Scavenging Of Toxic Acrolein By Resveratrol And Hesperetin: Reaction Kinetics And Adducts Identification

The objective of this study was to investigate the ability of resveratrol and hesperetin to scavenge acrolein in pH 7.4 at 37 o C. Acrolein is a toxic α, β‐unsaturated aldehyde that exists in human body and foods due to lipid oxidation. At equal molar concentrations, resveratrol and hesperetin quenched 93.6% and 94.8% of acrolein in 12 hours, respectively. These were accompanied by a decrease of 55.0% resveratrol and 30.7% hesperetin. A resveratrol‐acrolein adduct and a hesperitin‐acrolein adduct were isolated using Sephadex LH‐20, reversed and normal phase chromatography. Their structures were elucidated by MS and NMR spectrum. It was shown that an acrolein reacted with a benzene ring of resveratrol at the C2 and C3 positions through nucleophilic addition to form an additional heterocyclic ring. A similar monoacrolein‐conjugated adduct was identified for hesperetin in a mixture of epimers, where an acrolein added onto the C5 and C6 positions on the A‐ring to form a heterocyclic ring. Yield of adducts was low at pH=5.4 but increased at the pH 7.4 and 8.4. Higher pH also promoted the formation of di‐acrolein adducts. The scavenging of acrolein by resveratrol and hesperetin followed fifth and third order kinetics at pH 7.4, respectively. These results suggest that resveratrol and hesperetin exert health benefits in part through neutralizing toxic acrolein in human body.