Bifidobacterium bifidum is a bacterial species exclusively found in the human intestinal tract. This species is becoming
increasingly popular as a probiotic organism added to lyophilized products. In this study, porcine
mucin was used as the sole carbon source for the selective enumeration of B. bifidum in probiotic food additives.
Thirty-six bifidobacterial strains were cultivated in broth with mucin. Only 13 strains of B. bifidum utilized the
mucin to produce acids. B. bifidum was selectively enumerated in eight probiotic food supplements using agar
(MM agar) containing mupirocin (100 mg/L) and mucin (20 g/L) as the sole carbon source. MM agar was fully
selective if the B. bifidum species was presented together with Bifidobacterium animalis subsp. lactis,
Bifidobacterium breve, and Bifidobacterium longum subsp. longum species and with lactic acid bacteria (lactobacilli,
streptococci). Isolated strains of B. bifidum were identified using biochemical, PCR, MALDI-TOF procedures and
16S rRNA gene sequencing. The novel selective medium was also suitable for the isolation of B. bifidum strains
from human fecal samples.