The effect of riboflavin on the growth of bifidobacterium adolescentis and bacillus cereus / 中国药理学通报

ABSTRACT

AIM To investigate the potential effect of riboflavin on the growth of probiotic strains Bifidobacterium adolescentis ( B. adolescentis) and Bacillus cereus ( B. cereus) . METHODS By means of routine bacterial quantitative culture, Gram's staining, and light microscopy, changes in B. adolescentis and B. cereus counts were detected in the presence of riboflavin at different concentrations (1, 0 5, 0 25, 0 g?L -1 ). RESULTS ①The counts of B. adolescentis increased by 10 to 100 fold in 1g?L -1 riboflavin group after 48 h, and 10 to 390 fold in 0 5 g?L -1 and 0 25 g?L -1 riboflavin groups within 72 h as compared to that without riboflavin supplement. Meanwhile, the chain lengths of B. adolescentis were markedly longer in culture system with riboflavin than those without. ②Compared with 0 g?L -1 riboflavin group, the count of B. cereus increased significantly in 0 5 g?L -1 riboflavin group at 36 h, and in 0 25 g?L -1 riboflavin group within 72 h, while it decreased by 50 to 100 000 fold in 1 g?L -1 riboflavin group within 72 h. Likewise, the chain length of B. cereus was markedly longer in 0 5 g?L -1 and 0 25 g?L -1 riboflavin groups, together with the delayed spore formation of B. cereus. ③The 6 month survival rates of B. adolescentis and B. cereus counts in preparations (depositing at 4℃) with 0 5 g?L -1 riboflavin were much higher than those without riboflavin supplement. CONCLUSION Riboflavin in concentrations of 0 5 g?L -1 and 0 25 g?L -1 could markedly enhance the growth of B. adolescentis and B. cereus. 0 5 g?L -1 riboflavin might be beneficial to improve the survival rate of B. adolescentis as well as B. cereus when storing for a long term.