Different effects of soybean protein and its derived peptides on the growth and metabolism of

Bifidobacterium is a common probiotic that plays a vital role in the intestinal tract. This study aimed to explore the different effects of soybean protein and soybean peptides on the growth and metabolism of Bifidobacterium animalis subsp. animalis JCM 1190. Soybean protein and soybean peptides were digested in vitro, after which different nitrogen source containing media were prepared and used for the monoculture of Bifidobacterium animalis subsp. animalis JCM 1190 and the co-culture of Bifidobacterium animalis subsp. animalis JCM 1190 and Escherichia coli JCM 1649. During the culture process, the viable cell number and lactic acid and acetic acid contents were measured, while non-targeted metabonomics was used to detect the differential metabolites and metabolic pathways. The results showed that soybean protein and soybean peptides promoted the growth and metabolism of Bifidobacterium animalis subsp. animalis JCM 1190, while digested soybean peptides had a better effect. Digested soybean peptides increased the viable cell number and lactic acid and acetic acid contents in the monoculture by regulating glycine, serine, and threonine metabolism, as well as pyruvate metabolism, the TCA cycle, glycolipid metabolism, and other metabolic pathways, balanced the ability of Bifidobacterium animalis subsp. animalis JCM 1190 and Escherichia coli JCM 1649 to utilize nitrogen sources during the early period and enhanced the competitiveness of Bifidobacterium animalis subsp. animalis JCM 1190 during the later period in co-culture.