ABSTRACT
Several studies suggest that ß-cryptoxanthin has a greater plasma response from its common food sources than other carotenoids such as ß-carotene and lycopene. The hypothesis of this study is that changes in plasma ß-cryptoxanthin concentrations will be greater than changes in plasma ß-carotene or lycopene concentrations even if these carotenoids are fed in a similar food matrix, such as citrus fruit. We tested this hypothesis by measuring changes in plasma concentrations of ß-cryptoxanthin, lycopene, and ß-carotene after feeding measured amounts of canned tangerines and pink grapefruit to healthy nonsmoking adult humans. Volunteers served as their own controls and received both citrus fruit treatments randomly. In the first study, 8 subjects ate single meals of 234-304g of tangerines or 60-540g of pink grapefruit. The second study compared changes in plasma carotenoid concentration caused by feeding 234g of tangerines or 540g of pink grapefruit to 11 subjects. Blood was collected 5 times within 24hours after each citrus meal. Carotenoid concentrations were analyzed by reversed-phase high-performance liquid chromatography. Plasma ß-cryptoxanthin concentrations increased within 5hours and then stabilized, remaining high throughout the 24hours measured. Plasma concentrations of lycopene and ß-carotene did not change. These results show that ß-cryptoxanthin concentrations increased after a citrus fruit meal, but lycopene and ß-carotene concentrations did not change after a similar citrus fruit meal. These results support our hypothesis that changes in plasma ß-cryptoxanthin are greater than changes in plasma lycopene or ß-carotene, even when these carotenoids are fed in a similar food matrix.
