Bacteriocinogenic Probiotics from Chicken Gut Mucosa as an Effective Strategy to Control Campylobacter jejuni

Abstract

Campylobacteriosis is a major global foodborne illness often associated with the consumption of poultry products, a common source of outbreaks and a risk factor for sporadic infections with this pathogen. Campylobacter jejuni accounts for 74% of the estimated human campylobacteriosis. Despite the recent ban of antibiotics in poultry as growth promoters, approximately 28% of C. jejuni isolates from chickens exhibit antibiotic resistance. Bacteriocinogenic probiotics has been proposed as a promising alternative strategy for reducing the incidence of enteric pathogens in poultry. The main objective of this study was to isolate and identify novel bacterial strains with bacteriocinogenic properties against C. jejuni from the cecal mucosa of broiler chickens and characterize their probiotic potential. Of 33 tested bacteria, 15 strains that exhibited the highest antimicrobial activity were identified as Ligilactobacillus salivarius based on 16S rRNA Sequencing. The strain L. salivarius UO.C249 showed potent antimicrobial activity against C. jejuni, as confirmed using micro-dilution assay, agar well diffusion method, and colony counting. Its cell-free supernatant (CFS) exhibited a dose-dependent anti-Campylobacter activity, likely due to the presence of bacteriocin-like moieties, as confirmed by protease treatment. Genome and proteome analyses of L. salivarius UO.C249 revealed presence of known bacteriocins, including the Abp118. The strain was sensitive to several antibiotics and had a high survival rate in the simulated chicken gastrointestinal tract.