Chemical Composition and Antimicrobial Activity of the Essential Oils from the Flower, Leaf, and Stem of Senecio pandurifolius

The essential oils from the fresh flower, leaf, and stem of Senecio pandurifolius (Asteraceae) were isolated by hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. A total of forty-five, sixty, and forty-two compounds were identified, constituting over 90.1 %, 88.0%, and 89.0% of oil composition of the flower, leaf, and stem of S. pandurifolius , respectively. The chemical profile reveals the dominance of sesquiterpene hydrocarbons (flower: 42.4%, leaf: 43.4%, stem: 52.3%) . The main components of essential oils own to S. pandurifolius were α- cuprenene (30.7%) in flower, α­- zingiberene (16.1%) in leaf and γ -curcumene (14.9%) in stem. Terpene related compounds were in minor amounts in all parts (flower: 1.4%, leaf: 1.5%, stem: 1.9%) of the S. pandurifolius . Also there was no monoterpene hydrocarbons and oxygenated monoterpenes in the essential oil of the stem. In addition, antimicrobial activities of the essential oils of S. pandurifolius were investigated. The oils showed activity against Gram positive bacteria, mycobacterium and fungi, but not Gram negative bacteria. A high antimycobacterial activity was observed with leaf essential oil, which deserves further investigation to determine its active components.