Absorption, storage and distribution of β-cryptoxanthin in rat after chronic administration of Satsuma mandarin (Citrus unshiu MARC.) juice.

Fruits and vegetables contain numerous antioxidants, such as carotenoids. Recent epidemiologic studies have demonstrated that a high dietary consumption of fruit and vegetables rich in carotenoids or with high serum carotenoid concentrations results in lower risks of certain cancers, diabetes, and cardiovascular disease. These results indicate that absorbed carotenoids are stored in various organs. Previously, we found that β-cryptoxanthin, found especially in Satsuma mandarin (Citrus unshiu MARC.), is easily absorbed and can also survive for a relatively long time in the human body; however, little is known about the absorption, storage, and tissue distribution of β-cryptoxanthin. In this study, we measured serum and the content of β-cryptoxanthin in several rat tissues after chronic ingestion of Satsuma mandarin extract rich in β-cryptoxanthin. Rats were fed a standard commercial diet containing Satsuma mandarin extract (containing β-cryptoxanthin at 11.7 mg/kg diet) for eight weeks. After 3 h of fasting, serum, liver, spleen, kidney, lung, heart, testis, brain, and epididymal fat were collected. The concentrations of β-cryptoxanthin in serum and tissues were evaluated by high-performance liquid chromatography. There was a wide range in the tissue levels of β-cryptoxanthin; liver had the greatest value, with 1265.3 ng/g tissue, followed by spleen, kidney, lung, heart, brain, and testis. Epididymal fat had the lowest value, with 6.99 ng/g tissue. β-Cryptoxanthin was also detected in serum in a concentration of 5.76 ng/mL. These results indicate that β-cryptoxanthin is easily absorbed and accumulated in several organs.