Zinc content was highest in Moringa oleifera, Adansonia digitata and Cassia tora leaves (25.5 mg/100 g, 22.4 mg/100 g and 20.9 mg/100 g dw, respectively) while the manganese content was comparatively higher in Colocasia esculenta. Microelement content of the leaves varied appreciably.
All the vegetables contained high levels of calcium compared to common vegetables, thus they could be a rich source of this mineral. These values are low compared to those for common Nigerian vegetables but higher than those for other food sources. Amaranthus spinosus and Adansonia digitata leaves contained the highest level of iron (38.4 mg/100 g and 30.6 mg/100 g dw, respectively). Mineral contents appeared to be dependent on the type of vegetables. Six non-conventional leafy vegetables consumed largely by the rural populace of Nigeria were analyzed for mineral composition.
Mineral composition of non-conventional leafy vegetables.
