IN VITRO ANTI-VIRAL ACTIVITY OF CENTELLA ASIATICA L., CURCUMA LONGA L. AND STROBILANTHES CRISPUS L. AGAINST HERPES VIRUS.

Abstract

Extracts of three different plant species; Curcuma longa L., Centella asiatica L. and Strobilanthes crispus L. which are used widely in Malaysian traditional medicine are investigated for antiviral activity against alpha-herpesvirus (pseudorabies virus).  The methanol extract (ME) and aqueous extract (AE) were tested in three cell lines; African Green Monkey Kidney (Vero), Baby Hamster Kidney (BHK) and Rabbit Kidney (RK) cells, at non-cytotoxic concentrations.  Assays were developed to determine the characteristics of anti pseudorabies virus (PrV) activities, as anti-viral attachment, anti-prophylactic and /or virucidal.  All plant extracts showed marked virucidal ability and considerable prophylactic and anti-viral attachment activities.  Plant ME always showed better antiviral activities than plant AE.  Curcuma longa L. showed a better virucidal and prophylactic effect (with more than 70% cell viability at 25 µg/ml) for ME and AE.  While Centella asiatica L. and Strobilanthes crispus L. were most active as anti-viral attachment agent with percent cell viability up to 60%.  It was also found that the anti-viral activities were varies in different cell lines tested.  Therefore, the extracts of all three plant species exhibited anti PrV and they could be further investigated for medical purposes.