| Summary: | A selection of 36 commercial probiotic fermented dairy products from UK and Europe markets were evaluated for the numbers, types, and viability of <i>Lactobacillus</i> strains against the stated information on their packages. A comparative study was carried out on selectivity of MRS-Clindamycin, MRS-Sorbitol, and MRS-IM Maltose, to select the right medium for enumeration of probiotic <i>Lactobacillus</i>. Based on selectivity of medium for recovery of the targeted lactobacilli, and also simplicity of preparation, MRS-Clindamycin was chosen as the best medium for enumeration of probiotic <i>Lactobacillus</i> in fermented milks. The results of enumeration of lactobacilli showed that 22 out of a total 36 tested products contained more than 10<sup>6</sup> colony-forming units/g at the end of their shelf life, which comply with the recommended minimum therapeutic level for probiotics. Rep-PCR using primer GTG-5 was applied for initial discrimination of isolated strains, and isolates, which presented different band profile, were placed in different groups. The isolated <i>Lactobacillus</i> spp. were identified mainly as <i>Lactobacillus acidophilus</i>, <i>Lactobacillus casei,</i> and <i>Lactobacillus paracasei</i> by analysis of partial sequences of the 16S ribosomal RNA and <i>rpoA</i> genes.
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