title: Antimutagenicity of hops (Humulus lupulus L.): bioassay-directed fractionation and isolation of xanthohumol.
abstract: Bioassay-directed fractionation with a Salmonella/microsomal assay against the food borne mutagen 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) was used to identify antimutagenic components of hops. Hops pellets extracted with diethylether showed antimutagenic activity against mutations induced by IQ. Fractionation of the diethylether extract (DE) by column chromatography, followed by semi-preparative HPLC yielded two fractions (E4b and E4d) with strong antimutagenic activity against IQ induced mutations. Separation of fraction E4b resulted in inactive fractions, while fraction E4d has been identified to be xanthohumol. In mammalian test system with human hepatoma HepG2 cells fraction E4d at 10mug/ml completely prevented formation of IQ induced DNA damage. These results indicate that xanthohumol is a very promising potential protective agent against genotoxicity of food borne carcinogens, which warrants further investigation.
authors.affiliation: Department of Pharmaceutical Biology, Faculty of Pharmacy, University of Ljubljana, Askerceva 7, 1000 Ljubljana, Slovenia.
authors.forename: Javor
authors.initials: J
authors.lastname: Kac
authors.forename: Janja
authors.initials: J
authors.lastname: Plazar
authors.forename: Ales
authors.initials: A
authors.lastname: Mlinaric
authors.forename: Bojana
authors.initials: B
authors.lastname: Zegura
authors.forename: Tamara T
authors.initials: TT
authors.lastname: Lah
authors.forename: Metka
authors.initials: M
authors.lastname: Filipic
mesh_terms: D015112:4-Nitroquinoline-1-oxide / Q000633:toxicity; D000818:Animals; D016587:Antimutagenic Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D001681:Biological Assay / Q000379:methods; D045744:Cell Line, Tumor; D004249:DNA Damage; D004986:Ether / Q000737:chemistry; D005419:Flavonoids; D006801:Humans; D027582:Humulus / Q000737:chemistry*; D008861:Microsomes; D009153:Mutagens / Q000494:pharmacology; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology*; D011427:Propiophenones / Q000302:isolation & purification / Q000494:pharmacology*; D011804:Quinolines / Q000633:toxicity; D051381:Rats; D012475:Salmonella / Q000737:chemistry
chemical_list: D016587:Antimutagenic Agents; D005419:Flavonoids; D009153:Mutagens; D010936:Plant Extracts; D011427:Propiophenones; D011804:Quinolines; D004986:Ether; C029216:2-amino-3-methylimidazo(4,5-f)quinoline; D015112:4-Nitroquinoline-1-oxide; C104536:xanthohumol