Determination Of Selected Essential Elements In Traditional Vegetables, Medicinal Plants, Fruits And Conventionally Grown Vegetables In Koibatek, Kenya

ABSTRACT

There is growing awareness about the efficacy of essential elements in the maintenance of good health and prevention of diseases. Zinc plays a vital role in wound healing, immune system, reproductive system and nervous system. Zinc wades off oxygen free radicals and also aid in metabolism of carbohydrates by assisting insulin to function. Chromium lowers blood sugar and also works with insulin in metabolization of sugar, while copper is required for conversion of body’s Fe into haemoglobin. Copper lowers low density lipoprotein (LDL) cholesterol, raises high density lipoprotein (HDL) cholesterol and prevent oxidation of low density lipoprotein (LDL) cholesterol. Iron is necessary for production of haemoglobin, immune functioning and drug detoxification. Manganese aids in maintenance of blood glucose level, synthesis of interferon, energy production and bone growth. In this study Zn, Cu, Mn, Fe and Cr in selected traditional vegetables, fruits, medicinal plants and conventionally grown vegetables growing/found in Koibatek district (Kenya) were determined using atomic absorption spectroscopy (AAS) and energy dispersive X- ray fluorescence (EDXRF). This study analysed the elemental contents of a total 312 randomly collected plant samples. In this study Zn, Fe, Cu, Mn and Cr were detected in all the samples, and the results indicated that traditional vegetables and medicinal plants had high levels of these elements compared to conventionally grown vegetables. However, traditional vegetables had the highest levels of the specified essential elements of all the plant samples analysed. Amaranthus hybridicus had the highest levels of Zn (77.62 ± 33.09 mg/kg), while Gynandropsis gynandra was the best source of Fe (1108.00 ± 410.28 mg/kg). Utica massaica had highest levels of Cr (28.28 ± 18.08 mg/kg) while Gallinsoga paruiflora was the best source of Cu (14.47 ± 6.97 mg/kg). Essential elements leached into the surrounding cooking water when traditional vegetables were boiled and the loss was significant in some samples. There were positive and negative correlations between certain metal pair interactions for instance in vegetables there was a high degree of positive correlation in Mn-Cr interaction (r = 0.87). The research findings will help the people of Koibatek district to achieve food security, manage micronutrient deficiencies and to generate income through utilization or sale of traditional vegetables, fruits and medicinal plants from wider sources.