Purification, structural elucidation, and anti-inflammatory activity of xylosyl galactofucan from Armillaria mellea

A xylosyl 1,3-galactofucan (AMPS-III) was isolated and identified as a novel anti-inflammatory agent from an edible fungus, Armillaria mellea. The characteristics chemical structure of AMPS-III including the linkages of compositional monosaccharides and structure of the repeat unit were depicted and elucidated by proton, carbon and two-dimensional nuclear magnetic resonance techniques. AMPS-III was chemically proposed to have a partial 4-O-xylosylated 1,3-linked α-d-galactosyl-interlaced α-l-fucan composed of a pentadecasaccharide repeat unit with a molecular mass approximately 13 kDa. AMPS-III significantly suppressed the release of tumor necrosis factor-α (TNF-α) and cytokine monocyte chemotactic protein-1 (MCP-1) in RAW264.7 macrophages and EAhy926 following LPS and TNF-α induction. The results provide helpful evidences for application of AMPS-III as anti-inflammatory food supplements.