This study aims to evaluate total phenolic content (TPC) and in vitro antioxydant activity (AA) of S. myrtifolia collected from Lebanon. TPC of S. myrtifolia were extracted by two solvents (methanol and water) and determined spectrophotometrically. The AA of both crude extracts were evaluated in vitro by 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity method. Extracts exhibit relatively high levels of phenolic compounds which range from 343 ± 7.53 to 441 ± 10.70 mg GAE g-1 DW depending on the solvent used. Both extracts exerted hydrogen-donating ability in the presence of DDPH stable radical with a remarkable AA for aqueous extract. This study demonstrate that S. myrtifolia is a resource of biological active compounds which can reduces the risk of diseases and its effects which correlated with the antioxidant compounds. تفاصيل المقالة