GC–MS Profiling of Secondary Metabolites from Catharanthus roseus and Annona muricata Leaves and Their Larvicidal Potential Against Aedes aegypti

Abstract

Mosquito-borne diseases remain a major public health challenge in tropical regions, while increasing resistance to synthetic insecticides has intensified the search for environmentally friendly alternatives. This study aimed to identify the secondary metabolites present in ethanol leaf extracts of Catharanthus roseus and Annona muricata using gas chromatography–mass spectrometry (GC–MS) and to evaluate their larvicidal activity against Aedes aegypti larvae. Mature leaves were shade-dried, powdered, and extracted with ethanol. The concentrated extracts were analyzed by GC–MS, and compounds were identified by comparison with the NIST mass spectral database. Larvicidal bioassays were conducted using extract concentrations ranging from 0.5% to 2.5%, with larval mortality observed for 48 hours. Median lethal concentration (LC₅₀) values were determined using probit analysis. GC–MS analysis of C. roseus revealed several bioactive compounds, including phenol, 4-ethenyl-2-methoxy; tristrimethylsilyl-P-glycolate; and 3′,4′,5,6,7,8-hexamethoxyflavone, the latter being the dominant constituent. In A. muricata, 1,1,3,3-tetramethyl-1,3-diethoxydisiloxane was detected as the major compound, although its presence may be associated with analytical artifacts. Both extracts exhibited concentration-dependent larvicidal activity. The LC₅₀ values were 3.259% for C. roseus and 2.842% for A. muricata, indicating greater potency of the latter. These findings suggest that both plant extracts have potential as botanical larvicides against Aedes aegypti. Further studies are needed to confirm active compounds, optimize formulations, and evaluate environmental safety.