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Molecular DNA markers are valuable tools for analyzing genetic variation among yeast from different populations to reveal the genetically different autochthonous strains. In this study, we employed inter-primer binding site (iPBS) retrotransposon polymorphism to assess the genetic variation and population structure of 96 Saccharomyces cerevisiae isolates from four different regions in Turkey. The nine selected iPBS primers amplified 102 reproducible and scorable bands, of which 95.10% were polymorphic with an average of 10.78 polymorphic fragments per primer. The average polymorphism information content and the resolving power were 0.26-3.58, respectively. Analysis of molecular variance (AMOVA) revealed significant (P < 0.001) genetic differences within populations (88%) and between populations (12%). The unweighted pair group mean with arithmetic (UPGMA) dendrogram grouped 96 S. cerevisiae strains into two main clusters, where the highest probability of the data elucidating the population structure was obtained at ΔK = 2. There was not an obvious genetic discrimination of the populations according to geographical regions on UPGMA, supported by principal coordinate analysis. However, the individuals of the closer provinces in each population were more likely to group together or closely. The results indicate that iPBS polymorphism is a useful tool to reveal the genetically diverse autochthonous S. cerevisiae strains that may be important for the production of sourdough or baked goods.

Bu çalışmada farklı illerden toplanan sıkma peynir örneklerinden Enterococcus cinsi bakterilerin izolasyonu, identifikasyonu ile örneklerin genel mikrobiyolojik ve kimyasal özelliklerinin tespit edilmesi amaçlanmıştır. Bu doğrultuda, 20 peynir örneğinden 84 izolat izole edilmiş olup bunların 32’si E. faecalis, 31’i E. faecium, 13’ü E. durans, 4’ü E. gallinarum, 3’ü E. casseliflavus ve 1’i de E. thailandicus olarak tanımlanmıştır. Çalışmada incelenen peynirlerin toplam aerobik mezofilik, maya ve küf, koliform, enterokok ve laktobasil sayıları ortalama sırasıyla 7.32±0.95, 4.94±0.89, 4.02±1.88, 5.86±1.38 ve 6.90±1.22 log kob/g olarak tespit edilmiştir. Kimyasal analizler sonucunda ise ortalama kuru madde, nem, protein, yağ, kuru maddede yağ, tuz, kuru maddede tuz, kül, asitlik ve pH değerleri sırasıyla %55.44±3.68, %44.56±3.68, %23.51±2.26, %23.42±5.22, %41.89±5.16, %5.51±2.13, %10.06±5.98, %6.88±2.62, %0.3779±0.103 ve 5.66±0.14 olarak tespit edilmiştir. Sonuç olarak, sıkma peynirlerinin mikrobiyolojik ve kimyasal özelliklerinin geniş sınırlar içinde seyrettiği ve çiğ süt kullanılarak üretilmesinden kaynaklı enterokok mikroflorasının zengin olduğu gözlemlenmiştir.

This study aimed to evaluate the hemolytic activity and antibiotic susceptibility of enterococci isolated from Tulum cheese samples sold in Aksaray province. The isolates were identified as E. faecium (n = 30), E. faecalis (n = 25), and E. durans (n = 7) as a result of 16S rRNA gene sequencing. Three strains (E. faecalis ATC12, E. faecium ATC49, and E. faecium ATC54) exhibited ß-hemolytic activity, whereas others were non-hemolytic. Enterococci were found to have an intermediary or high resistance to nalidixic acid (%100), oxacillin (92%), and streptomycin (72.6%), respectively. E. faecalis strains had more resistant phenotypes to various clinically significant antibiotics than E. faecium and E. durans. Multi-drug resistance was found in 41.93% of the isolates. According to the results, Tulum cheese produced in Aksaray could be a potential vehicle for the transmission of antibiotic resistance via the food chain.