β-Cryptoxanthin Selectively Increases in Human Chylomicrons upon Ingestion of Tangerine Concentrate Rich in β-Cryptoxanthin Esters

β-Cryptoxanthin is a major source of vitamin A, often second only to β-carotene, and is present in fruits such as oranges, tangerines, and papayas. Here, we studied the uptake of this carotenoid upon ingestion of tangerine juice concentrate, rich in β-cryptoxanthin esters. Increasing amounts of free β-cryptoxanthin were detected in chylomicrons and serum. Peak levels in chylomicrons were reached att= 6 h, and the concentration returned toward basal levels att= 9 h. No β-cryptoxanthin esters were detected in chylomicrons or serum, indicating efficient cleavage in the intestine before the carotenoid is incorporated into lipoproteins by the liver. Other xanthophyll esters, e.g., of zeaxanthin and lutein, were present in low amounts in the tangerine concentrate. As with β-cryptoxanthin, no esters appeared in serum or chylomicrons, suggesting that the cleavage of carotenoid esters prior to release into the lymphatic circulation occurs generally in human oxocarotenoid biokinetics.