Comparison of Microwave-Assisted Hydrodistillation and and Traditional Hydrodistillation Methods for the Rosmarinus eriocalyx essential oils from Eastern Morocco

Abstract

Volatile compounds of Rosmarinus eriocalyx samples were extracted by steam-hydrodistillation ( HD) and microwave-assisted hydrodistillation (MAH). GC-MS and GC-FID analysis of the oils revealed the presence of 22 and 26 compounds in the essential oi ls obtained through HD and MAH, respectively. The total yield of the volatile fractions obtained thro ugh HD and MAH was 1.21% and 1.47%, respectively. The two oils contained the same dominant components: camphor (35.92% HD; 35.33% MAH), camphene (19.74%; 17.07%), α-pinene (14.53%; 12.87%), and 1,8-cineol (6.52%; 6.73%). Higher amounts of oxygenated monoterpenes such as borneol, 1,8-cineol, isobornyl acetate, α-terpeneol, caryophyllene oxide (13.59%) were present in the oil of MAH in comparison with HD (12.36%). However, HD oil contained more monoterpene hydrocarbons such as tricyclene , α -pinene, camphene, o-cymene and limonene (39.04%) than MAH extracted oil (34.45%).