Evaluation of essential oil diversity of different populations of Thymus fallax Fisch. & C.A.Mey. collected from some of its habitats in Iran

Abstract

Background: Thymus fallax Fisch. & C.A.Mey. is one of the medicinal plants of the Lamiaceae family, which aerial part contains valuable phytochemical compounds such as thymol and carvacrol. Objective: This study was performed for assessing the essential oil diversity of different populations of Thymus fallax in its habitats. Methods: The populations of Thymus fallax were collected from its natural habitats in Alborz, Tehran, Zanjan, Mazandaran, and North Khorasan provinces. Their essential oils were extracted by hydro-distillation method and the compounds were identified using GC and GC-MS. Results: The result indicated that the essential oil content of populations was on average 1.71 %, the highest percentage of which was observed in the population of Migoun(2.58 %), Chelcheshmeh (2.35 %), and Ghormehdareh (2.25 %), and the lowest was obtained in Dizin (1.05 %) and Ira (1.15 %). Overall, 30 essential oil compounds were identified, comprising 95 % of the total essential oil, of which carvacrol, thymol, p-cymene, and geraniol were the major constituents, accounting for 75 % of the essential oil. Five groups of thyme population were identified using cluster analysis, including the first group with high content of carvacrol, the second group with high content of geraniol, the third group with high content of thymol and carvacrol, the fourth group with high content of thymol, and the fifth group with high content of thymol, carvacrol and geraniol. Conclusion: The high amounts of essential oil, carvacrol and thymol in some populations were valuable results that can be considered in future and breeding studies.

Keywords

• carvacrol
• essential oil
• populations
• thymol
• thymus fallax