Essential oil composition and antioxidant and antimicrobial properties of the aerial parts of Salvia eremophila Boiss. from Iran

The essential oil composition and in vitro antioxidant and antimicrobial activity of the essential oil and methanol extract of Salvia eremophila were evaluated in this research. GC and GC/MS analysis of the plant essential oil resulted in the identification of 28 compounds representing 99.24% of the oil. Borneol (21.83%), α-pinene (18.80%), bornyl acetate (18.68%) and camphene (6.54%) were detected as the major components consisting 65.85% of the oil. The plant essential oil and methanol extract were also subjected to screenings for the evaluation of their antioxidant activities using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and β-carotene–linoleic acid tests. While the plant essential oil showed only weak antioxidant activities, its methanol extract was considerably active in both DPPH (IC₅₀ = 35.19 μg/ml) and β-carotene–linoleic acid (inhibition percentage: 72.42%) tests. Appreciable total phenolic content (101.25 μg/mg) was also detected for the plant methanol extract as gallic acid equivalent in the Folin–Ciocalteu test. The plant was also screened for its antimicrobial activity and good to moderate inhibitions were recorded for its essential oil and methanol extract against most of the tested microorganisms.