The search for new antimicrobial agents is a field of utmost importance since the prevalence of antimicrobial resistance among key microbial pathogens is increasing at an alarming rate worldwide. This study was performed in order to isolate and identify the potential Enterococci strains exhibiting anti-microbial activity with the help of two anti-microbial detection methods namely Agar-Spot and Well-Diffusion Assay. A collection of Enterococci spp. (about 96 isolates) were isolated from two Iranian raw milk cheeses, namely Lighvan and Koozeh, and subsequently, identified as Enterococcus faecium, Enterococcus faecalis, Enterococcus durans, Enterococcus casseliflavus and Enterococcus italicus by 16S rDNA sequencing. All of the 96 isolates were subjected to Agar-Spot and Well-Diffusion Assay in order to detect their ability to produce antimicrobial compounds. According to Agar-Spot method, 48 out of the 96 isolates produced clear zone on the plates against indicator organisms. With Well-Diffusion Assay, the positive isolates with clear zone decreased to 20 isolates. These 20 isolates (strains) were then subjected to rep-PCR for typing, and 15 distinct rep-PCR profiles (patterns) were identified, from these 15 positive strains, 11 strains were found to belong to Enterococcus faecium.

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