AUTHOR=Guo Ling , Sun Qi , Gong Shaoying , Bi Xue , Jiang Wen , Xue Wei , Fei Peng 

TITLE=Antimicrobial Activity and Action Approach of the Olive Oil Polyphenol Extract Against Listeria monocytogenes

JOURNAL=Frontiers in Microbiology

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2019.01586

DOI=10.3389/fmicb.2019.01586

ISSN=1664-302X

ABSTRACT=<p>Olive oil polyphenol extract (OOPE) has been reported to have antibacterial activity; however, its effect on <italic>Listeria monocytogenes</italic> is less studied so far. This study, thus, aimed to reveal its antimicrobial activity and action approach against <italic>L. monocytogenes via</italic> evaluating the minimum inhibitory concentration (MIC) as well as the changes of intracellular adenosine 5′-triphosphate (ATP) concentration, cell membrane potential, bacterial protein, DNA, and cell morphology. The results showed that OOPE could inhibit the growth of <italic>L. monocytogenes</italic> with a measured MIC of 1.25 mg/ml. <italic>L. monocytogenes</italic> cells treated by OOPE showed significant reduction in intracellular ATP concentrations, bacterial protein, or DNA (<italic>p</italic> &lt; 0.05), in comparison with those without any treatment. In addition, OOPE was observed to depolarize strain cells and alter cell morphology, resulting in damaged cell membrane and, thereby, leakage of cell fluid. These findings demonstrated that OOPE had inhibition on <italic>L. monocytogenes via</italic> its action on cells, suggesting its potential as a natural preservative.</p>