Dynamics of microbial communities during inulin fermentation associated with the temporal response in SCFA production

The ecology driving the remodeling of gut microbial consortia with dietary fiber intervention remains incom-plete. We investigated the short-term dynamics of the gut microbiota and metabolic function during inulin fermentation with distinct microbiota from two swine breeds using an in vitro fermentation model. Different gut microbiota at a transient temporal time displayed a similar response to inulin intervention such as the similar fermentation stage and a rapid response followed by gradual stabilization of microbial diversity. Inulin-induced bacterial succession and individual metabolic change were determined by the original microbial compositions, in particular the alpha-diversity. Levels of short-chain fatty acids (SCFAs) were predictable with the key bacteria by the regression model, especially butyrate was associated with the abundance and ecological interactions of Lacto-bacillus delbrueckii, Bifidobacterium thermophilum and Megasphaera elsdenii. This study emphasizes the importance of complex ecology to understand fiber-induced microbiome and metabolic changes, thus providing a reference for predictable dietary responses.