Computational study of the hydrogen peroxide scavenging mechanism of allyl methyl disulfide, an antioxidant compound from garlic

Abstract

Although many sulfur containing garlic compounds present antioxidant activity, little is known about molecular mechanisms through which these compounds react with reactive oxygen species. In this work, the reactivity and the hydrogen peroxide scavenger reaction mechanisms (including thermodynamics and kinetics aspects) of allyl methyl disulfide in aqueous phase are studied employing density functional theory computational methods. Three reactive sites susceptible for electrophilic attack are found over sulfur atoms and the double bond allyl moiety. For each detected site, one redox reaction is proposed and analyzed. All reactions are thermodynamically feasible, whereas attack over the methyl bound sulfur atom is kinetically favored.