Potential Effect of Acacia arabica on Peste des Petits Ruminants Virus Replication

摘要

An aqueous preparation from Acacia arabica var. indica Benth (Mimosaceae) (locally known as "babul") leaves (BExt) was assessed for its in vifro antiviral activity using peste des petits ruminants virus (PPRV) as a test model in the Vero cell system, Cytopatbic effect (CPE) inhibition, virus titration, cell ELISA, sandwich-ELISA (s-ELISA), and PCR assays were used to determine the antiviral effects (at maximum noncytotoxic concentrations 150 and 200 ug/mL) against PPRV, and in vitro cytotoxicity assays established the relative safety concentration of the BExt for the cells. BExt inhibited viral infectivity drastically in terms of decreased virus titer and antigen load in a dose-dependent manner either when added to cell monolayers postinfec-tion or when preincubated with virus before adsorption on the cells. Inhibition of cell-free and cell-associated PPRV during replication in presence of BExt in Vero cells, using a multistep growth curve experiment, were assessed by s-ELISA. BExt (200 uglmL) completely inhibited PPRV replication in Vero cells that were infected with PPRV at 0.01 multiplicity of infection. Incubation of PPRV with BExt (150 and 200 ug/mL) followed by infection had a virucidal effect on subsequent progeny virus yield by a 3 logio TCID50 reduction. This indicates that active principle(s) of BExt either inactivated the virus or inhibited the viral release. Real-time PCR data based on nucleoprotein gene showed 196.7- and 770.6-fold reduction in the viral load in the presence of BExt concentrations of 150 and 200 uag/mL, respectively, indicating the efficacy of BExt in inhibiting PPRV multiplication. These data suggest that extracts of A. arabica could be a potential natural antiviral agent for management of PPR disease and also a possible addition in the traditional phyto-antiviral repertoire for viral disease control.