Unraveling the bioenergy production and electron transport characteristics of processed Rheum palmatum L. for antiviral drug development

To bridge western and traditional Chinese medicine, research in Chinese medicinal herbs has become an increasing trend for discovering new effective antiviral drugs. In addition, this pioneer study disclosed that synergistic interactions of electron-mediating contents in herbal medicines through electrochemical catalysis of electron shuttles could trigger effective disease treatment via electron transport stimulation as the platform of microbial fuel cells (MFCs) indicated. Hence, this study first attempted to decipher the bioenergy-assisted action of R. palmatum L. for antiviral assessment. Several processing methods can be performed to maximize phytoconstituent extraction and efficiency that can influence the chemical profile and bioactivity of herbal samples. To generate a comparative analysis, R. palmatum L. roots are subjected to several processing methods and are evaluated through phytochemical screening, antioxidant activity, high-performance liquid chromatography analysis, and dual-chambered-MFCs for bioenergy production. Molecular docking analysis of marker substances was also employed to establish the potential of R. palmatum L. for antiviral drug development. Ethanol extracts are revealed to be toxic for MFCs despite having increased phenolic compounds. Overall, vinegar-processed Rheum palmatum water extracts exhibited the highest bioenergy-stimulating capabilities and antioxidant activity. Furthermore, rhein from the same extract was found to exhibit strong binding affinities towards Flaviviridate viruses and can potentially inhibit NS5B polymerase from the Hepatitis C Virus. This study clearly suggests the potential of R. palmatum L. roots as a promising herb for antiviral drug development. This work also provided a novel protocol for prescreening candidate species for antiviral drug development.