Acta Phys. -Chim. Sin. ›› 2013, Vol. 29 ›› Issue (07): 1421-1432.doi: 10.3866/PKU.WHXB201304222

• THEORETICAL AND COMPUTATIONAL CHEMISTRY • Previous Articles     Next Articles

Radical Scavenging Activity of Myricetin

XIE Hu-Jun1, MOU Wang-Shu1, LIN Fu-Rong1, XU Jie-Hui1, LEI Qun-Fang2   

  1. 1 Department of Applied Chemistry, Zhejiang Gongshang University, Hangzhou 310035, P. R. China;
    2 Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. China
  • Received:2013-02-21 Revised:2013-04-22 Published:2013-06-14
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21203166, 21073164), Natural Science Foundation of Zhejiang Province, China (Y4100620, LY12B04003), and Student Innovation Foundation of Zhejiang Province, China (2012R408007).

Abstract:

Density functional theory (DFT) calculations have been performed to explore the molecular structure, electronic structure, and O-H bond dissociation enthalpy of myricetin. Possible antioxidation mechanisms between lipid peroxide radical CH3OO· and myricetin have been discussed. DFT calculations at the M06-2X/6-31++G(d,p) level indicated that the 4'-OH group of myricetin is the most active site on the basis of the stability of dehydrogenated myricetin radicals, O-H bond dissociation enthalpy, and hydrogen abstraction activation barrier, as well as kinetic data for myricetin determined at different temperatures. The relatively high activity of the 4'-OH site can be ascribed to weak hydrogen-bonding interactions between the oxygen radical of the reactive OH group and the adjacent OH group in the B-ring, which is retained upon going from free myricetin to reactant complex to product according to atoms in molecule (AIM) analysis. The hydrogen-bond helps to stabilize the electronic deficiency generated on the oxygen radical during the hydrogen abstraction reaction. All calculations are in agreement with the structure-activity relationship previously established for myricetin by considering its antioxidant activity. Present calculations provide theoretical basis for the designing new antioxidants.

Key words: DFT calculation, Reaction mechanism, Myricetin, Antioxidant activity, Bond dissociation enthalpy

MSC2000: 

  • O641