Eurotium-Cristatum fermented black tea alleviates ulcerative colitis through the PPARγ-NF-κB signaling axis

Ulcerative colitis (UC) is a chronic inflammatory bowel condition that significantly impairs patient quality of life and remains incurable. Effective dietary management is crucial for both prevention and treatment. This study investigates the effects and mechanisms of Eurotium cristatum-fermented black tea (FBT) in a dextran sulfate sodium (DSS)-induced UC mouse model using transcriptome sequencing, immunofluorescence, and flow cytometry. Our results demonstrate that FBT significantly protects intestinal integrity by suppressing NF-κB-dependent inflammatory genes through the activation of peroxisome proliferator-activated receptor gamma (PPARγ) and modulation of the NF-κB signaling pathway. FBT enhances intestinal barrier integrity by limiting microbial penetration and metabolite translocation into systemic circulation, thereby reducing systemic inflammation risk. Additionally, FBT promotes intestinal mucosa repair and maintains microecological homeostasis by regulating intestinal flora and enhancing the biosynthesis of short-chain fatty acids and amino acids. These findings suggest that FBT has promising prophylactic potential for preventing and alleviating UC by modulating multiple biological pathways, including reducing inflammation, mitigating oxidative stress, and strengthening intestinal barrier integrity. This study lays the groundwork for future research on dietary interventions for UC prevention and management.