Sequential recovery of phycobiliproteins and polysaccharides from Spirulina using a novel two-step process integrating adsorption and cross-flow dialysis

This study demonstrates a two-step process for separating valuable food components from Spirulina( Arthrospira ) biomass. First, the pigment-protein complexes, C-phycocyanin (CPC) and allophycocyanin (APC), were recovered using batch ion-exchange resin adsorption with Sepabeads TM . The adsorption process reduced CPC and APC concentrations from 2.52 × 10 -4 and 1.16 × 10 -4 mol m -3 to 4.37 × 10 -5 and 4.57 × 10 -5 mol m -3 , respectively, reaching equilibrium in 20 minutes. The adsorption process significantly improved protein purity, with CPC purity ratio increasing from 0.40 to 0.86 and APC from 0.18 to 0.27 in the resin-recovered proteins, demonstrating effective selective separation. Second, the pigment-depleted extract is processed using a crossflow dialyzer to concentrate polysaccharides, increasing their concentration from 0.12 g L -1 to 0.89 g L -1 after 100 minutes. The adsorption of pigment-protein complexes prior to dialysis prevents membrane fouling. This study showcases the potential of combining adsorption and membrane technologies for efficient separation and concentration of valuable food components from microalgae biomass, which can be applied in the development of functional foods and nutraceuticals.