In this study, four strains of foodborne bacteria Escherichia coli ATCC 25922, Salmonella enteritidis ATCC 13076, Bacillus subtilis ATCC 6633 and Staphylococcus aureus ATCC 25923 were examined for sensitivity to eight different chemotypes of basil - Ocimum basilicum L. (T1 -T7). These chemotypes are distinguished by their qualitative and quantitative properties. The test organisms were selected on the basis of their significance as food spoilage.
The essential oils were extracted from leaves and flowers of basil by hydrodistillation with Clevenger apparatus.
Different concentrations of these essential oils were prepared by dissolving the oils with ethanol (1:1 and 2:1). Antimicrobial effects of these oils were examined on tested bacteria by using disk method.
All the oils tested displayed some antimicrobial activities. However, the efficiency differed and depended both on the chemotype of basil and concentration of the oil, as well as the examined microbial strain. Some essential oils at lower dilutions were microbiostatic, whereas highest doses proved microbicidal effect. The most sensitive bacteria was E. coli, the most resistant bacteria were S. aureus and S. enteritidis. The highest activity was demonstrated by essential oils of chemotype T7 of basil.
Key words: essential oils, Ocimum basilicum, foodborne pathogens.