Differential Cytotoxic Activity of Essential Oil of Lippia citriodora from Different Regions in Morocco.

The aim of this work was to investigate the cytotoxic effect of the essential oil of dried leaves of Lippia citriodora (H.B. & K.) harvested in different regions of Morocco. This effect was evaluated against the P815 murine mastocytoma cell line using the MTT assay. Interestingly, this work demonstrated for the first time that these essential oils exhibited a strong cytotoxic activity against the P815 cell line, with IC50 values ranging from 7.75 to 13.25 μg/ml. This cytotoxicity began early and increased in a dose- and time-dependent manner. The chemical profile of these essential oils was analyzed by gas chromatography coupled to mass spectrometry. Importantly, the difference in terms of major components' contents was not significant suggesting probably that the differential cytotoxicity between these essential oils could be attributed to the difference in the content of these essential oils in minor compounds, which could interact with each other or with the main molecules. Finally, this study demonstrated for the first time that essential oils of L. citriodora from different regions in Morocco induced apoptosis against P815 tumor cell line.