Diversity and seasonal variation of essential oils for wild Coridothymus capitatus (L.) using GC-MS technique

Abstract

Essential oils of C. capitatus wild populations were quantitatively analyzed using gas chromatography and gas chromatography-mass spectrometry techniques. Significant diversity was obtained among wild C. capitatus populations. Thymol percentage ranged from 0.03 to 0.57%, and carvacrol percentage ranged from 0.10 to 0.90%. Populations showed average dissimilarity of 10.68. The unweighted pair group method with arithmatic mean (UPGMA) cluster analysis revealed thymol and carvacrol chemotypes. Monthly quantitative changes in thymol and carvacrol were obtained, the highest percentages of oil yields, thymol, carvacrol, and thymol plus carvacrol phenolic ingredients were recorded in July (2.45, 0.31, 0.87, and 1.19, respectively). The results of this study indicated that a broad range of genetic diversity exists among populations of C. capitatus collected from wild habitats in Jordan. The results obtained pave the road for a potential essential oil production from C. capitatus species.