title: Metabolism of hop-derived bitter acids.
abstract: In this study, in vitro metabolism of hop-derived bitter acids was investigated. Besides their well-known use as bitter compounds in beer, in several studies, bioactive properties have been related to these types of molecules. However, scientific data on the absorption, distribution, metabolism, and excretion aspects of these compounds are limited. More specific, in this study, α-acids, β-acids, and iso-α-acids were incubated with rabbit microsomes, and fractions were subjected to LC-MS/MS analysis for identification of oxidative biotransformation products. Metabolism of β-acids was mainly characterized by conversion into hulupones and the formation of a series of tricyclic oxygenated products. The most important metabolites of α-acids were identified as humulinones and hulupones. Iso-α-acids were found to be primarly metabolized into cis- and trans-humulinic acids, next to oxidized alloiso-α-acids. Interestingly, the phase I metabolites were highly similar to the oxidative degradation products in beer. These findings show a first insight into the metabolites of hop-derived bitter acids and could have important practical implications in the bioavailability aspects of these compounds, following ingestion of hop-based food products and nutraceuticals.
authors.affiliation: Laboratory of Pharmacognosy and Phytochemistry, Faculty of Pharmaceutical Sciences, Ghent University (UGent), Ghent, Belgium. ko.cattoor@UGent.be
authors.forename: Ko
authors.initials: K
authors.lastname: Cattoor
authors.forename: Michael
authors.initials: M
authors.lastname: Dresel
authors.forename: Lies
authors.initials: L
authors.lastname: De Bock
authors.forename: Koen
authors.initials: K
authors.lastname: Boussery
authors.forename: Jan
authors.initials: J
authors.lastname: Van Bocxlaer
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Remon
authors.forename: Denis
authors.initials: D
authors.lastname: De Keukeleire
authors.forename: Dieter
authors.initials: D
authors.lastname: Deforce
authors.forename: Thomas
authors.initials: T
authors.lastname: Hofmann
authors.forename: Arne
authors.initials: A
authors.lastname: Heyerick
mesh_terms: D000143:Acids / Q000737:chemistry / Q000378:metabolism*; D000818:Animals; D002853:Chromatography, Liquid; D006801:Humans; D027582:Humulus / Q000737:chemistry / Q000378:metabolism*; D008861:Microsomes / Q000737:chemistry / Q000378:metabolism; D011817:Rabbits; D053719:Tandem Mass Spectrometry; D013649:Taste
chemical_list: D000143:Acids