COMPARATIVE PHYTOCHEMICAL, PROXIMATE, AND in vitro ANTIHYPERGLYCEMIC ANALYSES OF THE ROOT BARK EXTRACTS OF Nauclea latifolia Smith AND THE STEM BARK EXTRACTS OF Azadirachta indica A. Juss.

Abstract

Diabetes Mellitus is a systemic metabolic disorder caused by relative or absolute insulin secretion deficiency or resistance, characterized by hyperglycemia. It has affected 5% of the world’s population and accounts for about 10 % of total health care expenditure in many countries. The present investigation was carried out to explore the proximate, phytochemical compositions and antihyperglycemic potentials of Nauclea latifolia Smith and Azadirachta indica A. Juss. The selected plant parts were subjected to solvent extraction using three solvents of varying polarity (hexane, ethyl acetate, and methanol), followed by phytochemical screening. Some of the extracts were analyzed for their antihyperglycemic activity using in vitro assays such as α-amylase inhibition assay and glucose uptake by yeast cells. The phytochemical analysis showed the presence of saponins, flavonoids, alkaloids, tannins, steroids, terpenoids, and glycosides in various amounts. The proximate composition revealed the following: moisture content (9.00 %); ash content (5.33 – 8.00 %), crude fiber (23.75 – 33.75 %); oil content (12.50 – 12.86 %) and carbohydrate (6.00 – 31.49 %). The results of the assays suggest that the methanol extract of the stem bark of Azadirachta indica A. Juss showed the highest value of inhibition (87.61 %) at 0.1 mg/ml concentration when compared to acarbose (56.0 %) used as the control/standard drug. It is noteworthy that various levels of inhibition are not concentration-dependent. The percent glucose uptake of methanol extract of Azadirachta indica A. Juss was recorded highest (49.49 %) at 1.0 mg/ml. This study’s finding favors the use of these medicinal plants for the management of diabetes which might be due to the presence of bioactive phytoconstituents inherent in them.