Location: Mosquito and Fly ResearchTitle: Toxicity of compounds isolated from white snakeroot (Ageratina altissima) to adult and larval yellow fever mosquitoes (Aedes aegypti)
Submitted to: Natural Product Communications
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/18/2016
Publication Date: 11/15/2016
Citation: Estep, A.S., Becnel, J.J., Lee, S.T. 2016. Toxicity of compounds isolated from white snakeroot (Ageratina altissima) to adult and larval yellow fever mosquitoes (Aedes aegypti). Natural Product Communications. 11(11):1675-1677.
Interpretive Summary: Botanical extracts have been the source for several classes of pesticides for mosquitoes. However, increasing resistance to these products and reduced numbers of choices necessitate the search for new active ingredients. Ageratina altissima, or white snakeroot, is found throughout the eastern United States and econtains known toxic compounds. We examine chromenes (benzopyrans) and benzofurans isolated from this plant for larvicidal and adulticidal activity against the dengue vector Aedes aegypti. Initial activity identified several compounds that were effective against either larvae or adults. Interestingly, only two compounds were effective against both larva and adults. Dose curves were constructed from further testing of these active compounds to allow comparative ranking of efficacy. We identified dehydrotremetone as the most effective larvicide and 6-acetyl-7-methoxy-2,2-dimethylchromene as the most effective adulticide although other compounds were also active. This study provides additional useful data for evaluation of chromenes and benzofurans as possible mosquiticidal agents.
Technical Abstract: Because of increasing insecticide resistance, new pesticides are needed. Flowering plants have been the source of useful pesticides in the past. We studied 15 chemicals isolated from a poisonous pasture plant for activity against the yellow fever mosquito. We found that dehydrotremetone was effective against larval mosquitoes while 6-acetyl-7-methoxy-2,2-dimethylchromene was the most effective against adult mosquitoes. The structure of these chemicals is similar to others that have shown insecticidal activity. This information may be useful to guide further designs.