Chemical Composition, Antibacterial, and Antifungal activities of the Essential Oil of Thymus numidicus Poiret from Algeria

The present study has been carried on Numidian thyme (Thymus numidicus), a medicinal plant belonging to the Lamiaceae family. Numidian thyme is an Algero-Tunisian endemic species. The essential oil was extracted from the leaves of the plant harvested in wild habitat at Tifrit (Tizi Ouzou, Algeria), by steam hydrodistillation with 1.58% yield. Analysis by GC–MS (Gas chromatography-mass spectrometry) of the essential oil helped to identify more than 70 compounds and to classify it as a thymol chemotype. The major components of the oil were: thymol (40.40%) and carvacrol (13.37%). Antibacterial and antifungal activities of Thymus numidicus essential oil was studied in vitro on three bacterial (Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa) and one fungal strains (Candida albicans). The results showed that this essential oil has a wide spectrum of antimicrobial activity on Gram-negative and Gram-positive bacteria and possesses strong antifungal activity on Candida. This activity is probably due mainly to the predominant presence of thymol, and it is more important on fungi than bacteria. Results of this study look promising for the valuation of medicinal plants with the aim of promoting the Algerian pharmaceutical industry.