- Antioxidant effect of hydroxytyrosol, a polyphenol from olive oil: scavenging of hydrogen peroxide but not superoxide anion produced by human neutrophils. O'Dowd, Y., Driss, F., Dang, P.M., Elbim, C., Gougerot-Pocidalo, M.A., Pasquier, C., El-Benna, J. Biochem. Pharmacol. (2004)