The diverse field of chemistry like structural and Analytical chemistry has offered the tools that are essential for purifying the plethora of phytochemical constituents. Such an untapped pool of phytochemicals from the plant world can be used as an alternative to synthetic insecticides in mosquito vector control programme. This investigation has used the Bioassay-guided Chromatography, Fourier-transform infrared spectroscopy (FTIR), Nuclear magnetic resonance (NMR) and GC-MS (Gas chromatography–mass spectrometry) to isolate and identify the most prominent toxic phytocompounds from the medicinal plants Xanthium strumarium and Acmella calva. The Map of the study site has been prepared using the Q-GIS. SPSS was used to perform the probit regression analysis and plot preparation. The isolated compounds such as Undecane (CH3(CH2)9CH3; 156.31 g/mol) (LC50: 2.599 mg/L (2.251 - 2.867); LC90 : 4.563 mg/L (3.960 - 6.006) and Phthalic acid, butyl undecyl ester (C23H36O4; 376.5 g/mol) (LC50: 4.072 mg/L (3.680 - 4.462); LC90: 6.894 mg/L (5.821-10.303) those are isolated from the Xanthium strumarium, and Acmella calva could be recognized as an innovative direction for the conception of natural insecticide against the Culex quinquefasciatus mosquito vectors since they produced a maximum range of toxicity. Moreover, the production of excessive free radicals in the phytocompounds exposed mosquito strain illustrated the probable role of oxidative stress in larval death. This investigation recommends that the isolated compounds can be used as an eco-friendly approach for mosquito control in the future.

Introduction: Plant-based knowledge has been used for generations for personal protection from various mosquito species. The notion of applying such traditional perspectives in vector control research has received extensive attention in recent years. Unlike other common patterns, the present investigation has tried to explore the augmented production of reactive oxygen species (ROS) in response to Stachytarpheta jamaicensis exposure with special inference on larvicidal potential, mode of action of phytochemical compounds, and oxidative stress. Methods: The larvicidal potential was determined as per the WHO protocol. Ultraviolet-visible spectroscopy was used to determine the excessive production of ROS. GC-MS was employed to characterise the phytochemical constituents. The statistical analysis was done by using SPSS version 24.0.0. Result: The acetone extract has been found to exhibit a maximum range of toxicity in terms of larvicidal potential and reactive oxygen species formation. Among the 40 phytochemical elements characterised, Cyclopropane, 1,1,2,2-Tetramethyl; Phenyl-Acetonitrile; Pyranone; Tetradecene; Neophytadiene; Mome Inositol; Monocrotaline; and Squalene may be responsible for the augmented production of ROS in the Culex quinquefasciatus. Conclusion: The phytochemical elements in Stachytarpheta jamaicensis displayed extensive toxicity and inhibited the normal development of Culex quinquefasciatus mosquitoes by augmented production of reactive oxygen species, indicating its prominent role in oxidative stress.