Abstract
Background: Newbouldia laevis is used in West African region to treat many disease conditions including Diabetes mellitus (DM). When we administered Newbouldia laevis leaves extract (NLE) orally in diabetic albino rats, it showed some antidiabetic and cardiovascular protective effects like decreasing the fasting blood sugar (FBS) and bad lipids, as well as increasing the good lipids. These effects are beneficial to health and associated with unsaturated fatty acids. Here we isolate the active compound responsible for these activities in NLE through a bioassay-guided process and Nuclear Magnetic Resonance (NMR) with Gas Chromatography-Mass Spectroscopy (GC-MS) NMR/ GC-MS were used to characterized and identify the compound.
Methods: Newbouldia laevis leaves (NLE) were extracted in 80 % methanol. Diabetes Mellitus was induced in Twenty five overnight-fasted albino rats by single intraperitoneal administration of 150 mg/kg Alloxan monohydrate (Sigma) and randomly divided into 5 groups (N=5) and treated with 10 ml/kg distilled water, 2 mg/kg glibenclamide, 62.5, 125.0 and 250. 0 mg/kg NLE respectively, for 21 days orally and blood was collected on day 21 for FBS, serum biochemistry, lipid peroxidation etc. Chorum and Thin layer Chromatography were used to fractionate the extract and activity-guided isolation was carried out. Nuclear Magnetic Resonance (NMR) with Gas Chromatography-Mass Spectroscopy (GC-MS) were used for characterization and identification of the active compound.
Results: Newbouldia laevis caused dose-dependent decrease in Fasting blood sugar (FBS) and all the bad lipids as well as reduced the atherogenic and coronary risk indices, but increased the good lipids. Bioassay-guided isolation showed consistent decrease in FBS comparable to glibenclamide. NMR,GC-MS revealed the active compound to be a long chain polyunsaturated fatty acid, with a chemical formula C24H38O2 and a molecular weight of 358.56 g.
Conclusions: Newbouldia laevis leaves contain a long chain polyunsaturated fatty acid with a chemical formula C24H38O2 and a molecular weight of 358.56 g that has antidiabetic action and other health benefits and its use in West Africa for the treatment of DM and other health conditions has pharmacological basis. We wish to estabilish the mechanism of action of the compound as a way forward.
