HO-01: Effect of Juniperus phoenicea essential oil on toxicity and energy reserves of Culiseta longiareolata (Diptera: Culicidae) from Tebessa (Algeria)

Abstract

Diptera insects are considered dangerous medicinal and veterinary insects worldwide, especially mosquitoes (Culicidae). These insects negatively affect human and animal health. Culiseta longiareolata is one of mosquito species responsible for the transmission of avian Plasmodium and West Nile virus. Worldwide, several synthetic insecticides have been used to eradicate this population. Unfortunately, insecticide resistance among mosquito populations has been reported. In this context, it is necessary to propose new specific alternatives. Among the alternatives, natural products derived from plants. Objectives: In this context, the essential oil of the plant juniperus phoenicea was tested in the laboratory on fourth instar larvae of the species Culiseta longiareolata. Their action has been evaluated on several aspects: Toxicological and biochemical. Methods: The essential oil was isolated by hydrodistillation using a Clevenger-type hydrodistillator for 3 h for extraction. The principle of the toxicity test is to treat fourth stage Culiseta longiareolata larvae with Juniperus phoenicea essential oil preparations. These preparations have increasing concentrations (5- 15 ul), dissolved in 1 ml of ethanol. For each concentration did made three repetitions each comprise 20 larvae. The treatment was applied for 24 h. The quantification of proteins was carried following the Bradford (1976) method, Carbohydrates were determined following the Duchateau and Florkin (1959) method and Lipids were measured by the Goldsworthy et al. (1972) method. Results and discussion: The toxicological tests made it possible to determine the lethal concentrations (LC25, LC50 and LC90) of oil extracted from juniperus phoenicea on the newly exuviated larvae. In a second series of experiments the essential oil significantly reduces the energy reserves (protein, lipid and carbohydrate) of the larvae