Glucose lowering eff ect of aqueous extract of Bauhinia tomentosa L . on alloxan induced type 2 diabetes mellitus in wistar albino rats

INTRODUCTION Diabetes mellitus is a common metabolic and endocrine disorder, characterized by chronic hyperglycemia and disturbance of carbohydrate, fat and protein metabolism associated with absolute or relative defi cient of insulin secretion or insulin action [1]. It is a metabolic disorder principally characterized by chronic and persistent hyperglycemia [2]. It is well known that the incidence of diabetes mellitus is high all over the world, especially in Asia. According to the World Health Organization (WHO) projections in 2005, the 30 million to 33 million diabetes in India will go up to 40 million by 2010 and 74 million by 2025. WHO has issued a warning that India will be the diabetic capital of the world [3]. Diff erent types of oral hypoglycemic agents such as biguanides and sulphonyl urea are available along with insulin for the treatment of diabetes mellitus (4). But side eff ects were associated with their uses [5, 6]. Th ere is a growing interest in herbal remedies because of their eff ectiveness, minimal side eff ects in clinical experience and relatively low costs. Herbal drugs or their extracts are prescribed widely, even when their biological active compounds are unknown. Even WHO approves the use of plant drugs for diff erent diseases, including diabetes mellitus. Ethno botanical information indicates that more than 800 plants are used as traditional remedies for the treatment of diabetes [7]. Bauhinia tomentosa L. is a well known, traditional plant used in folklore medicine in tropical regions around the world and especially in greater parts of India. Th ere are about 600 species of Bauhinia L. in the tropical regions [8]. Bauhinia tomentosa is a fast-growing plant that grows up to 4m in height. Leaves are divided into two lobes, light green in colour, with a leathery texture. Infusion of fresh fl owers and barks were used for dysentry. Decoction of root bark was used for liver problems and leaves were externally applied to the forehead for fevers. Large number of Bauhinia species were analysed for their antidiabetic eff ect but the antidiabetic eff ect of B.tomentosa is scarse. So this study aimed in fi nding the antidiabetic potential of B.tomentosa. MATERIALS AND METHODS Plant material and extraction Bauhinia tomentosa leaves were collected from a local farm and authenticated by Dr.G.V.S.Moorthy, Botanical Survey of India, Tamilnadu Agricultural University Campus, Coimbatore. Th e Voucher No is BSI/SRC/73/5/23/09-10/Tech.723 and the specimen was deposited in the department herbarium. After washing with water the leaves were dried at 250C for 10 days in the absence of sunlight and powdered well using a mixer. Th en they were weighed and kept in an airtight container and stored in refrigerator until future use.