Chemical composition, antibacterial and antifungal activities of Saudi Arabian Mentha longifolia L. essential oil

Objective: To investigate the chemical composition, in vitro antibacterial and antifungal activity of Mentha longifolia L. essential oils using aqueous extract. Methods: Mentha longifolia L. essential oils were extracted using hydrodistillation with Clevenger apparatus for 3 h and the yield of the essential oil was calculated. Essential oils were qualitatively and quantitatively analyzed with gas chromatography and gas chromatographymass spectrometer. For these essential oils, antibacterial and antifungal activity against human pathogens were evaluated. Results: Nineteen chemical constituents representing 99.72% of the essential oil were found, comprising menthone (39.55%), isopulegone (30.49%), eucalyptol (10.38%), and α-terpineol (3.15%); these were major components, and others were minor components. The essential oil showed strong antibacterial activity against Staphylococcus aureus [(35.24 � 0.13) mm], Enterococcus faecalis [(32.12 � 0.12) mm] and Bacillus cereus [(30.06 � 0.04) mm], as well as antifungal activity against Aspergillus flavus [(38.02 � 0.06) mm], Alternaria alternaria [(35.26 � 0.12) mm], and Penicillum spp [(34.14 � 0.02) mm]. Conclusions: It seems that the essential oils derived from the Mentha longifolia L. species could be used as a natural source of antimicrobial agents.