Production, large-scale extraction and purification of phycocyanin by potential of different strains of cyanobacteria isolated from various environments

Abstract

Abstract Blue-green cyanobacteria, which have attracted great interest in recent years due to their potential applications in biotechnology, have an essential ability to synthesize natural pigments of different colors. The chosen study is aimed at investigating the strain with the highest phycocyanin yield among the five cyanobacterial strains isolated from the wastewaters of Porsuk river, thermal springs, and boron-bearing waters of Eskişehir county of Turkey, and optimized studies, purification, and characterization for increasing the phycocyanin yield. At the initial stage, the phycocyanin yield was analyzed by applying four different extraction methods - freeze-thawing, sonication, homogenization, and treatment with lysozyme - to the selected strains. The most appropriate strain sonication method was selected and thermophilic Geitlerema sp was obtained with 116 ± 0.18 mg g− 1 phycocyanin. The crude extract obtained following the optimized studies was first purified by solid ammonium sulfate precipitation/dialysis at 50% and 75% saturation, and then by ion-exchange chromatography using two anionic resins (DEAE -cellulose, and Q -sepharose). The purity rate determined in the spectrum was recorded as 4.12 with 48.9% recovery (A620/A280). The molecular weights of the α and β subunits were found to be 17 kDa to 19 kDa, respectively, by characterization using the SDS-PAGE method. In addition, the effect of purified thermal phycocyanin at different temperatures was examined, the CR value of its pigment was determined to be stable by resisting at high temperatures up to 60Cº. Generally, in the study, a thermostable C-phycocyanin was purified from Geitlerema sp, which may be differentiated commercially from other mesophilic species.