[Antiviral activity of sulfated polysaccharide from the brown algae Laminaria japonica against avian influenza A (H5N1) virus infection in the cultured cells].

The antiviral activity of the sulfated polysaccharide fucoidan from the brown sea algae Laminaria japonica against infection caused by highly virulent avian influenza virus (Alduck/Novosibirsk/02/05, H5N1) in the sensitive pig embryo kidney cell cultures was studied. Fucoidan was ascertained to have no cytotoxic activity and to show virucidal activity against influenza A/H5N1 virus. When given at concentrations of 50 to 500 microg/ml, fucoidan protected the cell cultures from the cytopathogenic activity of influenza virus in a dose of 0.01 TCID50/1.0 ml and was able to suppress influenza A/H5N1 virus production within 24 hours of infection when prophylactic and therapeutic-and-prophylactic treatment regimens were used.