Determination of the concentrations of Cu, Zn and Fe in five selected leafy vegetables used as relish in Kano State, Nigeria

In tropical Africa, leafy vegetables are traditionally cooked and eaten as relish together with a starchy staple food. Vegetables usually differ according to their type and nutritive values. In this research the Cu, Zn and Fe contents of five leafy vegetables (African spinach (Amaranthus hybridus), baobab (Adansonia digitata), bitter-leaf (Vernonia amygdalina), jute (Corchorus olitorius) and sesame leaf (Sesamum indicum)) were investigated using Atomic Absorption Spectrophotometer and the results were analyzed. The levels of Cu in the leaves of African spinach, baobab, bitter-leaf, sesame leaf and jute were averagely found be 1.60 mg/Kg, 1.60 mg/Kg, 1.90 mg/Kg, 2.00 mg/Kg and 1.70 mg/Kg respectively; while the Zn levels were averagely found be 1.20 mg/Kg, 0.70 mg/Kg, 0.50 mg/Kg, 1.60 mg/Kg and 0.90 mg/Kg respectively; and the Fe levels were averagely found be 246.12 mg/Kg, 170.23 mg/Kg, 218.10 mg/Kg, 166.76 mg/Kg and 272.80 mg/Kg respectively. The results were then compared to, and found to be within the FAO/WHO recommended values for the daily human intake. This indicates that these vegetables could be good sources and supplements for the elements analyzed.