Evaluation of pathogenicity indicators and technological properties of Enterococcus faecium isolates obtained from traditional Iranian cheeses

Recently, special attention has been paid to enterococci for use as probiotics in dairy products. All these desirable features are a stimulus for the producers of dairy products to use enterococci isolated from dairy products such as Liqvan cheese. Despite having all these features, enterococci are not recognized as GRAS and their presence in food products is a sign of fecal contamination. The purpose of this research is to investigate enterococci isolated from Liqvan and Koze cheese in terms of having pathogenic indicators in order to confirm that they are safe for consumers and finally to investigate the possibility of using them as starters or starter aids in dairy products. Especially cheeses. Based on this, 57 isolates of Enterococcus faecium from traditional Iranian cheeses were examined for the presence of pathogenic genes, and finally 23 isolates did not have any pathogenic genes. Then the technological properties of these isolates such as acidification, proteolytic, lipolytic, autolytic, heat and acid resistance and exopolysaccharide production were investigated. The results showed that among the 23 investigated strains, 19 isolates had antimicrobial activity against pathogenic bacteria, 16 strains were able to produce exopolysaccharide and 20 isolates had moderate acidification properties. The highest proteolytic and lipolytic activity was related to strains c18 and c16, respectively, and strain LR78 showed the highest acid and heat resistance.