Insects. 2020 Mar 22 ;11(3). Epub 2020 Mar 22. PMID: 32235733
Larvicidal and Repellent Activity ofL. Essential Oil against.
Dengue is one of the most dangerous vector-borne diseases transmitted bymosquitoes. The use of mosquito repellents to protect human hosts and insecticides to reduce the mosquito population is a crucial strategy to prevent the disease. Here, we reported larvicidal and repellent activities ofL. essential oil against, the main vector of the disease. The essential oil was extracted by hydro-distillation from the aromatic plant grown in Vietnam. The yield was 0.67% based on the weight of fresh leaves. The essential oil was analyzed by gas chromatography-mass spectrometry (GC-MS). The main components were menthol (66.04%), menthyl acetate (22.19%), menthone (2.51%), and limonene (2.04%). Toxicity test onlarvae showed that the median lethal concentrations, LCand LCwere 78.1 ppm (part per million) and 125.7 ppm, respectively. Besides, the essential oil showed excellent repellency onmosquitoes. At 25%, 50%, and 100% concentration, the respective complete protection times (CPTs) were 45 min, 90 min, and 165 min. When adding 5% vanillin to the essential oil (25%), the complete protection time of the essential oil increased up to 120 min. In conclusion, the EO fromL. has been shown to be a promising natural larvicide and repellent againstmosquitoes.