Supercritical fluid extraction as a tool to valorize underexploited freshwater green algae

Carotenoids are natural antioxidants applied in food products; the most abundant carotenoid of marine macroalgae is fucoxanthin, which possesses antiproliferative activity; carotenoids also possess antioxidant, antimicrobial, and antihypertensive activity.

“Carotenoids are natural antioxidants and they are applied in different food products [18]. The most abundant carotenoid of marine macroalgae is fucoxanthin (Figure 4) and it possess antiproliferative activity [19,20]. Except for antiproliferative properties, carotenoids also possess antioxidant [21], antimicrobial, and antihypertensive activity [22].”

Extraction efficiency of phenolic compounds and carotenoids increased when EtOH is used as co-solvent compared to SC-CO2 without co-solvent.

“The extraction efficiency of phenolic compounds and carotenoids increased when EtOH is used as co-solvent when compared to the use of SC-CO2 without co-solvent [21,22].”

SC-CO2 was used mostly for extraction of polyphenols and carotenoids at pressures mostly 20-30 MPa and temperatures 40-60 °C, with some authors using ethanol as co-solvent.

“SC-CO2 was used mostly for the extraction of polyphenols and carotenoids where applied pressures were at range mostly of 20–30 MPa and some of the authors used ethanol (EtOH) as co-solvent [21,22,37,38], whereas, temperature was applied in the range 40–60 °C.”