In vitro glucuronidation of xanthohumol, a flavonoid in hop and beer, by rat and human liver microsomes

Xanthohumol (XN) is the major prenylated flavonoid of hop plants and has be en detected in beer. Previous studies suggest a variety of potential cancer chemopreventive effects for XN, but there is no information on its metabol ism. The aim of this study was to investigate in vitro glucuronidation of X N by rat and human liver microsomes. Using high-performance liquid chromato graphy, two major glucuronides of XIV were found with either rat or human l iver microsomes, Release of the aglycone by enzymatic hydrolysis with beta -glucuronidase followed by liquid chromatography/mass spectrometry and nucl ear magnetic resonance analysis revealed that these were C-4' and C-4 monog lucuronides of XN. (C) 2001 Federation of European Biochemical Societies. P ublished by Elsevier Science B.V. All rights reserved.