Diversity in chemical compositions of essential oil of myrtle leaves from various natural habitats in south and southwest Iran

摘要

Myrtle, Myrtus communis L.(Myrtaceae), an evergreen shrub also known as wild myrtle, has a history of use as a culinary and medicinal plant. To determine the diversity within the species, plant leaves of myrtle were collected in 12 natural habitats in Iran for investigation of chemical constituents in the essential oil. Extraction of the essential oils produced yields ranging from 0.7 to 1.5 m L per100 g dry tissue. An analysis of the oils by GC and GC/MS revealed 40 compounds, constituting 90.1–99.9 % of the essential oils. Chemical constituents varied with the site of sample origin, although the principal essential oil components from all populations, were a-pinene(17.5–37.1 %),1,8-cineole(9.9–29.8 %), linalool(7.0–23.1 %), and a-terpineol(5.3–8.3 %). Limonene(tr, 22.7 %) was a major constituent in three populations. Characterized chemotypes included Chemotype I: a-pinene/1,8-cineole/linalool, Chemotype II: a-pinene/linalool, Chemotype III: a-pinene/1,8-cineole, and Chemotype IV: a-pinene/1,8-cineole/limonene.The main source of variability in chemical composition and oil yield appeared to be differences in environmental conditions and chemotypes as plant populations collected from close geographical areas could be classified in a cluster.