Comparison of Different Methods for Carotenoid Extraction from Dunaliella Salina

Dunaliella salina (D. salina) is a unicellular marine alga known for its carotenoid ingredient. Carotenoid has been used in food industry as a coloring additive and as an antioxidant. In addition, it has anticancer, antiaging, and immune-modulatory properties. Different methods have been used for extraction of carotenoids from algae. This study evaluated different extraction methods for carotenoid and comparedthe carotenoid yield and extraction time for procedures.

In an experimental study, D. salina was isolated from Maharloo Lake in Shiraz, Iran. D. salina was centrifuged, dried, and suspended in methanol for further carotenoid extraction using different methods, namely ultrasound-assisted, supercritical fluid, microwave-assisted, electromantle, magnetic stirring, and maceration extraction methods.

Simultaneously, ultrasound-assisted, microwave-assisted, and electromantle extraction methods showed higher carotenoid yield and during a shorter time when compared with supercritical fluid, magnetic stirring, and maceration extraction methods. Since ultrasound-assisted extraction is a cold extraction method and ultrasound waves could release carotenoid and chlorophyll from broken cells to solvent quickly, the highest yields of carotenoid and chlorophyll were obtained during 10 min applying ultrasound-assisted extraction method. In contrast, the lowest yields of carotenoid and chlorophyll were undertaken by supercritical fluid extraction method.

Ultrasound-assisted extraction method was demonstrated to be a promising tool to recover higher value-added compounds from D.salina.