β-Cryptoxanthin from Citrus Juices: Bioaccessibility and Uptake by Caco-2 Cell Culture Model

beta-cryptoxanthin (beta-CX), belonging to the xanthophyll sub-class of carotenoids, is mainly found in citrus fruit in both free and ester forms. Due to the lack of knowledge on the intestinal uptake of beta-CX, especially the ester forms, our purpose was to study the bioaccessibility of carotenoids from citrus juice. Carotenoid uptake was evaluated by incorporating carotenoid-rich micelles (from the in vitro digestion) or synthetic micelles (made from synthetic lipids and carotenoids purified from citrus juice) to human intestinal cells (Caco-2 TC7 clone). The uptake efficiency of beta-CX esters was compared to free beta-CX. Our results suggested that esters were partially hydrolyzed during the in vitro digestion. The bioaccessibility of free beta-CX exceeded that of beta-carotene and beta-CX esters. These results showed a preferential uptake by Caco-2 cells of beta-carotene and free beta-CX compared to the two esters for all types of micelles tested. In the case of micelles from in vitro digestion, the uptake of beta-carotene, free beta-CX and beta-CX esters by Caco-2 cells was 14.3 +/- 1.8; 3.9 +/- 0.9; 0.7 +/- 0.08 The present study provides the first report on assessment of beta-CX (free and esters) uptake by differentiated Caco-2 cells.