Carica papaya is a fruit known for it great economic values in tropical Africa due to it diverse industrial, medicinal and nutritional benefits. In this study, oil was extracted from dried powdered Carica papaya seeds using n-hexane as extraction solvent and the percentage oil yield determined. The physiochemical characterization of C. papaya seed oil extract was investigated using Association of Official Analytical Chemists (AOAC) standard procedures. Acute toxicity test was carried out to determine the toxicity of the C. papaya seed oil (CPSO). The rats were randomly divided into four groups with five rats per group. Groups B, C and D were given 200, 400 and 800mg/kg body weight of the seed oil extract thrice in a week for 28 days while group A rats were not administered with the oil. The results obtained from the physical properties of the CPSO include; oil yield (30.31Â±2.38%), colour (golden yellow), specific gravity (0.9162Â±0.012), refractive index (1.468Â±0.22), viscosity (22.45Â±2.00 mms-1), melting point (42.30Â±3.0Â°C), smoke point (212.13Â±9.0 Â°C) and flash point (274.74Â±12 Â°C). The chemical properties indicate the presence of acid value (2.848Â± 0.28%), free fatty acids (1.29Â±0.16%), saponification value (mgKOH/g) (192.06Â±1.62), iodine value (70.78Â±1.69 gI2/100g) and peroxide value (5.079Â±0.079 meq/kg). The fatty acid profile of CPSO shows that it contains: oleic acid (73.36Â±1.07%), palmitic acid (14.36Â±0.96%), stearic acid (5.09Â±0.5%) and linoleic acid (4.56Â±0.20%). The total composition of unsaturated fatty acids and saturated fatty acids in CPSO were 79.52% and 20.48% respectively. The oil extracted from C. papaya seeds exhibited viable potentials for biodiesel feedstock based on the results of the physicochemical parameters of the oil extract. The biochemical parameters show that the oil is hematotoxic, it causes significant (P<0.05) increase in total cholesterol (TC), triglyceride (TG) and low density lipoprotein-cholesterol (LDL-C) values. The high density lipoprotein-cholesterol (HDL-C) and catalase did not show any significant (P>0.05) difference among all groups. The oil has slight effect on the kidney and the heart architecture.
Keywords: Biodiesel, biochemical parameters, Carica papaya seed oil, histopathology