Djulis (Chenopodium formosanum) and its bioactive compounds' effect on vasodilation, angiotensin-converting enzyme activity (ACE) and hypertension, in vitro and in vivo, were evaluated. Rutin, betanin and another 13 compounds were observed in the water extracts of djulis (WECF) using HPLC-DAD and HPLC-MS/MS analysis. WECF, rutin and betanin showed significant induction of nitric oxide and prostacyclin as well as expression of eNOS and COX-2. In addition, WECF, rutin and betanin showed a marked inhibitory effect on ROS generation, peroxynitrite levels and ACE activity. Oral administration of WECF, rutin and betanin lowered systolic and diastolic blood pressures of spontaneously hypertensive rats. The ACE activity in the plasma of WECF-, betanin- and rutin-administrated groups was lower than the untreated group. Overall, WECF bioactive compounds could potentially be used as functional ingredients for preventing hypertension.
