Application of continuous supercritical anti-solvents for rapid recrystallization and purification of zeaxanthin dipalmitates from de-glycosides of Lycium barbarum fruits

This study employed column elution fractionation coupled with supercritical anti-solvent recrystallization to isolate the purest zeaxanthin dipalmitates (ZP), one of the eye-protecting compounds in the Lycium barbarum fruits. The amount of ZP increased to 983 mg/g in liquid anti-solvent precipitates with 29.1% recovery and increased to 929 mg/g in supercritical anti-solvent precipitates with 59.6% recovery, respectively from the ultrasonic acetone extract. Experimental data showed that supercritical anti-solvent recrystallization is feasible in producing platelet type precipitates within a few minutes. These ZP compounds exhibit anti-oxidative abilities by proliferating human adult retinal pigment epithelial cells (from 22% to 31%); though it was a meager increase when compared to those of algal 95% zeaxanthin (from 43% to 94%).