Optimization of Biopigment Extraction from <i>Dunaliella salina</i> Using Ultrasound: Perspectives for Microalgal Biorefineries

Abstract Natural pigments of microbial origin have attracted industrial interest due to their safety profile, environmental compatibility, and lack of carcinogenic effects. This study aimed to optimize the extraction of chlorophylls and carotenoids from Dunaliella salina , which was cultivated in bubble column photobioreactors, followed by biomass harvesting and ethanol‐based extraction assisted by probe ultrasound. A 2 2 factorial design was used to assess the effects of extraction time and ultrasound cycle. Results showed that extraction time significantly influenced all pigment extraction, favoring shorter durations, whereas the cycle was significant only for chlorophylls. The extraction conditions also enabled the recovery of β‐carotene, indicating a substantial production of pigments.