ISOLATION OF CACCIGENIN AND INVESTIGATION OF ANTI-DIABETIC PROPERTIES OF TROPICAL ALMOND (Terminalia schimperiana) ROOT BARK EXTRACTS ON ALBINO RATS

Abstract

The research tests for anti-diabetic activities of the crude extracts of Terminalia schimperiana root bark, then isolated and characterize active ingredients therein responsible for the bioactivity. Ethylacetate /methanol 1:1 root bark extract was screened for anti-diabetic activity based on folklore. The extract gave anti-diabetic activity comparable to the positive control glibenclimide in alloxan induced diabetes mellitus rats. The study evaluated the ethylacetate/ methanol extract for anti-hyperglycaemic activities and effects on the serum lipid profile in rats. In a dose response study over a six-hour period, 200 mg/kg and 100 mg/kg oral dose of the extract gave the best anti-diabetic activities and was employed in the study. Following oral daily treatment for fourteen days with T. schimperiana extract at 100 mg/kg and 200 mg/kg body weight, the serum total cholesterol (TC) levels, LDL, triglycerides and HDL were significantly lower (p <0.05) than those of alloxan induced untreated groups. Chromatographic separation of the hexane/ethylacetate extract yielded three chemical isolates which were characterized using 1-D and 2-D NMR spectral to be Caccigenin. It showed six 3H-singlets for the six methyl groups with characteristic signals at δ 1.24, 0.89, 0.67, 1.24, 0.97 and 0.96. Based on this, Terminalia schimperiana have potentials that can be explored in the search for anti-diabetic drug from nature. Key words: Terminalia schimperiana, Bioactivity, Anti-hyperglycaemic activity, Chromatographic separation and Characterization.