NVEO 2017, Volume 4, Issue 4 CONTENTS REVIEWS 1. Biological properties of essential oils and volatiles: Sources of variability / Pages: 1-13 A. Cristina Figueiredo 2. Systematic and Biogeographic overview of Lamiaceae in Turkey / Pages: 14-27 Ferhat Celep, Tuncay Dirmenci 3. Stamen construction, development and evolution in Salvia s.l. / Pages: 28-48 Regine Claßen-Bockhoff ARTICLES 1. TLC-GC/MS Method for identifying and selecting valuable essential Oil Chemotypes from Wild Populations of Mentha longifolia L. / Pages: 49-61 Juan Antonio Llorens-Molina, Vicente Castell, Sandra Vacas, Mercedes Verdeguer 2. Chemical composition and antioxidant activity of essential oils of six Lamiaceae plants growing in Southern Turkey / Pages: 62-68 Hasan Maral, Murat Türk, Tuncay Çalışkan, Saliha Kırıcı Nat. Volatiles & Essent. Oils, 2017: 4(4): 1-13 Figueiredo A.C. REVIEW Biological properties of essential oils and volatiles: Sources of variability A. Cristina Figueiredo* Centro de Estudos do Ambiente e do Mar (CESAM Lisboa), Faculdade de Ciências da Universidade de Lisboa, Centro de Biotecnologia Vegetal (CBV), Edifício C2, Campo Grande, 1749-016 Lisboa, PORTUGAL *Corresponding author. E-mail:
[email protected] Abstract Essential oils are a specific type of extracts that result either from hydro-, steam- or dry-distillation from any part of a duly identified botanical species, or by a mechanical process without heating, called expression, from the epicarp of Citrus fruit species. Any other type of extraction may provide a more, or less, volatiles-rich extract, but it is not an essential oil. Essential oils, per se, do not exist in the plant, since they result from a specific extraction procedure.