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Partial and enantioselective hydrolysis of diethyl phenylmalonate by immobilized preparations of lipase from Thermomyces lanuginose

Paper ID Volume ID Publish Year Pages File Format Full-Text
18175 42713 2007 6 PDF Available
Title
Partial and enantioselective hydrolysis of diethyl phenylmalonate by immobilized preparations of lipase from Thermomyces lanuginose
Abstract

Prochiral dimethyl or diethyl phenylmalonate were partially hydrolysed to the corresponding chiral monoesters by different immobilized preparations of lipase from Thermomyces lanuginosa. This enzyme does not hydrolyse the monoesters and hence its hydrolysis was carried out without production of the final achiral di-carboxylic acid, quantitatively yielding the chiral monoester. Asymmetry factor with preference towards to production of the (+)-isomer could be increased from 1.5 up to 10 depending on the immobilized preparation, the type of acyl donor and the presence of co-solvents. Thus, different immobilized preparations of the same lipase, when acting at different experiment conditions, may exhibit a very different activity and enantioselectivity. Furthermore the presence of small concentrations of detergents (from 0.01 to 1%) in the reaction media exerts dramatic effects on the activity and enantioselectivity of TLL immobilized on conventional supports (e.g., covalently immobilized on CNBr-activated agarose). The presence of Triton X-100 has strong inhibitory effects and hardly modifies the enantioselectivity of the derivatives. However, a cationic detergent (CTAB), promotes very significant improvements of activity (by a 40-fold factor) and enantioselectivity (from 3.5 to 20). Under these conditions a highly enantioselective asymmetric hydrolysis, obtaining the (+)-1-(ethoxy-carbonyl)-phenylmalonic acid with an e.e. over 90% can be obtained.

Keywords
Partial hydrolysis; Asymmetric reactions; Modulation of lipase; Interfacially activated lipases
First Page Preview
Partial and enantioselective hydrolysis of diethyl phenylmalonate by immobilized preparations of lipase from Thermomyces lanuginose
Publisher
Database: Elsevier - ScienceDirect
Journal: Enzyme and Microbial Technology - Volume 40, Issue 5, 3 April 2007, Pages 1280–1285
Authors
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Subjects
Physical Sciences and Engineering Chemical Engineering Bioengineering