Lipospheres: A Potential Delivery System of Herbal Extract for the Treatment of Diabetes Mellitus

In view of the wide spread use of herbal formulations and its proven efficacy, there is need for standardization and quality control. Gongronema latifolium is widely used in the folk medicine in the treatment of diabetes, hence the need for an effective delivery system for this natural plant. The methanolic extract of Gongronema latifolium leaves (1, 3 and 5 %) were formulated into lipospheres by melt homogenization using lipid matrix consisting of mixture of goat fat and Phospholipon® 90H (1:2). The lipospheres were characterized by analyzing the encapsulation efficiency(EE), pH, particle size and morphology. The in vivo antidiabetic properties were studied in alloxan induced diabetic Wistar rats. The results showed spherical lipospheres within µm limit, stable pH over 30 days and EE% of 86, 89 and 90 % for batches A, B and C containing 1, 3 and 5 % Gongronema latifolium extract. Gongronema latifolium-loaded lipospheres (100 mg/kg) had 55.2 and 70.6 % reduction in blood glucose of the diabetic rats at 8 and 12 h respectively, while, the rats that received glibenclamide (0.2 mg/kg) had 38.4 and 53.4 % reduction in blood glucose at 8 and 12 h. Gongronema latifolium-loaded lipospheres had significantly higher antidiabetic properties than (p < 0.05) the reference drug at concentrations used.