An Anisole Derivative in the Essential oil of Wurfbainia schmidtii with Virucidal Activity Against SARS-CoV-2 and Anti-Inflammatory Properties

Abstract

Objectives: Essential oils from many plants have been reported to have anti-inflammatory activity. However, essential oil of Wurfbainia schmidtii leaves has never been reported for anti-inflammatory activity. Moreover, previous works on the essential oil compositions of W. schmidtii (synonyms Amomum biflorum and Amomum schmidtii) reported varied compositions in its oils. This work aims at investigating the essential oil compositions of W. schmidtii and its anti-inflammatory activity, as well as virucidal activity against SARS-CoV-2 virus. Methods: The composition of W. schmidtii essential oil was analyzed by gas chromatography-mass spectrometry (GC-MS) technique. A crude hexane extract of W. schmidtii was separated by chromatographic method, giving a major phenylbutanoid, trans-p-(l-butenyl)-anisole (1), whose structure was elucidated by analysis of 1D and 2D 1H nuclear magnetic resonance (NMR) spectra. Anti-inflammatory activity of the essential oil and the major compound 1 was evaluated, and virucidal activity of against SARS-CoV-2 virus was assessed for compound 1. Results: A major component in W. schmidtii essential oil was found to be trans-p-(l-butenyl)-anisole (1), accounting for 88.69%, and it exhibited virucidal activity against SARS-CoV-2 with EC50 value of 119.60 μM. W. schmidtii essential oil and the major compound 1 exhibited anti-inflammatory activity with the IC50 values of 0.0282 mg/mL and 12.74 μM, respectively. Conclusion: trans-p-(l-Butenyl)-anisole (1) was the major compound in the essential oil of W. schmidtii, and it displayed anti-inflammatory and virucidal activities. The essential oil of W. schmidtii showed anti-inflammatory activity.