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Towards catalyst compartimentation in combined chemo- and biocatalytic processes: Immobilization of alcohol dehydrogenases for the diastereoselective reduction of a β-hydroxy ketone obtained from an organocatalytic aldol reaction

Paper ID Volume ID Publish Year Pages File Format Full-Text
23482 43441 2013 6 PDF Available
Title
Towards catalyst compartimentation in combined chemo- and biocatalytic processes: Immobilization of alcohol dehydrogenases for the diastereoselective reduction of a β-hydroxy ketone obtained from an organocatalytic aldol reaction
Abstract

•ADHs from Lactobacillus kefir and Rhodococcus sp., respectively, were immobilized with their cofactors on a superabsorber based on a literature-known method.•Applying the immobilized ADH from L. kefir in the reduction of acetophenone as a model substrate led to high conversion (>95%).•Immobilized ADHs are suitable catalysts for the diastereoselective reduction of an organocatalytically prepared enantiomerically enriched aldol adduct.•At a lower catalyst and cofactor amount being still sufficient for biotransformations with “free” enzymes the immobilized ADH only showed high conversion and >99% ee for the first reaction cycle.

The alcohol dehydrogenases (ADHs) from Lactobacillus kefir and Rhodococcus sp., which earlier turned out to be suitable for a chemoenzymatic one-pot synthesis with organocatalysts, were immobilized with their cofactors on a commercially available superabsorber based on a literature known protocol. The use of the immobilized ADH from L. kefir in the reduction of acetophenone as a model substrate led to high conversion (>95%) in the first reaction cycle, followed by a slight decrease of conversion in the second reaction cycle. A comparable result was obtained when no cofactor was added although a water rich reaction media was used. The immobilized ADHs also turned out to be suitable catalysts for the diastereoselective reduction of an organocatalytically prepared enantiomerically enriched aldol adduct, leading to high conversion, diastereomeric ratio and enantioselectivity for the resulting 1,3-diols. However, at a lower catalyst and cofactor amount being still sufficient for biotransformations with “free” enzymes the immobilized ADH only showed high conversion and >99% ee for the first reaction cycle whereas a strong decrease of conversion was observed already in the second reaction cycle, thus indicating a significant leaching effect of catalyst and/or cofactor.

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Keywords
ADH, alcohol dehydrogenase; NADH, nicotinamide adenine dinucleotide reduced form; NAD+, nicotinamide adenine dinucleotide oxidized form; NADPH, nicotinamide adenine dinucleotide phosphate reduced form; NADP+, nicotinamide adenine dinucleotide phosphate ox
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Towards catalyst compartimentation in combined chemo- and biocatalytic processes: Immobilization of alcohol dehydrogenases for the diastereoselective reduction of a β-hydroxy ketone obtained from an organocatalytic aldol reaction
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Publisher
Database: Elsevier - ScienceDirect
Journal: Journal of Biotechnology - Volume 168, Issue 3, November 2013, Pages 271–276
Authors
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Subjects
Physical Sciences and Engineering Chemical Engineering Bioengineering
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
Online Support
Any Questions? feel free to contact us