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.