Solubility of purified lutein diesters obtained from Tagetes erecta in supercritical CO2 and the effect of solvent modifiers

Purified lutein diesters deposited on commercial nonporous glass beads were solubilized in supercritical CO2 in a computerized batch extractor, and their solubilities were compared to their solubilities in hexane. Densities of 0.7, 0.8, and 0.9 g/mL were evaluated without modifiers. Both pressure and temperature increased solubility, although temperatures >50 degreesC promoted carotenoid loss as determined by mass balance. Solubility was enhanced by the use of modifiers and was related to their log P. Chloroform (log P = 2) increased 2.8 times the amount of solubilized lutein diesters compared to pure CO2 at the same extraction conditions (0.9= g/mL and 40 degreesC) to yield 65% of the amount extracted with hexane. Supercritical CO2 extraction of lutein diesters could represent a cleaner technology as compared to the current industrial use of hexane with important; ecological and health-related implications.