Fast centrifugal partition chromatography for C-Phycocyanin purification from Limnospira platensis using eutectic solvent-based biphasic systems

The development of sustainable separation strategies for high-value bioproducts from microalgae is essential for advancing integrated biorefinery approaches. This study investigates the use of eutectic solvent (ES)-based biphasic systems for the selective separation of C-phycocyanin (C-PC), a water-soluble pigment-protein complex, from the crude extract of Limnospira platensis ( L. platensis ). Two ES combinations were selected based on phase stability and partitioning behavior: (i) a hydrophilic ES composed of glucose:glycerol:water (1:2:2.5) diluted with deionized water and paired with the hydrophobic ES decanoic acid:menthol (2:1), and (ii) the same hydrophilic ES diluted with phosphate buffer solution (14 wt% ) and combined with a hydrophobic ES comprising octanoic acid:decanoic acid:dodecanoic acid (3:2:1). These systems were evaluated using ultra-fast centrifugal partition chromatography (FCPC) under optimized conditions to enhance phase retention and resolution. The first system demonstrated effective separation with partition coefficients of 1.53 for C-PC and 0.50 for chlorophyll, achieving high purity at low pigment concentrations (15.9 mg C-PC ∙L −1 purity 5 times higher towards total proteins and chlorophylls). In contrast, the second system yielded more concentrated fractions (up to 615.9 mg C-PC ∙L −1 purity 5 and 0.87 times higher towards total proteins and chlorophylls, respectively) but exhibited low selectivity, with both pigments presenting similar partition behavior (K p ≈ 0.03). Overall, the results feature the potential of ES-based systems for pigment purification and highlight the trade-offs between resolution, purity, and concentration. • Valorization of L. platensis by recovering C-phycocyanin. • ES-based biphasic systems to separate C-PC from proteins and chlorophylls . • FCPC as a simple, rapid, and feasible technology to purify C-phycocyanin. • FCPC as a technology with a straightforward scale-up.