Levels of antinutritional factors in some wild edible fruits of Northern Nigeria

Sixteen wild fruits commonly consumed in northern Nigeria were assessed chemically for the presence of oxalate, phytate, saponin, and tannin. The highest level of oxalate was found in Zizyphus spinachristi, Zizyphus mauritiana and Balanite aegyptiaca (16.20±2.12%, 15.50±1.50% and 14.50±2.08%, respectively). Phytate was highest in Sclerocarya birrea (3.56±0.54%) and Haematostaphis barteri (3.30±0.10%). B. aegyptiaca, Detarium microcarpum and Parkia biglobosa had the highest saponin values of 16.01±0.02, 12.10±0.05 and 12.23±0.46% respectively. While tannin was highest in B. aegyptiaca (7.40±0.14%), closely followed by Hyphaena thebaica (6.39±0.5%) and Borassus aethiopum (5.90±0.13%). Though these antinutrients can interfere with nutrients utilization when in high concentration, the values obtained for the fruits analysed were not up to the toxic levels of the antinutrients. Fruits such as Vittaleria paradoxum, Adansonia digitata, Diospyros mespiliformis Phoenix dactylifera and young shoot of Bor. aethiopum are highly recommended for consumption as they contain low amount of the antinutrients analysed.