ARDRA Analysis on Biodiversity of Lactobacilli Isolated from Bulgarian Raw Buffalo Milk

Lactic acid bacteria are widespread in nature and occur naturally as indigenous microflora in raw milk. Considering that buffalo milk is an excellent medium for the growth of a large variety of lactic acid bacteria, the aim of this study was the isolation of Lactobacillus spp. strains from raw buffalo milk orig¬inating from different areas and their species identification, using Amplified Ribosomal DNA Restriction Analysis (ARDRA) and a set of five reference strains of the most frequently isolated Lactobacillus species. From the analysis of the patterns generated after treatment with HaeIII it was found that 24 (88.8%) of the isolates had profiles that matched the reference 16S rDNA of Lactobacillus casei. The restriction profiles of the remaining three isolates (12.2%) did not match any of the reference strains and they were identified by API 50 CHL as Lactobacillus fermentum. This indicates that L. casei is highly adaptive and dominates in raw buffalo milk regardless of the climatic conditions and the method of raising animals.