Effect of prebiotic supplementation on the low-temperature storage stability and in vitro gastrointestinal tolerance of Bifidobacterium breve and Bifidobacterium longum in lactose and sucrose systems

The objective of this study was to investigate the effect of fructooligosaccharides (FOS) and inulin supplementation on the stability of Bifidobacterium breve and Bifidobacterium longum grown in lactose and sucrose systems over 12-week low-temperature storage at 4 °C. FOS and inulin supplementation in the lactose and sucrose systems improved the low-temperature storage stability of B. breve and B. longum. On week 12, the highest lactic (29.7 ± 0.7%) and acetic acid (28.7 ± 1.3%) concentrations were observed in B. breve in 2% lactose with 3% inulin supplementation. In week 12, B. breve auto-aggregation rate and hydrophobicity significantly increased in 2% lactose with 3% inulin supplementation than non-supplemented (2% lactose). At week 0, the co-aggregation of B. longum and B. breve with E. faecalis and E. coli significantly increased compared to non-supplemented media. However, as the storage week proceeded, the co-aggregation ability of B. longum and B. breve drastically declined. FOS and inulin supplementation in these sugar systems significantly improved hydrophobicity, auto-aggregation, and co-aggregation ability with Enterococcus faecalis and Escherichia coli compared to non-supplemented media. In addition, the increase in the bacterial survival rate in vitro gastrointestinal tolerance assay showed that FOS and inulin supplementation in these sugar systems improved the gastric-intestinal tolerance of B. breve and B. longum.