Antivirus effects of polysaccharides from Sargassum fusiforme in vitro

AIM: To assay antiviral effects of the polysaccharide and separated products from Sargassum fusiforme on herpes simplex virus type 1 (HSV-1) and coxsackie virus (CVB₃) and their antiviral mechanism. METHODS: The antiviral effects of all extracts from Sargassum fusiforme on HSV-1 and CVB₃ and their cytotoxicity on Vero cells were studied by CPE and MTT methods. Antiviral mechanism of two extracts was also investigated by four different ways. RESULTS and CONCLUSION: ① The cytotoxicity of extracts on Vero cells was undetectable (CC₅₀＞5 000 mg/L). ② All extracts except algin (ALG) had an obviously HSV-1 inhibitory effect. Antiviral activities of them were increasingly strengthened with their purities. Antiviral activities of extracts from flucoidan 1, F₁, F₂ and F₄ were better than acyclovir (ACV). ③ Antiviral activities of all extracts on CVB₃ were better than ribavirin injection. F₁, F₂ and F₄ had remarkable anti-CVB₃ effects. ④ The experiment showed that Sargassum fusiforme polysaccharides not only kill the above viruses directly but also restrain them via getting into cells or absorbing on cells.