title: Antioxidation properties and mechanism of action of dihydromyricetin from Ampelopsis grossedentata.
abstract: OBJECTIVE
  To assess the antioxidative properties and the mechanism of action of dihydromyricetin (DMY) from Ampelopsis grossedentata.
  
  
  METHODS
  The antioxidative properties of DMY were measured by scavenging 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and inhibiting lipid peroxidation induced by FeSO4-edetic acid in linoleic acid. The mechanism of antioxidative properties of DMY was tested by measuring the chelating activities of DMY for Fe2+ with ultraviolet spectrum (UV) method.
  
  
  RESULTS
  The specific absorption of DPPH radical solution at 517 nm was reduced 73.3%-91.5% when DMY was added into the reaction solution in the concentration range from 0.01% to 0.04%. DMY was shown to greatly inhibit the increase of lipid peroxidation (LPO) values in linolei acid system catalyzed by FeSO4-edetic acid. The reaction rates (A532.min-1) of lipid peroxidation were 0.0021-0.0004 in the concentration range from 0.01% to 0.04% and the inhibition activities of DMY was found to be in a concentration-dependent manner. The mechanism of antioxidative properties of DMY was chelating Fe2+ in the Fe(2+)-dependent lipid peroxidation system.
  
  
  CONCLUSIONS
  DMY showed great antioxidative effect and would be a good natural antioxidant.
authors.affiliation: College of Food and Biological Engineering, South China University of Science and Technology, Guangzhou 510641, China. youshengzhang@263.net
authors.forename: You-sheng
authors.initials: YS
authors.lastname: Zhang
authors.forename: Zheng-xiang
authors.initials: ZX
authors.lastname: Ning
authors.forename: Shu-zhen
authors.initials: SZ
authors.lastname: Yang
authors.forename: Hui
authors.initials: H
authors.lastname: Wu
mesh_terms: D032421:Ampelopsis / Q000737:chemistry*; D000975:Antioxidants / Q000302:isolation & purification / Q000494:pharmacology*; D002614:Chelating Agents / Q000494:pharmacology; D044948:Flavonols / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D016166:Free Radical Scavengers / Q000302:isolation & purification / Q000494:pharmacology; D015227:Lipid Peroxidation / Q000187:drug effects*; D015394:Molecular Structure; D010946:Plants, Medicinal / Q000737:chemistry
chemical_list: D000975:Antioxidants; D002614:Chelating Agents; D044948:Flavonols; D016166:Free Radical Scavengers; C472036:dihydromyricetin