Effect of isothermal and thermal diffusion on aqueous two-phase extraction for the purification of C-phycocyanin from Spirulina platensis

Aqueous two-phase extraction (ATPE) is effective for the purification of C-phycocyanin (CPC) from Spirulina platensis. Polyethylene glycol and potassium phosphate was used to purify the CPC. The influence of various different temperatures (dT) of process on purity (EP) partitioning and diffusion coefficient was evaluated. The optimal conditions for CPC purification was found at dT 25 degrees C. CPC purity increased to 2.337 from an initial purity of 1.106. The concentration and recovery yield were found to be the highest at dT 25 degrees C (13.932 g/L and 91.18, respectively), which was significantly higher than the conventional process. The dT affected the fluid viscosity variable, potentially due to a phenomenon which decreases the viscosity of the mixture and enhances the solvent solubility and diffusion capacity. The present work presented the diffusion coefficient in ATPE at various dT of the process. The isothermal diffusion coefficient (Di) significantly increased to dT. The Soret effect (S-T) and thermal diffusion coefficient (D-T) were obtained at a high dT, but it should not be greater than 25 degrees C. Hydrophobicity plays an important role in the thermal diffusion behaviour. A high diffusion coefficient is expected to result in the purification process due to high purity and efficiency. (C) All Rights Reserved