Helianthus annuus Leaf Ameliorates Postprandial Hyperglycaemia by Inhibiting Carbohydrate Hydrolyzing Enzymes Associated with Type-2 Diabetes

Diabetes mellitus is a chronic disease. Decreasing postprandial hyperglycemia by retarding glucose absorption through inhibiting carbohydrates digesting enzymes (α-amylase and α-glucosidase) is one of many approaches used for the management of this disease. This study was aimed at evaluating the normoglycaemic potential of Helianthus annuus leaf.
The effect of the in vitro inhibitory of different extracts (acetone, ethyl acetate and hexane) of the plant was assessed on the activities of diabetes-related enzymes (α-amylase and α-glucosidase).
The hexane extract of H. annuus leaf displayed the best inhibitory activity against α-amylase and α-glucosidase as indicated by the IC50 values (3.92 ± 0.02 mg mL-1) and (3.29 ± 0.12 mg mL-1), respectively. Lineweaver-Burk plot of inhibition of α-amylase and α-glucosidase by this extract showed that it was competitive and non-competitive mode, respectively.
H. annuus leaf possesses hypoglycaemic potential which may be due to the inhibition of pancreatic α-amylase and intestinal α-glucosidase.