Abstract
The essential oil of the aerial parts of Salvia bicolor Desf. growing in Egypt was obtained by hydrodistillation (0.3 % w/w) and analysed by gas chromatography and gas chromatography-mass spectroscopy. The antimicrobial activity of the essential oil of S. bicolor against seven bacteria and two yeast strains as well as its MIC against the susceptible microorganisms was determined. Thirty-three components were identified, representing 98.73 % of the total oil constituents. The oil composition was predominated by monoterpenes (75.33 %) both hydrocarbons (43.57 %) and oxygenated (31.76 %), with α-pinene (25.35 %), α-thujone (12.86 %), β-caryophyllene (7.54 %) and 1,8-cineole (7.23 %) as major components. This essential oil demonstrated a remarkable growth inhibitory effect on Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Candida albicans. Consequently, S. bicolor essential oil could be considered a natural alternative to traditional food preservatives and could be used to enhance food safety and shelf life. It could also be used in diseases caused by susceptible microorganisms.