*2.7. Antibacterial Activity*

The antibacterial activity of PEP against foodborne bacteria was evaluated following the procedure described by Silvan et al. [22]. Briefly, 1 mL of PEP (1 mg/mL final concentrations) was transferred into different flasks containing 4 mL of BB. Bacterial inoculum (50 <sup>μ</sup>L of ~1 <sup>×</sup> 10<sup>8</sup> CFU/mL) was then inoculated into the flasks under aseptic conditions. The culture was prepared in triplicate and incubated under stirring (150 rpm) during 24 h at 37 ◦C. Growth controls were prepared by transferring 1 mL of sterile water to 4 mL of BB and 50 μL of bacterial inoculum. After incubation, serial decimal dilutions of mixtures were prepared in saline solution (0.9% NaCl) and they were plated (20 μL) onto fresh MHB agar and incubated as previously described. The number of CFU was assessed after incubation. The results of antibacterial activity were expressed as percentage of growth inhibition for the foodborne bacteria respect to the controls of bacteria growth.
