Comparison of the composition and cost estimation of steam distillation and supercritical fluid extraction from leaves of Lippia graveolens

Abstract

Lippia graveolens, mostly known as Mexican oregano, is an aromatic plant with great economic importance. However, very little is known about the reasons that could explain the variation observed in the yield and composition of the essential oil and extract obtained. The effect of steam distillation and supercritical fluid extraction processes on composition, yield, and economic, viability were evaluated. The essential oil and extract were obtained through steam distillation using analytical scale equipment and supercritical extraction equipment, respectively. The extracts were analyzed by GC-MS. Carvacrol was the majority compound in both processes. In the case of steam distillation, a maximum yield of 4.1 % on a dry weight basis was obtained, while the supercritical fluid extraction obtained provided a maximum yield of 2.8 % on a dry weight basis at the same bed porosity (0.91). The cost was obtained over a period of one year. The process of extraction by steam distillation showed good results to obtain essential oil from L. graveolens. It is observed that steam distillation remains the optimal choice.