Antimicrobial Susceptibility to Natural Substances of Campylobacter jejuni and Campylobacter coli Isolated from Italian Poultry

Campylobacter spp. isolated from poultry are a major public health concern. Antimicrobial resistance is increasing in general, which is associated with limited treatment of diseases in animal husbandry and in human as well. The use of natural substances (enterocins and phytoadditives) seems to be a promising alternative, either in the prevention or treatment of the gastrointestinal tract infections. A total 28 broiler carcasses from Italian poultry were sampled and 39 Campylobacter strains were isolated. Twenty-four isolates were identified as Campylobacter jejuni and 15 strains were identified as Campylobacter coli by polymerase chain reaction. All Campylobacter strains were determined to be resistant to nalidixic acid, ciprofloxacin, tetracycline (E-test), cefotaxim, and ampicillin using the disk diffusion method. Interestingly, the study revealed multidrug resistance of the Campylobacter strains; however, the strains were susceptible to natural substances, such as enterocins, oregano, and sage. Eighty-five percent of the Campylobacter strains were susceptible to at least one enterocins, and 77% of the strains were susceptible to enterocin (Ent) 9296, 69% were susceptible to Ent EM41, and 69% were susceptible to Ent A(P). Sage inhibited the growth of 38% of C. jejuni strains and 53% C. coli strains, whereas oregano inhibited the growth of 50% of the C. jejuni strains and up to 67% C. coli strains. Owing to the One health concept, application of enterocins and herbal extracts is a more ecological approach for preventing bacterial contamination during production and processing of poultry, which also leads to the protection of human health.