Pseudomonas aeruginosa is a potential source of food contamination that leads to food spoilage and infections as a result of the generation of biofilm and virulence factors. In the present study, we demonstrate that bacteriocin produced by Pediococcus acidilactici HW01 (HW01 bacteriocin) effectively inhibited the biofilm formation of Ps. aeruginosa (66.41, 45.77, and 21.73% of biofilm formation at 0.5, 1, and 2 mg/mL of HW01 bacteriocin, respectively) as well as the production of virulence factors. By means of a microtiter plate method and scanning electron microscopy, HW01 bacteriocin inhibited biofilm formation by Ps. aeruginosa in a dose-dependent manner. Although the viability of biofilm cells of Ps. aeruginosa was reduced in the presence of HW01 bacteriocin, the viability of planktonic cells of Ps. aeruginosa was not affected by HW01 bacteriocin (2.0 × 109 CFU/mL vs. 2.4 × 109 CFU/mL in the absence and the presence of HW01 bacteriocin, respectively). Additionally, HW01 bacteriocin decreased the twitching motility of Ps. aeruginosa as well as the production of virulence factors, such as pyocyanin, protease, and rhamnolipid. Furthermore, HW01 bacteriocin significantly inhibited Ps. aeruginosa biofilm formation on the surface of stainless steel (57% reduction at 24 h and 83% reduction at 72 h). These results indicate that HW01 bacteriocin is an effective antagonist of Ps. aeruginosa as a result of its ability to inhibit biofilm formation and the production of virulence factors.
Keywords: Bacteriocin; Biofilm; Pediococcus acidilactici; Pseudomonas aeruginosa; Virulence factor.