title: N₂ gas plasma inactivates influenza virus mediated by oxidative stress.
abstract: Here we show that N₂ gas plasma, produced by applying a short high-voltage pulse using a static induction (SI) thyristor power supply inactivates influenza virus. N₂ gas plasma treatment of influenza A and B viruses induced the degradation of viral proteins, including nucleoprotein, hemagglutinin, and neuraminidase. The injury of viral RNA genome and the inactivation of hemagglutination were also observed after N₂ gas plasma treatment. These changes were possibly due to changes in the viral envelope, because modification of the lipid content was also suggested by Fourier-transformed infrared spectroscopy. At least three major mechanisms of action (heat, UV-A, and oxidative stress (i.e. hydrogen peroxide-like molecules)) were found in this system. Among them, oxidative stress appeared to be the main factor in the inactivation of influenza virus. In addition, there was an increase in the nitrotyrosine content of viral proteins, suggesting that oxidative stress produced by N₂ gas plasma generation oxidized proteins. As a result, oxidation may be the most important factor in the inactivation, degradation, and modification of influenza virus by N₂ gas plasma.
authors.affiliation: Laboratory of Biometabolic Chemistry, School of Health Sciences, Faculty of Medicine, University of the Ryukyus, 207 Uehara, Nishihara, Okinawa 903-0215, Japan.
authors.forename: Akikazu
authors.initials: A
authors.lastname: Sakudo
authors.affiliation: Department of Electrical and Electronic Engineering, Faculty of Science and Engineering, Saga University, Saga 840-8502, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Misawa
authors.affiliation: NGK Insulators Ltd., Mizuho-ku, Nagoya 467-8530, Japan.
authors.forename: Naohiro
authors.initials: N
authors.lastname: Shimizu
authors.affiliation: Laboratory of Biometabolic Chemistry, School of Health Sciences, University of the Ryukyus, Nishihara, Okinawa 903-0215, Japan.
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Imanishi
mesh_terms: D015153:Blotting, Western; D002846:Chromatography, Affinity; D004202:Disinfectants / Q000737:chemistry / Q000494:pharmacology*; D004797:Enzyme-Linked Immunosorbent Assay; D006386:Hemagglutination Tests; D008855:Microscopy, Electron, Scanning; D009584:Nitrogen / Q000737:chemistry* / Q000494:pharmacology*; D009975:Orthomyxoviridae / Q000187:drug effects* / Q000648:ultrastructure; D018384:Oxidative Stress / Q000187:drug effects*; D059748:Proteolysis / Q000187:drug effects; D060888:Real-Time Polymerase Chain Reaction; D013053:Spectrophotometry; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D014759:Viral Envelope Proteins / Q000378:metabolism*
chemical_list: D004202:Disinfectants; D014759:Viral Envelope Proteins; D009584:Nitrogen