Larvicidal potential, phytochemical composition, and molecular docking analysis of Panicum repens as a natural insecticide

ABSTRACT Mosquito-borne diseases, including malaria and dengue fever, remain a significant public health concern, especially in developing regions. The limitations of synthetic insecticides, such as resistance and environmental impact, have driven the search for sustainable alternatives. This study evaluated the larvicidal potential of Panicum repens extracts against three mosquito species namely Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus. Sequential Soxhlet extractions using methanol, ethanol, chloroform, n-hexane, and water revealed that the methanol extract exhibited the highest efficacy, achieving LC50 and LC95 values of 87.04 ppm and 215.68 ppm, respectively, for Cx. quinquefasciatus. Mortality rates increased dose-dependently, with Cx. quinquefasciatus being the most susceptible species. Gas Chromatography-Mass Spectrometry (GC-MS) analysis identified key bioactive compounds, including stigmasterol, gamma-sitosterol, and campesterol, with sterols representing a significant proportion of the methanol extract. The docking analysis of 4,4,6a,6b,8a,11,11,14b-Octamethyl-docosahydropicen-3-ol with the target protein 5X61 demonstrated the highest binding affinity, with a docking score of −10.5 kcal/mol. The binding interaction involved both hydrogen bonding and hydrophobic interactions. The molecular docking results provide insights into the potential mechanisms of action of these bioactive compounds, supporting their application in the development of targeted, eco-friendly mosquito control strategies. P. repens methanol extract shows promise as a natural, eco-friendly larvicide for mosquito control.