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.

Anju Chadha

Department Of Biotechnology

Thakkellapati Sivakumari

Aldehydes

Aromatic compounds

yeast

CANDIDA PARAPSILOSIS

PRIMARY ALCOHOLS

Whole cell

Candida

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

RSC Advances

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

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

Optically pure aliphatic β-hydroxy esters were prepared from their racemates by deracemisation using the biocatalyst Candida parapsilosis ATCC 7330. High optical purity (up to >99 %) and good yields (up to 71 %) of the product secondary alcohols were obtained. This study highlights the importance of optimization of reaction conditions using ethyl-3-hydroxybutanoate as the model substrate to improve the enantioselectivity (enantiomeric excess from 9 to 98 %). The present study emphasises the broad substrate scope of the biocatalyst towards deracemisation. This is the first report of Candida parapsilosis ATCC 7330-mediated deracemisation of various alkyl-3-hydroxybutanoates to produce either the (R)-enantiomers (methyl, ethyl, propyl, butyl, t-butyl, allyl-3-hydroxybutanoates) or (S)-enantiomers (pentyl, iso-amyl and iso-propyl-3-hydroxybutanoates). © 2014, Society for Industrial Microbiology and Biotechnology.

Journal of Industrial Microbiology and Biotechnology

Biocatalytic deracemisation of aliphatic β-hydroxy esters: Improving the enantioselectivity by optimisation of reaction parameters

Optically pure allylic alcohols and 4-phenylbutan-2-ols were prepared by oxidative kinetic resolution using whole cells of Candida parapsilosis ATCC 7330. Only the 'S' enantiomer is selectively oxidized to the corresponding keto compound (yield, 37-46%) leaving the 'R' alcohol (yield, 37-52% and ee 46 to >99%). The biocatalytic method is carried out under mild conditions at 20°C, pH 6.5 in phosphate buffer. © 2014 The Royal Society of Chemistry.

Enantioselective oxidation of secondary alcohols by Candida parapsilosis ATCC 7330

Selectivity between primary and secondary alcohols was observed in oxidation using whole cells of Candida parapsilosis ATCC 7330, where the secondary alcohol was preferentially oxidized. In racemic sec alcohols, the 'R' enantiomer was selectively oxidized to the corresponding keto alcohol (yield = 18-54%) leaving the 'S' diol (yield = 31-69% and enantiomeric excess from 14% to >99%). A biphasic system consisting of isooctane-water (48 : 2 v/v) was used as a medium for biotransformation at 25 °C. This is the first report of the regio- and enantio-selective oxidation of diols using C. parapsilosis ATCC 7330. © The Royal Society of Chemistry 2014.

Regio- and enantio-selective oxidation of diols by Candida parapsilosis ATCC 7330

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.

Applied Biochemistry and Biotechnology

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

Journal	Data powered by TypesetRSC Advances
Publisher	Data powered by TypesetRoyal Society of Chemistry
ISSN	20462069
Open Access	No