Antimicrobial Properties and Chemical Composition of Essential Oils Isolated from Six Medicinal Plants Grown in Romania Against Foodborne Pathogens

The aim of this study was (1) to determine the chemical composition of essential oils (EOs) from 6 medicinal plants grown in Romania: Achillea millefolium, Calendula officinalis, Hyssopus officinalis, Hypericum perforatum, Mentha piperita, and Mentha smithiana, and (ii) to determine the effectiveness of these essentials oils tested against 7 common food-related bacteria and fungus at four different dosages (5, 10, 15 and 20 mu L/disc, respectively). Gas chromatography-mass spectrometry analysis indicates that the EOs obtained from these Romanian medicinal plants have a great variability in their chemical composition. The study reports for the first time the antibacterial activity of the M. smithiana EO. All the essential oils screened showed antimicrobial activity, the most active being M. smithiana and M. piperita, in contrast to A. millefolium and C. officinalis. Enterococcus faecalis and Pseudomonas aeruginosa exhibited a low degree of sensitivity, while Candida albicans was the most susceptible to the action of EOs. The antimicrobial activity recorded recommends the EOs tested as a potential source of natural antiseptics against foodborne bacterial pathogens.