Abstract
Four Nigerian medicinal plants used for the treatment of various ailments in traditional ethnomedicine were evaluated for their anti-diabetic potential. The plants Irvingia gabonensis (O'Rorke) Bail, Eucalyptus torreliana F.v. Muell, Securidata longependuculata Fers and Murraya paniculata (L.) Jack were used in the study. Only the aqueous extract of I. gabonensis exhibited a potent maltase-inhibitory activity with an IC50 of 0.10mg/mL, as well as a sucrase-inhibitory activity (IC50 of 0.11mg/mL), whereas α-amylase inhibitory activity was quite poor (IC50 of 0.53mg/mL). A significant lowering of the blood glycemic response to maltose ingestion in 8-week old Sprague-Dawley rats was observed at a dose of 300mg/kg, in response to significant reduction in postprandial insulin response level.