Abstract

Seasonal variations of the essential oil of Origanum syriacum were analysed by GC/MS. Twenty five components were identified, independent of season, among which thymol was the main component with 46.70% in the summer and p-cymene was the main component with 62.18% in the early spring. From the other compounds occurred in lower amounts, γ–Terpinene ranged from 0.63 - 19.08% and its maximum level was observed in summer, α–terpinene varied between 0.67 - 4.85% and the maximum level detected in summer season, carvacrol values ranged from 0.73 - 8.90% with the maximal value spring. To obtain favourable phenol content of the oil, O. syriacum should be harvested in summer months.

Key words: Origanum syriacum, seasonal variation, essential oil.