New approaches for the selective extraction of bioactive compounds employing bio-based solvents and pressurized green processes

Solvent selection is a key factor in the development of processes for the extraction of bioactive compounds from natural sources such as algae. The aim of this work was the use of bio-based solvents for the selective extraction of fucoxanthin from P. tricornutwn, using pressurized technologies. In this regards, the application of Hansen solubility approach reduced the list of candidate solvents for pressurized liquid extraction (PLE) to four: ethyl acetate, ethyl lactate, d-limonene and ethanol. The use of theoretical calculations narrowed the search of suitable solvents, thus making the process greener. Among the bio-based solvents proposed, d-limonene was the most selective, although it was not able to recover all the fucoxanthin present in the biomass unless a continuous extraction aided by supercritical CO2 was used. The other three solvents tested showed good recoveries of fucoxanthin, but were less selective, following the decreasing order: ethyl acetate > ethyl lactate > ethanol.