Antagonistic effects of Bacillus natto and Streptococcus faecalis on growth of Candida albicans

The growth-inhibitory effects of Bacillus natto and Streptococcus faecalis on Canida albicans were investigated. When inoculated into the filtrate of a long-term culture of B. natto strain BN (BN), a stock culture of C. albicans RIMD 0301020 lost its viability completely, whereas C. albicans RIMD 0301011, a fresh isolate from a clinical source, did not. In continuous flow (CF) culture the growth of both strains of C. albicans was suppressed by mixed cultivation with BN. On the other hand, in classical batch culture BN did not suppress the growth of C. albicans. S. faecalis BIO-4R, a multi-drug resistant strain, was also antagonistic to C. albicans RIMD 0301011 but symbiotic with BN in CF culture. These findings suggest that BN in concert with S. faecalis BIO-4R may inhibit the growth of C. albicans in the intestinal tract.