COMPARATIVE EVALUATION OF ANTI-DIABETIC ACTIVITY AND ALPHA-AMYLASE INHIBITORY ACTIVITY OF METHANOLIC EXTRACTS OF LEAVES & ROOTS OF Thespesia lampas (cav.) dalz & gibs AGAINST STREPTOZOTOCIN INDUCED DIABETIC RATS
Thespesia lampas Dalz and Gibs (Malvaceae) is considered in the system of folklore medicine for the treatment of diabetes. The present study was designed for comparative study of the anti-diabetic activity and alpha-amylase in-vitro inhibitory activity of methanolic extracts of leaves and roots of Thespesia lampas (METLL and METLR) at different doses by oral administration in streptozotocin (STZ) induced diabetic rats. Anti-diabetic activity was evaluated by administration of METLL and METLR at doses of 400mg/kg body weight as a single dose per day to diabetic rats for a period of 28 days. The blood was collected from retro-orbital sinus puncture, under mild ether anaesthesia in plane capillary tubes. Serum obtained by immediate centrifugation of blood samples using semi ultra-cooling centrifuge at 3000 rpm for 15 minutes at room temperature and was directly used for estimating serum glucose. The blood glucose levels were measured in the diabetic and non-diabetic rats by GOD-POD kit method. From the toxicity studies it was observed that the METLL and METLR were nontoxic up to 5g/kg body weight and phytochemical study showed the presence of flavonoids and glycosides. The results indicate that the METLL and METLR showed significant anti-hyperglycaemic effects on STZ induced diabetic rats when compared to that of standard drug (Glibenclamide 55mg/kg). A comparison was made between the extracts shows that the methanolic extract of T.lampas leaves (METLL) shown more significant (p<0.05, p<0.01) reduction in blood glucose level in streptozocin induced diabetic rats compared to the methanolic extract of T. lampas root (METLR). METLL and METLR showed good in-vitro alpha-amylase inhibitory activity as compared to standard acarbose with IC values of 56.37 and 44.92