Chemical Composition, and Antibacterial (Against Staphylococcus aureus) and Free-Radical-Scavenging Activities of the Essential Oil of Scrophularia amplexicaulis Benth

Chemical composition of the essential oil obtained from the aerial parts of Scrophularia amplexicaulis Benth. was analyzed, for the first time, by the gas chromatography/mass spectrometry (GC-MS) and gas chromatography/flame ionization detection (GC-FID). A total yield of 3 mg of essential oil per100 g of plant dry mass was obtained, and 27 compounds were identified, representing 97.7% of total oil. The essential oil were characterized by a high content of oxygenated monoterpenes and phenolic derivatives. The main constituents were eugenol (53.8%), eugenol acetate (24.5%), β-caryophyllene (5.7%), caryophyllene oxide (6.4%) and aromadendrene oxide II (2.1%). The antimicrobial activity of the essential oil was tested against Staphylococcus aureus using the well diffusion method, and the free-radical-scavenging activity was assessed by the 2,2-diphenyl-picryl-hydrazyl (DPPH) assay .