Chemical structure and anti-inflammatory effects on intestinal epithelial cells of a novel mannogalactan purified from Typhonium giganteum Engl.

Abstract

Inflammatory bowel disease (IBD) remains a pressing global health challenge due to its complex pathogenesis and limited treatment efficacy. Mannogalactans, abundant in certain algae and edible fungi, are recognized for their diverse biological functions, particularly their potent anti-inflammatory effects. Motivated by these findings, we hypothesized that Typhonium giganteum Engl. may contain structurally analogous mannogalactans with therapeutic potential against enteritis. To investigate, we isolated and purified a homogeneous polysaccharide, BFZ213, using hot water extraction, ethanol precipitation, and chromatographic techniques. Comprehensive structural analysis, employing methylation analysis, partial acid hydrolysis, 1-phenyl-3-methyl-5-pyrazolone (PMP) derivatization, infrared spectroscopy, HPLC, GC-MS, and NMR spectroscopy, identified BFZ213 as a novel mannogalactan (160 kDa). The backbone comprises 1, 3-linked mannose, 1, 2, 3-linked mannose, 1, 4-linked glucuronic acid, and 1, 2, 4, 6-linked galactose, with branching at the C-4 and C-6 positions of 1, 2, 4, 6-linked galactose, including 1, 4-linked galactose, 1, 6-linked galactose, terminal galactose, and arabinose. Bioactivity studies demonstrated that BFZ213 significantly suppressed TNF-α and IL-1β secretion in LPS-stimulated NCM460 cells and attenuated MAPK and NF-κB signaling by inhibiting the phosphorylation of p38, JNK, p65, and IκBα. These results highlight BFZ213 as a promising lead compound for IBD therapy, underscoring the therapeutic relevance of mannogalactans.