title: Antioxidant effects of secondary metabolites from Geranium psilostemon.
abstract: An investigation was made of the effects on endogenous antioxidant enzyme activities and H2O2-induced lipid peroxidation inhibition in human red blood cells of the crude MeOH extract and its EtOAc, n-BuOH, and H2O sub-extracts obtained from aerial parts of Geranium psilostemon Ledeb., as well as compounds isolated from the most active EtOAc extract. Gallic acid (1), methyl gallate (2), pusilagin (3), 1,3,6-tri-O-galloyl-beta-glucopyranoside (4), 1,2,3,4,6-penta-O-galloyl-beta-glucopyranoside (5), kaempferol (6), quercetin (7), kaempferol 7-O-alpha-rhamnopyranoside (8), and quercetin 7-O-alpha-rhamnopyranoside (9) were isolated from the aerial parts of the title plant, and their structures identified from spectroscopic (UV, 1D- and 2D- NMR) and spectrometric (TOF-MS) data. All extracts and isolated compounds inhibited H2O2-induced lipid peroxidation and also enhanced the activity of superoxide dismutase (SOD) and catalase (CAT).
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Hacettepe University, 06100 Ankara, Turkey. didems@hacettepe.edu.tr
authors.forename: Didem
authors.initials: D
authors.lastname: Söhretoğlu
authors.forename: Suna Atasayar
authors.initials: SA
authors.lastname: Sabuncuoğlu
authors.forename: M Koray
authors.initials: MK
authors.lastname: Sakar
authors.forename: Hilal
authors.initials: H
authors.lastname: Ozgüneş
authors.forename: Olov
authors.initials: O
authors.lastname: Sterner
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000378:metabolism*; D004912:Erythrocytes / Q000187:drug effects / Q000378:metabolism; D031315:Geranium / Q000737:chemistry* / Q000378:metabolism*; D006801:Humans; D006861:Hydrogen Peroxide; D015227:Lipid Peroxidation; D035261:Plant Components, Aerial / Q000737:chemistry
chemical_list: D000975:Antioxidants; D006861:Hydrogen Peroxide