Repair Activity of trans-Resveratrol toward 2'-Deoxyguanosine Radicals.

In the present study, the repair activity of trans-resveratrol toward 2'-deoxyguanosine (dGuo) radicals in polar and nonpolar solvents was studied using density functional theory. The hydrogen transfer/proton coupled electron transfer and single electron transfer (SET) mechanisms between trans-resveratrol and dGuo-radicals were considered. Taking into consideration the molar fraction of neutral trans-resveratrol (ROH) and anionic trans-resveratrol (RO-), the overall rate constants for repairing dGuo-radicals by trans-resveratrol are 9.94 × 108 and 2.01 × 109 dm3 mol-1 s-1 in polar and nonpolar solvents, respectively, and the overall rate constant of repairing cation radical (dGuo•+) by trans-resveratrol via an SET mechanism is 7.17 × 109 dm3 mol-1 s-1. The repair activity of RO- toward dGuo-radicals is better than that of ROH, but the repair activity of ROH toward dGuo•+ is better than that of RO-. Unfortunately, neither ROH nor RO- can repair the 2'-deoxyribose radicals of dGuo. It can therefore be concluded that trans-resveratrol is an effective antioxidant for repairing base radicals of dGuo and dGuo•+. The study can help us understand the repair activity of trans-resveratrol toward dGuo radicals.