Essential oil constituents and biological activities of leaf extracts of semenovia suffruticosa from Iran

Semenovia suffruticosa (Freyn et Bornm.) Manden. is one of the species of genus Semenovia (Apiaceae family). The essential oil of S. suffruticosa was obtained by hydrodistillation and analysed by gas chromatography coupled to mass spectrometry (GC/MS). The main components were cis-β-ocimene (12.9%), linalool (9.5%), γ-terpinene (9.0%) and α-terpinolene (7.4%), representing the 38.8% of the oil. Antibacterial activity of S. suffruticosa ethanol, chloroform, ethyl acetate and aqueous leaf extracts was evaluated for the first time. The various extracts were tested by the disc-diffusion assay for antimicrobial activity against common animal and human infectious bacteria. Pseudomonas aeruginosa exhibited the highest sensitivity against the extracts, with a 13-15 mm zone of inhibition. Antiradical activity of S. suffruticosa ethanol, chloroform, ethyl acetate and aqueous leaf extracts was determined by DPPH (2,2-diphenyl-1-picrylhydrazyl) radical, FRAP (ferric reducing antioxidant power) and β-carotene/linoleic acid assays. Ethanol extract was the most powerful free radical scavenger in all these methods. These results, though preliminary, suggest that leaf extracts of S. suffruticosa exert promising antioxidant and antibacterial activities.