title: Inhibition of quorum-sensing signals by essential oils.
abstract: The role of quorum sensing (QS) is well known in microbial pathogenicity and antibiotic resistance. QS is responsible for motility, swarming, and biofilm production based on the signal molecules, e.g., acylated homoserine lactones (AHLs) produced by micro-organisms above certain population density. The inhibition of QS may reduce pathogenicity, antibiotic resistance and biofilm formation in systemic and local infections. The homoserine lactones and other transmitters contribute to antibiotic resistance and pathogenicity of several bacteria; consequently the inhibition of QS signals reduces the problem of resistance and virulence. Due to the increasing number of persistent non-treatable infections, there is an urgent need to develop new strategies to combat infections that destabilize bacterial communities in the host. The effect of essential oils on bacterial growth and QS were evaluated using the sensor strain Chromobacterium violaceum CV026 and N-acyl homoserine lactone (AHL) producing Escherichia coli ATTC 31298 and the grapevine colonizing Ezf 10-17 strains. Of the tested oils, rose, geranium, lavender and rosemary oils were the most potent QS inhibitors. Eucalyptus and citrus oils moderately reduced pigment production by CV026, whereas the chamomile, orange and juniper oils were ineffective.
authors.affiliation: Department of Medical Microbiology, Faculty of Pharmacy, University of Szeged, Szeged, Hungary.
authors.forename: Mira Agnes
authors.initials: MA
authors.lastname: Szabó
authors.forename: Gábor Zoltán
authors.initials: GZ
authors.lastname: Varga
authors.forename: Judit
authors.initials: J
authors.lastname: Hohmann
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Schelz
authors.forename: Erno
authors.initials: E
authors.lastname: Szegedi
authors.forename: Leonard
authors.initials: L
authors.lastname: Amaral
authors.forename: József
authors.initials: J
authors.lastname: Molnár
mesh_terms: D054742:Acyl-Butyrolactones / Q000378:metabolism; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002861:Chromobacterium / Q000187:drug effects / Q000254:growth & development; D004926:Escherichia coli / Q000187:drug effects / Q000254:growth & development; D019684:Magnoliopsida / Q000737:chemistry; D009822:Oils, Volatile / Q000494:pharmacology*; D010938:Plant Oils / Q000494:pharmacology*; D053038:Quorum Sensing / Q000187:drug effects*; D027542:Rosmarinus
chemical_list: D054742:Acyl-Butyrolactones; D000900:Anti-Bacterial Agents; D009822:Oils, Volatile; D010938:Plant Oils; C053775:rosemary oil