Chemical composition, antimicrobial and antioxidant activities of the essentials oils from flowers of Salvia sharifii

Abstract
The present study is the first investigation of chemical composition, antioxidant and antimicrobial activities of the volatile oils from Salvia sharifii in Tunisia. The obtained results show that essential oils from Tunis locality were most complex and present 35 compounds representing 96.83% of the total oil composition. The major components of the studied oils in this site are Linalool (32.9%) and the green leaf volatiles; hexyl isolaverate (15.4%) and hexyl-2-methyl butanoate (10.9%) were detected as the major constituents of the oil. Considerable levels of antioxidant activities of the investigated essential oils were highlighted. Variations in antioxidant activities may be attributed to the concentrations of major components and the presence of some phenolic compounds like linalool. Our results showed strong activities of the investigated oils against all tested microorganisms. The antimicrobial test results showed that the oils had a great potential antimicrobial activity against all bacteria and fungal strains. Gram-positive bacteria are more sensitive to the investigated oil, with a range of 0.09 to 6.25 µL/mL than Gram-negative bacteria in the range, which is significantly higher from 1.56 to 25.00 µL/mL. The oil showed moderate antioxidant activities, (IC50 = 16.8 µg/mL) but good to moderate antimicrobial activity against most of the tested microorganisms.