Immunostimulant (1→3)-d-glucans from the cell wall of Cryphonectria parasitica (Murr.) Barr strain 263

A (1→3)-β-d-glucan with approximately 30% of the residues having a β-d-Glc-(1→6) branch is the main water-soluble component of the cell wall polysaccharide of Cryphonectria parasitica (Murr.) Barr strain 263. A (1→3)-glucan with both α and β anomeric linkages was found in the water-insoluble polysaccharide fraction. Both fractions possess immunological activity, being able to induce the production of either tumour necrosis factor α (TNF-α) or nitrite (NO2−).