Bacteriocinogenic properties and in vitro probiotic potential of enterococci from Tunisian dairy products

Arch Microbiol. 2014 May;196(5):331-44. doi: 10.1007/s00203-014-0978-y. Epub 2014 Mar 14.

Abstract

The aim of this study was to isolate new bacteriocinogenic strains with putative probiotic potential from various Tunisian fermented milks. A total of 44 Gram-positive catalase-negative isolates were colony-purified and screened for antimicrobial activity. Of inhibitory isolates, four were identified as Enterococcus durans and one as Enterococcus faecalis using 16S rRNA gene sequence. The five strains were sensitive to penicillin G, all aminoglycosides tested, to the vancomycin, tetracycline, and chloramphenicol, and E. durans 42G and E. faecalis 61B were resistant to erythromycin. The antimicrobial substances were sensitive to proteolytic enzymes and had good biochemical stability. E. durans 61A showed a good resistance to gastric and small intestinal secretions, but were more sensitive to the duodenal conditions. Considering the safety and the stability under simulated gastrointestinal tract, it appears that the bacteriocinogenic strain E. durans 61A is a good candidate for its application as novel probiotic strain in the food industry.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Bacteriocins / biosynthesis*
  • Dairy Products / microbiology*
  • Enterococcus / classification*
  • Enterococcus / drug effects
  • Enterococcus / genetics
  • Enterococcus / isolation & purification
  • Food Microbiology*
  • Gastrointestinal Tract / microbiology
  • Humans
  • Probiotics*
  • RNA, Ribosomal, 16S / genetics
  • Tunisia
  • Virulence Factors / biosynthesis

Substances

  • Anti-Bacterial Agents
  • Bacteriocins
  • RNA, Ribosomal, 16S
  • Virulence Factors