Articles
ENVIRONMENTAL CONDITIONS AND ESSENTIAL OIL DIVERSITY OF NATIVE THYMUS PULEGIOIDES POPULATIONS IN HIGHLANDS OF HUNGARY AND IN THE CARPATHIANS
Article number
955_6
Pages
65 – 71
Language
English
Abstract
Occurrence, environmental factors and essential oil properties of T. pulegioides populations have been surveyed in highlands of Hungary and in the East Carpathians.
Natural populations were found in habitats where base rock (andesite, rhyolite, Pannonian sandstone or salt diapire) facilitated the development of soils with acidic or almost neutral character, like erubase, podzol, meadow or bare soils.
From a coenological point of view, T. pulegioides is an element of mountain meadows and hayfields, growing on silicate rocky grasslands or in greenweed-oak forests.
Almost all dried flowering shoot samples met the requirements of the Pharmacopoeia Hungarica (2004: min. 0.3 ml/100 g essential oil), with values ranging between 0.01 and 1.50 ml/100 g (mean: 0.41 ml/100 g). Six new chemotypes have been described: carvacrol/thymol; carvacrol/thymol metylether/γ-terpinene; geranial/linalyl-acetate/neral/linalool; p-cymene/spathulenol/geraniol; β-caryophyllene /thymol/germacrene D; germacrene D/β-caryophyllene/α- and β-farnesene/ spathulenol.
We show here for the first time T. pulegioides plants with high thymol and carvacrol contents as well as other chemotypes accumulating high proportions of either thymol methylether, germacrene D, spathulenol or farnesene.
Moreover, we have also pointed out the role of sesquiterpenes in the formation of these chemotypes.
Correlations have also been found between ecological circumstances and chemotype patterns.
With optimal environmental conditions (humid mountain climate), the presence of monoterpene phenolic or lemon scented chemotypes could be determined, while on exposed rock surfaces, the dominance of sesquiterpenes and lower level of volatiles were prevalent.
Regarding plant communities, the volatile oil content was lower and the linalool ratio was higher in a steppe slope than in the neighbouring mountain hayfields (near Sovata, Transylvania).
Natural populations were found in habitats where base rock (andesite, rhyolite, Pannonian sandstone or salt diapire) facilitated the development of soils with acidic or almost neutral character, like erubase, podzol, meadow or bare soils.
From a coenological point of view, T. pulegioides is an element of mountain meadows and hayfields, growing on silicate rocky grasslands or in greenweed-oak forests.
Almost all dried flowering shoot samples met the requirements of the Pharmacopoeia Hungarica (2004: min. 0.3 ml/100 g essential oil), with values ranging between 0.01 and 1.50 ml/100 g (mean: 0.41 ml/100 g). Six new chemotypes have been described: carvacrol/thymol; carvacrol/thymol metylether/γ-terpinene; geranial/linalyl-acetate/neral/linalool; p-cymene/spathulenol/geraniol; β-caryophyllene /thymol/germacrene D; germacrene D/β-caryophyllene/α- and β-farnesene/ spathulenol.
We show here for the first time T. pulegioides plants with high thymol and carvacrol contents as well as other chemotypes accumulating high proportions of either thymol methylether, germacrene D, spathulenol or farnesene.
Moreover, we have also pointed out the role of sesquiterpenes in the formation of these chemotypes.
Correlations have also been found between ecological circumstances and chemotype patterns.
With optimal environmental conditions (humid mountain climate), the presence of monoterpene phenolic or lemon scented chemotypes could be determined, while on exposed rock surfaces, the dominance of sesquiterpenes and lower level of volatiles were prevalent.
Regarding plant communities, the volatile oil content was lower and the linalool ratio was higher in a steppe slope than in the neighbouring mountain hayfields (near Sovata, Transylvania).
Authors
Z. Pluhár, S. Sárosi , H. Simkó
Keywords
wild thyme, mountain thyme, volatile composition, variability, soil conditions, drug quality, gas chromatography
Online Articles (54)