Abstract This research investigates the extraction and characterization of essential oils from lemongrass (Cymbopogon citratus) and scent leaf (Ocimum gratissium), two plants known for their mosquito repellent properties. The essential oils were obtained using hydro-distillation and analyzed for their physico-chemical properties and chemical composition using ASTM standard methods and Gas Chromatography-Mass Spectrometry (GC-MS). Results showed that lemongrass oil had a higher specific gravity (1.027) and was dominated by fatty acid esters (64%) and diterpenes (21%), suggesting a slow-release profile suitable for long lasting repellency. In contrast, scent leaf oil exhibited higher volatile content (9.55%) and a chemically diverse profile, including monoterpenes (19.13%), sesquiterpenes (15.17%), and various fatty acids (33.57%), indicating strong immediate repellency. The chemical difference between both oils is linked to plant type, environment, and extraction conditions. Their combined use offers a synergistic solution for developing effective, natural mosquito repellents that provide both rapid and sustained action. This study highlights the relevance of essential oil profiling in formulating plant-based alternatives to synthetic repellents and calls for further toxicological and field efficacy studies to support commercial application.
Ataire et al. (Fri,) studied this question.