Chemical composition and some biological activities of the essential oils from basil Ocimum different cultivars

Background: The plants belonging to the Ocimum genus of the Lamiaceae family are considered to be a rich source of essential oils which have expressed biological activity and use in different area of human activity. There is a great variety of chemotypes within the same basil species. Essential oils from three different cultivars of basil, O. basilicum var. purpureum, O. basilicum var. thyrsiflora, and O. citriodorum Vis. were the subjects of our investigations. Methods: The oils were obtained by steam distillation in a Clevenger- type apparatus. The gas chromatography mass selective analysis was used to determine their chemical composition. The antioxidant activities of these essential oils were measured using 1,1- diphenyl- 2- picrylhydrazyl assays; the tyrosinase inhibition abilities of the given group of oils were also assessed spectophotometrically, and the antimicrobial activity of the essential oils was determined by the agar diffusion method, minimal inhibitory concentrations were expressed. Results: According to the results, the qualitative and quantitative composition of essential oils was quite different: O. basilicum var. purpureum essential oil contained 57.3% methyl- chavicol ( estragol); O. basilicum var. thyrsiflora oil had 68.0% linalool. The main constituents of O. citriodorum oil were nerol ( 23.0%) and citral ( 20.7%). The highest antioxidant activity was demonstrated by O. basilicum var. thyrsiflora essential oil. This oil has also exhibited the highest tyrosinase inhibition level, whereas the oil from O. citriodorum cultivar demonstrated the highest antimicrobial activity. Conclusions: The results obtained indicate that these essential oils have antioxidant, antibacterial and antifungal activity and can be used as natural antioxidant and antimicrobial agents in medicine, food industry and cosmetics.