Improvement in the Sequential Extraction of Phycobiliproteins from Arthrospira platensis Using Green Technologies

Spirulina hides a treasure trove of colorful pigments—and a new green extraction method just made unlocking them cleaner and smarter.

Spirulina, the blue-green microalga famous as a superfood, is packed with phycobiliproteins—especially C-phycocyanin, a bioactive compound with promising health applications. But getting these pigments out has always been a messy, solvent-heavy affair. Now, researchers have crafted a two-step green extraction process that starts with supercritical carbon dioxide (SC-CO2) to pull out nonpolar pigments like chlorophyll and carotenoids, leaving the polar phycobiliproteins behind for a second extraction. The team compared conditions, finding that higher pressure (350 bar) and temperature (50°C) without ethanol boosted nonpolar pigment recovery. Then, using a simple phosphate buffer without ethanol, they successfully extracted phycobiliproteins from the leftover residue, yielding C-phycocyanin with a purity of 0.7—meeting food-grade standards. This sustainable method not only preserves antioxidant properties but also offers a scalable blueprint for pigment extraction from microalgae, bringing us closer to eco-friendly nutraceuticals.

Key Points

• Supercritical CO2 extraction boosts nonpolar pigment recovery
• Ethanol-free buffer yields phycobiliproteins from SFE residue
• C-phycocyanin purified to 0.7 food-grade purity