Food Safety Risks of Artisanal Cheeses: Detection and Characterization of Listeria and Salmonella spp. in Ereğli Province, Türkiye

This study investigated that the presence, molecular identification, antibiotic resistance, and biofilm-forming capacity of Listeria and Salmonella species in cheeses sold at farmers’ markets in Ereğli Province, Konya, Türkiye. Collectively 120 cheese samples were evaluated using selective enrichment and isolation methods. Salmonella spp. was not detected, in any samples while Listeria spp. was isolated in two cheese samples (1.7%). Consensus sequences were deposited in the NCBI GenBank under accession numbers PX415425 (L33) and PX415426 (L49), with Listeria innocua isolates showing 99.79 – 100% similarity to strains worldwide. Antibiotic susceptibility testing of the two isolates (L-49 and L-33) against 14 antibiotics showed overall sensitivity to commonly used drugs, including ampicillin, penicillin, erythromycin, and tetracycline. Resistance to cefoxitin was observed in L-33 and L-49, while L-49 also exhibited intermediate resistance to rifampicin. Biofilm assays revealed moderate biofilm formation in L-33 and L-49. These findings highlight that artisanal cheeses may harbor Listeria spp. Limited antimicrobial resistance, but variable biofilm-forming ability emphasize the need for strict hygiene measures in cheese production and marketing.