Evaluation of the Anti-oxidative Effect (in vitro) of Tea Polyphenols

Abstract

Forty-three polyphenols from tea leaves were evaluated for their anti-oxidative effect against lipid peroxidation by the ferric thiocyanate method in vitro. Among these, 1,4,6-tri-O-galloyl-beta-D-glucose (hydrolyzable tannin) showed the highest anti-oxidative activity against lipid peroxidation, even stronger than that of 3-tert.-butyl-4-hydroxyanisole (BHA). The assay demonstrates that tea polyphenols, except for desgalloylated dimeric proanthocyanidins that possess a catechin structure in the upper unit and desgalloylated flavan-3-ols, and excepting theaflavin 3,3'-di-O-gallate, had more anti-oxidative activity than that of alpha-tocopherol. The chemical structure-activity relationship shows that the anti-oxidative action advanced with the condensation of two molecules of flavan-3-ols as well as with 3-O-acylation in the flavan skeleton such as that by galloyl, (3'-O-methyl)-galloyl, and p-coumaroyl groups.

Antioxidant Potential of Green and Black Teas of Selected South India Cultivars

“…3 and 4). Conversely, theaflavins, which are formed from catechins during fermentation, showed lower antioxidant activities compared with catechins 6 . In black tea, since the concentration of catechins is low, the major contribution to antioxidant activity came from theaflavins.…”

Binding Energy of Tea Catechin/Caffeine Complexes in Water Evaluated by Titration Experiments with1H-NMR

“…They have recently been discovered to have various physiologically modulating effects such as anti-carcinogenic, [1][2][3][4][5][6][7] anti-metastatic, [8][9][10][11] anti-oxidative, [12][13][14][15] antihypertensive, 16) anti-hypercholesterolemic, [17][18][19] antibacterial, 20) anti-dental caries, [21][22][23] and intestinal flora amelioration activities. 24) Caffeine (1, Fig.…”

Changes in Epigallocatechin-3-0- (3-0-methyl) Gallate and Strictinin Contents of Tea (Camellia sinensis L.) Cultivar 'Benifuki' in Various Degrees of Maturity and Leaf Order

“…anti-carcinogenetic (Kuroda & Hara, 1999;Lin et ul., 1999;Suganuma et ul., 1999, 200_3;Ahmad et a!., 2000;Cao & Cao, 1999;Lambert & Yan_~, 2003), anti-metastatic (Sazuka et a/., 1997; Maeda-Yamamoto et a/., 1999; Isemura et a!., 199_3; Sazuka et a/., 1995), anti-oxidative (Bors & Saran, 1987;Hashimoto et a!., 2003;Okuda et al, 1983;Kimura et a!., 2002), anti-hypertensive (Yokozawa et a!., 1994), anti-hypercholesterolemic (Murase et al, 2002;Chlsaka et a/., 1988; Matsumoto et a!., 1998), anti-dental caries (Sakanaka et a/., 1992;Hattori et a!., 1990), antl-bacterial (Fukai et al, 1991), and intestinal fiora amelioration activity (Okubo et a/., 1992).…”