Green Synthesis of Silver Nanoparticles with Extract of Indian Ginseng and In Vitro Inhibitory Activity against Infectious Bursal Disease Virus Thereof

Infectious bursal disease virus (IBDV) is a serious poultry pathogen responsible for causing major economic losses to the poultry industry globally. The virus is closely related to several other important viral pathogens of fishes, crabs, and mollusks and evolutionarily related to important viral pathogens of humans. Previously, we demonstrated the inhibition of this virus by the extracts of roots of Withania somnifera Dunal, commonly known as Indian ginseng, both in vitro and in vivo. Furthermore, many studies reported the inhibition of diverse types of viruses by nanoparticles of silver. In the present study, we investigated the inhibitory effect of silver nanoparticles obtained by green synthesized with Indian ginseng extract against IBDV. Conditions for the synthesis of silver nanoparticles were optimized, and the nanoparticles thus obtained (WS AgNPs) were characterized physically. Thereafter, the maximum non-cytotoxic dose of these nanoparticles for treating chicken embryo fibroblasts (CEF) was determined. Treatment of IBDV-infected CEF with the WS AgNPs decreased the infective virus titer by >93%, intracellular viral load by >71%, and virus-induced cytopathy by >51%, demonstrating the strong inhibitory effect of the WS AgNPs against IBDV, and encouraging similar applications against related veterinary and human viruses.