Purification, characterization and biotechnological potential of new exopolysaccharide polymers produced by cyanobacterium Anabaena sp. CCC 745

In the present study, the isolation of cyanobacterium CCC 745 was performed from samples collected from the paddy fields of Manipur state of India and was found related phylogenetically with Anabaena sp. The content of carbohydrate, protein, lipid, moisture, and ash in biomass of CCC 745 was 30.60%, 34.99%, 26.64%, 1.44%, and 6.33% respectively. The exopolysaccharide (EPS) production (320.21 mgl−1) was found maximum after 30 days cultivation in BG 11 medium supplemented with CaCl2 (10 mM). Size exclusion chromatography (SEC) was used to purify capsular polysaccharide (CPS) and released polysaccharide (RPS) separately, and molecular weight of CPS and RPS were 30.29 and 19.57 KDa, respectively. The carbohydrate was the main component for both EPSs, which are heteropolysaccharide and composed of glucose, xylose, rhamnose, and glucuronic acid. The backbone of both EPSs was made of [→4)-Glcp-(1→] and →4)-Rhap-(1→ linkage. The charges of both EPSs were found negative. The aqueous solution of both EPSs exhibited classically pseudoplastic fluid behavior. The productivity of exopolysaccharide was found noteworthy, and EPSs exhibited significant antioxidant and scavenging activity. Therefore, Anabaena sp. CCC 745 is considered as a promising feedstock for several industrial applications. [Display omitted] •Identification and characterization of cyanobacteria.•Production and purification of cyanobacterial exopolysaccharides (EPS).•Structure elucidation and characterization of cyanobacterial EPSs.