The hydroperoxyl radical scavenging activity of natural hydroxybenzoic acids in oil and aqueous environments: Insights into the mechanism and kinetics.

Foods that contain hydroxybenzoic acid derivatives (HBA) include red fruits, black radish, onion, and potato peel. HBA are widely known for their anti-inflammatory, anti-cancer, and especially antioxidant capabilities; however, a comprehensive study of the mechanism and kinetics of the antiradical action of these compounds has not been performed. Here, we report a study on the mechanisms and kinetics of hydroperoxyl radical scavenging activity of HBA by density functional theory (DFT) calculations.

Oxoberberine: a promising natural antioxidant in physiological environments.

Oxoberberine (OB, 2,10-dihydroxy-3,9-dimethoxy-8-oxo-protoberberine, artathomsonine), which was isolated from Artabotrys thomsonii, was shown to exhibit potent antioxidant activity , however that is the only reported evidence of the radical scavenging activity of this compound thus far. In the present study, thermodynamic and kinetic calculations were used to determine the free radical scavenging activity of OB against a range of biologically important species, under physiological conditions. In the first part the activity is calculated against the HOO˙ radical that is both biologically important and a reference radical for comparison.