Genotypic Variation of Mineral Elements and Phytate Levels of Thirty Cowpeas (Vigna unguiculata L. Walp.) Varieties Cultivated in Burkina Faso

Abstract

Cowpea is consumed as a staple food in many developing countries. The present study was undertaken to determine the variation in mineral elements and phytate concentrations in 30 cowpeas seeds varieties consumed in Burkina Faso. The composition of the thirty cowpeas seeds in total mineral varies from 5.08 % ± 0.00 to 3.55 % ± 0.08. The genotype CR06-07 showed the high content of total mineral (ashes) and the genotype Kondesyoungo local, the low content of ashes. IT81D-994 showed the high content of iron (7.07 ± 0.057 mg/100g of seeds dw), zinc (4.42 ± 0.012 mg/100 g of seeds dw), magnesium (239.80 ± 1.192 mg/100 g of seeds dw), calcium (123.39 ± 2.31 mg /100 g of seeds dw) and potassium (1201.97 ± 25.66 mg/100 g of seeds dw). Na and Se levels in the seeds showed about 4.5-fold and 7.6-fold variations between the cowpeas varieties. The genotype komcallé showed the high content of sodium (5.45 ± 0.20 mg/100 g of seeds dw) and the genotype KVx 414-22-2 had the high content of selenium (0.006 ± 0.0002 mg/100 g of seeds dw). The phytate content of the cowpeas genotypes varied from 555.61 ± 7.48 for TVU 14676 to 13.50 ± 1.14 mg/100 g of seeds dw for KVx 30-309-6G. The [Phy]/[Fe], [Phy]/[Zn], [Phy]/[Ca] and [Phy] x [Ca]/[Zn] ratios showed that the phytate content might compromise the Fe, Zn and Ca bioavailability in some cowpeas varieties. This study indicates that the cowpeas varieties might be considered as mineral source suitable for animal and human consumption.