THE AFRICAN BAOBAB SEED OIL AND ITS POTENTIAL FOR SOLUBILISING POORLY SOLUBLE DRUGS

Most lipids used in solubilizing poorly soluble drugs are synthetic or semi-synthetic. In this study, the African Baobab seed oil (natural oil) was investigated for its potential in solubilizing poorly soluble drugs in a microemulsion formulation. Oil was extracted from untreated seeds by hydraulic pressing. Physicochemical characteristics of the oil were determined. The solubility of Furosemide, Griseofulvin, Ibuprofen, and Mebendazole was determined in the seed oil, surfactants, and co-surfactants. The miscibility of the oil, surfactants, and co-surfactants was assessed. A ternary phase diagram was developed to determine the microemulsion zone. Formulations of drug incorporated microemulsions were prepared using the seed oil. The microemulsions were characterized by droplet size, pH, transmittance, in-vitro drug release, and stability. The oil from the seeds was golden yellow in appearance. It was free from disease-causing pathogens. Analysis of the oil constants revealed that the oil was good for use as a pharmaceutical excipient. Optimised composition of 15% oil, 75% surfactant and 10% water formed a clear and stable microemulsion which solubilised Furosemide (30 mg/ml), Griseofulvin (30 mg/ml), Ibuprofen (450 mg/ml) and Mebendazole (25 mg/ml). Percentage cumulative drug releases of 68.81 ± 1.21, 68.86 ± 7.16, 77.70 ± 0.68 and 55.64 ± 0.17% for Furosemide, Griseofulvin, Ibuprofen, and Mebendazole, respectively were obtained over a four-hour dissolution study using phosphate buffer pH 6.8, showing a retarded release of the drugs from the microemulsion. The extracted oil is suitable for use in a microemulsion formulation for the solubilization and delivery of poorly soluble drugs.