Objective: To explore the possible inhibitory potentials and mechanism by Mobola plum(Parinari curatellifolia) seeds crude methanol(CE) and flavonoid-rich(FE) extracts on angiotensin-1-converting enzyme(ACE Ⅰ).Method...Objective: To explore the possible inhibitory potentials and mechanism by Mobola plum(Parinari curatellifolia) seeds crude methanol(CE) and flavonoid-rich(FE) extracts on angiotensin-1-converting enzyme(ACE Ⅰ).Methods: The sensitivity and kinetic model of inhibition of CE and FE on ACE Ⅰ using N-[3-(2-furyl)-acryloyl]-Phe-Gly-Gly as enzyme substrate for ACE Ⅰ was evaluated by Michealis Menten approach. The inhibition mechanism was explored from Lineweaver–Burk model and IC_(50) was determined from Cheng–Prusoff empirical analysis.Results: The IC_(50) of CE and FE were 13.54 and 39.38 mg/m L, respectively. Both extracts exhibited mixed type inhibition with the inhibitory constant(K_i) of CE was between0.38 and 0.37 mg/m L while that of FE showed a two-fold increase(1.62 mg/mL and0.28 mg/mL). FE on ACE Ⅰ demonstrated positive cooperativity with a Hill's coefficient of1.89.Conclusions: The study reveals the superior ACE Ⅰ inhibitory potential of CE over FE and suggest that mixed inhibition pattern of the enzyme might be the underlying mechanism of antihypertensive activity.展开更多
文摘Objective: To explore the possible inhibitory potentials and mechanism by Mobola plum(Parinari curatellifolia) seeds crude methanol(CE) and flavonoid-rich(FE) extracts on angiotensin-1-converting enzyme(ACE Ⅰ).Methods: The sensitivity and kinetic model of inhibition of CE and FE on ACE Ⅰ using N-[3-(2-furyl)-acryloyl]-Phe-Gly-Gly as enzyme substrate for ACE Ⅰ was evaluated by Michealis Menten approach. The inhibition mechanism was explored from Lineweaver–Burk model and IC_(50) was determined from Cheng–Prusoff empirical analysis.Results: The IC_(50) of CE and FE were 13.54 and 39.38 mg/m L, respectively. Both extracts exhibited mixed type inhibition with the inhibitory constant(K_i) of CE was between0.38 and 0.37 mg/m L while that of FE showed a two-fold increase(1.62 mg/mL and0.28 mg/mL). FE on ACE Ⅰ demonstrated positive cooperativity with a Hill's coefficient of1.89.Conclusions: The study reveals the superior ACE Ⅰ inhibitory potential of CE over FE and suggest that mixed inhibition pattern of the enzyme might be the underlying mechanism of antihypertensive activity.
