| Abstract: |
Microalgal polysaccharides represent a high-value class of bioactive macromolecules with growing demand in pharmaceutical, nutraceutical, and functional food industries. Yet, inefficient and unsustainable extraction technologies severely constrain their industrial exploitation. Chlorella pyrenoidosa is a particularly attractive biomass source due to its rapid growth and high polysaccharide content, but its highly recalcitrant cell wall remains a major barrier to efficient recovery. The objective of this study was to optimize microwave-assisted extraction (MAE) conditions to maximize polysaccharide yield from Chlorella pyrenoidosa and to evaluate the effects of critical process variables using response surface methodology (RSM). Accordingly, a Box--Behnken experimental design was employed to systematically model and optimize the effects of extraction temperature, solid-to-liquid ratio, and irradiation time. Under optimized conditions (60 °C, 1:80 g/mL, 10 min), a maximum polysaccharide yield of 60.22% was achieved. The quadratic regression model exhibited excellent predictive accuracy (R² = 0.9893, p < 0.05), as confirmed by ANOVA. Compared with conventional extraction methods, the optimized MAE process delivered markedly higher extraction efficiency, substantial reductions in processing time and solvent usage, and superior alignment with green chemistry principles. Collectively, this work provides a scalable and industrially relevant green extraction framework that advances the valorization of microalgal biomass and supports the transition toward sustainable biorefinery platforms. [ABSTRACT FROM AUTHOR] |