Larvicidal properties of essential oils of three Artemisia species against the chemically insecticide-resistant Nile fever vector Culex pipiens (L.) (Diptera: Culicidae): In vitro and in silico studies

Abstract

The objective of this study is to determine the larvicidal activity of essential oils (EOs) extracted from three plants of the genus Artemisia against the mosquito Culex pipiens (C. pipiens) using in vitro and in silico studies. A total number of 20 third- and fourth-instar larvae were exposed to various concentrations of the three plants. The LC50 and LC90 values of the tested Artemisia EOs were determined using Probit analysis. In addition, the sensitivity of C. pipiens to these EOs was determined and compared against a standard insecticide, temephos, under laboratory conditions. Furthermore, in silico assessments were carried out on the major constituents to help understand and explain the acquired in vivo results. Gas chromatography analysis identified the major compounds as d-limonene and β-pinene for Artemisia flahaultii, camphor and borneol for Artemisia. aragonensis, and artemisia ketone and caryophyllene for Artemisia annua. A. flahaultii oil showed the highest efficacy against C. pipiens larvae, followed by A. annua oil with average larvicidal activity. In contrast, A. aragonensis EO, composed of a high percentage of monoterpenes, was the least active. Docking simulation indicated that several studied ligands had promising binding scores within the receptor’s binding site compared to the reference insecticide temephos. The obtained results allow us to conclude that A. flahaultii, a species endemic to Morocco, is an excellent means of controlling C. pipiens.

Keywords

• artemisia species
• essential oil
• culex pipiens
• vector
• bioassay larvicide
• lethal concentration
• endemic
• in silico