COMPARATIVE STUDY OF THE PHYSICOCHEMICAL PROFILE OF THEVETIA PERUVIANA AND RICINUS COMMUNIS SEEDS

This paper assessed the comparative study of the physicochemical profile of yellow oleander and castor oil seeds. The fruits were air dried, cracked to remove the seed; the seeds were pound in a mortar and pestle into paste (cake) in order to weaken or rupture the kernel walls. Fluid from the paste were squeezed out and packaged in airtight sample plastics and stored in the refrigerator at 4 ºC prior to laboratory analysis. The physicochemical properties such as iodine value, moisture content, saponification value, acid value, viscosity, specific gravity and refractive index were determined. At the end of the analysis, Iodine value obtained for both yellow oleander and castor oil seed samples were found to be 94gI2/100g and 86gI2/100g respectively and both values fall within the acceptable AOCS limit. The moisture content in both yellow oleander and Castor oil seed samples were found to be 0.52% and 0.35% respectively. Statistical analysis showed no significant differences (P≤0.005) among the values obtained. The saponification value obtained for yellow oleander and Castor oil seed samples were found to be 193mgKOH/g and 180mgKOH/g respectively and are within the range specified by AOCS. There were significant differences (p≤0.05) among the values obtained. The acid value obtained for both yellow oleander and Castor oil seed samples were found to be 18.46mgKOH/g and 12.66mgKOH/g respectively. Statistical analysis showed significant differences (P≤0.05) among the values obtained.  The value for castor oil exceeds the AOCS limit of 2.0 mgKOH/g. Kinematic viscosity obtained were 7.8mm2/s and 6.9mm2/s for yellow oleander and Castor oil respectively. These are within the range specified by AOCS. Statistical analysis showed no significant differences (P≤0.05) among the values obtained.  Refractive index measured was found to be 1.469 and 1.468 for yellow oleander and castor oil respectively. These are within the range specified by AOCS. Statistical analysis showed no significant differences (P≤0.05) among the values obtained. Specific gravity measured was found to be 0.925 and 0.9166 for yellow oleander and castor oil respectively. These are within the range specified by AOCS. Statistical analysis showed no significant differences (P≤0.05) among the values obtained. The physicochemical profile of the seed samples investigated contains presence of some valuable minerals which suggest that they can be used for industrial purposes such as soap and oil as biodiesel.