Proximate and mineral composition of six commercially important fishes in Obueyinomo River, Benin City, Edo State
This study was conducted from May 2015 to April 2016 on the proximate and mineral composition of six species of fish from Obueyinomo River in Edo State, Nigeria. The six (6) species are M. electricus, C. gariepinus, T. zilli, A. monkei, P. obscura, P. africana. Biochemical assay of moisture, ash, crude protein, crude fiber, lipids, carbohydrates and the elements (macronutrients) Na, k, Ca, Mg, P and (micronutrients) Fe, Mn, Zn, Pb and Cd of the fishes were done in the laboratory. The results revealed the presence of moisture content ranging from 56.50 – 69.0%, fiber 0.46 – 2.70%, protein 15.2 – 24.8%, lipid 8.73 – 12.09%, ash 1.07 – 3.50%, carbohydrate 2.56 – 12.68%. Macro-nutrients included calcium (12.01-41.39mg/kg), sodium (22.48-58.35mg/kg), potassium (47.50-85.36mg/kg), magnesium (9.45-45.04mg/kg), potassium (1.89-39.6mg/kg), Micro - nutrients are iron (78.88-122.45mg/kg), manganese (25.03-61.84mg/kg), zinc (3.05-6.93mg/kg). Lead was in trace amount (0.35 – 0.49mg/kg) but cadmium was not detected in all the fishes sampled. Levels of heavy metals are below WHO limits. The six fishes studied are rich in protein, lipids, fibre, carbohydrate and are good sources of minerals to meet desired human nutritional requirement.
Keywords: fish species, proximate composition, mineral elements, heavy metals