EVALUATION OF CHEMICAL COMPOSITION OF THE SEED AND EXTRACTED OIL OF (Canarium schweinfurthii bursaraceae) PURPLE CANARY TREE

Abstract

The matured disease-free atili (Canarium schweinfurthii) seeds and their extracted oils (crude and refined) were evaluated for their chemical composition using standard methods. The proximate composition (%) of the seed pulp showed moisture content (30.21), ash (1.86), fat (34.83), fibre (3.19), protein (12.67) and carbohydrate (17.24). Mineral contents (mg/100g) of the seed indicated; calcium (32.0), phosphorous (16.8), iron (5.6), sodium (15.3), potassium (21.4), magnesium (24.0), copper (2.1), manganese (0.3) and zinc (6.3), lead and cadmium were not detected. Preliminary phytochemical screening of the plant extracts showed the presence of phytochemical constituents such as tannin, resin, saponins, flavonoids, terpenoids, steroids, alkaloids, protein, glycosides, carbohydrates and fixed fat & oils in ethanol extract with highest concentrations followed by water extracts. Antioxidant potential of various extracts of n-hexane, acetone, ethanol and water respectively were; total phenol (416.14, 412.03, 620.31 and 598.47) g GAE/100g, total flavonoids (1.18, 1.83, 3.56 and 2.71) mg RE/g, Ferric reducing property (106.28, 232.03, 258.96 and 284.11), 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging (13.61, 17.28, 48.15 and 32.27), vitamin C (32.85, 31.32, 34.21 and 45.21) mg/100g and vitamin E (487.20, 451.40, 338.0 and 338.0) ppm. Physicochemical properties of crude and refined oils respectively were colour (dark green and greenish yellow), specific gravity (0.9516 and 0.8621), refractive index (1.4012 and1.3034), acid value (1.14 and 0.64) mgKOH/g, free fatty acid (0.96 and 0.34), peroxide value (1.08 and 0.71) meq/kg, iodine value (96.51 and 117.29), saponification value (148.3 and 126.8)mgKOH/kg, unsaponifiable matter (1.73 and 1.21) %, freezing point (-7.5 and 13.0) oC, melting point (43.0 and 39.0) oC, smoke point (187 and 203) oC, flash point (283 and 317) oC and fire point (345 and 358) oC respectively. Amino acid profile of seed pulp showed concentration of total amino acid of (83.01 g/100g protein), total essential amino acids (45.15 g/100g protein) and total non-essential amino acids (37.86 g/100g protein). The fatty acid composition of crude and refined oils respectively are; stearic (10.765 and 11.481) %, myristic (2.612 and 2.963) %, palmitic (0.358 and 0.574) %, capric (0.013 and 0.024) % and total saturated (13.748 and 15.042) %. The unsaturated are; oleic (31.621 and 35.386) %, palmitoleic (0.053 and 0.142) %, erudic (1.017 and 1.084) %, linoleic (23.724 and 28.612) % and linolenic (0.638 and 0.086) %, total unsaturated (57.053 and 66.370) %. The total fatty acid determined in crude and refined oils are (70.801 and 81.412) % and total undetected was 29.199 and 18.588 % respectively. The study concluded that the seed pulp of canarium is a good source of fat, protein and very rich in nutritionally valuable minerals, antioxidants as well as essential and non-essential amino acids. The extracted oil of canarium seed is better consumed in refined form for its better physicochemical properties and unsaturated fatty acid composition. Therefore, the seed will be useful in food and feed industries.