Antibacterial Mode of Action of the Essential Oil Active Compounds against and Efflux-Mediated Drug Resistance in Gram-Negative Bacteria.

Today, an alarming rise of bacterial gastroenteritis in humans resulting from consuming -tainted foods is being observed. One of the solutions for mitigating this issue may be the antibacterial activity of essential oils. In the present research, we propose to study the antibacterial activity against and other Gram-negative bacteria of essential oil and its active molecules. In addition, a few chemically synthesized molecules such as ()-methylisoeugenol, Elemicin, and eugenol were also studied. The results showed that the essential oil itself and its most active component, ()-methylisoeugenol, exhibited bactericidal effects. Similar effects were detected using purified and chemically synthesized molecules. Also, it was observed that the essential oil and its active molecules affected intracellular potassium and intracellular ATP contents in cells. Inhibition of the membrane bound FF-ATPase was also observed. Eventually, for the first time, the efflux mechanism of active molecules of essential oil was also identified in gamma proteobacteria and its specific antibacterial activity against was associated with the lack of this efflux mechanism in this species.