PROBLEM TO BE SOLVED: To develop antithrombotic agents specifically inhibiting formation or growth of pathologic thrombus without the side effect such as bleeding.SOLUTION: The present invention relates to antithrombotic agents containing sacran that is an Aphanothece Sacram-derived sulfation polysaccharide, and to food and drinks containing the sacran extracted from Aphanothece Sacrum, the food and drinks having antithrombotic effect that inhibits intrinsic blood clotting reactions and does not inhibit extrinsic clotting reactions, as well as to food additives containing sacran.SELECTED DRAWING: NoneCOPYRIGHT: (C)2016,JPO&INPIT【課題】出血の副作用がなく、病的血栓の形成や増大を特異的に阻害する抗血栓剤を開発する。【解決手段】スイゼンジノリ(Aphanothece Sacram)由来硫酸化多糖であるサクランを含む抗血栓剤、およびスイゼンジノリから抽出されたサクランを含有する、内因系血液凝固反応を阻害し、外因系血液凝固反応を阻害しない抗血栓効果を有する飲食物、ならびにサクランを含む食品添加剤。【選択図】なし