The volatile profile of the Sicilian Centaurea tauromenitana Guss. (= Colymbada tauromenitana (Guss.) Holub) and its comparison with other Colymbada species

Essential oils (EOs) from the genus Centaurea are renowned in traditional medicine for their pharmacological properties. Despite the widespread use of Centaurea sp., there is limited knowledge about Centaurea belonging to the former genus Colymbada. The volatile profile of EOs from whole and separated aerial parts of Centaurea tauromenitana Guss. also known as Colymbada tauromenitana from Sicily (Italy), not previously investigated, was evaluated by GC–MS, identifying 72 compounds. All the samples showed a composition principally characterized by oxygenated (23.1–43.8%) and non-oxygenated (35.4–49.9%) sesquiterpenes, with germacrene D (24.4–30.4%), α-cadinol (8.4–29.1%), ledene oxide(II) (5.1–6.6%), τ-cadinol (4.7–5.6%), β-caryophyllene (4.1–4.2%), and δ-cadinene (1.8–4.7%) as the main compounds. To evaluate the similarity between C. tauromenitana and samples of the former genus Colymbada, Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) were done. Centaurea tauromenitana EOs did not exhibit similarities with other species, with the exception of Colymbada immanuelis-loewii and Colymbada spruneri.