Chemical composition of essential oils of Grindelia squarrosa (Pursh) Dunal and Grindelia oregana A. Gray

The genus Grindelia (Asteraceae) comprises about 60 species. All are native to North and Central America and chiefly distributed in warm-temperate regions. Several species are cultivated as ornamentals in Europe. Grindeliae herba traditionally is used as an adjuvant for treatment of catarrhs of upper respiratory tract, antispasmodic, expectorant. The essential oil of Grindelia squarrosa (Pursh) Dunal and Grindelia oregana A. Gray cultivated in Romania was isolated by hydrodistillation. The essential oils were analysed by combination of GC and GC/MS. The identification of the constituents was achieved from their retention indices and comparison of their MS data with computer library database and with literature data. The fifty identified constituents accounted 72.1 – 81.3% of the oils. These oils were found to contain α-pinene, β-pinene, limonene, borneol, bornyl acetate and germacrene D as main constituents. The oils obtained from the two species showed small differences in chemical composition. However, menthol, menthone and pulegone were detected only in the essential oil of G. oregano.