Use of Multivariate Analysis for Clustering Between and Within Iranian Thyme Species for Essential Oil Components

Abstract

In this study essential oil components of sixteen thyme genotypes from 4 species (T. daenensis, T. kotschyanus, T. lancifolius, T. fedchenkoi T. pubescens) were assayed by GC and GC-MS. Total of 10 chemical compounds could be identified among these species. Thymol, carvacrol, geraniol and α-terpineol were reported more than 24 percentages (24.75 to 83.34%). It is evident that the highest levels of volume percentage of essential oils and thymol in first group of claster analysis, linalool, geraniol and geranyl acetate in second group and borneol and carvacrol in last group were observed. Factor analysis showed that three factors explain 70 percentage of variation between genotypes. These factors classified different chemical components to 3 chemical types (ether, alcohol and total essential oil, phenol). Regarding the PCA analysis, T. kotschyanusi (Azerbayjan) and T. pubescens (Zanjan) were highly correlated with borneol, p-cymene and cineole. Also T. daenesis (Markazi), T. lacifolius (Markazi) and T. daenesis (Isfahan/Ferydan) were highly correlated with total essential oil.