Isolation and identification of indigenous Lactobacilli in traditional dairy products in Iran

One hundred and twelve traditional dairy samples including yoghurt, doogh and raw milk were collected from Kermanshah, Kurdistan, Lorestan, Ilam and Markazi provinces in Iran. The bacteria were isolated based on standard procedure. The samples were sub-cultured on selective media, typical colonies were examined microscopically and finally ninety three bacteria were selected for further analyses. The isolated bacteria were characterized by fermentation of 19 sugars and growing in 15 and 45 ºC, nitrate reduction, gelatin solidification and esculin degradation. In order to confirm the biochemical results, molecular analysis such as amplification of lactobacillus genus specific fragment with specific primer was carried out. The results showed that all isolates belong to lactobacillus. Four lactobacillus with specific properties were further identified by amplification and sequencing of 16S rDNA gene. These genes were submitted to gene bank in NCBI. The phylogenetic tree was constructed after comparing with other 16S rDNA genes. Results showed that two strains were similar to Lactobacillus crustorum which was recorded recently.