Biochemical and molecular identification of Entrococcus isolated from traditional fermented milk and assessment of their antimicrobial activity against some pathogens [electronic resource]

Includes bibliographic reference

The purpose of the present work was to characterize promising starter culture strains of Enterococcus faecium and Enterococcus durans isolated from traditional fermented mille The antimicrobial activity of E. faecium and E. durans against Staphylococcus aureus (MRSA), Pasteurella multocida and Pseudomonas fluorescens was evaluated. A total of 20 isolates of lactic acid bacteria were characterized using morphological characters and all the isolates were Gram-positive and catalase-negative lactic acid bacteria. Eight isolates were identified as Enterococcus spp using API kit and confirmed by using Enterococcus genus-specific primers (Sod A). Based on 16SrRNAgene analysis, four isolates were identified as E. faecium and four isolates were identified as E. durans. The plasmid contents and profiles of the strains were showed, all tested strains carried a certain number of plasmids ranged from 2 to 8 with different molecular sizes. The effectiveness of the antimicrobial activity of Enetrococcus is strictly related to the species and strain of the target microorganism. Commercial kits for species identification of E. durans and E. faecium are in some cases incorrect to distinguish species of enterococci, so the molecular identification of Enterococcus strain play an important role in food industry as starter cultures to improve food quality and safety.

Summary in Arabic