Nutraceutical prospects of Houttuynia cordata against the infectious viruses.

The novel enveloped β-coronavirus SARS-CoV-2 (COVID-19) has offered a surprising health challenge all over the world. It develops severe pneumonia leading to acute respiratory distress syndrome (ARDS). Like SARS-COV-2, other encapsulated viruses like HIV, HSV, and influenza have also offered a similar challenge in the past. In this regard, many antiviral drugs are being explored with varying degrees of success to combat the associated pathological conditions. Therefore, upon scientific validation & development, these antiviral phytochemicals can attain a futuristic nutraceutical prospect in managing different encapsulated viruses. Houttuynia cordata (HC) is widely reported for activities such as antioxidant, anti-inflammatory, and antiviral properties. The major antiviral bioactive components of HC include essential oils (methyl n-nonyl ketone, lauryl aldehyde, capryl aldehyde), flavonoids (quercetin, rutin, hyperin, quercitrin, isoquercitrin), and alkaloids (norcepharadione B) & polysaccharides. HC can further be explored as a potential nutraceutical agent in the therapy of encapsulated viruses like HIV, HSV, and influenza. The review listed various conventional and green technologies that are being employed to extract potent phytochemicals with diverse activities from the HC. It was indicated that HC also inhibited molecular targets like 3C-like protease (3CLPRO) and RNA-dependent RNA polymerase (RdRp) of COVID-19 by blocking viral RNA synthesis and replication. Antioxidant and hepatoprotective effects of HC have been evident in impeding complications from marketed drugs during antiviral therapies. The use of HC as a nutraceutical is localized within some parts of Southeast Asia. Further technological advances can establish it as a nutraceutical-based functional food against pathogenic enveloped viruses like COVID 19.