Effect of Seasonal Variation on the Composition of the Essential Oil of Solidago canadensis Cultivated in Egypt

Abstract

The hydrodistilled essential oils of the fresh flowers and the remaining green aerial parts of Solidago canadensis L., family Asteraceae, recently introduced into Egypt were investigated by GC-MS analysis. A comparative study on the composition of the essential oils obtained in the four seasons of the year was carried out to assess the effect of seasonal variation on the collected oil samples. The major compounds detected in the oil samples of all seasons were germacrene D (9.86-29.47 %), α-pinene (3.38-29.17 %), γ-cadinene (0.39-20.36 %), myrecene (2.98-13.74 %) and limonene (4.81-11.47 %). Summer samples contained the highest percentage of monoterpene hydrocarbons, while winter samples showed the highest percentage of sesquiterpene hydrocarbons. Oil samples collected in summer and winter showed potential cytotoxic activity against human liver, breast and cervix carcinoma; Hepg2, MCF7 and Hela respectively. Winter samples showed a relatively higher cytotoxic activity compared to the summer samples.