Asymmetric reduction of alkyl-3-oxobutanoates mediated by Candida parapsilosis ATCC 7330 resulted in optically pure alkyl-3-hydroxybutanoates in good yields (up to 72 %) and excellent enantiomeric excess (up to >99 %). A detailed and systematic optimisation study was necessary and was carried out to avoid the undesired transesterification reaction during the course of asymmetric reduction. Under optimised conditions, the (S)-alkyl hydroxyesters were produced predominantly except for the methyl ester which formed the (R)-enantiomer. To the best of our knowledge, the biocatalytic asymmetric reduction of isoamyl-3-oxobutanoate to (S)-isoamyl-3-hydroxybutanoate is reported here for the first time. © 2013 Springer Science+Business Media New York.

Anju Chadha

Department Of Biotechnology

ALKYL-3-OXOBUTANOATES

Asymmetric reduction

Biocatalytic reaction

CANDIDA PARAPSILOSIS

Enantiomeric excess

Methyl esters

OPTIMISED CONDITIONS

Transesterification reaction

Enantiomers

Optimization

Transesterification

Candida

ester derivative

ISOAMYL 3 HYDROXYBUTANOATE

ISOAMYL 3 OXOBUTANOATE

solvent

unclassified drug

analytic method

article

Biocatalysis

Biocatalyst

chemical reaction

chirality

enantiomer

gas chromatography

infrared spectroscopy

MASS SPECTROMETER

microwave radiation

nonhuman

Nuclear magnetic resonance spectroscopy

reaction analysis

reduction

Butyrates

Hydroxybutyrates

Oxidation-Reduction

Solvents

Stereoisomerism

Substrate Specificity

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Applied Biochemistry and Biotechnology

This review highlights the importance of the biocatalyst, Candida parapsilosis for oxidation and reduction reactions of organic compounds and establishes its versatility to generate a variety of chiral synthons. Appropriately designed reactions using C. parapsilosis effect efficient catalysis of organic transformations such as deracemization, enantioselective reduction of prochiral ketones, imines, and kinetic resolution of racemic alcohols via selective oxidation. This review includes the details of these biotransformations, catalyzed by whole cells (wild type and recombinant strains), purified enzymes (oxidoreductases) and immobilized whole cells of C. parapsilosis. The review presents a bioorganic perspective as it discusses the chemo, regio and stereoselectivity of the biocatalyst along with the structure of the substrates and optical purity of the products. Fermentation scale biocatalysis using whole cells of C. parapsilosis for several biotransformations to synthesize important chiral synthons/industrial chemicals is included. A comparison of C. parapsilosis with other whole cell biocatalysts for biocatalytic deracemization and asymmetric reduction of carbonyl and imine groups in the synthesis of a variety of enantiopure products is presented which will provide a basis for the choice of a biocatalyst for a desired organic transformation. Thus, a wholesome perspective on the present status of C. parapsilosis mediated organic transformations and design of new reactions which can be considered for large scale operations is provided. Taken together, C. parapsilosis can now be considered a ‘reagent’ for the organic transformations discussed here. © 2016 Elsevier Inc.

Bioorganic Chemistry

Candida parapsilosis: A versatile biocatalyst for organic oxidation-reduction reactions

Confocal microscopic studies with the resting cells of yeast, Candida parapsilosis ATCC 7330, a reportedly versatile biocatalyst for redox enzyme mediated preparation of optically pure secondary alcohols in high optical purities [enantiomeric excess (ee) up to >99%] and yields, revealed that the yeast cells had large vacuoles under the experimental conditions studied where the redox reaction takes place. A novel fluorescence method was developed using 1-(6-methoxynaphthalen-2-yl)ethanol to track the site of biotransformation within the cells. This alcohol, itself non-fluorescent, gets oxidized to produce a fluorescent ketone, 1-(6-methoxynaphthalen-2-yl)ethanone. Kinetic studies showed that the reaction occurs spontaneously and the products get released out of the cells in less time [5 mins]. The biotransformation was validated using HPLC.

Fulltext

Scientific Reports

Direct observation of redox reactions in Candida parapsilosis ATCC 7330 by Confocal microscopic studies

Enantiomerically pure β- and γ-nitro alcohols were prepared from their respective nitro ketones by asymmetric reduction mediated by the biocatalyst, Candida parapsilosis ATCC 7330 under optimized reaction conditions (ee up to >99%; yields up to 76%). This biocatalyst exhibits high chemoselectivity and reduces the keto group in preference to nitro group along with good enantioselectivity to produce enantiomerically enriched nitro alkanols. The asymmetric reduction of aliphatic nitro ketones was carried out in water with ethanol as cosolvent and glucose as cosubstrate using the whole cells of Candida parapsilosis ATCC 7330 in much lesser time (4 h). For the first time, the biocatalytic asymmetric reduction of the following ketones is reported here: 1-nitro-butan-2-one, 1-nitro-pentan-2-one, 3-methyl-1-nitro-butan-2-one and 1-cyclohexyl-2-nitroethanone to produce (R)-alcohols [ee up to 79%, yield up to 74%] and 1-nitro-hexan-2-one and 1-nitro-heptan-2-one to produce (S)-alcohols [ee up to 81%, yield up to 76%]. © The Royal Society of Chemistry.

