Phytosynthesized Nanoparticles Against Viral Diseases: Current Updates

Abstract

Advancements in nanomedicine have effectively overcome the issues of solubility, absorption, and cytotoxicity of conventional drugs. In recent years, phytoproducts rich in bioactive constituents have been exploited as green-, herb-, or phytosynthesized metal or nonmetal nanocarriers. Of these, alkaloids, flavonoids, polyphenols, sterols, lignans, tannins, and saponins efficiently contribute to the enhanced stability of such nanocarriers or nanoparticles by reducing metal ions. In addition, phytosynthesized silver and gold nanoparticles have received much interest due to their less hazardous, eco-friendly, and cost-effective properties. Owing to these properties, phytosynthesized silver and gold nanoparticles also have been developed as effective antiviral drug delivery carriers against human immunodeficiency virus, herpes simplex virus, influenza virus, dengue virus, chikungunya virus, hepatitis B virus, bovine diarrhea virus, and foot and mouth disease virus infections. Although experimental studies have shown that such phytonanoparticles can inhibit viral replication in infected cells, the underlying mechanism of their antiviral activities is poorly understood. Importantly, compared to herbal antivirals or metal-based antiviral nanoparticles, the novel approach of phytosynthesis of antiviral nanoparticles seems to be in its infancy. In view of the emerging viral outbreaks and pandemics like coronavirus disease 2019, this area of drug research needs special attention.