Chemical composition of hydrodistillation and solvent-free microwave extraction of essential oils from Plectranthus amboinicus and Melaleuca cajupati leaves and their repellent activity

Abstract

Extraction of the native plants Plectranthus amboinicus and Melaleuca cajupati leaves have been carried out using traditional hydrodistillation (steam distillation) and solvent free microwave-assisted extraction methods at different temperatures and microwave irradiation powers. The chemical compositions of the essential oils extracted were identified using gas chromatography analysis. The ideal extraction time for Pletranthus amboinicus and Melaleuca cajupati were 120 min with microwave power 200 W and 400 W, respectively with the calculated extraction yield were 0.034 % and 0.276 %, respectively. In this paper, the results of the selected microwave powers, first oil drops, and extraction time are presented as well as the findings of the chemical compositions present in both plants are also discussed.