Antiviral activity of Indian medicinal plants against pandemic 2009 Influenza (H1N1) virus

Abstract

Introduction: Crude extracts of leaves and stems of 16 Indian medicinal plants were tested for their antiviral
activity against 2009 pandemic influenza virus (H1N1) by neutralization, hemagglutination inhibition, and
cytopathic effect reduction assay. Materials and Methods: Seventeen medicinal plants were extracted to prepare
50% ethanol and aqueous extract. These 34 extracts were tested for anti-influenza properties at their non-toxic
concentrations. Results: On the basis of microneutralization assay, both 50% ethanolic, aqueous extracts of
Rhododendron arboreum and Pulmonaria longifolia and 50% ethanolic extracts of Rollinia parviflora showed
better potential (IC50 value of 1.93, 3.35, and 3.75 μg/ml, respectively). In cytopathic effect reduction assay, Salix
alba aqueous and 50% ethanol extracts of R. arboreum and Urtica dioica (IC50 value of 0.980, 2.14, and 2.33 μg/ml,
respectively) demonstrated anti influenza activity. The results suggest that selected plant extracts have a protective
effect against pandemic H1N1 virus infection. Conclusion: The results indicates that the experimental plants
demonstrate promising antiviral activity and could prove effective alternate against conventional allopathic drugs.