Comparative analysis of the chemical composition and antimicrobal activities of some of Lamiaceae family species and Eucaliptus (Eucaliptus globules M)
The aim of this study was to evaluate and compare the antimicrobial activity of four essential oils that belong to Lamiaceae family (sage, oregano, thyme) and eucalyptus oil. Gas chromatography coupled with mass spectrometry (GC-MS) revealed that the highest percent of essential oils 98.93% include three classes of compounds - monoterpene hydrocarbons, aromatic hydrocarbons and oxidized monoterpenes. The main components are oxidized monoterpenes: carvacrol (59.03%); thymol (36.12%), eucalyptol (20.66%), hydrocarbon monoterpenes: limonene (30.96%) and α-pinene (12.21%) and aromatic monoterpene, p-cymene (22.25%) All essential oils showed great potential of antimicrobial activity against several bacteria and yeast C. albicans, using the agar diffusion method with wells. Minimum inhibitory concentration (MIC) for the essential oils has been determined by the broth dilution method and valued in the range from 1 to 5 μL/m, depending on the essential oil and bacteria tested, and up to 100 μL/ml for C. albicans. The essential oils of Lamiaceae family exhibited a strong antibacterial activity for tested microorganisms, while the essential oils of thyme were especially recognized.