title: Ingestion of oregano extract increases excretion of urinary phenolic metabolites in humans.
abstract: Despite the promising antioxidant action of Lamiaceae herbs in vitro, human studies on these potential sources of dietary antioxidants have remained scarce. In this work, the phenolic acids recovered in human urine after single ingestion of Origanum onites extract were analyzed. The excretion was increased 4- and 2-fold during 0-24 and 24-48 h of the follow-up, respectively. The mean increase in the excretion of phenolic compounds exceeded the ingested amount of identified phenolic acids. The result can be partly explained by rosmarinic acid, the main identified phenolic constituent in the extract, as well as flavonoids present in minor amounts, presumably being metabolized into a double amount of simple phenolic metabolites. Furthermore, unidentified phenolic constituents in the extract partly contribute to the excretory increase. The main metabolite, p-hydroxybenzoic acid, was excreted rapidly. The results show that constituents of oregano extract and, in particular, their metabolites may contribute to the dietary intake of phenolic antioxidants.
authors.affiliation: Division of Pharmaceutical Biology, Faculty of Pharmacy, University of Helsinki, Finland.
authors.forename: Anna
authors.initials: A
authors.lastname: Nurmi
authors.forename: Tarja
authors.initials: T
authors.lastname: Nurmi
authors.forename: Jaakko
authors.initials: J
authors.lastname: Mursu
authors.forename: Raimo
authors.initials: R
authors.lastname: Hiltunen
authors.forename: Sari
authors.initials: S
authors.lastname: Voutilainen
mesh_terms: D000146:Acids, Carbocyclic / Q000652:urine; D000328:Adult; D002934:Cinnamates / Q000652:urine; D053630:Depsides; D019587:Dietary Supplements; D005260:Female; D005419:Flavonoids / Q000032:analysis; D006801:Humans; D008297:Male; D031341:Origanum / Q000737:chemistry*; D010636:Phenols / Q000032:analysis / Q000652:urine*; D010936:Plant Extracts / Q000008:administration & dosage* / Q000737:chemistry; D000097123:Rosmarinic Acid
chemical_list: D000146:Acids, Carbocyclic; D002934:Cinnamates; D053630:Depsides; D005419:Flavonoids; D010636:Phenols; D010936:Plant Extracts; D000097123:Rosmarinic Acid