Investigation of Micro, Macro and Heavy Elements in Some Selected Fruits and Vegetable Seeds to Assess Usefulness as Food Supplement

Abstract

Ten different seed samples were obtained from Owo and Akure markets in Ondo State of Nigeria. They were dried in the oven between a temperature of 100 oC- 105 oC, then pulverized into powder and analysed for (20) twenty elements, of K , Ca, S, Si , P, Fe , Al , W, Mn ,Cu, Mg, Ni, Co, Pb, As, Ti, V, Cr, Rb and Ag using ED-X-ray Fluorescence (XRF) spectrophotometer. The concentration of elements listed above followed a decreasing order of K >Ca> S > Si > P> Fe > Al > W>Mn>Cu > Mg > Ni > Co >Pb> As > Ti > V > Cr >Rb> Ag. Five (5) macro elements, K, Ca, Mg, P, and S were detected in all the seeds samples at varying concentrations, also five (5) micro elements Zn, Cu, Fe, Si and Mn were detected in all the seeds samples also at varying concentrations. And eight (8) heavy elements, Cr, Co, Ni, As, Ag, Au, W and Pb were present in some of the seed samples. The following seeds were rich in Potassium (K), P. dulcis, S. cannum, C. lanatus, C. papaya, C. mannii and C. limon. Phosphorus, (P) was present in concentration ranged between 0.2-1.6% and the following seeds:C.lanatus, C.manni, C. olitorius and P. dulciswere rich in phosphorus. Calcium (Ca) was detected between 0.1- 15.0% and the following seeds are rich in calcium: C. olitorius, C. Lanatus, C. reticulata and P. dulcis. Magnesium, (Mg) concentrations ranged between 0.2-0.4% and P. dulcis, C. Lanatus, C. manni and C. olitoriuswere rich in magnesium. Sulphur (S), concentrations ranged between 1.72-4.5% and C. lanatus, C. sativus, C. olitorus, C. papaya, p. dulcis, and C. manniwere rich in sulphur. Micro-elements such as Fe (0.08-1.17%) were present in P. dulcis, P. lanatus, C. manni, C. olitorus, C. limon, S. canum, T. occidentalis and C. reticulate seeds. Zinc (Zn) was present in the range between 0.09-0.26% in seeds of P. dulcis, P. lanatus, C. manni, C. olitorus, C. limon and S. canum. For heavy metals, Lead (Pb) was detected in C. papaya with a concentration of 0.056% while Lead was present in other seed samples at very low concentration, 0.001-0.004%.