Anti-diabetic Activity of Stereospermum Colais (Bignoniaceae) Leaf Extracts

Abstract

Stereospermum colais (Bignoniaceae), known as Yellow snake tree in English and Pathiri in Tamil, is used in Ayurvedic system of medicine to treat various ailments includes vomiting, leprosy, fevers, mitigate kapha, itching, diabetes, and clean bad wounds. The coarsely powdered leaves of the plant material were extracted successively with n-hexane, chloroform, ethyl acetate, ethanol in increasing polarity by using Soxhlet’s apparatus and aqueous extract by the maceration process. The Preliminary phytochemical analysis of various extracts and powder revealed the presence of carbohydrates, proteins, amino acids, steroids, glycosides, phenolic compounds, tannins, terpenoids, quinones, furan, gums and mucilage, fats and oil. The various extracts of S.colais were evaluated at a concentration of 50gram/litre using an in vitro method glucose diffusion inhibitory assay to assess the possible effects on glucose diffusion across the gastrointestinal tract and compared to the control conducted in the absence of extracts. The movement of glucose into the external solution was determined by using glucose oxidase peroxide diagnostic kit at a regular intervals. The ethanolic extract showed a significant Glucose Diffusion Retardation Index (GDRI = 1.38 ± 0.005 at 180min), and it proves the traditional claim at this stage. Hence, an in-depth research can be established to identify, isolate and characterize the compound having antidiabetic therapeutic potential.