Plant-based compounds with antiviral properties against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been identified in Aframomum melegueta through computational models. The seed extract have been traditionally used to treat different illnesses. In this study, ethanolic extracts were prepared for six commercial samples of A. melegueta seeds. Antiviral activity was tested using the XTT cytotoxicity assay and cell-based SARS-CoV-1 and 2 pseudoviral models. The presence of gingerols and other non-volatile components in the seed extracts was determined using an Agilent 1290 UPLC/DAD in tandem with an Agilent 6546 QTOF-MS. Our results showed selective antiviral activity with TI values as high as 13.1. Fifteen gingerols were identified by chromatographic analysis, with 6-gingerol being the dominant component in each seed extract. A combination of 6-gingerol with techtochrysin, previously identified in computational models as a potential active ingredient against SARS-CoV-2, demonstrated additive antiviral activity with CI values between 0.8715 and 0.9426. We confirmed the antiviral activity of A. melegueta predicted through computational models and identified a different compound, 6-gingerol, as a potential active ingredient.
Keywords: Antiviral; CC50, half-maximal cytotoxic concentration; CI, Combination Index; COVID-19, Coronavirus disease 2019; EC50, half-maximal effective concentration; Gingerols; METLIM, Metabolomics Database and Library; PCDL, comprehensive database of metabolites that includes MS/MS spectra; Phytotherapy; PsV, pseudovirus; QTOF/MS, quadrupole technologies with a time-of-flight mass analyser; SARS-COV-2; SARS-CoV-2, Severe Acute Respiratory Syndrome Coronavirus 2; SE, Seed Extract; TI, Therapeutic index; UPLC/DAD, ultra-performance liquid chromatography method with diode array detection; XTT, 2,3-Bis-(2-Methoxy-4-Nitro-5-Sulfophenyl)-2H-Tetrazolium-5-Carboxanilide; hACE-2, human angiotensin-converting enzyme 2.
© 2021 The Author(s).