Phycocyanin is a major protein produced by cyanobacteria, but very few 
phycocyanin-producing strains have been reported. In the present study, response 
surface methodology (RSM) involving a central composite design for four factors 
was successfully employed to optimize medium components for increased production 
of phycocyanin from Phormidium ceylanicum. The production of phycocyanin and 
interactions between sodium nitrate, calcium chloride, trace metal mix and 
citric acid stock were investigated and modeled. Under optimized condition P. 
ceylanicum was able to give 2.3-fold increase in phycocyanin production in 
comparison to commonly used BG 11 medium in 32 days. We have demonstrated the 
extraction, purification and characterization of C-phycocyanin using novel 
method based on filtration and single step chromatography. The protein was 
extracted by repeated freeze-thaw cycles and the crude extract was filtered and 
concentrated in stirred ultrafiltration cell (UFC). The UFC concentrate was then 
subjected to a single ion exchange chromatographic step. A purity ratio of 4.15 
was achieved from a starting value of 1.05. The recovery efficiency of 
C-phycocyanin from crude extract was 63.50%. The purity was checked by 
electrophoresis and UV-Vis spectroscopy.