Bioflocculant exopolysaccharide (EPS) production by ten (10) cyanobacterial strains during their photoautotrophic growth was investigated. Lyngbya sp. BTA166 and Anabaena sp. BTA35 produced highest levels of EPS along with highest flocculating activity amongst the studied strains. 16S rRNA nucleotide sequencing and BLAST analysis of nucleotide sequences were used to identify the cyanobacterial strains. The sequences were deposited in GenBank and accession numbers were obtained as KJ830952 and KJ562184, respectively. Studies on the effect of incubation period on EPS production revealed that highest EPS production was observed during stationary growth phase and late phase of growth. Biochemical composition of the exopolysaccharides from the two potential strains was also investigated. The cyanobacterial EPS consisted of soluble protein and polysaccharide that included substantial amounts of neutral sugars and uronic acid. The flocculant bound a cationic dye, alcian blue, indicating it to be polyanionic. The results of these experiments indicate that strains Lyngbya sp. BTA166 and Anabaena sp. BTA35 are good candidates for the production of EPS which could be utilized in industrial or commercial applications as an alternative to synthetic and abiotic flocculants
