Chemical composition and variability of the essential oil of Thymus numidicus Poir. from Algeria

Abstract In a previous study, Thymus numidicus has showed a high antifungal activity. Here, GC/MS analysis was used for the chemical determination of the essential oil from T. numidicus. Samples were obtained by hydrodistillation from plants gathered in three different places during the biological cycle. Essential oils were high in phenolic monoterpens and in their precursors, and in non—phenolic oxygenated and non—oxygenated monoterpens. The arrangement of several statistical tools has enabled a relation between the chemical composition variation of essential oils during the biological cycle and the abiotic conditions of each place. Essential oils collected during the periods: end of March and end of April were low in monoterpens, high in oxygenated monoterpens and phenols. The periods corresponding to July were typical from the biological cycle end, with high level in p—cymene and low level in phenols and linalool.