Chemical composition and bioactivities of Rosmarinus officinalis and Jasminum officinale essential oils against Culex pipiens and Aedes aegypti: Larvicidal, antibacterial, and antioxidant assessment

Plants are a sustainable source of bioactive components for medical and agricultural fields. This study evaluated the chemical composition, antioxidant capacity, antibacterial activity, and larvicidal potential of Rosmarinus officinalis (rosemary) and Jasminum officinale (jasmine) essential oils against Culex pipiens and Aedes aegypti larvae. GC/MS analysis revealed that rosemary oil was dominated by oxygenated monoterpenes (eucalyptol 29.51% and camphor 21.44%), while jasmine oil primarily contained aromatic esters (benzyl acetate 41.0%) and monoterpene alcohols (β-linalool 8.38%). Rosemary oil exhibited higher total phenolic and flavonoid contents, correlating with superior antioxidant (DPPH, FRAP, ABTS) and antibacterial activities against Escherichia coli, Staphylococcus aureus, Klebsiella spp., and Proteus spp. Larvicidal bioassays demonstrated that rosemary oil was more potent, with lower LC50 and LC90 values against both mosquito species. Biochemical analyses of treated larvae revealed significant inhibition of acetylcholinesterase, esterases, and metabolic enzymes (GABA-T, amylase, lipase), alongside elevated oxidative stress markers (LPO, TPC) and reduced antioxidant defenses (SOD, CAT, GST). These findings highlight the potential of rosemary and jasmine essential oils, particularly rosemary, as natural, eco-friendly agents with antioxidant, antibacterial, and insecticidal properties, supporting their application in vector control and as functional bioactive agents in food and health sectors.