An immunoenhancing polysaccharide isolated from the aqueous extract of the fruit bodies of the mushroom Pleurotus florida blue variant was found to consist of D-glucose and D-galactose in a molar ratio of nearly 5 1 On the basis of sugar analysis methylation analysis periodate oxidation Smith degradation and NMR studies (H-1 C-13 DEPT-135 DQF-COSY TOCSY NOESY ROESY HMQC and HMBC) the structure of the repeating unit of the polysaccharide was established as [GRAPHICS] The molecule activated macrophages splenocytes and thymocytes (C) 2010 Elsevier Ltd All rights reserved