Planta Med 2013; 79 - PN57
DOI: 10.1055/s-0033-1352400

Bioprospecting diverse plant species for antiviral agents against upper respiratory tract infections

CE Mair 1, U Grienke 1, S von Grafenstein 2, J Kirchmair 3, KR Liedl 2, M Schmidtke 4, JM Rollinger 1
  • 1University of Innsbruck, Center for Molecular Biosciences Innsbruck, Institute of Pharmacy/Pharmacognosy, Innrain 80 – 82, 6020 Innsbruck, Austria
  • 2University of Innsbruck, Center for Molecular Biosciences Innsbruck, Institute of General, Inorganic and Theoretical Chemistry, Innrain 80 – 82, 6020 Innsbruck, Austria
  • 3Unilever Centre for Molecular Informatics, Department of Chemistry, Lensfield Road, Cambridge, CB2 1EW, UK
  • 4Jena University Hospital, Department of Virology and Antiviral Therapy, Hans-Knoell-Straße 2, 07745 Jena, Germany

Upper respiratory tract infections (URIs) are caused by various bacteria and viruses. In this work, we focused on the identification of natural constituents with antiviral activity on human rhinovirus (HRV2), a predominant cause of the common cold, influenza virus A and coxsackie virus (CVB3), both of them being responsible for more severe forms of URIs.

Starting from a literature survey to explore knowledge from folk medicine, 66 plant species of interest were identified. The selection focuses on the flora of the Alpine region with Lamiaceae, Apiaceae and Asteraceae representing the most prominent families.

Following the acquisition and collection of the selected plants, the obtained extracts were tested for their antiviral potential against the three viruses in cytopathic effect (CPE) inhibition assay. About 12% of the extracts had an IC50 lower than 50 µg/mL for influenza virus A/HK/68 in MDCK cells. A comparable ratio of active extracts was found for HRV2, and 8% of all extracts showed activity for CVB3, the latter two being tested in HeLa cells. Of all active extracts, 31% inhibited two and even 8% all three distinct viruses.

In addition to these experimental investigations, a structure-based computational approach was followed, aiming to support the interpretation of ethno-pharmacological data and guide isolation. As a preliminary result, five out of the 66 plant species were found to contain constituents that were predicted in silico to be active on influenza virus neuraminidase and nucleoprotein, as well as the HRV capsid protein 1. In the course of the experimental evaluation of these five extracts, all of them were confirmed to exhibit significant antiviral activity, affirming the potential of this bioprospecting approach in finding valuable starting points for target-based drug discovery.

This work is supported by the Austrian Science Fund (FWF P24587 & P23051) and the European Social Fund (ESF and TMWAT Project 2011 FGR 0137).