Studies on the anti-proliferative and anti-quorum sensing potentials of Myrtus communis L. essential oil for the improved microbial stability of salmon-based products

Abstract The purpose of this work was to evaluate the anti-proliferative and anti-quorum sensing potential of Myrtus communis L. essential oil (EO). The biopreservative attributes of EO were also determined after introduction of the oil into a chitosan-based nanomatrix. Myrtle EO concentrations ranging from 76 nl ml−1 to 500 nl ml−1 were cytotoxic against colon cancer HT-29 and liver cancer HepG2 cells. EO also inhibited the clonogenic growth of HepG2 cells. Myrtle EO doses ranging from 80 to 85 nl ml−1 did not elicit cytotoxic effects on the normal colon cells CCD 841 CoN cells but exhibited anti-quorum sensing activity against food-associated Pseudomonas fluorescens KM48 (KM48) and Pseudomonas orientalis KM149 (149). At sub-MIC levels, the EO significantly limited the production of autoinducers (i.e., AHL and PQS) and suppressed pseudomonad exopolysaccharide synthesis by 48% for KM48 and 41% for KM149. Myrtle EO at sub-MIC levels influenced the mRNA expression of exopolysaccharide genes algU (−2.5 and −1.5) and mucA (1.5 and 5.5) in KM48 and KM149, respectively. The application of the EO to the chitosan-based nanomatrix enhanced the antibacterial activity of the film against KM48 and KM149. These findings revealed the promising role of myrtle EO as a new generation antimicrobial in the food industry.