The interaction between maize resistant starch III and Bifidobacterium adolescentis during in vitro fermentation

As an alternative to traditional dietary fibers with prebiotic effects, the interaction between resistant starch III (RS3) and gut microbiota is worth exploring. In this study, the effects of RS3 on the proliferation of Bifidobacterium adolescentis (B. adolescentis) and their structural changes before and after fermentation were investigated. Autoclaved-debranched resistant starch (ADRS) demonstrated the best proliferative effect for B. adolescentis and the highest roughness (Ra = 21.90 nm; Rq = 16.00 nm). The rough surface of ADRS was the key for B. adolescentis proliferation. B. adolescentis produced an extracellular amylase to assist degradation and showed the highest activity in ADRS. Fermentation disrupted short-range ordered structure and reduced R_{1047 cm^-1/1022 cm^-1} by 20.74 % and R_{995 cm^-1/1022 cm^-1} by 30.85 %. The extracellular amylase was essential substance for ADRS degradation. These findings help optimize RS3 structure and promote the proliferation of intestinal probiotics.