The dynamics of vitamin B12 synthesis by some strains of propionic fermentation bacteria

Propionic bacteria are acknowledged as the most efficient organisms in terms of vitamin B-12 production. This study aimed at determining the capability of the selected bacterial strains of propionic fermentation for vitamin B-12 biosynthesis and at evaluating the possibility of strain co-operation in a mixed culture. The strains were multiplied on a whey medium. Significant changes in the content of vitamin B-12 were observed in the early phase of logarithmic growth up to 72 h of incubation, in all cultures examined. The dynamics of synthesis and the amount of vitamin produced were found to be diversified, depending on the strain type. The results obtained indicate the possibility of applying whey as a raw material for vitamin B-12 production.