecadienoic acid, octadecatrienoic acid, eicosatetraenoic acid, or any combination thereof.

8. The method of claim 4 , wherein the unsaturated fatty acid comprises eicosapentaenoic acid 20:5ω3 (EPA), docosahexaenoic acid 22:6ω3 (DHA), docosapentaenoic acid 22:5ω3 (DPA), or any mixture thereof.

9. The method of claim 4 , wherein the alcohol is glycerol.

10. The method of claim 4 , wherein the enzyme is from 0.1% to 20% by weight of the reaction.

11. The method of claim 4 , wherein after the reaction between the ester and the alcohol, the amount of ester that is transesterified is from 70 to 100%.

12. The method of claim 4 , wherein the ester comprises an ethyl ester of eicosapentaenoic acid 20:5ω3 (EPA), docosahexaenoic acid 22:6ω3 (DHA), docosapentaenoic acid 22:5ω3 (DPA), or any mixture thereof, and the alcohol comprises glycerol, wherein the ester and the alcohol are present in a molar ratio of from 2:1 to 5:1, wherein the reaction is stirred in the presence of the immobilized enzyme at a temperature of from 70° C. to 90° C. for 20 hours to 24 hours, wherein the matrix comprises a copolymer of divinylbenzene and styrene.

13. A method for esterifying a carboxylic acid, comprising reacting the acid with an alcohol in the presence of the immobilized enzyme of claim 1 , wherein the carboxylic acid comprises an unsaturated fatty acid.

14. The method of claim 13 , wherein the unsaturated fatty acid is derived from fish oil.

15. The method of claim 13 , wherein the unsaturated fatty acid is an omega-3 fatty acid.

16. The method of claim 13 , wherein the unsaturated fatty acid is linoleic acid, linolenic acid, gamma-linolenic acid, arachidonic acid, mead acid, stearidonic acid, alpha-eleostearic acid, eleostearic acid, pinolenic acid, docosadienic acid, docosatetraenoic acid, octadecadienoic acid, octadecatrienoic acid, eicosatetraenoic acid, or any combination thereof.

17. The method of claim 13 , wherein the unsaturated fatty acid comprises eicosapentaenoic acid 20:5ω3 (EPA), docosahexaenoic acid 22:6ω3 (DHA), docosapentaenoic acid 22:5ω3 (DPA), or any mixture thereof.

18. The method of claim 13 , wherein the alcohol is glycerol.

19. The method of claim 13 , wherein the enzyme is from 0.1% to 20% by weight of the reaction.

20. The method of claim 13 , wherein after the reaction between the carboxylic acid and the alcohol, the amount of carboxylic acid that is esterified is from 70 to 100%.

21. The method of claim 13 , wherein the carboxylic acid comprises eicosapentaenoic acid 20:5ω3 (EPA), docosahexaenoic acid 22:6ω3 (DHA), docosapentaenoic acid 22:5ω3 (DPA), or any mixture thereof, and the alcohol comprises glycerol, wherein the ester and the alcohol are present in a molar ratio of from 2:1 to 5:1, wherein the reaction is stirred in the presence of the immobilized enzyme at a temperature of from 60° C. to 90° C. for 2 hours to 24 hours, wherein the matrix comprises a copolymer of divinylbenzene and styrene.