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