Homemade traditional cheeses for the isolation of probiotic Enterococcus faecium strains

LUCILA SAAVEDRA; MARIA PIA TARANTO; FERNANDO SESMA; FONT DE VALDEZ, GRACIELA

INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY

Elsevier

Año: 2004 vol. 81 p. 241 - 245

0168-1605

One hundred and twenty two strains of Enterococcus faecium isolated from Tafí Cheese, a homemade traditional cheese of the highlands in the province of Tucumán, Argentina, were evaluated for their potential application as starter cultures in the manufacture of this traditional cheese. Eleven of the 122 strains showing limited delays in growth in oxgall were selected for the study of: bile salts hydrolase activity (BSH), cholesterol reduction, bacteriocin production, and virulence determinants. Nine strains were able to remove cholesterol in in vitro assays, a property that was closely related to the bile salt hydrolase activity. Only two strains produced active bacteriocins against Listeria strains although genetic evidence for the bacteriocin structural gene was found in six other enterococci strains. No virulence factors were detected in any of the eleven selected strains of enterococci.