Investigation of inhibition effect of folic acid (vitamin B9) on angiotensin-converting enzyme activity purified from human plasma

Abstract

Inhibition of the angiotensin-converting enzyme (ACE, EC 3.4.15.1) is one of the most important hypertension treatments. Here, ACE was purified from human plasma with affinity chromatography. The purity and molecule weight of ACE were identified utilizing the SDS-PAGE and viewed in two bands at around 60 kDa and 70 kDa on the gel. KM and Vmax constants from the Lineweaver-Burk graphic were computed to be 0.6 mM and 175.44 (µmol/min).mL-1 , respectively. The effects of folic acid (vitamin B9) on purified ACE were studied. Folic acid on purified ACE demonstrated an inhibitory efficacy. The IC50 value for folic acid was calculated to be 127.94 µM. Kind of inhibitory and Ki constant for folic acid were defined. The kind of inhibitory for folic acid was found as non-competitive inhibitory. Ki constant was computed to be 226.59 µM for folic acid. In this study, it was concluded that folic acid, which shows an inhibitor efficacy on ACE, may have both therapeutic and protective impacts against hypertension.