Purification and characterization of a new bacteriocin active against Campylobacter produced by Lactobacillus salivarius SMXD51

Strain SMXD51, isolated from chicken ceca and identified as Lactobacillus salivarius, produced a component that inhibits the growth of Gram-positive and Gram-negative bacteria and especially Campylobacter jejuni. The active peptide from the cell-free supernatant of Lb. salivarius SMXD51 was purified in three steps: (i) precipitation with 80% saturated ammonium sulfate, (ii) elution on a reversed phase SPE UPTI-CLEAN cartridge using different concentrations of acetonitrile, (iii) final purification by reversed phase HPLC on a C18 column. The mode of action of this peptide of 5383.2 Da was identified as bactericidal, and its amino acid composition was established. This new bacteriocin SMXD51 appears potentially very useful to reduce Campylobacter in poultry prior to processing. ► Lactobacillus salivarius SMXD51 produces a bacteriocin active against Campylobacter jejuni. ► This bacteriocin was purified to homogeneity. ► Its amino acid composition and molecular mass suggest that it is a new bacteriocin. ► Salivaricin SMXD51 inhibits food-borne pathogens (Listeria monocytogenes, Campylobacter…). ► Salivaricin SMXD51 exhibited a bactericidal and non bacteriolytic mode of action.