In-vitro antidiabetic and antioxidant activity of various leaf extracts of Detarium microcarpum

Detarium microcarpum commonly known as ''sweet detar'' has been used for centuries in Nigerian traditional system of medicine for the treatment of diabetes. The present study deals with the scientific evaluation of the in-vitro alpha amylase, alpha glucosidase and the antioxidant potential of various leaf extracts of the plant by examining the free radical scavenging activity on DPPH using Rutin, Gallic acid and Ascorbic acid as standards. The Total Phenolic Content (TPC) and Total Flavonoid Content (TFC) of the leaf extracts were also determined using standard methods. The ethyl acetate, aqueous, and crude leaf extracts of D. microcarpum showed a significant amount of phenolic content 2014.22mg, 933.33mg and 766.81mg of GAE/g of extract respectively. Total flavonoid content in the ethyl acetate, aqueous and crude leaf extracts was discovered to be also high with values of 132.90mg, 30.50mg and 49.50mg of rutin equivalent (RE)/ g of extract respectively. The radical scavenging activities of extracts were significantly higher at all concentrations used than the standard compounds. The half-maximal inhibitory concentrations (IC50) of D. microcarpum crude and aqueous leaf extracts on a-amylase and α-glucosidase were lower than that of the ethylacetate fraction but all were higher than that of Acarbose. The present study provides evidence that the leaf extract of D. microcarpum is rich in flavonoids and other polyphenolic compounds and also possesses potent alpha amylase, alpha glucosidase and antioxidant activities and this may justify its use in ethnomedicine in the management of diabetes.