Résumé
Health benefits of fruits and vegetables could be attributed to the presence of a large diversity of phytochemicals, including carotenoids. The bioactivities of carotenoids greatly depend on their bioavailability that could be modulated by the presence of other dietary constituents. Because citrus juices contain diverse antioxidant phytochemicals, the effects of flavonoids and ascorbic acid on intestinal carotenoid uptake were investigated. Experiments were conducted by using a Caco-2 cell monolayer exposed to micelles enriched in beta-cryptoxanthin b-CX and beta-carotene b-C, in the presence of hesperetin HES, hesperidin HES-G, naringenin, acid ascorbic AA and iron. After 5 or 24 h incubation, both HES-G and HES significantly increased b-CX and b-C uptake by around 1.6-fold. Interestingly, AA was shown to eliminate the enhancing effect of HES-G by decreasing significantly the cellular uptake of b-CX and b-C by 10% after 5 h incubation. Iron decreased the carotenoid uptake, but HES-G was shown to counteract the iron effect, certainly due to its iron-chelating activity.