title: Antioxidant activity of pine bark constituents.
abstract: A modified in vitro lipid peroxidation inhibition assay was used to guide the fractionation and the isolation of antioxidative principles of Fnnish pine bark extract. This approach yielded 3,4-dihydroxybenzoic acid (protocatechuic acid) and taxifolin-3-O-beta-glucopyranoside as major antioxidative compounds from the plant material. The structural elucidation of these compounds was undertaken with the help of HPLC-DAD and HPLC-ESI-MS analyses. Their IC50 values, in comparison to trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), were: trolox (1.78 +/- 0.56 microM) < protocatechuic acid (5.77 +/- 1.63 microM) < taxifolin-3-O-beta-glucopyranoside (16.30 +/- 1.98 microM). The method for the determination of antioxidant activity proved reproducible and quick for routine analyses with 96 well plates.
authors.affiliation: Department of Chemistry, University of Turku, 20014 Turku, Finland. amsale@utu.fi
authors.forename: Ammar
authors.initials: A
authors.lastname: Saleem
authors.forename: Henri
authors.initials: H
authors.lastname: Kivelä
authors.forename: Kalevi
authors.initials: K
authors.lastname: Pihlaja
mesh_terms: D000975:Antioxidants / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D002839:Chromans; D002851:Chromatography, High Pressure Liquid; D062385:Hydroxybenzoates; D007700:Kinetics; D015227:Lipid Peroxidation / Q000187:drug effects; D028223:Pinus / Q000737:chemistry*; D024301:Plant Bark / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D002839:Chromans; D062385:Hydroxybenzoates; C009091:protocatechuic acid; C010643:6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid