KINETICS AND ADSORPTION ISOTHERM OF C-PHYCOCYANIN FROM Spirulina platensis ON ION-EXCHANGE RESINS

C-phycocyanin is a natural blue dye extracted from Spirulina platensis, which has many applications in the food and pharmaceutical industries. In this paper the effect of pH and temperature on the adsorption of C-phycocyanin onto two different ion exchange resins (Streamline DEAE and Streamline Q XL) for expanded bed adsorption chromatography was investigated. Moreover, the kinetics and adsorption isotherm were evaluated. The equilibrium for the Q XL matrix was reached after 60 min, while for DEAE it was only reached after 140 min. C-phycocyanin showed the highest partition coefficient at pH 7.5 for both resins at 25 degrees C. The C-phycocyanin adsorption isotherm was very well represented by the Langmuir, Freundlich and Langmuir-Freundlich models, where the estimated values for Q(m) and K-d obtained by the Langmuir isotherm were, respectively, 33.92 mg.mL(-1) and 0.123 mg.mL(-1) for DEAE, and 28.12 mg.mL(-1) and 0.082 mg.mL(-1) for the Q XL matrix. A negative cooperativity was observed for C-phycocyanin binding when the Q XL matrix was used, while the cooperativity was purely independent using the DEAE matrix.