期刊
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
卷 60, 期 14, 页码 3693-3699出版社
AMER CHEMICAL SOC
DOI: 10.1021/jf204826e
关键词
antioxidants; DPPH radical scavenging activity; density functional theory; bond dissociation enthalpy; spin density; ionization potential; proton affinity
资金
- Council of Scientific and Industrial Research (CSIR), Government of India [NWP-53]
- UGC
Structural, electronic, and energetic characteristics of tricin, tricin-4'-O-(erythro-beta-guaiacylglyceryl)ether (TEGE), and tricin-4'-O-(threo-beta-guaiacylglyceryl)ether (TTGE), isolated from Njavara rice bran have been studied using DFT to explain their experimentally determined radical scavenging activity (EC50 values) in comparison with known standards such as quercetin, myricetin, and catechin. Among the three mechanisms proposed for explaining the antioxidant activity, proton coupled-electron transfer (PC-ET), sequential proton loss electron transfer (SPLET), and electron transfer-proton transfer (ET-PT), our results support the second one. The O-H bond dissociation enthalpy (BDE) and the spin density on the oxygen with the radical character are excellent descriptors of radical scavenging activity. BDE (in kcal/mol) increased in the order myricetin (74.6) < quercetin < catechin (78.3) < tricin (81.5) < TTGE (90.6) < TEGE (91.1), while the EC50 increased exponentially with increase in BDE, 20.51, 42.98, 45.07, 90.39, 208.01, and 352.04 mu g/mL for myricetin, quercetin, catechin, tricin, TTGE, and TEGE, respectively.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据