Tabriz University of Medical Sciences Pharmaceutical Sciences 1735-403X 20 1 2014 03 01 Essential Oil Composition, Antioxidant Activity and Total Phenolic Content of Some Lamiaceae Taxa Growing in Northwest of Iran 22 28 EN Mohammad-Reza Delnavazi Farzin Baba-ali Sepideh Soufiabadi Mona Sherafatmand Fariba Ghahremani Saeed Tavakoli Narguess Yassa Journal Article 2014 06 28 Background: Lamiaceae family is one of the main sources of aromatic and medicinal plants. In the present study essential oil constituents, free radical-scavenging activity and total phenolic content of the aerial parts of four Lamiaceae taxa, Ziziphora tenuior (ZT), Scutellaria orientalis subsp. virens (SO), Eremostachys laciniata subsp. iberica (EL) and Phlomis herba-venti subsp. pungens (PH), collected from "Mishu-Dagh" region (Northwest of Iran) were investigated. Methods: GC and GC-MS were applied for the analysis of plants oils. Free radical-scavenging activity and total phenolic content of the plants hydroalcoholic extracts and their polar and non-polar fractions were also evaluated using DPPH and Folin-Ciocalteu methods, respectively. Results: A total of 58 compounds were identified in essential oils, among them 1,8-cineol (19.6%), germacrene D (16.5%), linalool (10.2%) and germacrene D (11.7%) were characterized as main compounds in ZT, SO, EL and PH oils, respectively. In DPPH assay, polar fractions of EL and ZT exhibited considerable free radical-scavenging activity (IC50; 11.0 ± 2.3 and 12.7 ± 2.7 μg ml-1, respectively) in comparison with BHT (IC50; 10.8 ± 2.1 μg ml-1). The former fractions were also found to contain the highest total phenolic content (231.9 ± 9.3 and 214.1 ± 11.3 mg EGA/g, respectively). Conclusion: The present study introduces these four taxa as the plants with terpene rich oils and suggests them as potential sources of free radical-scavenging compounds.