Chemical composition and antibacterial activity of spice essential oils against Escherichia coli and Salmonella Typhimurium

The aim of the present study was to investigate the chemical composition of spice EOs from the family of Lamiaceae (basil, mentha, winter savory) and Apiaceae (dill) as well as their antibacterial activity against food-borne pathogenic bacteria Escherichia coli (E. coli) and Salmonella Typhimurium (S. Typhimurium). Chemical composition of the EOs was identified by gas chromatography coupled with mass spectrometer detector (GC-MS). The results showed that linalool (in basil EO), menthol (in mentha EO), p-cymene (in winter savory EO) and carvone (in dill EO) were the main compounds. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were also determined by broth microdilution method. All EOs possessed significant antibacterial effects on both tested bacterial strains. Dill EO had the highest antibacterial activity against tested bacterial strains with MIC/MBC values of 3.55 mu L/mL, while mentha had the lowest antibacterial activity with MIC/MBC values of 14.20 mu L/mL against E. coli and 56.81 mu L/mL against S. Typhimurium. The MIC/MBC values of basil and winter savory EOs were 7.10 mu L/mL for both tested bacteria. Based on the present study, the EOs from spice herbs possess antimicrobial activity against tested food-borne pathogens and thus can be a good source of natural antimicrobials agents