Structure and Isolation of Xanthine Oxidase Inhibitor from Oolong Tea

우롱차로부터 Xanthine Oxidase 저해물질 분리 및 구조

  • Published : 1992.12.01

Abstract

Xanthine oxidase involved in pruine metabolism oxidizes hypoxanthine to xanthine and xanthine to uric acid. The derangement of pruine metabolism results in gout that associates painful deposit of monosodium urate in the cartilage of joints. In the continuous study for natural compound, six flavan-3-ols have been isolated from the leaves of Oolong tea. The structures of procyanidin B-1, B-3, procyanidin B-3-3-O-rhamnose, procyanidin B-1-3-O-gallate, (-)-epicatechin, (-)-epicatechin-3-O-gallate were established by NMR and their inhibitory effect on xanthine oxidase activity was investigated. Flavan-3-ols containing the gallate had a high inhibitory capacity. Procyanidin B-1-3-O-gallate showed complete inhibition at $50\;{\mu}M$ and inhibited on the xanthine oxidase competitively.

Keywords

xanthine oxidase inhibitor;flavan-3-ol;Oolong tea