Thymbra L. and Satureja L. essential oils as rich sources of carvacrol, a food additive with health-promoting effects

Carvacrol, an oxygenated monoterpene, usually dominates the essential oil of aromatic plants of the Lamiaceae family, such as representatives of the genus Origanum L. (Lamiaceae), and other included genera commonly known as “oregano” spices. According to a significant number of studies, carvacrol exhibits an array of pharmacological and biological properties; it has also been approved by the Federal Drug Administration and Council of Europe as food additive and is considered generally safe for consumption. Nevertheless, not all “oregano” species are rich in carvacrol, depending on various factors and given chemotype. In the framework of our ongoing research on the chemistry and biological activities of aromatic plants found in the Mediterranean Basin and more specifically of Greek endemic species, we investigated the essential oils of Thymbra calostachya (Rech. fil.) Rech. fil., a Greek endemic species growing in Crete, along with Thymbra capitata (L.) Cav., as well as Satureja thymbra L., collected from natural populations in Greece, with the prospect of identifying new candidates for the production of carvacrol-rich cultivars. Apart from a single population, all investigated samples were characterized by the dominance of carvacrol [T. calostachya (Rech. fil.) Rech. fil. 73.6%-78.4%, T. capitata (L.) Cav. 50.4%-78.1%, S. thymbra L. 2.8%-65.2%].