Growth Stage and Drying Methods Affect Essential Oil Content and Composition of Pickling Herb (Echinophora tenuifolia subsp. sibthorpiana Tutin)

The present research was conducted during 2012 in order to determine the essential oil content and composition of Echinophora tenuifolia subsp. sibthorpiana Tutin. Plants were collected during rosette, vegetative growth, full flowering and fruit-ripening stages. Oil was extracted using Clavenger hydro-distillation apparatus from either fresh, shade dried or sun dried samples. Oil composition was determined with a GC/MS. Oil content of samples showed significant variation during the vegetative stages of development. Oil contents of fresh samples were found to be 0.76% at seedling stage whereas oil content has risen to 1.06% at seed set. The shade-dried samples had higher oil contents than the fresh and sun dried samples. The oil composition of pickling herb changed with drying method and growth stage. Throughout the growth stage of the plant, the oil was composed of 21 components and the main components were found to be α- phellandrene (47.43 - 66.39%) and methyl eugenol (21.29 ? 38.72%). While methyl eugenol content decreased during vegetation period for both fresh and dried samples, α-phellandrene level increased. Attention should be given to the collection time and drying method of pickling herb for different uses since vegetative stage and drying method influence oil content and composition.