Supplementation with a cranberry extract favour the establishment of butyrogenic guilds in the human fermentation SHIME system
Proanthocyanidins (PAC) and oligosaccharides from cranberry exhibit multiple bioactive health properties and persist intact in the colon post-ingestion. Yet, their bidirectional interaction with the microbiome, and the nuanced influence of a complex PAC/oligosaccharides extract on gut microbiota, dependent on time and gut region, remain inadequately characterized. This study investigates the dynamic impact of cranberry extract on gut microbiota ecology and function in six healthy participants over a two-week supplementation period using the ex vivo artificial fermentation system TWIN-M-SHIME to replicate luminal and mucosal niches of the ascending and transverse colon. Our findings revealed a significant influence of cranberry extract supplementation on the gut microbiota ecology under ex vivo conditions, resulting in a substantial alteration of bacterial metabolism. Specifically, Bifidobacterium adolescentis flourished in the mucus of the ascending colon, accompanied by a reduced adhesion of Proteobacteria. The overall bacterial metabolism shifted from acetate to propionate and, notably, butyrate production following PAC supplementation. Despite observing differences in the microbiota modulation between the six donors, this butyrogenic effect prompted by the supplementation was consistent amongst all of them. This metabolic shift was associated with the increased relative abundance of several short-chain fatty acid (SCFA) bacterial genera producer and the formation of a consortium of key butyrogenic bacteria in the mucus of the transverse colon. These observations suggest that supplementing with cranberry extract has the potential to modulate the gut microbiota in a manner that may promote overall gut health.