Inhibitory potential of some selected essential oils and their main components on the growth and quorum-sensing based pigment production of Serratia marcescens

"In this study the antibacterial potential of ten essential oils (EOs) and their main compounds against the development and quorum sensing (QS) mechanisms of the opportunistic bacterium Serratia marcescens was determined. The growth and QS inhibitory effect was evaluated by paper disc diffusion assay. The effect of EOs and components on QS-regulated prodigiosin biosynthesis was also studied. The results of our study indicated that some of the investigated EOs influenced the development and the QS-based activity of S. marcescens. Oregano and thyme oils showed the most pronounced antibacterial effect and had the strongest anti-QS potential. From the main oil compounds the phenolics, eugenol, carvacrol and thymol, proved to be efficient growth inhibitors. While eugenol and carvacrol had also a strong negative influence on AHL-mediated QS-systems in low concentrations, thymol was not effective in QS inhibition. Keywords: essential oils, quorum-sensing, prodigiosin."