Evaluation of Larvacidal Activity of Olea europaea Extract against Anopheles Mosquito in In vitro, Fogera Woreda, North Western Ethiopia

Abstract

Mosquitoes are the major public health threat as they are the vectors of malaria. Since mosquitoes developed resistances towards chemical insecticides, researchers are searching for alternative control measures. Secondary metabolites and bioactive chemicals present in plants serve as a defense mechanism against insects’ larvae. Therefore, the aim of this study was to evaluate larvacidal activities of Olea europaea (O. europaea) extracts In vitro against 3rd-4th instars larvae of Anopheles arabiensis. The fresh leaves of the plant were collected from Fogera Woreda and brought to Bahir Dar University to be extracted by petroleum ether, chloroform, acetone and ethanol. The extract was filtrated using Buchner funnel with Whatman filter paper; undergone rotary evaporator and stored at -4 C until larvicidal bioassay test. Furthermore, the phytochemical screening was carried out and appropriate solution was prepared. Larvae of A. arabiensis were collected from Woreta town and bioassay was performed on 20 larvae at room temperature. The percentage mortality at 24, 48 and 72 hours was computed. The result showed that petroleum ether, chloroform, acetone and ethanol extracts of O. europaea has resulted in significant mortality of larvae (P=0.00). All solvent extracts showed increased mortality rate with time and concentrations. Based on the current result, we recommend that further studies are needed to characterize active ingredients of screened phytochemicals and evaluate their toxicity, and to study their impacts on human health and non-target organisms in mosquito habitats.