Bacteriocin Production Of Enterococcus Species Isolated From Milk And Some Cheese Samples

Document Type : Original Article


1 Dairy Department, Faculty of Agriculture, Al Azhar University, Cairo, Egypt

2 2Dairy Department, Faculty of Agriculture, Mansoura University, Egypt

3 Dairy Department, Faculty of Agriculture, Al Azhar University, Cairo, Egypt.

4 Food Science and Technology Department, Faculty of Agriculture, Al-Azhar University

5 Food science and technology Department, Faculty of Agriculture, Al-Azhar university, Cairo, Egypt

6 chemistry of flavour and aroma department, food science and nutrition division,

7 El-Behoose St. Dokki Giza Egypt


Enterococci can be used as a starter or probiotic culture in the food industry. However, enterococci are also implicated in severe multi-resistant nosocomial infections. In this study, some probiotic characteristics such as antimicrobial activity and antibiotic susceptibility were investigated.Twenty-three strains of Enterococcus species isolated from Raw milk (7 strains), Karish cheese (8 strains), Domiati cheese (5 strains), and Ras cheese (3 strains) were studied for the capability to produce bacteriocin and antibiotic susceptibility.The seven studied antibiotics showed a different powerful effect on Enterococcus strains. The most effective antibiotic against 23 Enterococcus strains were amikacin, cefotaxime, and cefoxitin, which inhibited the growth of all tested strains, followed by levofloxacin azlocillin, and cloxacillin which inhibited 21, 19, and 19 strains, respectively, out of 23 studied strains. In addition, colistin showed the lowest powerful effect against all Enterococcus strains studied was resistant to this antibiotic. Antimicrobial activity was confirmed for all 23 strains against B. thuringiensis and 16, 13, 9, 9, 7, 6 out of 23 strains against Str. pyogenes, Ps. aeruginosa, B. cereus, Staph. aureus, E. coli O157:H7, and S. typhimurium, respectively. Strains E. faecium Rm5-1, E. faeciumRm6-1, E. durans Rm3-1, E. durans Rm3-2, E. durans Kc1-1, E. durans Kc5-2, E. faecalis Kc2-1, E. faecium Dc1-1, E. faeciumDc10-2, and E. durans Rc3-2 showed potent antimicrobial activity against most indicator strains.


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