Collect. Czech. Chem. Commun. 2009, 74, 1467-1475
Published online 2009-12-14 10:29:26

Estimation of antioxidative properties of tea leaves by abrasive stripping electrochemistry using paraffin-impregnated graphite electrode

Šebojka Komorsky-Lovrića,* and Ivana Novakb

a Ruđer Bošković Institute, Bijenička 54, HR-10000 Zagreb, Croatia
b Faculty of Food Technology, J. J. Strossmayer University, F. Kuhača 18, HR-31000 Osijek, Croatia


Electrooxidation potentials of powdered green and black teas were determined by abrasive stripping voltammetry. A circular surface of paraffin-impregnated graphite rod was contaminated with tea microparticles and used as a chemically prepared working electrode in square-wave voltammetric experiments. The responses are ascribed to electrooxidation of flavanols in teas. Low oxidation potentials of some green teas were observed. An advantage of the proposed method is that no extraction of electroactive components is necessary.

Keywords: Tea; (–)-Epigallocatechin gallate; (–)-Epigallocatechin; (–)-Epicatechin gallate; PIGE; Square-wave voltammetry; Electrooxidation; Antioxidants; Abrasive stripping voltammetry; Green tea.

References: 25 live references.