COMPARATIVE STRUCTURAL STUDIES ON ACIDIC HETEROPOLYSACCHARIDES ISOLATED FROM SHIROKIKURAGE, FRUIT BODY OF TREMELLA-FUCIFORMIS BERK, AND THE GROWING CULTURE OF ITS YEAST-LIKE CELLS

Acidic heteropolysaccharides, D-glucurono-D-xylo-D-mannans were isolated from the water- and alkaline extracts of the fruit body of Tremella fuciformis Berk. Similar polysaccharides were isolated from the growing culture of the haploid cells of two strains (T-19 and T-7) of T. fuciformis, when they were cultured in sucrose or glucose-yeast extract medium. The extracellular polysaccharides contain, D-glucuronic acid, D-xylose and D-mannose [molar ratios, 1.3: 1.0: 3.5 (T-7) and 0.8: 1.0: 2.1 (T-19)], and, in addition, small proportions of l- fucose and O-acetyl groups. Méthylation and Smith degradation studies indicated that both fruit body and extracellular polysaccharides are built up of α-(l→3)-linked D-mannan backbone chain to which β-linked D-glucuronic acid and single or short chains of β-(1→2)-linked D-xylose residues are attached at the C-2 position. L-fucose residues in the extracellular polysaccharides may form the single branches. The structural features of these polysaccharides are discussed in comparison with the similar polysaccharides from other fungi. © 1979 Taylor & Francis Group, LLC.