In vivo and in vitro studies on the absorption characteristics of β-cryptoxanthin in the intestine.

β-Cryptoxanthin (β-CRX) is a carotenoid abundantly present in the Satsuma mandarin (Citrus unshiu Marc.), one of the most popular fruits in Japan, and it is reported to have several health benefits. Although it is thought to have higher bioavailability than other carotenoids, the usual daily intake is small, and a good method to improve its bioavailability is needed. Hence we studied the effect of emulsification on the absorption characteristics of β-CRX in the intestine. Human trials showed that its serum transfer efficiency was statistically higher in the emulsified formulation than in fresh Satsuma mandarin juice. Caco-2 permeability studies indicated that emulsifiers preferentially accelerate the absorption of the non-esterified form of β-CRX, suggesting that emulsification is more effective for free β-CRX. This information might be useful to improve the efficiency of β-CRX serum transfer, as well as to increase the health benefits of β-CRX.