Sharma , K and Bari, S S and Singh , H P (2009) Biotransformation of tea catechins into theaflavins with immobilized polyphenol oxidase. Journal of Molecular Catalysis B: Enzymatic, 56 (4). pp. 253-258.

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Abstract

Theaflavins, an active antioxidant, a natural pigment and pharmacologically active molecule obtained from black tea were bioprocessed on an immobilized tea polyphenol oxidase (PPO) system by the conversion of tea catechins extracted from green tea leaves with an overall conversion efficiency of 85% about 14-fold increase over maximum achievable in normal black teas. The immobilized enzyme (IE) system consists of activated cellulose matrix on to which the freshly extracted tea leaf polyphenol oxidase was covalently linked. Cellulose as a matrix of choice was considered primarily for its non-toxic nature, natural origin, low cost and easy availability. The kinetic parameters of the IE system were; protein loading capacity 11.8 mg/g; pH optimum 5.9; temperature optimum 37.5 °C; Km 4.76 ± 0.08 mM; Vmax 20 ± 1.80 nmol/min; enzyme activity retention (83.58%) and number of batches per turnover without loss of activity was 14. The product from IE system was identified by HPLC and ESI-QTOF-MS spectrometry.

Item Type:	Article
Uncontrolled Keywords:	Biotransformation; Bioprocessing; Theaflavins; Catechins; Immobilization; Immobilized enzyme; Matrix; Substrate; Polyphenol oxidase
Subjects:	Nutraceuticals
Divisions:	UNSPECIFIED
Depositing User:	Dr. Aparna Maitra Pati
Date Deposited:	29 Dec 2011 14:50
Last Modified:	15 Mar 2013 08:26
URI:	http://ihbt.csircentral.net/id/eprint/672

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