Abstract
This work was carried out in order to valorize a medicinal and aromatic plant of Tunisia: Mentha aquatica. Mentha aquatica dried leaves were submitted to hydrodistillation in a Clevenger apparatus. Their essential oil (EO) composition was analysed by gas chromatography coupled to mass spectrometry (GC-MS). The antioxidant activity of Mentha aquatica Essential oil was evaluated by DPPH free radical -scavenging method. We tested also its biological activity against some microorgnisms : Escherichia Coli ATCC 25922, Staphylococcus aureus ATCC 29213 and Bacillus and also a fungi : candida. Results showed that the most abundant volatile compound of M. aquatica Essential oil was pulegone with a percentage of 39.36 %. It was followed by menthone accounting for 27.69 % of total volatile compounds. Furthermore, oxygenated monoterpenes accounting for 91.4 % of total volatiles constituted the prominent chemical class of this volatile oil. Respective amounts of hydrocarbon monoterpenes and sesquiterpenes were of 3.51 and 5.06 %. The half maximal inhibitory concentration (IC50) of the M. aquatica Essential oil was similar to that of trolox (8 μg /ml ) which is a synthetic molecule with a high antioxidant activity used as a blanck, The antibacterial assay showed that M. aquatia Essential oil was active against Staphylococcus ATCC, E. coli and Bacillus but it doesn't show an inhibitory effect against Candida.