Antibiotic susceptibility, antibacterial activity and characterisation ofEnterococcus faeciumstrains isolated from breast milk.
Enterococci, which have useful biotechnological applications, produce bacteriocins, including those that exert anti-Listerial activity. The present study aimed to determine the antibiotic susceptibility patterns and antimicrobial activity ofEnterococcus faeciumstrains isolated from human breast milk. The strains were identified using carbohydrate fermentation tests and ribotyping. Subsequently, the antibacterial activity of the isolates was investigated, and the quantities of lactic acid and hydrogen peroxide produced, and the proteolytic activity ofE. faecium, were determined. In addition, biofilm formation byE. faeciumstrains was assessed.E. faeciumstrains exhibited antimicrobial activity against food-borne and clinical bacterial isolates. Furthermore, following 24 h incubation, the tested strains exhibited resistance to a pH range of 2.0-9.5 and tolerance of bile acid, lysozyme activity and phenol. Supernatants of theE. faeciumTM13, TM15, TM17 and TM18 strains were shown to be effective againstListeria monocytogenes, and were also resistant to heat. Further studies are required in order to determine whether certain strains ofE. faeciummay be used for the development of novel antibacterial agents.
Department of Ophthalmology, School of Medicine, Uludağ University, Görükle, 16059 Bursa, Turkey.
Sertaç Argun
SA
Kıvanç
Department of Microbiology, Faculty of Science, Anadolu University, Eskişehir 26470, Turkey.
Merih
M
Kıvanç
Institute of Science, Anadolu University, Eskişehir 26470, Turkey.
Tülay
T
Yiğit
Enterococcus faecium; antibacterial activity; breast milk; ocular surface; probiotics