Investigation of Genetic Diversity of Lactobacilli Isolated From Cow Milk Samples by RAPD-PCR

The use of lactobacilli in the production of fermented foods has several thousand years old due to their ability to make the desired changes in the taste and texture of the food, as well as their importance in the human health. Different dairy products can be a source of new strains of Lactobacillus. Therefore, molecular identification and their genetic variation can be an effective step in identifying native lactobacilli reserves with specific functional characteristics and applying them to industrial dairy products. The purpose of this study is to isolate lactobacilli from flora in cow's milk of Narmeshir city and study their genetic diversity. For this purpose, 21 milk samples were collected from different regions of the city, and Lactobacilli wereisolated by the conventional phenotypic and biochemical methods. In order to screen and investigate the genetic diversity of isolated lactobacilli, five RAPD primers were randomly selected. After doing PCR, the analyses of genetic and phylogenetic diversity were performed using Pyelph software and phylogeny trees were drawn. Cluster analysis of molecular data was able to divide the isolates into seven distinct groups at a genetic distance of 10. K3 and K4 isolates were in group 1 and isolates K21, K13, and K11were in group 4. The remaining isolates were placed in separate groups. Since K3 and K4 isolates were from a region and K21 and K13 isolates were also collected from a region, their placement seems to be logical in a group.