Comparison of Potential Antihypertensive and Antioxidant Between Aqueous Extract of Purple Sweet Potato Tuber and Captopril in Hypertensive Patients

Abstract Hypertension is a cardiovascular disease that accompanied by oxidative stress. Treatment of hypertension with conventional drugs such as captopril could be expected to cope oxidative stress, but often cause side effects such as cough. It is necessary to find an alternative medicine instead of captopril, which has antihypertensive and antioxidant activities. Purple sweet potato tubers has been studied as an antioxidant in vivo, and has shown to decrease blood pressure in hypertensive rats. The purpose of this study was to compare the aqueous extract of purple sweet potato and captopril in relation with theire effects on blood pressure and oxidative stress in hypertensive patients. This research was limited clinical trials with randomized pre - test and post- test control group design, with a population of hypertensive patients. A total of 30 hypertensive patients were included in this study and they were divided into three groups of 10 patients each. The control group was given captopril only, treatment-1 group was given a purple sweet potato aqueous extract only, and treatment-2 were given a combination of captopril and purple sweet potato extract. This treatment was carried out for four weeks. The results showed that all treatments significantly (p<0.05) decreased the blood pressure and blood MDA levels. However a significant (p<0.05) increase in SOD was resulted from the group given aqueous extract of purple sweet potato tuber, while in the group given captopril, an increase in SOD was not significant ( p > 0.05 ). The conclusion from this study is that the aqueous extract of purple sweet potato obviously decreased the blood pressure and blood MDA levels that comparable to captopril, and a better ability to increase blood SOD levels in hypertensive patients. Keywords: Purple sweet potato, captopril, antioxidant, hypertensive patients