STUDIES ON ANTIBACTERIAL CONSTITUENTS OF GERBERA ANANDRIA (L.) SCH.-BIP.: THE METABOLITE OF GERBERINSIDE AND RELATED COMPOUNDS BY HUMAN INTESTINAL BACTERIA IN VITRO

The metabolites of three coumarin glucosides (Ⅴ, Ⅷ and Ⅸ) by human intestinal bacteria in vitro is described. Two major metabolites (Ⅰ and Ⅱ) were isolated and identified, Ⅴ showed no antibacterial activities in vitro, but was active in vivo. The metabolites (Ⅰ and Ⅱ) of Ⅴ incubated with human intestinal bacteria also showed antibacterial activities. The results showed that the antibacterial activities of compounds Ⅴ, Ⅷ and Ⅸ are connected with the production of compounds Ⅰ and Ⅱ. A new metabolic pathway of 4-hydroxycoumarin has been found.