Physicochemical Studies on Oils from Five Selected Nigerian Plant Seeds

Oils were extracted from four underutilized seeds of the Nigerian plants Chrysophylum albidum, Dacryoides edulis, Landolphia owariensis and Napoleona imperialis using n-hexane and their physicochemical properties compared with oils from seeds of Elaeis guinensis. Percent oil yield were 12.00, 15.80, 6.40 and 8.00 for C. albidum D. edulis, L. owariensis and N. imperialis respectively while the value for E. guinensis seed is 28.00. The four seed oil were odourless and at room temperature liquids as against E. guinensis seed oil that were semi-solid under the same condition. Specific gravity of the seed oils ranged from 0.82-0.94 while peroxide value for all the oil extracts except that from D. edulis seed were less than three. Saponification values were as low as 42.40 in L. owariensis and as high as 246.60 in E. guinensis seed oils. Iodine values were between 15.10 and 45.00 in the extracts. These results suggest that C. albidum and D. edulis seeds may be viable sources of oil going by their oil yield. However the studied characteristics of all oils extracts in most cases compared favourably with E. guinensis seed oil which is presently used for many domestic and industrial purposes in Nigeria.