Kinetics of inhibitory action of Myrothamnus flabellifolius Welw. on the activities of α-amylase and α-glucosidase

Recently, efforts have been geared towards the development of alternative medicines to manage diabetes mellitus by searching for pharmacological agents with the ability to retard glucose absorption through inhibition of α-amylase and α-glucosidase. The present study investigated the in vitro antioxidant capability and inhibitory potential of Myrothamnus flabellifolius leaf extracts on the activities of α-amylase and α-glucosidase. The hydroethanol extract elicited significant α-glucosidase inhibitory effect (IC₅₀ = 0.50 ± 0.04 mg/mL) and a mild α-amylase inhibitory activity (IC₅₀ = 0.79 ± 0.04 mg/mL). The aqueous extract exhibited significantly higher DPPH scavenging ability, while the hydroethanol displayed most potent iron chelation, as well as superoxide and hydroxyl radical scavenging capabilities. A probe into the mode of inhibition revealed that the hydroethanol extract inhibited the two enzymes uncompetitively. It may be concluded that the hydroethanol extract of M. flabellifolius is a potential candidate for the management of non-insulin-mediated diabetes and the presence of phytochemicals like alkaloids, flavonoids, glycosides, phenol, saponin, tannin, phytosterol, and triterpene could be responsible for the elicited activity.