RSC Advances

Enantio- &amp; chemo-selective preparation of enantiomerically enriched aliphatic nitro alcohols using Candida parapsilosis ATCC 7330

Optically pure (S)-ethyl 3-hydroxy 4,4,4-trifluorobutanoate was prepared using the biocatalyst Candida parapsilosis ATCC 7330 by deracemisation of the racemic alcohol ester in high optical purity (96%) and yield (65%) and by asymmetric reduction from its prochiral ketone (ee up to 84% and yield 60%) under different reaction conditions. This study highlights the possibility of using the same biocatalyst to produce (S)-ethyl 3-hydroxy 4,4,4-trifluorobutanoate using different strategies. ©2014 Elsevier B.V. All rights reserved.

Journal of Fluorine Chemistry

Preparation of enantiomerically enriched (S)-ethyl 3-hydroxy 4,4,4-trifluorobutanoate using whole cells of Candida parapsilosis ATCC 7330

A green, simple and high yielding [up to 86% yield] procedure is developed for the oxidation of aromatic (activated) primary alcohols to aldehydes using whole cells of Candida parapsilosis ATCC 7330. The biotransformation is carried out under mild conditions at 25 °C, in hexane: water (48 : 2) (v/v). © The Royal Society of Chemistry.

Candida parapsilosis ATCC 7330 mediated oxidation of aromatic (activated) primary alcohols to aldehydes

Candida parapsilosis ATCC 7330 when grown in a medium containing glycerol reduced ethyl-4-chloro-3-oxobutanoate to (R)-ethyl-4-chloro-3-hydroxybutanote (ee >99%, yield: 94%) while glucose and sucrose grown cells yielded (S)-ethyl-4-chloro-3-hydroxybutanote (ee >99%, yield: 96%). The activity of ethyl-4-chloro-3-oxobutanoate reductase was higher in glucose-grown cells (160 U/g protein) when compared to sucrose (158 U/g protein) and glycerol (22 U/g protein). Both the enantiomers of ethyl-4-chloro-3-hydroxybutanoate (ee >99%) can thus be obtained using Candida parapsilosis ATCC 7330 by altering the carbon source in the growth medium. © 2011 Elsevier Ltd. All rights reserved.

Tetrahedron Asymmetry

Synthesis of both enantiomers of ethyl-4-chloro-3-hydroxbutanoate from a prochiral ketone using Candida parapsilosis ATCC 7330

Racemic alkyl-2-hydroxy-4-arylbut-3-ynoates were deracemized to the (S)-alkyl-2-hydroxy-4-arylbut-3-ynoates in excellent enantiomeric excesses (up to &gt;99%) and good isolated yields (up to 81%) with the biocatalyst Candida parapsilosis ATCC 7330. The absolute configuration of the resulting enantiomer was assigned by 1H NMR using Mosher's method. © 2010 Elsevier Ltd. All rights reserved.

Biocatalytic deracemization of alkyl-2-hydroxy-4-arylbut-3-ynoates using whole cells of Candida parapsilosis ATCC 7330

Biocatalytic deracemisation of racemic allylic alcohols by whole cells of Candida parapsilosis ATCC 7330 resulted in the formation of the (R)-enantiomers in high enantiomeric excesses (up to >99%) and isolated yields (up to 79%). © 2008 Elsevier Ltd. All rights reserved.

Enantiomerically pure allylic alcohols: preparation by Candida parapsilosis ATCC 7330 mediated deracemisation

A highly enantioselective one pot, novel biocatalytic method for the asymmetric reduction of aryl imines is reported. Treatment of aryl imines with Candida parapsilosis ATCC 7330 in aqueous medium produces the enantiomerically pure (R)-secondary amines in moderate to good yields (55-80%) with excellent enantiomeric excesses (95->99%). © 2007 Elsevier Ltd. All rights reserved.

Asymmetric reduction of aryl imines using Candida parapsilosis ATCC 7330

Enantioselective bioreduction of alkyl 2-oxo-4-arylbutanoates and 2-oxo-4-arylbut-3-enoates mediated by Candida parapsilosis ATCC 7330 resulted in the formation of the corresponding (S)-2-hydroxy compounds in high enantiomeric excesses (93-99%) and good isolated yields (58-71%). The absolute configuration of enantiomerically pure ethyl 2-hydroxy-4-(p-methylphenyl)but-3-enoate obtained by the reduction of the corresponding keto ester was assigned by 1H NMR using Mosher's method. © 2004 Elsevier Ltd. All rights reserved.

Asymmetric reduction of alkyl 2-oxo-4-arylbutanoates and -but-3-enoates by Candida parapsilosis ATCC 7330: Assignment of the absolute configuration of ethyl 2-hydroxy-4-(p-methylphenyl)but-3-enoate by 1H NMR

Asymmetric reduction of alkyl-3-oxobutanoates by Candida parapsilosis ATCC 7330: Insights into solvent and substrate optimisation of the biocatalytic reaction

Journal	Applied Biochemistry and Biotechnology
ISSN	02732289
Open Access	No