Bioassay-guided isolation of dehydrocostus lactone from Echinops kebericho as potential biopesticide against Aedes aegypti.

Abstract

Dengue fever is the most prevalent viral infection, which transmits by the vector mosquito Aedes aegypti and Aedes albopictus. The development of an effective dengue vaccine is still challenging. Thus, the prevention and control of dengue depend on controlling the transmitting vectors. Traditionally, Echinops kebericho roots are known to have mosquito-repellant properties. Dehydrocostus lactone, one of the major constituents of the roots extract, showed similar larvicidal activity as the standard pesticide permethrin (100% mortality) against the larvae of A. aegypti at 10 µg/mL concentration at 24 h exposure. The derivative compound (13-methoxy dehydrocostus lactone) was inactive against the larvae of A. aegypti. The structure-activity relationship (SAR) suggested that the presence of α- methylene and γ- lactone moieties are responsible for the larvicidal activity of dehydrocostus lactone against the larvae of A. aegypti. Overall, dehydrocostus lactone can be a potential biopesticide against the dengue vector mosquito, A. aegypti.