Prevalence, acquired antibiotic resistance and bacteriocin production of Enterococcus spp. isolated from tunisian fermented food products

Abstract

In this study, a total of 100 fermented food products including dairy (Lben, Rayeb, Rigouta, and Jben) olive and vegetable products, harvested in Northwestern Tunisia, were investigated for the presence of Enterococcus spp. Our results showed high levels of contamination with Enterococcus spp., identified according to standard bacteriological, biochemical and phenotypic criteria. 143 isolates were recovered; E. faecium (46.15%) was the predominant species, followed by E. faecalis (27.27%), E. casseliflavus (12.58%), E. durans (8.39%) and E. mundtii (5.59%). None of the isolates showed acquired resistance againts clinically relevant drugs used for enterococcal infections treatment in human medicins, and no haemolytic activity was demonstrated. Furthermore, over 50% of the isolates within each species exhibited antilisterial bacteriocin production. Further data are needed to enhance understanding of bacteriocin production of enterococci in fermented food products as well as the potential risks to quality and safety, including possible transmission of antibiotic resistant organisms to human consumers.