Separation And Purification Of Phycocyanin By Expanded Bed

Phycocyanin (PC) is a natural resource of protein, extensively used in many fields. The traditional separation and purification process for obtaining purified phycocyanin were time-consuming, low efficiency and highly cost. In this study, expanded bed adsorption (EBA) was used to purify phycocyanin to reduce the cost of operation and improve the purity of product.1,The basic properties of the expanded bed (400mm×16mm) made in our lab was investigated. The expansion rate of adsorbent increased with the increment of the inlet velocity. With the size and density of adsorbent decreased, the expansion rate increased. The expansion rate of macro-porous resins was higher than non-porous resins at the same velocity of fluid, and increased with the elevation of pore volume.2,The obvious deviation existed between the calculated settling rates and the simulated settling rates of resins. The relationship model of the two kinds of settling rates was established based on the pore volume, lnU_t =lnU'_t / (0.9815+0.1243V_g). The model for the prediction of the fluid velocity in the expanded bed of macro-porous resins at different expansion rate was also built, ln U = 1/klnU_t' +[(4.4+18d_P/D_e)U_t'1/kρ_Ld_P]/μlnε, k=0.9815+0.1243Vg. The prediction of the model is in good agreement with the results of experiments.3,The integration of the expanded bed with the packed bed chromatography was used to purify phycocyanin. Firstly, the crude extract from spirulina was purified by the expanded bed. The highest value of purity (A_620nm/A_280nm) of phycocyanin could be improved from 0.23 to 2.02, the concentration of phycocyanin was 2.15mg/mL, and the recovery of phycocyanin was 59.45%. Secondly, the sample obtained from the expanded bed passed through an ADS-7 packed bed (200mm×10mm) to remove contaminated proteins. Under the optimized conditions, the highest value of purity (A_620nm/A_280nm) of phycocyanin 2.20 was achieved. Through the purification by packed bed chromatography, the concentration of phycocyanin was 0.87mg/mL and the recovery of phycocyanin was 58.81%. The whole purification process took 7.0 hour, and the total recovery of phycocyanin was 34.96%.