Essential Oil Composition of Nigella sativa Seeds from Different Populations of Iran

Phytochemical diversity of eight populations of Nigella sativa, grown in different regions of Iran was investigated for their essential oil (EO) composition. The hydrodistilled EO was analyzed using GC-FID and GC-MS. In total, 30 constitutes were identiued displaying more than (88.42-95.32 %) of the total oil composition. Results indicated that the major components of all populations were p-cymene (18.46-52.64 %), alpha-thujene (4.5-10.23 %), alpha-terpineol (5.11-9.72 %), thymoquinone (0.14-9.2 %), longifolene (3.07-8.34 %) and carvacrol (0.87-5.19 %). Principal component analysis (PCA) was used to identify possible relationships between EO composition and geographical locations of the plant. Notably, four groups of Iranian N. sativa populations were determined according to the major components. The observed changes might be due to different geographical factors such as climate conditions, season at the time of collection, stage of development, occurrence of chemotypes, and other culture conditions. This is the first study on EOs of N. sativa collected from different parts of Iran, leading to the first report on its germplasm. The highest thymoquinone content was observed in Abarkooh which can be used for further purification.