METABOLISM OF 8-PRENYLNARINGENIN, A POTENT PHYTOESTROGEN FROM HOPS (HUMULUS LUPULUS), BY HUMAN LIVER MICROSOMES

• DOI: 10.1124/dmd.32.2.272
• Publication Date: 2004-01-26T20:25:10Z
• Authors: Dejan Nikolic; Yongmei Li; Lucas R. Chadwick; Simonida Grubjesic; Pia Schwab; Peter Metz; Richard B. van Br...
• Keywords: Flavanone; Hydroxylation; Humulus lupulus; Biotransformation

The female flowers of hops are used throughout the world as a flavoring agent for beer. Recently, there has been increasing interest in potential estrogenic properties hop extracts. Among possible compounds hops, 8-prenylnaringenin is perhaps most significant due to its high vitro potency exceeding that other known phytoestrogens. Since data regarding pharmacokinetic this compound lacking, we investigated metabolism by human liver microsomes. A total 12 metabolites were identified, and biotransformation occurred on prenyl group flavanone skeleton. major site oxidation was terminal methyl groups, two isomers, the<i>trans</i>isomer more abundant. double bond also oxidized an epoxide opened intramolecular reaction with neighboring hydroxyl group. On skeleton, at 3′position B ring. Other included carbon-3 well desaturation C ring produce 8-prenylapigenin. An unusual hydroxy quinone product formed by<i>ipso</i>hydroxylation detected. This probably intermediate cleavage product, 8-prenylchromone.