Single-step chromatography for simultaneous purification of C-phycocyanin and allophycocyanin with high purity and recovery from <Emphasis Type="Italic">Spirulina</Emphasis> (<Emphasis Type="Italic">Arthrospira</Emphasis>) <Emphasis Type="Italic">platensis</Emphasis>

The cyanobacterium Spirulina (Arthrospira) platensis is a good source of phycobiliprotein purification. C-phycocyanin (C-PC) is the major phycobiliprotein, while allophycocyanin (APC) is less abundant in S. platensis. Previously reported methods for C-PC purification are only able to offer either high purity or high efficiency. This paper describes one-step anion exchange chromatography method with continuous pH gradient elution for simultaneous purification of C-PC and APC with high purity and high recovery. Crude C-PC and APC were extracted and concentrated by ammonium sulfate fractionation at saturation of 25% and 60%, then purified on a DEAE-Sepharose Fast Flow chromatography column with continuous pH gradient elution from pH 5.0 to 3.6. After this single-step chromatography, C-PC and APC with high purity and recovery were simultaneously obtained. The purity ratios of C-PC and APC reached 5.59 (A₆₂₀/A₂₈₀) and 5.19 (A₆₅₀/A₂₈₀), respectively. Their purity was further demonstrated by electrophoresis and fluorescence emission spectroscopy. Moreover, the total recovery yield of pure C-PC and APC were 67.04% and 80.0%, representing 111.83 and 29.28 mg·g⁻¹ lyophilized weight, respectively. The obtained C-PC and APC remained stable over a pH range of 4–9. This purification method for high purity and recovery of C-PC and APC proved to be fairly efficient compared with previously reported methods.