Food phytochemicals act as Quorum Sensing inhibitors reducing production and/or degrading autoinducers of Yersinia enterocolitica and Erwinia carotovora

Bacteria use Quorum Sensing (QS) systems to monitor their population density and to control a variety of physiological processes. In this study, the capacity of eleven phenolic compounds to inhibit QS signals in a biosensor strain (Chromobacterium violaceum) and two pathogenic bacteria (Yersinia enterocolitica and Erwinia carotovora) was evaluated. All the tested compounds inhibited QS regulated phenotypes in the biosensor strain. The identification and quantification of N-acyl-homoserine lactones (AHLs) by LC–MS/MS spectrometry showed that cinnamaldehyde, ellagic acid, pomegranate extract, resveratrol and rutin, at concentrations below their minimum inhibitory concentration, were able to reduce concentration of AHLs of both Y. enterocolitica and E. carotovora.