Method and system for production of zein and/or xanthophylls using chromatography

• US 20090215990A1
• Filed: 05/08/2007
• Published: 08/27/2009
• Est. Priority Date: 05/08/2006
• Status: Active Grant

• Current Assignee: Board of Trustees of The University of Illinois
• Original Assignee: Board of Trustees of The University of Illinois
• Inventors: Shane, Philip L., Kale, Aniket V., Zhu, Fangyi, Cheryan, Munir
• Granted Patent: US 8,236,929 B2
• Time in Patent Office: Days
• US Class Current: 530/373
• CPC Class Codes: C07K 14/415 from plants
• CPC Class Codes: C09B 61/00 Dyes of natural origin prepared from natural sources , e.g. vegetable sources
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel

Abstract

Methods and systems for obtaining zein and/or xanthophylls in highly pure form. Zein is first extracted from corn using aqueous ethanol. Suspended corn solids are separated, and the resulting extract is purified in a single size-exclusion chromatography step to separate impurities and produce substantially purified zein. The chromatography step may simultaneously produce substantially purified xanthophylls.

Claims

1. A process for producing zein and/or xanthophylls from corn, the process comprising:

extracting soluble compounds from a corn-based material with a solvent to provide a corn-solvent mixture, the soluble compounds comprising at least zein and xanthophylls;

first separation of the com-solvent mixture into two streams, of which one stream is an extract containing substantially the zein, impurities, xanthophylls and solvent, wherein the impurities comprise substantially all components in the extract other than solvent, zein and xanthophylls, and another stream containing the remaining corn solids and solvent, said first separation comprising at least one of centrifugation, filtration, and membrane microfiltration;

second separation to separate the zein from non-zein components in the extract comprising at least the impurities and/or xanthophylls, said second separation comprising chromatography based on a size-exclusion mechanism.

2. The process of claim 1, further comprising:

concentrating the separated zein by removing the solvent.

3. The process of claim 2, wherein said concentrating the separate zein comprises nanofiltration.

4. The process of claim 2, wherein said concentrating the separate zein comprises using reverse osmosis.

5. The process of claim 2, wherein said concentrating the separated zein comprises using adsorption chromatography.

6. The process of claim 5, wherein a mobile phase used for elution in the adsorption chromatography comprises ethyl acetate.

7. The process of claim 1, further comprising:

before said second separation, concentrating the extract to provide a higher level of solids in a concentrated extract, wherein said concentrating comprises membrane filtration;

wherein said second separation separates said concentrated extract.

8. The process of claim 7, wherein said concentrating the extract further comprises dehydration.

9. The process of claim 1, further comprising:

before said second separation, concentrating the extract to provide a higher level of solids in a concentrated extract, wherein said concentrating comprises membrane filtration, wherein said second separation separates said concentrated extract;

after said second separation, concentrating the separated zein by removing the solvent.

10. The process of claim 1, wherein the solvent is an alcohol.

11. The process of claim 10, wherein the alcohol is 60-100% aqueous ethanol.

12. The process of claim 1, wherein said extraction comprises at least one of batch and continuous extraction.

13. The process of claim 1, wherein said first separation comprises centrifugation.

14. The process of claim 1, wherein said first separation comprises filtration.

15. The process of claim 1, wherein said first separation comprises membrane microfiltration.

16. The process of claim 1, wherein chromatographic media used in said second separation has a molecular weight exclusion limit of 10,000 or less.

17. The process of claim 16 wherein the chromatographic media has a molecular weight exclusion limit of 5000 or less.

18. The process of claim 1, wherein a mobile phase used in said second separation to elute the fractions comprises aqueous alcohol.

19. The process of claim 1, further comprising:

fractionating the non-zein components to result in a fraction that is enriched in xanthophylls and another fraction that is substantially devoid of xanthophyll.

20. The process of claim 1, wherein the com-based material comprises at least one of corn gluten meal, distillers dried grains with or without solubles, and com-based materials that have been partially or substantially de-oiled.

21. The process of claim 1, wherein the separated zein has a purity of at least 90%.

22. A process for producing zein and xanthophyll from corn, the process comprising:

extraction of soluble compounds from a com-based material with an aqueous ethanol solvent to provide a corn-solvent mixture, the soluble compounds comprising at least zein and/or xanthophylls;

first separation of the corn-solvent mixture into two streams, of which one stream is an extract containing substantially the zein, xanthophylls, impurities, and solvent, and another stream containing the remaining corn solids and solvent, said first separation comprising at least one of centrifugation, filtration, and membrane microfiltration, wherein the impurities comprise substantially all components in the extract other than solvent, zein, and xanthophylls;

second separation of a zein fraction and a xanthophylls fraction from the extract comprising the impurities in the extract, said second separation comprising chromatography based on a size-exclusion mechanism,;

concentrating the separated zein fraction eluting from the column by removing the solvent;

concentrating the separated xanthophyll fraction eluting from the column by removing the solvent.

23. The process of claim 22, wherein said second separation uses aqueous ethanol for a mobile phase.

24. The process of claim 23, wherein the aqueous ethanol in both said extraction and said second separation have substantially the same ethanol concentration.

25. The process of claim 23, wherein the aqueous ethanol in both said extraction and said second separation have an ethanol concentration of about 70-95%.

26. The process of claim 23, further comprising:

recycling ethanol from at least one of said extraction, said first separation, said second separation, said concentrating the separated zein fraction, and said concentrating the separated xanthophyll fraction.

27. A method for producing xanthophylls from corn, the method comprising:

extracting soluble compounds from a corn-based material with an aqueous ethanol solvent to provide a corn-solvent mixture, the soluble compounds comprising at least the xanthophylls;

first separating the corn-solvent mixture into two streams, of which one stream is an extract containing substantially the zein, xanthophylls, impurities, and solvent, and another stream containing the remaining corn solids and solvent, said first separating comprising at least one of centrifugation, filtration, and membrane microfiltration, wherein the impurities comprise substantially all components in the extract other than zein and xanthophylls;

second separating at least a xanthophylls fraction from a fraction containing non-xanthophyll components including impurities, said second separating comprising chromatography based on a size-exclusion mechanism;

concentrating the separated xanthophyll fraction eluting from the column by removing the solvent.

28. A system for producing zein and xanthophyll from corn, the system comprising:

an extractor for extracting soluble compounds from a corn-based material with an aqueous ethanol solvent to provide a corn-solvent mixture, the soluble compounds comprising at least xanthophylls;

a clarifier for first separating the corn-solvent mixture into two streams, of which one stream is an extract containing substantially the zein, xanthophylls, impurities, and solvent, and another stream containing the remaining corn solids and solvent, said clarifier comprising at least one of a centrifuge, a filter, and a membrane microfilter wherein the impurities comprise substantially all components in the extract other than zein and xanthophylls;

at least one chromatographic column based on a size-exclusion mechanism for second separating a zein fraction and a xanthophylls fraction from a fraction of the extract comprising the impurities in the extract;

a concentrator comprising at least one of a membrane concentration device and an adsorption chromatography device for concentrating the separated zein fraction eluting from the column by removing the solvent;

a concentrator comprising at least one of a membrane concentration device and an adsorption chromatography device for concentrating the separated xanthophyll fraction eluting from the column by removing the solvent.

29. The system of claim 28, further comprising:

a membrane concentration device disposed between said clarifier and said at least one chromatographic column for concentrating zein in the extract.

30. The system of claim 29, wherein at least one of said extractor, clarifier, chromatographic column, concentrator for concentrating the separated zein fraction, and concentrator for concentrating the separated xanthophyll fraction further comprises an output line for delivering ethanol for recycling.