Determine optimum of harvest time on the quantity/quality of essential oil and thymol of thyme (Thymus vulgaris L.) in Isfahan

Background & Aim: Thyme is common named Thymus vulgaris L. belongs to Lamiaceae family. Thyme is a most important medicinal plant that was used in pharmaceutical, food, cosmetics hygienic industries in most of developed countries. Experimental: Determine optimum of harvest time this plant was done in a random block design with three replications was conducted in field Islamic Azad University of Khorasgan (Isfahan) 2009 and 2010. Treatment phonological stages such as: 1) before flowering stage; 2) at beginning of flowering stage; 3) 50% blooming stage; 4) at full flowering step and 5) at fruit set stage. The essential oil obtained by hydro-distillation using a Clevenger- type apparatus and, was analyzed by GC and GC/MS. Results & Discussion: Statistic analysis showed that the effects phonological stages had significant effect on essential oil yields & percent, thymol. The highest essential oil content (2.42%) was extracted at the beginning of flowering stage. Analysis and identification of components showed thymol main compounds in all samples. Industrial/Practical recommendation: According to the results of this project 50% blooming stage optimum of harvest time on the Quantity/Quality of Essence and thymol of Thyme.