Objective: We examined anti-influenza virus (anti-IFV) activity of Coix-seed Reactive Derivatives (CRD) extract.Methods: H1N1 A/Puerto Rico/8/34 (PR8) strain was infected to Malin Darby Canine Kidney (MDCK) cells. The infected cells were cultured by medium supplemented CRD extract for 24 h, and the supernatants were harvested to analyze virus titer by focus-forming reduction assay. Polyphenols were removed by PVPP treatment, and anti-influenza virus activity was compared with normal CRD extract. Results: CRD extract showed anti-IFV activity. In addition, CRD extract inhibited viral adsorption and replication. The study of CRD extract by PVPP treatment suggested that polyphenols are the main active component. Conclusion: This study revealed that CRD extract has anti-IFV activity against PR8 strain. The mechanism of action was inhibited viral adsorption and replication. It was also suggested that anti-IFV activity of CRD extract is due to polyphenols.

Objective: A study was conducted to clarify the anti-influenza virus effect of agricultural, forest and fishery products in Ishikawa Prefecture. Method: The samples were prepared by both hot-water and ethanol extraction. The Madin-Darby canine kidney (MDCK) cells infected with PR8 strain were cultured in Dulbecco's Modified Eagle Medium（DMEM） containing extract for 24 hours and measured virus titer of supernatants by focus-forming reduction assay. Time-of-addition assay was performed to determine the inhibition stage in virus proliferation by the extract. The active ingredients were purified using a solid-phase extraction column (silica gel base C18). Results: We revealed that many products have anti-influenza virus activity. Especially, four products ( Matteuccia struthiopteris, Colocasia esculenta, Sagittaria trifolia, and Eleucine coracana) show strong activity and inhibit several stages in virus proliferation. Conclusion: We performed screening to 46 agricultural, forest and fishery products and found the four products ( Matteuccia struthiopteris, Colocasia esculenta, Sagittaria trifolia, and Eleusine coracana) inhibit virus proliferation strongly. In addition, the isolation and identification of the active ingredients contained in these remain as a future study.