Evaluation of toxicity and anti-amylase activity of 7, 8 dihydroxy coumarin (Daphnetin), a novel α-amylase blocker in vitro and in vivo

Management of postprandial blood glucose is a measure in regulating the blood sugar concentration. This paper evaluates the anti-amylase property of a natural compound 7,8 dihydroxycoumarin (daphnetin) both <i>in vitro</i> and <i>in vivo</i>. The inhibitory effect of daphnetin was evaluated against salivary (HSA) and pancreatic α-amylases (PPA) and α-glucosidase (AG) <i>in vitro</i>. Enzyme kinetics studies revealed that the inhibition of HSA, PPA and AG by daphnetin was competitive in nature. Pretreatment with daphnetin was found to inhibit the amylases <i>in vivo</i> as confirmed by the oral starch tolerance test (OSTT). No adverse effect of daphnetin was observed on serum markers and organs like liver, kidney and small intestine. The impact of the inhibitory effect of daphnetin in <i>in vivo</i> was comparable to the positive control, acarbose in all aspects.