Review on essential oil, extracts composition, molecular and phytochemical properties of Thymus species in Iran

Thymus, which includes around 215 species, is an important genus of the Lamiaceae family due to its production of secondary compounds. It comprises several species which are native to the Mediterranean region and can serve as valuable medicinal plants, because of their biological and pharmacological properties. In fact, the local populations often use it for different medicinal purposes, as expectorant, antiseptic, antispasmodic, carminative, cardiac, antirheumatic, and diuretic. Many natural compounds extracted from Thymus display biological activities, with relevance to essential oils (EOs) which have arouse much interest. Thymus-derived EOs and their components have numerous applications as natural agents in food preservation, while also displaying antibacterial, antifungal, and antiviral properties. They are very interesting worldwide as potential sources of novel antimicrobial compounds to serve as alternatives to treat infectious diseases. However, there is not yet a thorough review of this genus from Iran. The present review was, therefore, conducted to discuss EO components, its biological activity, and to refer the molecular studies performed until present. This review is mainly meant to provide relevant information on the phytochemical features of Iranian Thymus species, with emphasis on EO, providing guidance for the selection of accessions or species with the best chemical profiles.