EXTRACTION OF VARIOUS EXTRACTS OF LEAVES OF ALLAMANDA CATHARTICA LINN. & ASSESSMENT OF THEIR HYPOGLYCEMIC POTENTIAL

Dr. Meenakshi Fartyal*, Padma Kumar

Laboratory of Plant Tissue Culture and Secondary Metabolites, Department of Botany, University of Rajasthan, Jaipur, Rajasthan, India.

ABSTRACT

Background: Diabetes mellitus describes a metabolic disorder which results in increased blood glucose levels and disturbances of metabolism resulting from defects in insulin secretion, insulin action or both. Numbers of diabetic patients are increasing globally at large level. Ornamental plants of family Apocynaceae consists of several important medicinal plants with wide range of biological activities, interesting phytochemical constituents & have been traditionally used for the treatment of different ailments. Objective: Extraction & evaluation of the antidiabetic activity of extracts from leaves of Allamanda cathartica (Apocynaceae) Linn. Methods: Leaves of A. cathartica Linn. were collected, dried and extracted by using well established methods for alkaloids, flavonoids, steroids and crude extracts in polar and non-polar solvents. Evaluation of their antidiabetic activity was done with salivary alpha amylase and starch as substrate using chromogenic DNSA (2,4- Di nitro Salicylic Acid) method & Starch iodine method. All experiments were performed in 3 different sets each in triplicates. The data are expressed as 536 Journal of Medical Pharmaceutical and Allied Sciences (December 535-546) mean ± SEM (standard error of the mean). Results: The highest inhibition (26.29±0.44%) was obtained at concentration of 1.5 mg/ml of methanolic extract of leaves with an IC50 value of 5.098 g/ml. Steroid extracts were also found to have high inhibitory potential with low IC50 value. All other tested extracts (not alkaloids) were also showed good alpha amylase inhibition activity. Conclusion: Thus, all the tested leaf extracts might be effective in lowering the postprandial hyperglycemia by inhibiting salivary alpha amylase enzyme.

Keywords: Antidiabetic activity, Salivary alpha amylase, DNSA, Starch, Iodine, Phosphate Buffer.