Studies on the Nutritional, Minerals, Mineral Ratio, Anti-nutritional, Molar Ratio and Antioxidant Compositions of Four Selected Leafy Wild Vegetables in Ado-Ekiti, Ekiti State, Nigeria

Abstract

The study investigated the nutritional, mineral Anti-nutritional factors, molar ratios and antioxidants compositions in the leaves of four selected wild edible vegetables (Piper guinensis, Piper umbelatum, Celosia argentia and Jatropha tajorensis) collected in Ado Ekiti, Ekiti State, Nigeria. The proximate, minerals and anti-nutrient compositions of the samples were determined using standard procedures. Also antioxidant activity of the samples were detected using standard assays such as 1, 1, diphenyl-2-2 picrylhydrazyl (DDPH) and Ferric Reducing Antioxidant Potential (FRAP).The mineral ratio, molar ratio and Mineral Safety Index were calculated from mineral results. The results of the proximate compositions for the four wild vegetables for moisture content, ash, crude fat, crude fiber, crude protein and carbohydrate ranged from 11.16 - 12.15%, 2.76-4.03%, 4.07 -7.31%, 13.33-16.73%, 7.36 – 10.09%, and 52.09 -58.22% respectively,. The results of the mineral composition revealed high content of K, moderate content of Ca, P, and low contents of Mg, Fe, Zn, Cu and very low concentrations of Pb and Ni. Cd was absent in all the samples investigated. Zn/Cu and Fe/Cu ratios indicated low copper load. Antinutrients factors in the vegetable were low with the exception of phytate which can be reduced to non-toxic level through boiling or cooking. The calculated mole ratio for [Phy][Zn], [Ca]/[Phy], [Phy]/[Fe] and [Ca][Phy]/[Zn] conformed with the standard values. The results of the antioxidant properties showed that the wild vegetables are good natural antioxidant sources. The assessment of the vegetables showed that they are rich sources of crude protein, crude fiber and carbohydrate with high energy calories. The mineral ratios and mineral safety index suggested that the minerals could not pose any mineral load to human body. Hence, the vegetables could be explored as supplement diet for man. The vegetables could provide the needed nutrition health benefit and also help in addressing the problem of food security in Nigeria.