The metabolism of zingerone, a pungent principle of ginger

Abstract

1. The metabolism of 4-(4-hydroxy-3-methoxyphenyl)butan-2-one (zingerone), a pungent principle of ginger, has been investigated in rats. 2. Oral or intraperitoneal dosage (100mg/kg) of zingerone resulted in the urinary excretion of most metabolites within 24 h, mainly as glucuronide and/or sulphate conjugates. While zingerone itself accounted for roughly 50-55% of the dose, reduction to the corresponding carbinol (11-13%) also occurred. Side chain oxidation took place at all three available sites and oxidation at the 3-position, giving rise to C6-C2 metabolites, predominated. About 95-97% of the dose was accounted for. 3. Appreciable (40% in 12 h) biliary excretion occurred. Biliary studies and studies in vitro using caecal micro-organisms indicated that several O-demethylated metabolites found in the urine are of bacterial origin.