Immunologically active polysaccharides from Centrosema pubescens.

Two polysaccharides with mean Mrs of 2.0×106 and 3.75×105, were isolated from powdered seeds of Centrosema pubescens by fractionation on Sephacryl S-300 HR. Chemical and spectroscopic studies indicated that they have a backbone chain composed of β-(1→4)-linked d-galactopyranose residues having branches composed of α-(1→5)-linked l-arabinofuranose residues at position 6 of d-galactose of the backbone chain. The polysaccharides showed reticuloendothelial system-potentiating activity in a carbon clearance test.