Evaluation of Angiotensin I-Converting Enzyme (ACE) inhibitory potential of some underutilized indigenous fruits of West Bengal using anin vitromodel

Abstract

Introduction.AngiotensinI-ConvertingEnzyme(ACE)isakeycomponentinregulationofblood pressure by virtue of the rennin-angiotensin system. ACE converts the inactive decapeptide, angiotensin I, into the potent vasopressor octapeptide, angiotensin II, and inactivates bradykinin, which has a vasodilating action. So, inhibition of ACE has become a major target in control of hypertension. It is well known that the consumption of fruits could provide health benefits by lowering the risk of chronic diseases such as metabolic syndrome diseases including type 2 diabetes and cardiovascular disease. Our current study was focused on investigating the ACE inhibitory property of a few underutilized minor fruits of West Bengal using an in vitro assay. Materials and methods. The potential antihypertensive activity of underutilized indigenous edible fruits of West Bengal, India, was evaluated by their ability to inhibit Angiotensin-Converting Enzyme (ACE). The ACE inhibitory property was assayed using ACE from rabbit lung and hippuryl-histidyl-leucine as the substrate. Nineteen fruit species belonging to 15 families were investigated. The percentage ACE inhibitory activities of these fruits were studied at 20 µg fresh weight of fruit extract per mL. The total phenol content of all these fruits was determined following the standard Folin-Ciocalteu method. Total flavonoid content was also measured. Results. The aqueous fruit extracts of the red variety of Trapa bispinosa, Phoenix sylvestris, Cicca acida, Achras sapota and Averrhoa carambola presented more than 75% ACE inhibition. On the other hand, Punicagranatum, Spondiaspinnata, Trapabispinosa (green) and Ziziphusmauritianashowed about 50% inhibition. Aegle marmelos, Annona squamosa, Annona reticulata, Feronia elephantum, Physalis peruvianaandSyzygiumjambosshowedlowactivity(< 50%inhibition).Discussions.Todatetherehasbeen no report on Angiotensin I-Converting Enzyme inhibitory activities of these underutilized minor fruits of West Bengal, India. During our study no correlation could be established between the % ACE inhibition and the total phenol or flavonoid content of these fruit extracts. So, it appears that non-phenolic components may also be responsible for ACE inhibitory activity. In our investigation we tried to establish the fact that the consumption of these underutilized minor fruits might have potential in managing cardiovascular diseases.