Studies on Fungal Polysaccharides. IX. The Acidic Polysaccharide from the Cell Wall of Rhizopus nigricans

Main polysaccharide from the cell wall of Rhizopus nigricans, [α] D-70.5°, is a highly heterogenous glycan, composed of fucose, mannose, galactose, and glucuronic acid in an approximate relative ratio of 11 : 1 : 3 : 10. The results of periodate oxidation, Smith degradation, and partial hydrolysis indicate that the chemical structure of the polysaccharide is in a form oxidizable with periodate and greatly labile to mineral acid. The alkali-soluble but water-insoluble fragment of the cell wall contains uronic acid, glucosamine, and amino acids with small amounts of fucose, mannose, and galactose.