PROCEDURES OF OBTANING OF EXOPOLYSACCHARIDES PRODUCED BY CYANOBACTERIA SPIRULINA (ARTHROSPIRA) PLATENSIS AND NOSTOC LINCKIA

Abstract

The dynamics of accumulation of total and acidic (sulfated) exopolysaccharides (EPS) produced by cyanobacteria Spirulina platensis and Nostoc linckia under the action of some chemical regulators at the two steps cultivation with the increasing of light at the second step were established. Procedures of EPS isolation from cyanobacteria Spirulina platensis and Nostoc linckia and the scheme of EPS production, obtaining and quantification have been developed. The synthesis of sulfated exopolysaccharides (till 91 mg/l) at the cultivation of spirulina in two stages was positively influenced by the variation of the light regime and the addition of carbon source with or without addition of Na2SeO3. Supplementing of the nutrient medium with sodium selenite (2 mg/l) and varying of light to 2500 lx in the 7th day of cultivation of cyanobacteria Nostoc linckia led to a maximum increasing in the amount of total and acidic exopolysaccharides (477 and 422 mg/g, respectively).