title: Isolation and purification of antioxidative isomeric polyphenols from the roots of Parthenocissus laetevirens by counter-current chromatography.
abstract: Upright counter-current chromatography (CCC) with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (1:2:1:2, v/v/v/v) was applied to the isolation and purification of polyphenols from the roots of Parthenocissus laetevirens. Two cis-trans isomeric resveratrol dimers - quadrangularin A and parthenocissin A - were obtained from the crude sample in a one-step separation, with purities of 95.4 and 97.6%, respectively, as determined by HPLC. The structures of these two compounds were identified by (1)H NMR and (13)C NMR. Furthermore, their antioxidant activities were determined by beta-carotene bleaching assay. The antioxidant activities of quadrangularin A and parthenocissin A were higher than that of vitamin C in this model.
authors: Department of Chemistry, Zhejiang University, Hangzhou 310027, China.
authors: Shan
authors: S
authors: He
authors: Yanbin
authors: Y
authors: Lu
authors: Bin
authors: B
authors: Wu
authors: Yuanjiang
authors: Y
authors: Pan
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification*; D003377:Countercurrent Distribution / Q000379:methods*; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification*; D015394:Molecular Structure; D010636:Phenols / Q000737:chemistry / Q000302:isolation & purification*; D018517:Plant Roots / Q000737:chemistry*; D059808:Polyphenols; D015203:Reproducibility of Results; D027844:Vitaceae / Q000737:chemistry*; D019207:beta Carotene / Q000737:chemistry
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D010636:Phenols; D059808:Polyphenols; D019207:beta Carotene