Essential oil analysis of Teucrium libanitis and T. turredanum by GC and GC–MS

The chemical composition of the six essential oils obtained from Teucrium libanitis and Teucrium turredanum collected at different localities was analysed by GC and GC–MS. Fifty‐three constituents were identified. The oil of T. libanitis is characterized by the monoterpene α‐pinene (9.9–21.2%) and the sesquiterpene δ‐cadinene (5.3–9.7%), while that of T. turredanum had a higher content of sesquiterpenoids: β‐caryophyllene (15.6–32.6%), α‐humulene (4.7–10.1%) and β‐bisabolol (6.4–8.3%), and a lower percentage of monoterpenoids (<1%). A multivariate procedure (hierarchical clustering) for detecting natural grouping established that T. libanitis and T. turredanum constitute two independent taxa.