Medicinal Plants Of Chuka Community In Tharaka Nithi County, Kenya And Some Of Their Selected Essential Elements

ABSTRACT

Medicinal plants are essential components of primary health care, especially for rural communities indeveloping countries. The medicinal plants contain essentialelements that are beneficial therapeutically. For example zinc plays a vital role in wound healing, nervous system, reproductive system and immune system. Chromium helps in metabolism and management of type-2 diabetes. Sodium is the chief extracellular ion and helps to maintain the body’s fluid balance while potassium is the body’s principal intracellular electrolyte, important in maintaining the fluid volume inside cells. Magnesium assists in the operation of more than 300 enzymes. It is also needed for the release and use of energy from energy-yielding nutrients. Iron is required for the making of new cells of amino acids, hormones and neurotransmitter. Calcium is an integral part of bone structure and the bone calcium. Medicinal plants are also known to contain secondary metabolites such as alkaloids, saponins, tannins, flavanoids and steroids among others. However, reports about levels of essential elements in medicinal plants and specifically on the medicinal plants used by the Chuka community are scarce. This study therefore undertook togather information on the knowledge and use of medicinal plants for treating various ailments as well as essential elements in the medicinal plant.The information obtained was used to collect and identify the common medicinal plants with the help of a Plant Taxonomist. Specimens of the same were deposited at East African Herbarium at the National Museums of Kenya. The levels of Zn, Fe, Cr, Mg, Ca, Na, Cu and K in 19 common medicinal plants used by Chuka community were determined using flame atomic absorption spectroscopy (FAAS) and flame atomic emission spectroscopy (FAES). The results obtained were analyzed using statistical package for the social sciences (SPSS). The study showed that 146 medicinal plants are used in the treatment of human beings and animals, with majority (97.9%) being used on the former. Analysis of variance (ANOVA) showed that levels of selected essential elements were significantly different from one plant to plant (p≤0.05 at 95% confidence level). The levels of K ranged from 1.50mg/Kg in stem bark of Mangifera indica to 455.00mg/Kg in leaves of Aloe secundiflora. The levels of Cu were 0.38 mg/Kg in Iboza ripariawhileEuclea divinorum registered levels below detection limit. The levels of Mgranged from 6.12 mg/Kg in Dovyalis abyssinicato 164.00 mg/Kg in Aloe secundiflora. Levels of Zn ranged from 0.35 mg/Kg in Eucalyptus saligna to 4.29 mg/Kg inAloe secundiflora, while levels of Crranged from 0.47 mg/Kg in leaves of Senna didymobotrya to 1.61 mg/Kg in stem bark of the same plant. Iron levels ranged from 0.74 mg/Kg in Bauhiniatomentosa to 20.40 mg/Kg in Eucleadivinorum. Levels of Na ranged between 2.69 mg/Kg in Bauhinia tomentosa and 8.45 mg/Kg in Aloe secundiflora. The leaves of Aloesecundiflora had the highest levels of essential elements studied while the stem barkofDovyalis abyssinica had the lowest levels. There was a negative correlation and positive correlations between certain metal pair interactions with high positive correlations between Mg-Na and Mg-Ca interactions (r = 0.823 and 0.887 respectively). The findings of this study will be used in developing sustainable use of medicinal plants. The information will be used to sensitize the community on use of medicinal plants.