Vegetos

Abstract

Plantains (Musa sapientum Linn. var. paradisiaca) have been reportedly used in folk medicine for the management/prevention of hypertension and other cardiovascular diseases. However, its peel which has continued to be a major waste in some part of the world has been shown to be rich in phenolic compounds. Hence, this study sought to investigate the inhibitory effects of the phenolic extract of different plantain peels on key enzyme linked to hypertension (angiotensin I converting enzyme, ACE) and antioxidative properties in vitro. The phenolic extracts of the different plantain (unripe, ripe and over ripe) peels were extracted using methanol – 1M HCl solution (1:1 v/v). Thereafter, the ACE inhibitory study and antioxidant capacity of the extracts were investigated. The results revealed that all the phenolic extracts inhibited ACE in a dose dependent manner (0 – 25 μg/ml); however, as revealed by the IC50 (extract concentration causing 50% inhibition on ACE activity) values, the unripe plantain peel extract (IC50 = 2.70 μg/ml) had the highest inhibitory effect while the brown plantain peel extract (IC50 = 11.04 μg/ml) had the least. In addition, all the phenolic extracts exhibited strong antioxidant activities as typified by their ABTS radical scavenging ability and reducing property with the unripe plantain peel extract showing the highest activities. The inhibition of the ACE, and antioxidative properties by the phenolic extracts could be attributed to the additive and/or synergistic action of the phenolics and indicate some possible antihypertensive potential. Therefore, the phenolic extracts from plantain peels could be harness as a cheap dietary approach to the management and prevention of hypertension and other cardiovascular diseases associated with oxidative stress.