Comparative evaluation of the anti-diabetic activity of Pterocarpus marsupium Roxb. heartwood in alloxan induced diabetic rats using extracts obtained by optimized conventional and non conventional extraction methods.

The aim of the present study was to assess the anti-diabetic activity of Pterocarpus marsupium Roxb. heartwood in alloxan induced diabetic rats using extracts obtained by optimized conventional and non conventional extraction methods. Aqueous and ethanol extracts of Pterocarpus marsupium heartwood were prepared by conventional methods (infusion, decoction, maceration and percolation) and non conventional methods, such as ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE). The crude aqueous extracts were administered orally to both normal and alloxan induced male albino rats (Sprague-Dawley strain). The experimental set up consisted of 48 male albino rats divided into 6 groups: Normal control, diabetic control (sterile normal saline, 1 ml/100 g body weight), standard (gliclazide, 25 mg/1000g of body weight), groups 4-6 (crude aqueous percolation, optimized UAE and MAE extract, 250 mg/1000g of body weight). In acute treatment, the reduction of blood glucose level was statistically significant with the oral administration of UAE and percolation aqueous extracts to the hyperglycemic rats. In sub-acute treatment, the UAE aqueous extract led to consistent and statistically significant (p<0.001) reduction in the blood glucose levels. There was no abnormal change in body weight of the hyperglycemic animals after 10 days of administration of plant extracts and gliclazide. This study justifies the traditional claim and provides a rationale for the use of Pterocarpus marsupium to treat diabetes mellitus. The antidiabetic activity of Pterocarpus marsupium can be enhanced by extracting the heartwood by non conventional method of UAE.