Planta Med 2013; 79 - PK41
DOI: 10.1055/s-0033-1352301

Optimisation of Echinacea purpurea extraction and processing to yield high potency antiviral activity

S Vimalanathan 1, R Schoop 2, JB Hudson 1
  • 1University of British Columbia, Department of Pathology and Laboratory Medicine, Faculty of Medicine, Vancouver, BC, V6T 2B5, Canada.
  • 2A. Vogel Bioforce AG, Medical Department, Roggwil, Switzerland.

Introduction

Antiviral and anti-inflammatory activities are important for the prevention and treatment of respiratory tract infections. These activities can be found in the herbal medicinal plant Echinacea purpurea (EP). However different commercial preparations of EP vary greatly in chemical composition and the manufacturing procedures used, and consequently differ significantly in their antiviral potencies. As a result, there is no standard procedure for the preparation of consistent high potency extracts. In this study we evaluated different types of EP extracts for relative antiviral activities.

Antiviral activity

Ethanol is an ideal solvent to isolate the antiviral principles from E. purpurea (1). We separately investigated ethanol extracts (65% V/V) of roots, herb (aerial part without flowers), flower heads and the petals. Minimal inhibitory concentrations (MIC) were measured quantitatively by means of standard plaque assays with influenza virus type A, H3N2 (1). No antiviral activity was found in the roots and the petals (MIC > 1 mg/ml); but extracts of the herb and of the flower heads were active (MIC < 26.5 µg/ml). In addition there was a substantial difference between the freshly processed herb providing tinctures with MIC < 2.3 µg/ml in comparison to dried herb tincture with MIC equal to 16.8 µg/ml.

Anti-inflammatory activity

Previous studies have demonstrated the anti-inflammatory potential of alkylamides that are enriched in roots of Echinacea species. Thus a combination of herb and root tinctures, prepared from freshly harvested plants, would provide the full spectrum of pharmacological activities for successful cold management.

Conclusion

Ethanol extracts from E. purpurea herb and roots have distinct antiviral and anti-inflammatory potential. In order to obtain optimal benefits of EP, it is desirable to use both herb and root components, derived from freshly harvested plants.

References:

[1] Vimalanathan S, et al. (2005). Pharm. Biol 12;43(9):740 – 745.