Isolation, identification and molecular chracterization of lactic acid bacteria from different regions of Turkey white cheese samples

Lactic acid bacteria (LAB) are highly valuable microorganisms that produce lactic acid, one of the main fermentation products of carbohydrate metabolism. LAB are commonly found in food-rich environments, particularly in dairy products, meat and vegetables. With this knowledge in our thesis work, isolation, identification and molecular characterization of lactic acid bacteria were carried out by collecting various samples of white cheese from many different localities, especially Erzurum. Eventually, 42 bacterial isolate were obtained belonging to Lactobacillus kefiri, L. brevis, L. casei, L. paracasei, Pediococcus lolii, Prolinoborus fasciculus, Staphylococcus haemolyticus, Lysnibacillus sinduriensis, P.parvulus, L. paraplantarum, Staphylococcus hominis, L. buchneri, L. plantarum, Enterococcus faecium, Micrococcus yunnanensis, Microbacterium paraoxydans and Rothia dentocariosa. For this purpose; temperature, pH and salt concentration ranges at which the bacteria developed were firstly determined. Most of the isolated bacteria were identified to develop at 30-45ºC, 3-6 pH and 2-8% salt concentration values. The test isolates were then examined using API, 16S rRNA gene analysis and rep-PCR methods. Consequently, it has been observed that (GTG)5-PCR from genomic fingerprint analysis methods is more successful than BOX-PCR in discriminating strains. According to the 16S rRNA sequence analysis data; it was concluded that of MA56 strain was similar to L. buchneri at a rate of 98%, MA13 strain was similar to E. faecium at same rate and MA27 strains was similar to E. faecium at a rate of 98% and these three isolates could be new species.