The Essential Oil Composition in Commercial Samples of Verbena officinalis L. Herb from Different Origins

The key objective of this study was to determine the yield and chemical composition of eight commercial samples and one collected sample of common vervain (Verbena officinalis L.) herb essential oil (EO) originating from seven different countries, and subsequently, to assess its potential for treating anxiety and depression. According to GC-MS analysis, 90 compounds were identified, 49 of which were discovered for the first time in V. officinalis EO. The plants with the highest oil content are from Greece (4.7 mL/kg) and South Carolina, USA (5.2 mL/kg). The chemical markers for the studied chemotypes of EO of V. officinalis are the terpenoids o-cymene, p-cymene, L-carvone, thymol, carvacrol, α-curcumin, hexahydrofarnesyl acetone, phytol, (E)-β-ionone, and phenylpropene anethole. The chemotype from the UK demonstrated the greatest affinity to the continuum under study; it has the highest levels of similarity—85.2% with the chemotype from Greece, 69.4% with the chemotype from the USA, 68.2% with the chemotype from Estonia (2), 58.7% with the chemotype from Germany, and 58.6% with the chemotype from Hungary. The chemotypes identified have the potential for use in the treatment of anxiety and depression.