Study On The Purification Of Phycocyanin By Salting Out Method And Column Chromatography

This research was carried out to extract and purify phycocyanin from blue algae from Chaohu Lake by utilizing salting out methods.Thus,a two-step salting out was performed using Ammonium sulphate,Triammonium citrate,Sodium citrate and Sodium sulfate.The phycocyanin and the impurity solution collected at each phase were subjected to analysis by using UV-Vis spectrophotometer to identify the optimal dose of ammonium sulfate,triammonium citrate,sodium citrate and sodium sulfate.The optimal molar concentration for Ammonium sulphate,Triammonium citrate,Sodium citrate and Sodium sulfate in the first and second salting out process were 1.0 mol/L and1.7mol/L for Ammonium sulphate?NH₄?₂SO_4,0.7,mol/L and 1.3 mol/L for Triammonium citrate C₆H₁₇N₃O₇,0.5mol/L and 0.9 mol/L for Sodium citrate C₆H₅Na₃O₇,1.0mol/L and 1.3 mol/L for Sodium sulfate Na₂SO₄.After the two-step salting out processes,it was observed that higher molar concentrations can remove impurities in large quantities,and both purity and yield was greatly increased.The results indicate a purity of phycocyanin above 2.0 with a phycocyanin recovery relatively high.After the second salting out performed using?NH₄?₂SO_4,phycocyanin was further purified by ion exchange chromatography,and the Reagent-level phycocyanin was obtained.The types of fillers,pH of eluent,concentration of sample,speed of sample addition and salt concentration in eluent were studied.The optimum conditions were as follows:cellulose A-500,pH of eluent 7.0,concentration of sample1-2 mol/L,speed of sample addition 2 cm/min and NaCl concentration of eluent 0.25mol/L.Finally,reagent-grade phycocyanin with purity above 4.0 was obtained.