PROBLEM TO BE SOLVED: To provide a pharmaceutical product having antiviral activity against new and seasonal human influenza viruses, with a polysaccharide fraction extracted from microalgae coccomyxa as an active ingredient.SOLUTION: Such a polysaccharide fraction that a majority of lipids are removed from microalgae coccomyxa is provided. A method for producing an antiviral agent with the polysaccharide fraction as an active ingredient, is also provided, being characterized by including: a step of conducting ultrasonic shaking and centrifugally separating with microalgae coccomyxa and a volatile solvent combined together a step of conducting a delipidizing twice or more with a volatile solvent a step of adding a necessary amount of water thereafter followed by heating for a necessary period of time to conduct a hot-water extraction and a step of condensing and evaporating to dryness a liquid layer obtained by conducting a solid-liquid separation of the resultant hot-water extract by centrifugal separation. By this method, a majority of lipids can be removed from microalgae coccomyxa thanks to the repeated lipids-removing step, enabling a high-purity extract to be obtained. Because of having high antiviral activity against new and seasonal A-type human influenza viruses, this antiviral agent can be used as a pharmaceutical product.COPYRIGHT: (C)2013,JPO&INPIT【課題】微細藻類のコッコミクサより抽出された多糖体画分を有効成分とする新型及び季節性のヒトインフルエンザウイルスに対して、抗ウイルス医薬品の提供。【解決手段】微細藻類のコッコミクサより大半の脂質が除去された多糖体画分であり、微細藻類のコッコミクサと揮発性溶剤とを一緒にして超音波振とう及び遠心分離を行なう工程と、揮発性溶剤で脱脂操作を複数回行なう工程と、脱脂工程後に所要量の水を加え所要時間に亘って加熱し熱湯抽出する工程と、熱湯抽出物を遠心分離により固液分離した液層を濃縮し乾燥する工程とからなることを特徴とする抗ウイルス剤の製法であり、繰り返しの脂質除去工程を行うことによって大半の脂質が除去できるのであり、純度の高い抽出物を得ることができ、新型及び季節性のA型ヒトインフルエンザウイルスに対する高い抗ウイルス活性を有するので医薬品として使用できる。【選択図】なし
