Highly regioselective enzymatic synthesis of lutein-3-monoesters

Abstract

Lutein, a xanthophyll carotenoid abundant in marigold flowers (Tagetes spp.), is found in the form of ester derivatives of fatty acids. Herein we present an enzymatic approach for the regioselective synthesis of 3-O-acyl monoester lutein derivatives (β-ionone selectivity, up to 17:1), using a lipase (Novozyme 435, immobilized CALB), and vinyl carboxylates (vinyl propionate and stearate) as acyl donors. The regioselectivity arises from the highly stereoselective feature of CALB. This methodology addresses the long-standing problem of regioselective monoesterification of lutein, potentially enabling novel, semisynthetic routes to other monoester xanthophyll carotenoids.