Evaluation of alpha- amylase inhibition by Urtica dioica and Juglans regia extracts

OBJECTIVE(S): One strategy for the treatment of diabetes is inhibition of pancreatic α- amylase. Plants contains different chemical constituents with potential for inhibition of α-amylase and hence maybe used as therapeutic. MATERIALS AND METHODS: Urtica dioica and Juglans regia Linn were tested for α-amylase inhibition. Different concentrations of leaf aqueous extracts were incubated with enzyme substrate solution and the activity of enzyme was measured. For determination of the type of inhibition, Dixon plot was depicted. Acarbose was used as the standard inhibitor. RESULTS: Both plant extracts showed time and concentration dependent inhibition of α-amylase. 60% inhibition was seen with 2 mg/ml of U. dioica and 0.4 mg/ml of J. regia aqueous extract. Dixon plots revealed the type of α-amylase inhibition by these two extracts as competitive inhibition. CONCLUSION: Determination of the type of α-amylase inhibition by these plant extracts could provide by successful use of plant chemicals as drug targets.