LARVICIDAL ACTIVITY OF THE METHANOLIC EXTRACT OF Warbugia ugadensis SEED OIL ON Aedes aegypti

Abstract

Mosquito is a vector implicated with Vector-borne diseases such as malaria (Anopheles’ species) dengue (Aedes species) and west Nile fever (Culex species). Kenya experiences mosquito-borne disease outbreaks with the recent ones being the dengue virus and chikungunya disease outbreak that occurred along the coast of Kenya. Medicinal plants such as Warburgia ugandensis that possess larvicidal activity, have major importance in the control of mosquitoes. This study investigated the larvicidal activity and phytochemical screening of the methanolic extract from the seed’s oil of Warburgia ugandensis. Quasi-experimental research design was used as the study design. The plant was identified and authenticated by a taxonomist. Mature fruits of Warburgia ugandensis were obtained from the school of pharmacy’s botanical garden and seeds were separated and washed. Seeds were air-dried, and crushed. Half of the GSP was used to extract seed oil while the other half was subjected to various phytochemical screening. The larvicidal activity of the plant extracts was evaluated according to the World Health Organization guidelines for laboratory and field testing of mosquito larvicides. The activity of the methanol plant extract was evaluated at 25, 50, 100, and 125 ppm to determine the LC50 value. Permethrin was used as a positive control. About 8.06% of the seed oil was extracted. The seed oil and the leaves had a characteristic odour, a bitter taste, and pale yellow in color. Alkaloids, fixed oils, tannins, and phytosterols were abundantly present in the seed. Proteins and carbohydrates were moderately present while saponins were slightly present. Bioassays on mosquito larvae indicated larvicidal activity of methanolic seed oil extract of Warburgia ugandensis against Aedes aegypti at concentrations of 25, 50, 100, and 200 ppm. Seed oil of Warbugia ugandensis contains phytochemicals that possess larvicidal activity against Aedes aegypti mosquito species.

Keywords: Larvicidal Activity, Lethal Concentration, Lethal Dose, Warburgia Ugandensis