The continuing cases of COVID-19 due to emerging strains of the SARS-CoV-2 virus underscore the urgent need to develop effective antiviral technologies. A crucial aspect of reducing transmission of the virus is through environmental disinfection. To this end, a nanotechnology-based antimicrobial platform utilizing engineered water nanostructures (EWNS) was utilized to challenge the human coronavirus 229E (HCoV-229E), a surrogate of SARS-CoV-2, on surfaces. The EWNS were synthesized using electrospray and ionization of aqueous solutions of antimicrobials, had a size in the nanoscale, and contained both antimicrobial agents and reactive oxygen species (ROS). Various EWNS were synthesized using single active ingredients (AI) as well as their combinations. The results of EWNS treatment indicate that EWNS produced with a cocktail of hydrogen peroxide, citric acid, lysozyme, nisin, and triethylene glycol was able to inactivate 3.8 logs of HCoV-229E, in 30 s of treatment. The delivered dose of antimicrobials to the surface was measured to be in pico to nanograms. These results indicate the efficacy of EWNS technology as a nano-carrier for delivering a minuscule dose while inactivating HCoV-229E, making this an attractive technology against SARS-CoV-2.
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Inactivation Mechanism and Efficacy of Grape Seed Extract for Human Norovirus Surrogate
ABSTRACT Proper disinfection of harvested food and water is critical to minimize infectious disease. Grape seed extract (GSE), a commonly used health supplement, is a mixture of plant-derived polyphenols. Polyphenols possess antimicrobial and antifungal properties, but antiviral effects are not well-known. Here we show that GSE outperformed chemical disinfectants (e.g., free chlorine and peracetic acids) in inactivating Tulane virus, a human norovirus surrogate. GSE induced virus aggregation, a process that correlated with a decrease in virus titers. This aggregation and disinfection were not reversible. Molecular docking simulations indicate that polyphenols potentially formed hydrogen bonds and strong hydrophobic interactions with specific residues in viral capsid proteins. Together, these data suggest that polyphenols physically associate with viral capsid proteins to aggregate viruses as a means to inhibit virus entry into the host cell. Plant-based polyphenols like GSE are an attractive alternative to chemical disinfectants to remove infectious viruses from water or food. IMPORTANCE Human noroviruses are major food- and waterborne pathogens, causing approximately 20% of all cases of acute gastroenteritis cases in developing and developed countries. Proper sanitation or disinfection are critical strategies to minimize human norovirus-caused disease until a reliable vaccine is created. Grape seed extract (GSE) is a mixture of plant-derived polyphenols used as a health supplement. Polyphenols are known for antimicrobial, antifungal, and antibiofilm activities, but antiviral effects are not well-known. In studies presented here, plant-derived polyphenols outperformed chemical disinfectants (i.e., free chlorine and peracetic acids) in inactivating Tulane virus, a human norovirus surrogate. Based on data from molecular assays and molecular docking simulations, the current model is that the polyphenols in GSE bind to the Tulane virus capsid, an event that triggers virion aggregation. It is thought that this aggregation prevents Tulane virus from entering host cells.
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- Award ID(s):
- 2023248
- NSF-PAR ID:
- 10355182
- Editor(s):
- Buan, Nicole R.
- Date Published:
- Journal Name:
- Applied and Environmental Microbiology
- Volume:
- 88
- Issue:
- 9
- ISSN:
- 0099-2240
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1128/aem.02247-21
