CHEMICAL ANALYSIS OF THE SEED OIL OF CANAVALIA ENSIFORMIS LINN. FOR NUTRITIONAL AND INDUSTRIAL QUALITIES

Abstract

The extensive demand for oils by man for consumption and industrial applications has led to an increasing search for oils from non-conventional sources to augment the available ones. Thus, the seed oil of Canavalia ensiformis Linn., a leguminous plant abundantly found in South-western Nigeria was extracted and analysed for its nutritional and industrial applications. Phytochemical screening and proximate analysis of the seeds along with physicochemical parameters of the oil using standard procedures were done. Different weights of the powdered seeds were extracted using a soxh let extractor with four solvents- n-hexane, chloroform, petroleum ether and ethanol. The fatty acid composition of the oil was characterized by Gas chromatography-Mass spectrometry (GC-MS). Canavalia ensiformis seed contained saponins, anthracene derivatives, phenols, tannins, sapogenin and reducing sugar. The proximate analysis gave 1.50±0.84, 25.51±0.21, 2.10±0.23, 3.05±0.92, 56.94±1.96, 10.90±1.11 for moisture content, protein, ash content, crude fibre, carbohydrate, and oil extracts respectively. The physicochemical parameters of the oil were: pH-4.69, specific gravity0.89±0.01, acid value-6.2, saponification value-203.3 mg KOH/g, free fatty acid-3.1, peroxide value18.50 and iodine value-61.0 g of I/100 g oil, while the oil is miscible with petroleum ether. The fatty 2 acid compositions were 11-octadecenoic acid (43.86%) 9-octadecenoic acid (27.49%), hexadecanoic acid (17.07%), cis-11-eicosenoic acid (4.32%), ethyl cis-9-octadecenoate (3.80%) and methyl octadecanoate (3.46%). The presence of 75.67% monoenoic acids in its composition, high saponification value, good foaming and emulsion properties makes the oil useful as an emollient, excipient in pharmaceuticals and solubilizing agents in aerosol products and also of great importance in soap and cosmetics industries.