Analysis of mineral and heavy metals in Eugenia polyantha, anacardium occidentale, and Oroyxylum Indicum Plants

Plants and their extracts deserve special attention because of the important influence they have on human health. For the majority of the world population,plants represent the primary source of the health care. According to the World Health Organization (WHO) report, almost 80% of people in marginal communities use plants for consumption or for the treatment of various diseases. Although, the effectiveness of the plants is mainly associated with their constituents such as essential oils, vitamins, glycosides and many other products but prolonged intake can cause health problems due to the presence of heavy metals. The human body requires both the metallic and the non-metallic elements within certain permissible limits for growth and good health. Therefore, the aim of this study was to identify the mineral (Na, Mg, Ca, Al and K) content and heavy metals (Pb, Cd, Cu, Zn and Fe) content in Eugenia polyantha, Anacardium occidentale and Oroxylum indicum, and also to compare the efficacy of different methods for heavy metal and mineral plant analysis. Such information could be helpful for the local communities as they are consuming this plant in a vast amount. The two different extractions viz., dry ashing and wet digestion method was used in order to distinguish the effectiveness of both methods in retaining the elements in the plants during the extraction process. The concentration levels (mg/L) of selected heavy metals and mineral in the plants were determined by using atomic absorption spectrophotometer (AAS). Eugenia polyantha, Anacardium occidentale and oroxylum indicum contains all the minerals listed and heavy metals except for Cd at different levels of concentration. These plants are found to be rich in Ca, Mg and K with a very high concentration ranging from 20 — 400 mg/L and have a very low heavy metal accumulation. The mean concentration of the 5 different heavy metals did not exceed 1 mg/L. Moreover the results indicate that dry ashing method was more efficient in , determining Na, Mg, Ca, Al, Pb, Cu, Fe, and Zn elements and wet digestion method for K.