Absorption of acylated anthocyanins from purple yam extract in rats.

Purple yam (Dioscorea alata L.) is a tuber widely distributed in the tropics and subtropics. We previously isolated several acylated anthocyanins from purple yam. In this study, purple yam extract was orally administered to rats and the absorption of the constituent anthocyanins was investigated. Acylated anthocyanins were detected in the plasma, confirming that they were absorbed into the body as their intact forms. The time required to reach the maximum anthocyanin concentration was 15 min, indicating rapid absorption into the blood. In addition, more than half of the total amount of anthocyanins excreted into the urine was excreted within the first 6 h after administration. To the best of our knowledge, this is the first report of the detection of characteristic acylated anthocyanins from purple yam in rat plasma and urine after oral administration.