A quantitative PCR assay for antiviral activity screening of medicinal plants against Herpes simplex 1

Abstract

Herpes simplex virus one is one of the most prevalent pathogens worldwide. Strains resistant to current treatment have been reported, so it is necessary to search for new antiviral molecules. The most common method to quantify antiviral activity from natural products is the plaque reduction assay, a technically demanding method. In order to provide a simple alternative to this method, we have established a procedure for viral quantification by qPCR, and coupled with a cytotoxicity evaluation system using resazurin. In this way, it is possible to obtain both the estimation of cytotoxicity and the antiviral activity simultaneously, allowing rapid screening of plant extracts. Ten out of twenty-eight Paraguayan medicinal plant extracts evaluated using this method showed antiviral activity, and the EC₅₀, CC₅₀, and SI values were calculated for each extract. Our experience supports the employment of the described method for a rapid identification of plant extracts with antiviral activity.

Graphical Abstract

Keywords:

• Antiviral screening
• HSV-1
• plant extracts
• qPCR

Acknowledgments

We want to thank Nidia Benitez for reviewing and commenting on the manuscript. This study was performed within the project PINV 14-149 of CONACYT funded by the PROCIENCIA Program with resources from FEEI of FONACIDE, Paraguay.

Disclosure statement

No conflict of interest was reported by the authors.

Additional information

Funding

This study was supported by the project PINV14-149 from CONACYT, through the PROCIENCIA Program with resources from FEEI of FONACIDE-Paraguay.