PRODUCTION, ISOLATION AND PRELIMINARY CHARACTERIZATION OF THE EXOPOLYSACCHARIDE OF THE CYANOBACTERIUM SPIRULINA-PLATENSIS

The soluble exocellular polysaccharide secreted by the filamentous cyanobacteria Spirulina platensis is a primary metabolite. It is formed by ten different types of monomer units including six neutral sugars (xylose, rhamnose, fucose, galactose, mannose and glucose in the proportions 1.3/0.3/0.7/2.7/traces/2), two unidentified sugars, two uronic acids and sulphate groups accounting for 40% and 5% respectively of the mass of the molecule. This polysaccharide displays a non Newtonian behaviour and a strong pseudoplastic characteristic that may originate in the polyelectrolytic property of the molecule.