Volatile Components Analysis, Total Phenolic, Flavonoid Contents, and Antioxidant Activity of Phlomis Species Collected from Jordan

AbstractIn this study, the composition of the essential oil, flavonoid and phenolic contents, and the antioxidant activities of three Phlomis species from Jordan (P. viscosa Poiret., P. platystegia Post. and P. brachyodon Boiss.) were examined. The essential oil from fresh and air dried aerial parts of these Phlomis species was obtained by hydrodistillation and analyzed by GC-MS. Germacrene B, E-caryophyllene and γ-muuroleneas were the major constituents of the oil from P. viscosa, while viridiflorol, β-eudesmol, Linalool and γ-cadieneneas dominated in P. platystegia, and γ-muurolene, α-humulene, γ-himachalene and Linalool were the chief components of the oil from P. brachyodon. Comparatively, the different oils extracted from the air-dried parts of the three Phlomis species showed less content in monoterpene and sesquiterpene hydrocarbons and higher amounts of oxygenated monoterpenes and sesquiterpenes than the oils from the same fresh areal parts. The total phenol and flavonoid contents from crude fract...