Mosquito larvicidal potential of hydroxy-2-methyl-4H-pyran-4-one (MALTOL) isolated from the methanol root extract of Senecio laetus Edgew. and its in-silico study

In the present study, hydroxy-2-methyl-4H-pyran-4-one was isolated from the methanol root extract of Senecio laetus and was identified by FT-IR, H-1, C-13 NMR and GC-MS. The larvicidal potential of the compound 3-hydroxy-2-methyl-4H-pyran-4-one was evaluated against the 4(th) instar larvae of Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus at concentrations ranging from 20 to 1.25 ppm under laboratory conditions. The compound showed 100% mortality at 20 ppm against all the tested mosquitoe species and the LC50 and LC90 values were 1.22 and 7.25 ppm (An. stephensi), 2.10 and 99.84 ppm (Ae. aegypti) and 3.88 and 12.47 ppm (Cx. quinquefasciatus), respectively after 24 h of exposure period. In silico molecular docking study results reflects that hydroxy-2-methyl-4H-pyran-4-one compound showed highest binding affinity with OBP of Cx. quinquefasciatus (Glide energy score - 7.3 kcal/mol(-1)). The larvicidal activity of hydroxy-2-methyl-4H-pyran-4-one against tested mosquito species appears interesting and may be developed after toxicological and field evaluation.

Automated summary

In this study, hydroxy-2-methyl-4H-pyran-4-one was isolated from the methanol root extract of Senecio laetus and evaluated for its larvicidal potential against three mosquito species. The compound showed promising results with high mortality rates, especially against Cx. quinquefasciatus. Further toxicological and field evaluations may lead to the development of this compound as a potential insecticide.