beta-Glucans derived from yeast are recognized as beneficial food additives. This study evaluated crude beta-glucan extracts from Pichia kudriavzevii DPUL-51-6Y, Kluyveromyces marxianus DPUL-F15, and Saccharomyces cerevisiae DPUL-C6 strains for their anticolitis potential. Chemical analysis revealed that beta-glucan was the primary component (71.88-78.47% purity). Notably, the S. cerevisiae extract displayed superior thermal stability and hydration capacity. In RAW264.7 macrophages, beta-glucan pretreatment at 100 mug/mL significantly reduced LPS-induced nitric oxide production and pro-inflammatory cytokines by suppressing NF-kappaB signaling through the reduction of p65 and IkappaB-alpha while simultaneously activating the Nrf2 and AHR pathways. In DSS-induced colitis BALB/c mice, oral administration of crude beta-glucans alleviated intestinal damage by enhancing tight junction protein expression and restoring gut microbiota composition, characterized by an increased abundance of Lactobacillus and Prevotella. These effects were correlated with the increased production of microbial metabolites, including indole-3-lactic acid, indole-3-beta-acrylic acid, tryptophol, and short-chain fatty acids (acetic, propionic, and butyric acids). Mechanistically, beta-glucan mitigated colitis through the dual activation of Nrf2/AHR pathways and the inhibition of NF-kappaB. This study suggests that yeast-derived beta-glucan plays a significant role in mitigating the inflammatory response and may alleviate ulcerative colitis by reshaping the microbial community and metabolite profiles in the host intestinal tract.