WGP and WGPA improved the symptoms of colitis by reducing the expression level of inflammatory cytokines in the colon; maintaining the integrity of the intestinal barrier via the upregulation of tight junction-related proteins; regulating the diversity and composition of gut microbiota; increasing the relative abundance of Ruminococcus; increasing the production of SCFAs; and inhibiting the TLR4/MyD88/NF-κB signaling pathway. The gene discussed is TLR4; the disease is colitis.