| Summary: | This study aimed to investigate whether bacterial lysates (BLs) extracted from <i>Pediococcus acidilactici</i> reduce <i>Listeria monocytogenes</i> biofilm formation, as well as adhesion to and invasion of human intestinal epithelial cells. Pretreatment with <i>P. acidilactici</i> BLs (20, 40, and 80 μg/mL) significantly inhibited <i>L. monocytogenes</i> biofilm formation on the surface of polystyrene (<i>p</i> < 0.05). Fluorescence and scanning-electron-microscopic analyses indicated that <i>L. monocytogenes</i> biofilm comprised a much less dense layer of more-dispersed cells in the presence of <i>P. acidilactici</i> BLs. Moreover, biofilm-associated genes, such as <i>flaA</i>, <i>fliG</i>, <i>flgE</i>, <i>motB</i>, <i>degU</i>, <i>agrA</i>, and <i>prfA</i>, were significantly downregulated in the presence of <i>P. acidilactici</i> BLs (<i>p</i> < 0.05), suggesting that <i>P. acidilactici</i> BLs prevent <i>L. monocytogenes</i> biofilm development by suppressing biofilm-associated genes. Although <i>P. acidilactici</i> BLs did not dose-dependently inhibit <i>L. monocytogenes</i> adhesion to and invasion of intestinal epithelial cells, the BLs effectively inhibited adhesion and invasion at 40 and 80 μg/mL (<i>p</i> < 0.05). Supporting these findings, <i>P. acidilactici</i> BLs significantly downregulated <i>L. monocytogenes</i> transcription of genes related to adhesion and invasion, specifically <i>fbpA</i>, <i>ctaP</i>, <i>actA</i>, <i>lapB</i>, <i>ami</i>, and <i>inlA</i>. Collectively, these results suggest that <i>P. acidilactici</i> BLs have the potential to reduce health risks from <i>L. monocytogenes</i>.
|
|---|
