Pulegone/MENT ratio as an indicator of antioxidant activity for the selection of industrial cultivars of peperina with high antioxidant potential

Abstract

The essential oil of peperina has antioxidant properties for industrial use, but the choice of cultivars with the highest antioxidant efficacy remains undetermined. The aim of the present study was to determine the direct and indirect antioxidant activity of three peperina cultivars (Calamintha nepeta, Hedeoma multiflorum and Minthostachys verticillata) and to analyse the response of a potential antioxidant activity indicator based on the Pulegone/Menthone and Isomenthone (PUL/MENT) ratio, obtained from chemical composition analysis. The antioxidant properties were evaluated by free radical scavenging activity, total phenol content, chemical (peroxide, anisidine and conjugated dienes values) and volatiles oxidation indicators in an accelerated oxidation test at 60 °C for 28 days. The C. nepeta variety showed the highest antioxidant activity and the highest PUL/MENT ratio value (5.1) with respect to H. multiflorum (1.3) and M. verticillata (2.0). The indicator of the PUL/MENT ratio can be used as a reference indicator of antioxidant activity for the selection of industrial cultivars with high antioxidant activity when they have a ratio with a value higher than 2.0 as a reference point in their chemical composition.