Extraction of Astaxanthin from Haematococcus Pluvialis Microalgae Using Supercritical Carbon Dioxide

Abstract

Astaxanthin is a high-value carotenoid widely utilized in nutraceutical, pharmaceutical, cosmetic, and aquaculture industries due to its strong antioxidant properties and biological activity. Haematococcus pluvialis microalgae represent one of the richest natural sources of astaxanthin, necessitating efficient and environmentally sustainable extraction technologies for commercial production. The present study investigates the extraction of astaxanthin from Haematococcus pluvialis using supercritical carbon dioxide under controlled processing conditions. The research focuses on evaluating extraction efficiency, pigment recovery, process selectivity, and operational optimization associated with supercritical fluid extraction systems. Experimental analysis was conducted to examine the influence of extraction pressure, temperature, carbon dioxide flow rate, extraction time, particle size, and co-solvent addition on astaxanthin yield and product quality. Results demonstrate that supercritical carbon dioxide effectively penetrates algal cell structures and selectively extracts astaxanthin with minimal thermal degradation and solvent residue formation. The study further reveals that optimized pressure and temperature conditions significantly enhance solubility and mass transfer behavior, resulting in improved pigment recovery and extraction efficiency. The addition of suitable co-solvents contributed to enhanced extraction performance and improved recovery of polar carotenoid compounds. Comparative assessment with conventional solvent extraction methods confirms the advantages of supercritical carbon dioxide extraction, including lower environmental impact, solvent-free product quality, reduced oxidation risk, and improved preservation of bioactive compounds.