COMPONENTS AND TOXICOLOGICAL EFFECTS OF MYRTUS COMMUNIS L. (MYRTALES: MYRTACEAE) ESSENTIAL OIL AGAINST MOSQUITO CULEX PIPIENS L. (DIPTERA: CULICIDAE)

The purpose of the present study was to determine the chemical composition of Myrtus communis L. essential oil (EO) and to assess its effectiveness against newly exuviated fourth instar larvae and adults of Culex pipiens . The EO of the plant was extracted by hydrodistillation and its chemical profile has been analyzed by gas chromatography coupled with mass spectrometry (GC-MS) method. During this analysis, 36 Compounds were identified and the main components were alpha-Pinene (50.81%) and 1.8-Cineole (18.98%). The EO toxicity was tested using several concentrations (100, 200, 400, 600, 700 mu l/ml) and lethal concentrations (LC50 and LC90) were estimated at 329.5 mu l/ml and 737.6 mu l/ml against fourth-instar larvae. The adulticidal effect of this EO was tested using different concentrations ranging between 0.15 and 1.25 mu l/ml air and their lethal concentration values were estimated. The EO of M. communis L. applied at its LC50 and LC90 against fourth-instar larvae and the effect action pathway was studied using the acetylcholinesterase (AChE) and glutathione S -transferase (GSTs) biomarkers analyzes. These Biomarkers analyzes have confirmed the neurotoxic activity and activation of the detoxification system. It was concluded that M. communis EO exhibits insecticidal effects against Cx. pipiens and could be considered as a potential alternative to conventional insecticides.