Phytochemicals, antioxidant and anti-proliferative activities of Myrtus communis L. genotypes from Tunisia

Myrtle (Myrtus communis L.) has long been regarded as a medicinal and aromatic plant. The analysis of phenolic and terpenic compounds contained in the leaf extracts of three Myrtle genotypes showed their richness in monoterpene hydrocarbons (48, 32%, 83.77%), flavonols, and hydrolysable tannins. Phenolic profiles and volatile compounds varied significantly among genotypes. All leaves extracts revealed excellent DPPH scavenging activity and β-carotene bleaching inhibition capacity (IC50=3.81 µg/ml, IC50= 3.58 µg/ml, respectively). The MTT metabolism assay demonstrated the efficacy of M. communis genotypes against PC12 cancer cell proliferation and their safety towards normal cells. Caspases 3/7 induction, apoptosis and intracellular ROS accumulation of treated cancer cell lines proved the cytotoxic effect of M. communis genotypes. This cytotoxic activity could be related to the antioxidant properties of the studied extracts. Antioxidant and antiproliferative activities varied significantly among genotypes. Such variation is attributed to chemical composition differences. Our results highlighted the interest of use of M. communis extracts as an industrial crop or as an ingredient in functional foods.