Radical scavenging activity of lipophilic antioxidants and extra-virgin olive oil by isothermal calorimetry

摘要

Highlights?A calorimetric adaptation of the classical stress testing with AIBN is proposed.?The assay evaluates the radical scavenging activity of lipophilic antioxidants.?Delay of the exothermal peak of AIBN measures the radical scavenging activity.?Methanol interferes because it can participates in the hydrogen-atom-transfer process.?Radical scavenging activity of extra virgin olive oil correlates with polyphenol content.AbstractThis work proposes an oxidative stress test based on the measurement of the heat generated during the reaction of AIBN (2,2′-azobis(2-methylpropionitrile)) with lipophilic antioxidants. Without antioxidants, AIBN generates an exothermic peak (induction period=7.50h, peak time=8.55h, area=3.6kJmol?1of AIBN, at 50°C). In the presence of anti