Fatih DEMİRCİ, Sümeyye Elif KAHYA
Journal of Research in Pharmacy - 2026;30(4):1148-1156
Recent years, particularly following the COVID-19 pandemic, a significant rise in fatigue, depression, and nervous system disorders was observed. While conventional pharmacotherapy is the standard for neuropsychiatric conditions, the use of herbal preparations is gaining prominence. Within the scope of this study, the potential anxiolytic effects of combined standardized herbal preparations were evaluated using the in vitro monoamine oxidase (MAO) inhibition assays. The essential oil of Lavandula angustifolia Mill. was analyzed and verified by GC/MS, where linalol (22.1%) and linalyl acetate (19.2%) was in compliance with European Pharmacopoeia. Whereas the Humulus lupulus L. flower aqueous ethanol extract contained 0.9% humulone according to the HPLC analyses. In vitro enzymatic assays showed that the H. lupulus extract inhibited MAO-A and MAO-B with IC50 values of 47.7 and 50 ?g/mL, respectively. Where the L. angustifolia essential oil showed IC50 69.4 and 55.1 ?g/mL inhibitions, respectively. Using the checkerboard method, the combination of H. lupulus (1:4 ratio) and L. angustifolia (1:3 ratio) showed 95.5% inhibition of MAO-A, suggesting a syergistic effect, to the best of our knowledge for the first time. These initial experiements suggest that the combinations of lavender oil and hop strobile preparations may be utilized with the potential for development of standardized nervous system targetted phytotherapeutics.
