EFFECTS OF ENVIRONMENT AND DEVELOPMENT STAGE ON PHENOLIC CONTENT AND ANTIOXIDANT ACTIVITIES OF MENTHA PULEGIUM L.

Abstract

ABSTRACT We investigated the relative contributions of the environment and development stage on total polyphenols, flavonoids and condensed tannins contents, as well as 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide scavenging activities in four Tunisian Mentha pulegium. Shoot total phenolics and antioxidant capacities were significantly dependent on environment, development stage and their interaction. Environment effects were considerably larger than development stage effects for total phenolics, flavonoids, DPPH and superoxide scavenging capacities, whereas development stage was much stronger than environment for tannin content and, although small, interaction effects of the two factors (environment and development stage) were significant for all antioxidant properties analyzed. The highestantioxidant activities were related to high phenolic contents. Three behaviors were revealed; the best antioxidant capacities in Soliman at floral bud stage, followed by Takelsa and the lowest potentialities (Bouarada and Jdeida). These findings indicate that antioxidant properties of M. pulegium were respectively influenced by environment, development stage and their interaction. PRACTICAL APPLICATION Mentha pulegium L. belonging to the Lamiaceae family, which is a highly advanced and homogeneous family, is largely used in food preparation, perfumery, pharmaceutical products and as an insect repellent. In traditional medicine, M. pulegium essential oil is used for digestive, liver and gallbladder disorders, for gout colds and increased micturition and externally for skin diseases (Gruenwald et al. 1998). M. pulegium is a folkloric medicinal plant with interesting shoot antioxidant properties. According to our results, high antioxidant properties of the leaves of M. pulegium might be beneficial to the antioxidant activity.