Determination of Some Essential Metals in Selected Medicinal Plants

Abstract

Medicinal plants are sources of different essential metals that have different biological activities including those useful in the treatment of human diseases. Among the indigenous medicinal plants used as phytomedicines for the treatment of many diseases in Kano State are Annona squamosa, Psidium guajava, Anacardium occidentale, Ficussycomorus and Pomegranate. The aim of this study was to determine the levels of essential metals present in the herb tissues (leaf and stem) samples obtained from Kwarin Gogau garden, airport road, Kano State. The plant samples were collected, pretreated and digested by wet digestion method and analyzed using Micro Plasma Atomic Emission Spectrophotometer (MPAES). The results obtained in this study showed that extracts of the medicinal herbs investigated contained essential metals. The mean concentrations range for essential metals were: Zn (0.109-0.658mg/kg), Cu (0.026-0.079 mg/kg), K (1.846 -11.669 mg/kg), Mn (0.039-1.269 mg/kg), Fe (0.019-0.107mg/kg), Ni (0.054-0.144 mg/kg). Comparing the results obtained with the permissible limits set by WHO for consumed medicinal herbs, it was concluded that the essential metals present in the herbs were below permissible limits. Also, there was no statistically significant difference between the plant tissues samples analyzed for Zn, Cu, K, Mn, Fe, and Ni (P>0.05).