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

Öz

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.

Anahtar Kelimeler

• Artisanal cheese
• Antibiotic susceptibility
• Biofilm forming
• Farmers’ market

Geleneksel Peynirlerde Gıda Güvenliği Riskleri: Türkiye’nin Ereğli İlçesinde Listeria ve Salmonella Türlerinin Tespiti ve Karakterizasyonu

Öz

Bu çalışma, Konya ili Ereğli ilçesindeki çiftçi pazarlarında satılan peynirlerde Listeria ve Salmonella türlerinin varlığını, moleküler tanımlamasını, antibiyotik direncini ve biyofilm oluşturma kapasitesini araştırmak amacıyla gerçekleştirilmiştir. Toplam 120 adet peynir örneği seçici zenginleştirme besiyerleri ve izolasyon yöntemleri kullanılarak analiz edilmiştir. Numunelerin hiçbirinde Salmonella spp. varlığı tespit edilememiş ancak iki örnekte (%1,7) Listeria spp. tespit edilmiştir. Konsensüs dizileri, NCBI GenBank veri tabanına PX415425 (L33) ve PX415426 (L49) erişim numaralarıyla kaydedilmiş olup, Listeria innocua izolatlarının dünya genelindeki suşlarla %99,79–100 benzerlik gösterdiği belirlenmiştir. İki izolatın (L-49 ve L-33) 14 antibiyotiğe karşı duyarlılık testinde; ampisilin, penisilin, eritromisin ve tetrasiklin dahil olmak üzere yaygın kullanılan antibiyotiklere genel olarak duyarlı oldukları görülmüştür. Ancak, L-33 ve L-49’da sefoksitine karşı direnç, ayrıca L-49’da rifampisine karşı orta düzeyde direnç saptanmıştır. Biyofilm testleri, L-33 ve L-49’un orta düzeyde biyofilm oluşturduğunu ortaya koymuştur. Bu bulgular, geleneksel peynirlerde Listeria spp. bulunabileceğini göstermektedir. Listeria spp.’nin sınırlı antibiyotik direncine rağmen değişken biyofilm oluşturma kapasitesi, peynir üretimi ve pazarlanmasında sıkı hijyen önlemlerinin gerekliliğini vurgulamaktadır.

Anahtar Kelimeler

• Geleneksel peynir
• Antibiyotik duyarlılığı
• Biyofilm oluşturma
• Çiftçi pazarı

Kaynakça

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