Characterisation of a cell-free supernatant obtained from cultures of Enterococcus faecalis DBFIQ E24 with antagonistic activity against bacteria, yeasts and moulds

CARDOSO, MARÍA DE LAS MERCEDES; MANZO, RICARDO M.; TONARELLI, GEORGINA G.; SIMONETTA, ARTURO C.

INTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2012 vol. 65 p. 568 - 577

1364-727X

Enterococcus faecalis DBFIQ E24 strain produces antimicrobial substances that inhibit the growth offood-borne pathogenic bacteria, yeasts and moulds. This broad antimicrobial spectrum was determined by obtaining the cell-free supernatant (CFS) and employing the agar-well-diffusion method. Its antibacterial activity was completely inactivated by the action of proteinase K and not affected by catalase action. Besides, it was stable to thermal treatments, showing maximum antibacterial activity at pH 7.0. Moreover, CFS showed a bactericidal effect against Escherichia coli DBFIQ Ec9 strain. All these interesting physicochemical properties allow that either CFS or E. faecalis DBFIQ E24 strain to be considered as potential food biopreservatives.