Screening of anti-oxidant, anti-diabetic and hepatoprotective activities of selected medicinal plants

Abstract

In the present study the Bauhinia variegata roots, Schrebera swietenioides fruits and Tectona grandis bark were selected for antioxidant, antidiabetic and hepatoprotective activity study. All the plant parts (Crude drug) were shade dried, powdered, standardized and subjected for the extraction with 95% ethanol and petroleum ether (40-60and#61616;C) in a soxhlet apparatus and with chloroform water by cold maceration method. Obtained extracts exhibited the presence of flavonoidal glycosides, tannins, carbohydrates, quinones, terpenoids and sterols constituent in them, when subjected to phytochemical investigation. The different solvent extracts of selected medicinal plants were tested for their antioxidant activity by DPPH model. It has been observed that antioxidant activity exerted by ethanolic extract of selected plants exhibited maximum percentage inhibition. Hence, they were further screened for antidiabetic and hepatoprotective activity. The acute toxicity study for these extracts revealed that selected medicinal plants were safe up to dose of 2000 mg/kg, hence, 1/10th of this lethal dose i.e. 200 mg/kg b.w. was taken as effective dose (therapeutic dose). When these extracts i.e. ethanolic extract of Bauhinia variegata root (200 mg/kg), Tectona grandis bark (200 mg/kg) and Schrebera swietenioides fruit (200 mg/kg) subjected for antidiabetic activity, it was confirmed that they possesses marked antihyperglycemic activity which was confirmed by improvement of glucose tolerance test and by lowering the blood glucose levels in alloxan-induced diabetic rats in single dose (acute) and multi dose (sub acute) treatment study. The extract treated groups shown prevention of reduction in body weight in diabetic rats. The hypoglycemic effect comparable to Glibenclamide (2.5 mg/kg) suggested that the active fractions may act by regenerating the and#946; cells in alloxan-induced diabetes.After administration of these extract to rats, it was found that TC, TG, LDL and VLDL level of all tested rats were significantly decreased.