Comparison of the absorption efficiency of alpha- and beta-cryptoxanthin in female Wistar rats.

Xanthophylls, such as lutein and zeaxanthin, have received increasing interest in recent years because of positive correlations between their consumption and the prevention of eye diseases. Numerous human intervention studies have been conducted with lutein to estimate the bioavailability from different formulations. The present study was designed to obtain basic data on the absorbance efficiency of the monohydroxylated counterparts of lutein and zeaxanthin: alpha- and beta-cryptoxanthin. A corn-oil-based diet comprising beta-cryptoxanthin from papaya purée and alpha-cryptoxanthin from green carrot leaves was fed to five female Wistar rats for 8 consecutive days at a rate of 17.3 nmol/d and 9.2 nmol/d, respectively. The identity of the xanthophylls in the supplement was ascertained by LC-(APCI)MS analyses, and xanthophylls present in liver and plasma samples were determined by HPLC/diode array detector (DAD). The beta-cryptoxanthin concentrations of rat livers in the treatment group were statistically distinguishable (P < 0.01) from those present in the livers of the control group that were fed a basic diet. Alpha-cryptoxanthin, the second xanthophyll present in the supplement, was not found in rat livers in the treatment group. Plasma samples were free of xanthophylls. This is the first report proving that beta-cryptoxanthin has a higher absorption efficiency than alpha-cryptoxanthin in rats, at least from a minimally processed oil-based xanthophyll supplement.