Extracts from Valsonectria inflata, a Soil-Derived Fungus, Inhibit Human Coronavirus OC43 Replication

Area of Science:

• Mycology
• Virology
• Natural Product Chemistry

Background:

• Coronaviruses cause significant human diseases, including COVID-19 and the common cold.
• Emerging coronavirus variants necessitate the development of novel therapeutic strategies.
• Fungi are a known source of bioactive compounds, including antibiotics like penicillin.

Purpose of the Study:

• To screen fungal extracts for antiviral activity against human coronavirus.
• To investigate the potential of Valsonectria inflata extract (VIE) as an antiviral agent.

Main Methods:

• Screening of fungal extracts for antiviral properties.
• Western blot analysis to assess viral protein expression.
• Quantitative RT-PCR and plaque assays to measure viral production.
• Scanning electron microscopy (SEM) for visualizing viral particles.
• High-resolution electrospray ionization mass spectrometry (HR-ESI-MS) for chemical analysis.

Main Results:

• Valsonectria inflata extract (VIE) demonstrated significant antiviral effects against human coronavirus.
• VIE treatment led to decreased coronavirus protein expression and reduced viral production.
• SEM confirmed a reduction in infectious viral particle formation.
• VIE treatment ameliorated coronavirus-induced cytotoxicity.
• VIE contains secondary metabolites, including terpenoids.

Conclusions:

• Valsonectria inflata extract (VIE) exhibits potent antiviral activity against human coronavirus.
• VIE represents a promising candidate for developing new antiviral therapies against coronaviruses.
• The identified secondary metabolites in VIE may contribute to its antiviral properties.