Process for a direct one-pot transformation of lutein to β-cryptoxanthin via its acetate ester

Patent metadata

Field	Value
Publication number	US-9725411-B2
Application number	US-201414891499-A
Country	US
Kind code	B2
Filing date	May 16, 2014
Priority date	May 16, 2013
Publication date	Aug 8, 2017
Grant date	Aug 8, 2017

Abstract

The present invention relates to a process for converting commercially available lutein and/or lutein esters from extracts of marigold flower petals to (3R)-β-cryptoxanthin (major) and (3R,6′R)-α-cryptoxanthin (minor) in ratios ranging from 95:5 to 98:2 in a one-pot reaction at room temperature. Because the entire process can be carried out by employing safe and environmentally friendly food-grade reagents, the resulting mixture of these carotenoids is suitable for human consumption as a dietary supplement.

First claim

What is claimed is:

1. A process for the preparation of (3R)-β-cryptoxanthin acetate comprising reacting (3R,3′R,6′R)-lutein with concentrated mineral acid or a strong organic acid, a heterogeneous hydrogenation catalyst, an acylating ester, and hydrogen in one reaction to give (3R)-β-cryptoxanthin acetate.

2. The process of claim 1 , wherein the (3R,3′R,6′R)-lutein is purified by pretreatment with a dilute solution of a mineral acid in an alcohol at a temperature between about 50° C. to about 60° C. to remove anthocyanins and degradation products of chlorophylls.

3. The process of claim 1 , further comprising a solvent selected from the group consisting of acetone, tetrahydrofuran, a hydrocarbon solvent, and combinations thereof.

4. The process of claim 1 , wherein the acylating ester is selected from the group consisting of ethyl acetate, methyl acetate, isopropyl acetate, propyl acetate, and isopropenyl acetate.

5. The process of claim 3 , wherein the hydrocarbon solvent is selected from the group consisting of pentane, hexane, and heptane.

6. The process of claim 1 , wherein the concentrated mineral acid or strong organic acid is selected from the group consisting of about 50% sulfuric acid, hydrochloric acid, phosphoric acid, trifluoroacetic acid, and benzenesulfonic acid.

7. The process according to claim 1 , wherein the heterogeneous hydrogenation catalyst is selected from the group consisting of platinum (Pt) supported on alumina (5%), Pt supported on activated carbon (5%), Pt supported on activated carbon (10%), palladium (Pd) supported on activated carbon (5%), Pd supported on activated carbon (10%), Pd supported on alumina (5%), Pd supported on alumina (10%), Pd supported on calcium carbonate (5%), Pd 3% on polyethyleneimine/SiO 2 , rhodium (Rh) supported on alumina (5%), ruthenium supported on carbon, and ruthenium supported on alumina.

8. The process according to claim 1 , wherein the reacting is carried out at a temperature between about 23° C. to about 45° C.

9. The process of claim 1 , wherein the (3R,3′R,6′R)-lutein is present in a composition comprising 4-5% (3R,3′R)-zeaxanthin.

10. The process of claim 1 , wherein the (3R,3′R,6′R)-lutein may be present as lutein fatty acid esters in a composition comprising 4-5% (3R,3′R)-zeaxanthin fatty acid esters.

11. The process of claim 10 , wherein the lutein fatty acid esters are selected from the group consisting of lutein dimyristate, lutein dipalmitate, and combinations thereof.

12. The process of claim 10 , wherein the source of the lutein fatty acid esters is extracts of marigold flowers or marigold petal flowers.

13. The process of claim 10 , wherein the lutein fatty acid esters are purified by pretreatment with a dilute solution of a mineral acid in an alcohol at a temperature between about 50° C. and about 60° C. to remove the anthocyanins and degradation products of chlorophylls.

14. The process of claim 13 , wherein the mineral acid is selected from the group consisting of hydrochloric acid, sulfuric acid, and phosphoric acid.

Assignees

• Univ Maryland

Inventors

• Khachik Frederick

Classifications

• C07C403/24 Primary

  having side-chains substituted by six-membered non-aromatic rings, e.g. beta-carotene · CPC title

• C07C2601/16

  the ring being unsaturated · CPC title

• C07C2101/16

  Chemistry & Metallurgy · mapped topic