Effect of pH increasing of Wuluh star fruit (Averrhoa bilimbi L.) juice on vasodilatation activity

Abstract

Wuluh star fruit (Averrhoa bilimbi L.) is Oxadiliaceae family which can be used as an antihypertensive drug by ethnomedicine. A. bilimbi fruit juice is proven to lower blood pressure in preclinical testing and limited phase 1 clinical trials, where the mechanism of action is through vasodilatation of blood vessels. The taste of juice fruit is very sour, but there is no information about the effect of pH increasing of juice on vasodilatation activity in blood vessels. In this research, A. bilimbi fruits were made into juice, filtered, centrifuged to get the supernatant. The pH of juice was increased by NaOH and KOH addition. Vasodilatation activity of juice was tested on isolated organs of the aortic ring endothelium. The control that used was Kreb's-Henselheit solution with a pH approaching the tested juice solution. The result showed that an increase in the pH of A. bilimbi fruit juice caused a decrease in vasodilatation activity. The type of solution to increase the pH of juice also affected the changes in vasodilatation activity. It can be concluded that the pH increasing on juice of A. bilimbi fruit can decrease vasodilatation activity on isolated organs of the aortic ring endothelium.