Elucidating supercritical fluid extraction of fucoxanthin from algae to enable the integrated biorefinery.

[Display omitted] • Literature differs on fucoxanthin-optimized supercritical extraction conditions. • Statistical analyses of literature data identify 3 predictors of fucoxanthin yield. • Experiments establish how tunable solvent polarity drives fucoxanthin recovery. • Extractions on fucoxanthin standard vs. algae show hindrance of the algae matrix. • Fucoxanthin selectivity over chlorophyll is observed in supercritical CO 2 systems. The emerging nutraceutical, fucoxanthin, shows promise as a high-value product to enable the integrated biorefinery. Fucoxanthin can be extracted from algae through supercritical fluid extraction (SFE), but literature does not agree on optimal extraction conditions. Here, a statistical analysis of literature identifies supercritical carbon dioxide (scCO 2) density, ethanol cosolvent amount, and polarity as significant predictors of fucoxanthin yield. Novel SFE experiments are then performed using a fucoxanthin standard, describing its fundamental solubility. These experiments establish solvent system polarity as the key knob to tune fucoxanthin recovery from 0% to 100% and give specific operating conditions for targeted fucoxanthin extraction. Further experiments compare extractions on fucoxanthin standard with extractions from Phaeodactylum tricornutum microalgae to elucidate the effect of the algae matrix. Results show selectivity of fucoxanthin over chlorophyll in scCO 2 microalgae extractions that was not seen in extractions with ethanol, indicating a benefit of scCO 2 to design selective extraction schemes. [ABSTRACT FROM AUTHOR]