Article ID: 2025-033
Current measures to prevent viral infections use disinfectants that are highly irritating to the skin and cause health problems such as alcohol-induced hypersensitivity. Therefore, a demand for safer disinfectants exists. ε-Poly-L-lysine (polylysine, EPL) has been used as a food preservative for many years because of its safety and antibacterial properties. In recent years, we developed an antiviral agent consisting only of food additives containing EPL. Studies on feline calicivirus, a norovirus substitute, have shown that serine proteases decompose the protein structure of the outer shell of this virus. The combination of serine proteases and EPL further enhanced the virucidal effects of serine proteases like subtilisin. Investigations of the antiviral effects of this combination revealed its inhibitory effects on enveloped viruses, such as the influenza A virus, but not on non-enveloped viruses. To confirm the damage to viruses, whose infectivity was inhibited by the combined treatment with serine proteases and EPL, morphological changes in virus particles after treatment were observed using transmission electron microscopy. Following the treatment with serine proteases or EPL, the outer shells of the examined viruses were damaged. As the outer shell contributes to the infection of host cells, this morphological alteration might be responsible for the reduced infectivity of these viruses after the combination treatment with serine proteases and EPL.
