Graduate Studies
Embargoed Master's Theses
First Advisor
Amanda E. Ramer-Tait
Date of this Version
8-2025
Document Type
Thesis
Citation
A thesis presented to the faculty of the Graduate College at the University of Nebraska in partial fulfillment of requirements for the degree of Master of Science
Major: Food Science and Technology
Under the supervision of Professor Amanda E. Ramer-Tait
Lincoln, Nebraska,
Abstract
Inflammatory bowel disease (IBD) is a chronic and relapsing inflammatory disorder of the gastrointestinal tract, with increasing prevalence worldwide. Dysbiosis of the gut microbiota has been implicated in the pathogenesis of IBD. Faecalibacterium duncaniae is a prominent commensal gut bacterium known for its anti-inflammatory properties and reduced abundance in IBD patients. Recent studies suggest that increasing the abundance of F. duncaniae in the gut may help alleviate disease symptoms. However, reintroducing this species or increasing its abundance in vivo remains challenging. Condensed tannins, a subclass of dietary polyphenols derived from plants, have attracted increasing interest as candidate prebiotics that may selectively promote the growth of beneficial anaerobes such as F. duncaniae in vitro. However, whether condensed tannins can facilitate the persistence of F. duncaniae in vivo and attenuate colitis remains unclear. In this study, we utilized human microbiota-associated (HMA) mice to evaluate whether dietary supplementation with condensed tannins could promote F. duncaniae persistence in vivo. We also investigated whether a synbiotic strategy combining condensed tannins and F. duncaniae could alleviate disease severity in HMA mice exposed to dextran sulfate sodium (DSS) to induce colitis. The use of HMA mice provided a unique opportunity to investigate the ecological and functional impact of dietary bioactives on human-adapted gut microbes in a controlled setting. Findings from this research highlight the complexity of host-microbe-diet interactions and emphasize the need for additional strategies to enhance the efficacy of microbiota-based therapies targeting F. duncaniae under inflammatory conditions.
Advisor: Amanda E. Ramer-Tait
Comments
Copyright 2025, Xiaohan Wu. Used by permission