Antimicrobial activity and antibiotic susceptibility of and spp. intended for use as starter and probiotic cultures.

Antimicrobial activity and antibiotic susceptibility were tested for 23 and three strains isolated from different ecological niches. Agar-well diffusion method was used to test the antagonistic effect (against , , and ) of acid and neutralized (pH 5.5) lyophilized concentrated supernatants (cell-free supernatant; CFS) and whey (cell-free whey fractions; CFW) from de Man-Rogosa-Sharpe/trypticase-phytone-yeast broth and skim milk.