Comparison of microwave-assisted hydrodistillation with the conventional hydrodistillation method in the extraction of essential oil (lemongrass and star anise)

Microwave-assisted hydrodistillation(MAHD)has recently been developed for the extraction of essential oils from plant materials.In this study,microwaveassisted hydrodistillation was investigated for the extraction of essential oils from lemongrass and start anise and the results were compared with those of the conventional hydrodistillation in terms of extraction time,extraction yield/efficiency and chemical composition.Microwave-assisted hydrodistillation was efficient in extraction in terms of extraction time and energy saving.Lemongrass and star anise was in the ratio of 1:10 with water and the essential oils components were identified using GCMS.There were significant different in the extraction yield of essential oils from both of the method and higher yield were obtained from MAHD method. Results of analysis from gas chromatography-mass spectrometry indicated that the use of microwave in hydrodistillation did not adversely influence the composition of essential oils.Microwave-assisted hydrodistillation was found to be environmentally friendly due to its shorter extraction time and therefore lower energy consumption