ABSTRACT
Calliandra surinamensis seed was crushed and analyzed for proximate and mineral composition (K, Na, Ca, Mg, Se, Fe, Cu and Zn), amino acid and the fatty acid profile, heavy metals; mercury (Hg), Lead (Pb), Arsenic (As) and other essential minerals such as Selenium (Se), Iron (Fe), Copper (Cu) and Zinc (Zn). The seed was also analyzed for vitamin content (water and fat soluble vitamins), anti-nutrients; phytic acid, tannins, lectins and oxalic acid. The toxicology of the seed on some selected organs was carried out to assess the toxicity of the seed. The result of the proximate analysis showed the % moisture content (12.81 ± 0.03), % crude protein (3.15 ± 0.70), % ash (2.62 ± 0.20), % crude fat (4.74 ± 0.17), % crude fibre (3.68 ± 0.19) and % carbohydrate content (78.65 ± 0.07). The proximate analysis indicated that the seed was a potential source of food nutrients. Essential mineral analysis (mg/kg) showed that; Ca (36.92 ± 0.55) > Mg (27.50 ± 0.61) > K (13.72 ± 1.09) > Na (9.50 ± 1.53) > P (1.79± 0.07). hence good source of macrominerals. The sodium to potassium ratio (Na/K 0.69) was within the range (Na/K ≤1.0) recommended by World Health Organization (WHO) for health vitality. The molar ratio intake of Na/K ≤ 1.0 is considered beneficial for health and a best balance of Na and K intake prevents cardiovascular diseases and all-cause of mortality. Microminerals analyzed (mg/kg) revealed that Fe (0.78 ± 1.29) > Zn (0.49 ± 0.10) > Se (0.28 ± 0.11) > Cu (0.09 ± 0.08) implying that the seed was a rich source of minerals. Toxic elements were also found present with Pb (0.07 ± 0.01mg/l) >As (0.07 ± 0.01mg/l) > Hg (0.02 ± 0.001mg/l). The results for the toxic elements were all below WHO permissible values. Amino acid analyzed (mg/kg) revealed leucine (7.25) > methionine (6.04) > lysine (4.96) isoleucine (4.90) > threonine (2.41) > valine (2.24) phenylalanine (0.82) tryptophan (0.27) histidine (0.02) showing that the seed has great value as it contains all the nine essential amino acids. Other amino acids also found were; Alanine (3.30) Senine (0.84) Proline (0.18), Glutamate (0.05), Tyrosine (15.34), Aspartate (6.28), Arginine (0.19), Glycine (2.74) and Cystenine (2.73). The results from fatty acid evaluation (%) showed that Oleic acid (34.86) > Linolenic acid (21.68) > linoleic acid (14.00) were the most concentrated fatty acids. Stearic acid (9.78) > Cervonic acid (9.39) > Lauric acid (4.76) > Paullinic acid (2.25) > Palmitic acid (1.47) > Myriststic acid (1.22)> Eicosapetaenoic acid (0.55) > Tetracosanolpetanoic acid (0.04) were present in smaller quantities. The seed, like most legumes contained high proportion of unsaturated fatty acid (Oleic acid, Linolenic acid (omega 3) and linoleic acid (omega 6) which are essential fatty acids. The result of the Vitamin contents (mg/kg) revealed B1 (I.067 ± 0.04), B2 (I.389 ± 0.01), B3 (2.48 ± 0.22), B5 (608.8 ± 129.0), B6 (1.336 ±0.07), B7 (1.23 ± 0.01), B9 (1.22 ± 0.11), B12 (0.63 ± 0.07), C (137. 4 ± 26.20), A (5.04 ± 0.39), D (2.57 ± 0.42), E (2.14 XVIII ± 0.14) and K (0.52 ± 0.03). Results from antinutritional analysis (mg/kg) showed that tannins were the most abundant antinutrient in the seed followed by lectin, phytic acid and oxalic acid: T (26.33) > L (9.17) > P (8.77) > O (1.89). This indicated that the seed was a good source of antioxidants especially with the high value of tannin, a powerful antioxidant and will be helpful in maintaining good health. An acute toxicity study using Lork’s and sub-chronic toxicity methods were carried out following the Organization of Economic Cooperative and Development (OECD) guidelines with testing chemicals 423 and 407. In the acute toxicity study, the first phase of the method, twelve (12) mice and single dose of 10, 100 and 1000 mg/kg body weight of C. surinamensis seed extract were administered orally. In the second phase, twelve (12) mice were used and single dose of 1200, 1600, 2900 and 5000 mg/kg body weight of the methanolic seed extract respectively was administered orally with repeated doses of 200, 400 and 800 mg/kg for 28 days. The hematological indices as well as histopathological analysis of the organs; heart, liver, lung, stomach, kidney and spleen were evaluated and compared to normal group after sacrificing three rats from each group.. The hematological indices revealed no significant change in red blood cells and other hematological parameters. Heart; there was vasodialation of the blood vessels resulting in increase in blood flow. Liver: there were desirable morphological vasoactive changes of dilatation and active congestion in the organ across all the concentrations in a dose dependent pattern with the highest dose (800 mg/kg) inducing the most observable changes. There was an activation of the sinusoidal kupffer cells, which signified a boost to the local immune system of the liver. The nucleoli in the hepatocyte nuclei were remarkably conspicuous, implying increase in the production of ribonucleic acid (RNA) that are deployed in protein synthesis. In the lungs, there was obvious activation of the bronchiole giving rise to bronchiolar alveolar lymphoid aggregate. Stomach; in the stomach, there was normal muscularis propria, submucosal and mucosal architecture. Kidney; the oral administration of methanolic extract of the seed for 28 days did not produce significant alteration in the renal function indices. The histological examination of the rats indicated normal glumeruli and regular renal tubules. In the Spleen; there was increased sequestration of the red blood cells and activated lymphoid follicles (immune system). .The average organ weight of the group tested seed extract and the control showed statistically no significant difference (P>0.05). Therefore, Calliandra surinamensis seed did not showed any toxic effect on the organ functions of the wistar rats and as a result, could be an important source of nutrition to the livestock feed industry.
