Comparative study of the extraction methods for recovery of carotenoids from algae: extraction kinetics and effect of different extraction parameters

Carotenoid extraction from algae is currently under intensive research due to the increased demand of naturally occurring compounds, which are especially rich in desired biologically active isomers. Furthermore, natural carotenoids exhibit higher stability compared to synthetic ones. Conventional liquid extraction suffers from several drawbacks, such as high amounts of solvent needed, and several extraction steps. In this work carotenoid extraction from algae with different methods, such as microwave and ultrasound assisted extraction as well as pressurized liquid extraction and extraction with supercritical CO₂ and ethane, was summarized together with modelling of extraction kinetics. In addition carotenoid availability, algae pretreatment, stability of extracts, their antioxidative and antimicrobial activities as well as downstream processing and storage of algae extracts have been reviewed. As a conclusion it can be stated that carotenoid extraction is complex demanding optimization of the carotenoid yield and antioxidative stability, which are often inversely proportional.