Abstract:
The antidiabetic effect of methanolic leaf extract of Vernonia amygdalina (VAM) was
investigated in normal and streptozotocin-induced diabetic rats. Twenty-five (25) albino male wistar rats were used for this study. They were divided into five groups of 5 rats per group.
Group 2-5 rats were induced intraperitoneally with 45 mg/kg body weight streptozotocin dissolved in citrate buffer (0.1 M pH 4.5) on day 1 and monitored for 3 days. On day 4, group 3 was administered Metformin orally while groups 4 and 5 were orally administered 150 and 300 mg/kg body weight respectively daily for 7 days. On the 12th day all rats were sacrificed
by cervical dislocation and specimens were collected. The results of analysis showed that
treatment with VAM after diabetic inducement significantly reduced the blood glucose
concentration in groups 4 and 5. HDL and LDL was significantly (P˂0.05) reduced in
metformin and STZ treated groups compared to the normal control groups. CHOL, TRIG and VLDL improved toward normal level after treatment with VAM in rats except the group treated with STZ+ 150mg of VAM that was high compared to the control group.
Phytochemical and gas chromatography-mass spectrometry (GC-MS) analysis was carried out on the methanolic extract. Phytochemicals such as Alkaloids, carbohydrate, protein, fats and oil, terpenoids, phenol, flavonoid, tannin, glycoside, phytosterol, polyphenol and saponin were present while anthraquinone was absent. Hexadecanoic acid, methyl ester (16.3%), Hexadecanoic acid, methyl ester (14.1%), 9, 12-Octadecadienoic acid (Z, Z)-, methyl ester
(11.8%), 9, 12-Octadecadienoic acid (11.9%), Phytol (10.5%) are the major bioactive
compounds by GC-MS.
Based on this study, it can be concluded that V. amygdalina methanolic leaf extract possesses phytochemical components that can induce changes in lipids concentrations and also act as hypoglycaemic agents. This further confirmed the reason for using the plant as therapy for diabetes mellitus.
