Propionylated high-amylose maize starch alleviates obesity by modulating gut microbiota in high-fat diet-fed mice

[Display omitted] •PS showed anti-obesity effects on HFD-fed mice and regulated metabolic disorders.•The content of propionate showed an increasing trend in mice supplemented with PS.•Mice in the PS group exhibited an altered gut microbiota.•Increased S24-7 and Ruminococcus are associated with weight-reducing effects. Obesity threatens human health worldwide, and mounting findings have found that gut microbiota (GM) changes induced by diet intervention influence its development. This study aims to investigate the anti-obesity effects and GM changes of propionylated high-amylose maize starch (PS) in C57BL/6J mice fed with high-fat diet (HFD). In our results, PS decreased the body weight of HFD-fed mice after 8 weeks and regulated the glucose stability and insulin resistance. High-amylose maize starch (HAMS) and PS regulated the serum lipid levels and inflammatory response. Moreover, PS yielded more propionate relative to HAMS, proving that introduced propionyl groups could be released in the colon. 16S rRNA results showed that PS altered GM with the increase of bacteria (S24-7 and Ruminococcus) and decrease of harmful genera, which is linked to the anti-obesity effect. Our results provide a reference for the design of functional dietary fibers inducing high propionate production and GM modulation.