Population structure and safety aspects of Enterococcus strains isolated from artisanal dry fermented sausages produced in Argentina


Graciela Vignolo, Centro de Referencia para Lactobacilos (CERELA), CONICET, Chacabuco 145, (T4000ILC) San Miguel de Tucumán, Tucumán, Argentina.
E-mail: vignolo@cerela.org.ar


Enterococci population from Argentinean artisanal dry fermented sausage was identified and their safety aspects were evaluated. Species-specific PCR was used to distinguish between Enterococcus faecium (56%) and Enterococcus faecalis (17%). Other isolates (27%) were identified as Enterococcus durans, Enterococcus casseliflavus and Enterococcus mundtii by using 16S RNA gene sequence. RAPD analyses showed different biotypes for Ent. faecium and Ent. faecalis species. Low incidence of antibiotic resistance and high virulence traits in Ent. casseliflavus and Ent. faecalis were found; the majority of the Ent. faecium strains were shown to be free of virulence factors. The absence of virulence/resistance traits and the anti-Listeria activity of Ent. faecium isolates may be exploited to enhance natural preservation thereby guaranteeing organoleptic/safety characteristics of artisanal fermented sausages.