Determination of levels of essential and non-essential metals and nutritional value in mung bean seed (Vigna radiate L.) cultivated in wolaita zone, southern Ethiopia

Mung bean (Vigna radiate L.) is an important legume crop grown worldwide from tropical to sub-tropical areas. The experiments were conducted on the mung bean to determine the level of essential and non-essential metals and proximate composition.

In this study, the levels of selected essential metals and non-essential metal were determined from mung bean (Vigna radiate L.) in Kindo Koysha District, Wolaita Zone, Ethiopia. Wet digestion method with a mixture of 6 ml of concentrated HNO₃: HClO₄ (5: 1 v/v) was used for digestion of the mung bean samples and a concentrated reagent mixture of 6 mL aqua-regia (3: 1 ratio of HCl to HNO₃) and 1.5 mL H₂O₂ was used for digestion of the soil samples.

The results obtained revealed that the concentrations of metals in the mung bean samples in mg/kg dry weight were in the range of Ca (1418.02–1698), Mg (2422–2492.4), Na (88.9–106.7), K (3670–3716.8), Fe (196.2–235.5), Zn (72–103), Mn (51–97.6), Cu (7.8–27.4). The non-essential metal Cr was not detected in mung beans. The proximate composition of mung bean in the range of crude protein (17.86–28.29%), crude fat (1.05–1.49%), ash content (2.9–3.35%) and moisture (5.76–7.57%). Mung bean was found to be an excellent source of essential minerals and protein content and low in fat content.