Phytochemical evaluation of different populations of Tanacetum pinnatum Boiss. in natural habitats using multivariate methods

Tanacetum pinnatum Boiss. is a perennial plant native to Iran belonging to the Asteraceae family. Which has been used to treat migraine, rheumatism and anti-inflammatory diseases. In this study, phytochemical charchterisic of different populations of T. pinnatum in natural habitats was evaluated by multivariate methods. First, the aerial parts of plant in blooming were collected from Tehran, Alborz, Hamedan and Kermanshah provinces in mid-June to mid-August 2016. The essential oils were extracted by hydro-distillation clevenger device and were analysed by using GC/MS. The results were showed that the effect of population on leaf and flower essential oil was significant (P<0.01) which seems to be due to geographical factors and type of climate. According to the results, 50 compounds were identified in the flower and leaf essential oils of the populations, of which 13 compounds had the highest frequency among the populations and the highest percentage in the leaf and flower essential oils. Based on the principal component analysis and cluster analysis, populations 1, 2, 9, 3 and 5 had the highest composition of flower essential oil, while populations 4, 8 and 10 had the weakest values for most essential oil compounds. Populations 6, 7, 11 and 12 also had moderate amounts of compounds in flower essential oil. However, for leaf essential oil, populations 1, 2, 6, 3, 5 and 10 had the highest essential oil composition, while population 4 had the weakest values for most essential oil compounds and only had a high amount of cubenol. Populations 9, 12, 7, 8 and 11 also had moderate amounts of compounds in leaf essential oil. Population grouping based on their phytochemical assessment did not match their geographical distribution. However, areas with higher E, Z-geranyl acetate،ß-eudesmol and cubenol levels in flowers and leaves had average annual rainfall and higher altitude, average sunshine, and lower annual temperatures (populations 4 and 1). While in areas where populations had higher levels of α-cadinene in flowers, they had the highest average relative humidity, the lowest rainfall and annual temperature. Population 1 had the highest amount of flower ß-eudesmol and was one of the populations that showed a positive correlation between the amount of flower and leaf essential oil and essential oil components. As a result, the best population in the natural habitat was population 1.