Reaction mechanism of ferulic acid scavenging OH and NO2 radicals: a theoretical study

As a derivative of cinnamic acid, ferulic acid (FA) is a bio-active ingredient of many foods and is considered to be a good natural antioxidant. A theoretical study on the reaction mechanism of FA scavenging two damaging radicals (center dot OH and center dot NO2) was investigated through the density functional theory (DFT) method. Two most possible reaction mechanisms, hydrogen atom transfer (HAT) and radical adduct formation (RAF), were studied. All possible reaction/attack sites were examined, and the corresponding pathways in both gaseous and aqueous medium were identified by thermodynamic and kinetic calculations. It was found that the most active site of FA scavenging center dot OH is the -OH group in benzene ring by HAT mechanism. While, for scavenging center dot NO2, the RAF reaction on the C = C double bond is the dominant channel in the aqueous phase.