The inhibitory effect of some plant essential oils on the growth of some bacterial species

Abstract

This research is aimed at investigating the inhibitory essential oils activity of thyme, clove, cinnamon, ginger and garlic plants against some positive and negative gram pathogenic bacteria (Escherichia coli, proteus spp., Staphylococcus epidermidis, Staphylococcus aureus) by using the disk diffusion method And compares this activity with the activity of standard antibiotics, then study the synergistic and antagonistic effect between these essential oils with the antibiotics used against these bacteria. The results represented the effectiveness of all essential oils on the studied bacteria to varying degrees, except the clove oil, which doesn't show any inhibitory effect on E.coli and S.epidermidis. In contrast, cinnamon oil had the most inhibiting impact on all the bacteria studied. While garlic and ginger oil showed the lowest Inhibitory, thyme oil showed a strong inhibitory effect on E.coli and a moderate effect on other studied bacteria. Also, the results showed the synergistic effect between most essential plant oils and most antibiotics against most bacterial strains. The antagonistic effect was between essential oils with a few studied antibiotics toward some bacterial strains. Keywords: plant, essential oils, bacteria, the inhibitory effect