Antibiotic susceptibility, antibacterial activity and characterisation of Enterococcus faecium strains isolated from breast milk


Kıvanç S. A. , Kıvanç M., Yigit T.

EXPERIMENTAL AND THERAPEUTIC MEDICINE, vol.12, no.3, pp.1732-1740, 2016 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 12 Issue: 3
  • Publication Date: 2016
  • Doi Number: 10.3892/etm.2016.3545
  • Title of Journal : EXPERIMENTAL AND THERAPEUTIC MEDICINE
  • Page Numbers: pp.1732-1740
  • Keywords: Enterococcus faecium, breast milk, probiotics, antibacterial activity, ocular surface, LACTIC-ACID BACTERIA, DAIRY-PRODUCTS, MOLECULAR CHARACTERIZATION, VIRULENCE DETERMINANTS, BIOFILM FORMATION, FAECALIS, CHEESE, INFANT, PROTEOLYSIS, FOOD

Abstract

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 of Enterococcus faecium strains 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 of E. faecium, were determined. In addition, biofilm formation by E. faecium strains was assessed. E. faecium strains 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 the E. faecium TM13, TM15, TM17 and TM18 strains were shown to be effective against Listeria monocytogenes, and were also resistant to heat. Further studies are required in order to determine whether certain strains of E. faecium may be used for the development of novel antibacterial agents.