title: Antioxidant activity of polyphenols from seeds of Vitis amurensis in vitro.
abstract: OBJECTIVE
  To study the antioxidant action of five polyphenols (+) catechin, procyanidin B2, procyanidin B5, procyanidin B5 3'-O-gallate, and amurensisin isolated from the seeds of Vitis amurensis.
  
  
  METHODS
  The mouse liver homogenate lipid peroxidation assay was applied for the evaluation of the antioxidant activity in vitro.
  
  
  RESULTS
  (+) Catechin, procyanidin B2, procyanidin B5, procyanidin B5 3'-O-gallate, and amurensisin showed antioxidant activity with the IC50 values of 0.47, 0.25, 0.10, 0.02, and 0.03 mmol/L, respectively. The IC50 value of vitamin E used as a positive control was 0.13 mmol/L. The structural activity relationship was also analyzed. Procyanidins carrying a galloyl group possessed higher anti-lipid peroxidation activities. All dimers were found to be more potent than the non-galloylated momomer such as (+) catechin. However, the activity of the 4-->6 linked dimer seemed more preferable than 4-->8 linked dimer.
  
  
  CONCLUSIONS
  Procyanidin B5, procyanidin B5 3'-O-gallate, and amurensisin showed a more antioxidant activity than vitamin E did, and their activity is dependent on their substitution and polymerization patterns.
authors.affiliation: State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210093, China.
authors.forename: J N
authors.initials: JN
authors.lastname: Wang
authors.forename: Y J
authors.initials: YJ
authors.lastname: Chen
authors.forename: Y
authors.initials: Y
authors.lastname: Hano
authors.forename: T
authors.initials: T
authors.lastname: Nomura
authors.forename: R X
authors.initials: RX
authors.lastname: Tan
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000302:isolation & purification / Q000494:pharmacology*; D044946:Biflavonoids; D002392:Catechin / Q000302:isolation & purification / Q000494:pharmacology; D004365:Drugs, Chinese Herbal / Q000737:chemistry*; D005419:Flavonoids; D066298:In Vitro Techniques; D008099:Liver / Q000378:metabolism; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D051379:Mice; D010636:Phenols / Q000302:isolation & purification / Q000494:pharmacology*; D011108:Polymers / Q000302:isolation & purification / Q000494:pharmacology*; D044945:Proanthocyanidins; D012639:Seeds / Q000737:chemistry
chemical_list: D000975:Antioxidants; D044946:Biflavonoids; D004365:Drugs, Chinese Herbal; D005419:Flavonoids; D010636:Phenols; D011108:Polymers; D044945:Proanthocyanidins; C479588:amurensisin; C479586:procyanidin B5 3'-O-gallate; C479580:procyanidin B2; C017674:procyanidin; D008315:Malondialdehyde; D002392:Catechin; C479582:procyanidin B5