The Chemical Structure of an Antitumor Polysaccharide in Fruit Bodies of Grifola frondosa (Maitake)

Abstract

A polysaccharide was extracted from fruit bodies of Grifola frondosa (maitake), and the chemical structure and antitumor activity were studied. The extracted polysaccharide could be hydrolyzed by /β-glucanase into glucose, indicating it to be a β-glucan. The sample gave methyl 2.3.4.6- tetra-O-, methyl 2,4,6-tri-O-, methyl 2,3,4-tri-O- and methyl 2,4-di-O-methylglucoside in the molar ratio of 4:2: 1:4 on methylation. In the carbon-13 nuclear magnetic resonance spectrum, the signals of C-6’ (related to (1–6) bonding) and C-3’ (related to (1–3) bonding) were observed in addition to those of free C-6 and C-3. These results indicate that the major chain is made up of β-1.6-linked glucose residues with branches of β-1,3-linked glucose. This glucan inhibited the growth of Sarcoma 180 tumor in ICR mice. © 1987, The Pharmaceutical Society of Japan. All rights reserved.