The carbohydrates contained in dietary fiber comprise the major source of nutrients for the gut microbiota, and influence its community structure. The various bacteria and bacterial groups have different abilities to utilize and compete on various carbohydrates, and such an understanding of these relationships would allow for fibers as prebiotics to be used to make predicted shifts in the microbiota for improved health. In our laboratory, we do collaborative work in using bacterial isolates and model competitive systems to gain knowledge of how bacteria utilize fibers and the alignment of carbohydrate structures with strains to favor or disfavor their growth. Our research shows a high specificity of gut bacteria fiber chemical and physical structures to bacterial needs and growth patterns. In experiments using plant cell wall arabinoxylan as model carbohydrate polymers with high variability of structures, xylan-degrading Bacteroides strains were shown to have different competitive advantages to structures existing even within the same polymer. An idea of “discrete structures” favoring bacteria at the strain level was developed. On a more global level, using in vitro human fecal fermentations and animal studies, we have shown that dietary fibers can be identified, and even designed, that have butyrogenic and propiogenic outcomes that may be desirable for health. These and other findings will be put into the context of the promise of the prebiotic hypothesis for improving health conditions and how prebiotics may someday be used in a personalized way.

Bacterial metabolism of carbohydrates, dietary fiber and gut health

254th National Meeting (2017)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.