The Essential Oil of Balsamorhiza sagittata from Southwestern Idaho: Chemical Composition and Enantiomeric Distribution

Background/Objective: Arrowleaf balsamroot ( Balsamorhiza sagittata (Pursh) Nutt., Asteraceae) is a conspicuous forb growing in open hillsides and prairies at mid to upper elevations in the Intermountain West and Rocky Mountain regions. The plant is important forage for deer and elk and several Native American tribes used arrowleaf balsamroot as food and medicine. The volatile phytochemicals of B. sagittata have not been previously examined. Methods/Results: Nine individual samples of B. sagittata were collected, the essential oils obtained by hydrodistillation using a Likens-Nickerson apparatus in yields of 0.069-0.956%, and the essential oils analyzed by gas chromatographic techniques (GC-MS, GC-FID, and chiral GC-MS). The major components in the leaf essential oil of B. sagittata were (−)-germacrene D (10.8-34.5%), (+)-β-phellandrene (6.4-19.4%), (−)-( E)-β-caryophyllene (1.4-15.0%), and ( E)-β-ocimene (3.1-8.4%). Conclusion: There was modest variation in composition or yield with respect to geographical location or elevation in the samples from southwestern Idaho, but comparison with essential oils from locations outside of Idaho should more completely define the volatile phytochemistry of this plant.