Estimation of Heavy Metals, Essential Trace Elements and Anti-Nutritional Factors in Leaves and Stems from <i>Moringa oleifera</i>

Abstract

This study was conducted to estimate the concentrations of 8 trace elements including (Mn, Fe, Cu, Zn, Ni, Ar, Cr, and Pb) and 4 anti-nutritional factors including (saponins, oxalates, phytate, and cyanogenic glycosides) in leaves and stems from Moringa oleifera. The concentrations in samples analyzed were found to be in the range of 0.88-1.88 mg/kg for Mn, 11.95-25.25 mg/kg for Fe, 0.35-1.22 mg/kg for Cu, 6.92-17.96 mg/kg for Zn, 0.03-0.07 mg/kg for Ni, 0.955-1.45 mg/kg for Cr and 0.564-0.85 mg/kg for Pb. However, Arsenic was not detected in all the samples analyzed. As for the anti-nutritional factors, the concentrations in samples analyzed were found to be in the range of 111.35-123.42 mg/kg for saponins, 69.5-509.4 mg/kg for oxalates, and 0.38-0.156 mg/kg for phytate and 316.95-325.27 mg/kg for cyanogenic glycosides. The values of all these elements were found significantly below the recommended maximum tolerable guidelines level proposed by WHO/FAO except for lead (Pb), Pb was found slightly higher than the recommended limit as described. Our findings of this study reveal that most of the trace elements found in M. oleifera are below the recommended maximum tolerable limits; therefore it is safe for both human and animal consumption as well.

Nutritional comparison of experimentally and commercially sun-dried lean fish and small prawns of Bangladesh

“…Besides, minerals such as iron, iodine, zinc, copper, calcium, phosphorus and magnesium are abundant in dry fish contributing significantly to our daily requirements for these nutrients [5][6][7][8][9][10]. Alongside providing ample amounts of such nutrients of public health importance, dry fish also contributes substantially to the export economy of Bangladesh; in 2019-20, Bangladesh earned around US$ 7 million (1 US$ = 80.59 Bangladeshi Taka) by exporting 4141.5 metric tons of dry fish of various types, which is the highest earnings from exporting dry fish in the last couple of decades [11].…”