Purification, characterization, anti-ulcerative colitis activity of Sanghuangporus vaninii acidic polysaccharide A-3 (SVP-A-3)

Currently, Sanghuangporus vaninii, a large edible fungus of significant interest, is primarily utilized in its entirety for functional food. To unlock its potential as a health food, this study investigates its polysaccharide composition. We first analyzed the structural characteristics of the Sanghuangporus vaninii polysaccharide, then examined its therapeutic effect on ulcerative colitis (UC) in mice, identified the bioactivity of its acidic polysaccharide fraction (SVP-A-3), and investigated its anti-inflammatory mechanism. We purified SVP-A-3, which has a molecular weight of 3.3 kDa and primarily consists of Gal, Glc, Man and GlcA. The specific rotation degree of SVP-A-3 is +18°, and its structure is right-handed. In vivo, results indicated that SVP-A-3 reduced glandular loss and intestinal mucosal tissue damage in mouse colons and decreased the number of inflammatory factors in colon tissue. The expression of p-AKT, p-ERK1/2, p-JNK1/2, p-p38, and p-p65 was down-regulated in the colon of C57BL/6 mice treated with SVP-A-3. Its specific mechanism may be associated with the regulation of NF-κB, MAPK, and AKT signaling pathways. Furthermore, in this paper, we found that SVP-A-3 could modulate the intestinal microenvironment and could significantly increase the abundance of probiotic Anaerostipes, Lactobacillus and Muribaculaceae. We concluded that SVP-A-3 demonstrated superior anti-inflammatory effects in in vivo animal experiments and has high exploitation potential. Our results provide important structural information about SVP and provide the basis for their further development and application.