Résumé
To isolate the essential oils of Origanum syriacum, Thymus decussatus and Salvia multicaulis and evaluate their antioxidative and hepatoprotective activities against paracetamol induced injury in primary-cultured rat liver cells. The essential oils isolated from Origanum syriacum, Thymus decussatus and Salvia multicaulis were analysed by GC-MS. Antioxidant activities of the essential oils were determined by DPPH scavenging activity [DPPH] and Trolox equivalent antioxidant capacity [TEAC] asssays. Conditions have been investigated to devise an in-vitro colorimetric MTT assay method for the hepatoprotective activity against paracetamol induced injury in primary-cultured rat liver cells. The major component of the essential oils of Origanum syriacum, Thymus decussatus was thymol 58.6% and 21.6% respectively. While the major component of Salvia multicaulis was camphor 39.8%. The antioxidant activity showed that the volatile oil of Origanum exhibited the highest activity followed by Thymus then Salvia. As for the hepatoprotective activity, the assay revealed that the volatile oil of Salvis multicaulis showed a suitable safety margin [the toxic concentration was 125 micro g/ml, while hepatoprotective concentration was only 25micro g/ml]. The essential oils of Origanum syriacum, Thymus decussatus and Salvia multicaulis exhibited remarkable antioxidant activity and significant hepatoprotective activity