Chemical analysis of essential oils of Thymus Carmanicus Jalas by gas chromatography-mass spectrometry and toxicity activity agains t the major Iranian malaria vector, Anopheles Stephensi

In the last few years, using chemical insecticides to control the malaria vector has caused environmental pollution and resistance to chemical insecticides. This study aimed to investigate the chemical analysis of essential oils of Thymus carmanicus Jalas by gas chromatography and mass spectrometry (GC-MS) and toxicity activity against the major Iranian malaria vector, Anopheles stephensi. The essential oil of Thymus carmanicus Jalas was prepared from dried leaves using the hydro-distillation method. Gaschromatography-mass spectrometer (GC-MS) was used to analyze and identify thyme essential oil compounds. Bioassay was performed using World Health Organization (WHO) standard test. The T. Carmanicus Jalas essential oil consisted of ۱۵ compounds, with Carvacrol (۶۱%), Thymol (۶%), and β-caryophyllene (۵%) being the major components by volume. The LC۵۰ and LC۹۰ of thyme oil were ۲۰.۳۷ and ۴۱.۳۸ ppm at ۲۴h after application, respectively. At ۲۴h after application, significant differences were observed between the toxicity of ۵%, ۲۰%, ۲۵%, ۴۰%, ۵۰%, and ۸۰% concentrations of Thyme essential oil (P<۰.۰۵). The ۸۰% concentration of Thyme essential oil exhibited ۱۰۰% toxicity against A.stephensi larvae at ۲۴h after application. T. Carmanicus has a rich source of bioactive compounds for use as a mosquito larvicide.

کلیدواژه ها:

Chemical analysis ، Gas Chromatography-Mass Spectrometry ، Thymus Carmanicus Jalas ، Essential oil ، Malaria