(P19-005-25) Designed Prebiotic Fiber Mixtures for Superior Gut Microbiota and Whole-Body Health

Objectives: Dietary fiber interventions to modulate the gut microbiota often rely on isolated fibers, overlooking potential synergistic effects of fiber combinations. We hypothesized that mechanistically blended fibers could promote health-associated microbial taxa more effectively than single fibers. This study aimed to design and evaluate dietary fiber mixtures that support complementary microbial groups related to health and compare their effects to individual fiber components.

Methods: Fiber mixtures were developed through pooled in vitro fecal fermentations to optimize support for diverse bacterial groups linked to gut health. The mixtures and their individual fiber components were then tested in vitro using fecal samples from 10 healthy adults. Microbial community structure, alpha diversity, and short-chain fatty acid (SCFA) production were analyzed to compare the microbial responses to individual fibers and fiber mixtures.

Results: Fiber mixtures outperformed individual fibers in promoting beneficial bacterial taxa consistently across donors. Moreover, these mixtures led to superior alpha diversity and produced significantly higher levels of short-chain fatty acids (SCFAs) compared to what would be expected if the effects of individual fibers were merely additive when combined in a blend. Unique shifts in microbial community structure and specific taxa were observed with fiber mixtures, which were absent when individual fibers were tested, highlighting a synergistic interaction. The responses to fiber mixtures, unlike those to single fibers, were consistent across donors, particularly in promoting butyrate-producing taxa from the Clostridium cluster XIVa.

Conclusions: This study is the first to demonstrate the synergistic effects of designed dietary fiber mixtures in supporting beneficial microbes and boosting short chain fatty acid production. These findings suggest that harnessing the synergistic potential of designed fiber combinations may be a more effective strategy for future prebiotic development.

Funding Sources: No funding sources are related to this work