Kaltoum LadmiBahi RachaaSupervisor:Zitouni Ouassila2024-07-182024-07-182024633/178-Thttp://dspace.univ-khenchela.dz:4000/handle/123456789/6087This study aims to evaluate the antioxidant power and antibacterial activity of essential oils extracted from a plant belonging to the genus Thymus, collected in the Chechar region. The oil is extracted by hydrodistillation from a aerial parts of the plant (stem, leaf, flower). The in-vitro antioxidant activity of the obtained extracts was evaluated using the DPPH method. According to the results obtained, the highest concentration of antiradical essential oil was found to be 57.30 μl . Using the disk diffusion method to assess the antibacterial activity of the essential oils alone, a remarkable effect of the Thymus oil collected in Chechar on Staphylococcus aureus was observed, with an inhibition zone diameter of 22.01 mm. There was a moderate effect on Pseudomonas aeruginosa and a weak effect on Escherichia coli. The aromatogram on solid medium (disk method) was used to evaluate the antimicrobial efficacy of Thymus essential oils alone and in synergy with two antibiotics, oxacillin and gentamicin, on two bacterial strains, Staphylococcus aureus and Escherichia coli. In conclusion, the study of the antioxidant and antibacterial activity of Thymus essential oils offers promising prospects in the field of biomedical research.frThesis