Larvicidal activity and phytochemical composition of Kyllinga brevifolia (Poales: Cyperaceae) against mosquito vectors

Vector-borne diseases, primarily transmitted by mosquitoes, contribute significantly to global mortality and morbidity, particularly in tropical regions. The increasing resistance of mosquito species to synthetic insecticides, alongside the environmental and health concerns associated with chemical control methods, has led to the exploration of plant-based alternatives. In this study, the larvicidal potential of Kyllinga brevifolia extracts, obtained using solvents of varying polarity (n-hexane, chloroform, ethanol, methanol, and aqueous) was evaluated against early 4th instar larvae of Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus. Ethanol also had the lowest LC50 and LC90 values among all extracts for the three species, indicating its superior larvicidal activity. For instance, the LC50 in Ae. aegypti was 105.84 ppm and the LC90 was 182.48 ppm, while in An. stephensi, the LC50 and LC90 were 75.55 ppm and 152.18 ppm, respectively, and in Cx. quinquefasciatus, these values were 87.67 ppm and 164.30 ppm. Phytochemical analysis revealed the presence of key bioactive compounds such as alkaloids, phenols, saponins, and terpenoids, while gas chromatography-mass spectrometry (GC-MS) identified campesterol (19.90%) and stigmasterol (19.86%) as the most abundant components. This research marks the first reported larvicidal activity of K. brevifolia and highlights its potential as a novel biopesticide for vector control. Statistical analyses confirmed the significant influence of extract type, concentration, and species interactions on mortality rates, supporting the use of K. brevifolia in eco-friendly mosquito management strategies.