Novel antiviral activity of dialdehyde starch

A significant effort worldwide is being directed toward development of novel biocides against drug-resistant bacterial and viruses because of the significant potential human infection risks in the general population. We report here the discovery of a strong antiviral biocide, dialdheyde starch (DAS). Antiviral tests were carried out against three non-envelop viruses, including two bacterial viruses MS2 and PRD1, and one human virus Poliovirus. Dialdehyde starch aqueous suspensions were effective biocides against these three test viruses in a 1 hr exposure test. The antiviral activity was significantly enhanced in a four-hour exposure test, with maximum seven orders of magnitude reductions against MS2 and PRD1, and four-order reduction against Poliovirus. The antiviral activity of dialdehyde starch was found to be pH dependent, being more active in alkaline and acidic conditions than in neutral conditions.

Conditions for SARS-CoV cultivation and inactivation / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To study the method for cultivation and inactivation of SARS-CoV.</p><p><b>METHODS</b>In order to choose the sensitive cell strain and the best infection dose of the virus, Vero, Vero-E6 and 2BS cell lines were infected with SARS-CoV. The cultivation temperature was selected among 25 degrees C, 33 degrees C and 37 degrees C. The best inactivating time and effect were observed with beta-propiolactone whose concentration ranged from 1:2000 to 1:20,000 at room temperature.</p><p><b>RESULTS</b>Vero and Vero-E6 cell lines were sensitive to SARS-CoV. The cytopathic changes of the cells were 75% at 37 degrees C in 5 percent CO2 incubator after infection. SARS-CoV was inactivated completely in beta-propiolactone (1:4000). The toxicity of beta-propiolactone was hydrolyzed completely when the inactivated virus was cultured for 16 hours at 2 degrees C, 8 degrees C and in water bath for 2 hours at 37 degrees C.</p><p><b>CONCLUSION</b>The titer of SARS-CoV was the highest when it was cultured in Vero or Vero-E6 cells for 72 hours at 37 degrees C in 5 percent CO2 incubator. SARS-CoV was inactivated completely in beta-propiolactone when its concentration was 1:4000 and the interaction time was 1 hour.</p>