Supercritical fluid extraction for liquid chromatographic determination ofcarotenoids in Spirulina Pacifica algae: a chemometric approach

An experimental design procedure was used to investigate the effects of som e operating parameters on the supercritical fluid extraction of carotenoids beta -carotene, beta -cryptoxanthin and zeaxanthin from Spirulina Pacifica algae, a carotenoid-rich dietary product. Variables tested were temperatur e and pressure of the supercritical fluid, dynamic extraction time and perc entage of ethanol added as the modifier. Each variable was tested at three levels; 31 experiments were performed in random order. Analyses of the extr acts were performed by high-performance liquid chromatography with UV-Vis p hotodiode array detection. Analytical responses (chromatographic peak areas ) were processed by using a stepwise multiple regression analysis, in order to find polynomial functions describing the relationships between variable s and responses. For all the analytes the experimental conditions providing the highest extraction yield inside the experimental domain considered wer e found. Supercritical fluid extraction results obtained in these condition s were compared with those obtained by performing solvent extraction in ord er to evaluate the effectiveness of the supercritical fluid extraction proc edure. (C) 2001 Elsevier Science B.V. All rights reserved.