title: Isolation and identification of phenolic compounds from Hypericum richeri Vill. and their antioxidant capacity.
abstract: The chemical composition and free radical scavenging properties of the MeOH extract of Hypericum richeri and its subsequent CHCl(3), n-BuOH, EtOAc and aqueous extracts were investigated. Four quercetin-3-O-glycosides, three myricetin-3-O-glycosides, 3-O- and 5-O-caffeoylquinic acid, quercetin, I3,II8-biapigenin, pseudohypericin and hypericin were identified. The constituents of the extracts were quantified using HPLC-DAD (high-performance liquid chromatography-diode array detector). Isolation of the compounds from n-BuOH and EtOAc extracts was conducted by column chromatography. Antioxidant capacity of the extracts was evaluated by superoxide radical and ABTS√(+) scavenging assays and inhibition of lipid peroxidation. The EtOAc extract of H. richeri was the most potent antioxidant in all experiments. Free radical scavenging compounds were identified by HPLC-DPPH√ (high-performance liquid chromatography-2,2-diphenyl-1-picrylhydrazyl) post-column derivatisation method, where all phenolic compounds except I3,II8-biapigenin exhibited radical scavenging properties. This is the first report of the presence of myricetin-3-O-rutinoside, myricetin-3-O-galactoside, myricetin-3-O-glucoside, 5-O-caffeoylquinic acid and I3,II8-biapigenin in H. richeri.
authors.affiliation: Institute for Medicinal Plant Research Dr Josif Pančić, Belgrade, Serbia.
authors.forename: Gordana
authors.initials: G
authors.lastname: Zdunić
authors.forename: Dejan
authors.initials: D
authors.lastname: Gođevac
authors.forename: Katarina
authors.initials: K
authors.lastname: Šavikin
authors.forename: Miroslav
authors.initials: M
authors.lastname: Novaković
authors.forename: Slobodan
authors.initials: S
authors.lastname: Milosavljević
authors.forename: Silvana
authors.initials: S
authors.lastname: Petrović
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification*; D002851:Chromatography, High Pressure Liquid; D002853:Chromatography, Liquid; D020902:Hypericum / Q000737:chemistry*; D015227:Lipid Peroxidation; D013058:Mass Spectrometry; D008954:Models, Biological; D010636:Phenols / Q000737:chemistry* / Q000302:isolation & purification*
chemical_list: D000975:Antioxidants; D010636:Phenols