納豆是日本傳統食品，在日本使用超過 1000 年。納豆所含納豆激酶，是一種具有分解纖維蛋白的絲胺酸蛋白酶，具有溶解血栓的功能。近來成為廣泛應用於預防血栓引起的心血管疾病之保健食品。納豆激酶其活性與人體的纖維蛋白溶解酶相似，其溶解血栓活性比體內纖維蛋白溶解酶還強。目前生物科技的發達，納豆激酶可被分離出來添加於各式各樣保健食品中。本研究的主要目的，乃是針對市場上琳瑯滿的納豆產品，測量其納豆激酶含量，並找出納豆激酶的最適當分析方法。本研究選用人體的血清樣本，使納豆激酶 對於纖維蛋白具有更強的專一性，降解更多的纖維蛋白分解產物，以利吸光值的提高，是本實驗優點。使用納豆激酶協會的分析方法測定納豆產品中納豆激酶的活性，再進一步用纖維蛋白平板法驗證納豆產品的納豆激酶活性。在本研究中發現，所測量的納豆激酶活性，大多低於產品所標示的含量。16 種納豆產品中只有 2 件符合其產品標示，以台灣的 I 品牌的納豆產品，納豆激酶活性最高。納豆激酶的溶栓能力，以纖維蛋白平板法驗證的結果顯示，台灣的 I 品牌溶栓所產生的透明圈最大，代表其納豆激酶的活性最高。每種產品所產生的透明圈 是代表對交聯蛋白的溶解。用人體內源性的溶栓物質纖維蛋白溶解酶當標準品，相當於在人體產生溶解
血栓效果。本實驗結果可對市售納豆產品參差不齊的納豆激酶活性，一目了然。服用血栓溶解劑 Warfarin 的患者，可供醫師對納豆產品與藥物的交互作用有參考的依據。 Netto is traditional Japanese food which has been used for over 1000 years. A strong fibrinolytic enzyme (Nattokinase) in the Natto. Netto has a property called Nattokinase which has fibrinolytic enzyme which can decomposing fibrin. In recent years it has been used as a health product to prevent heart disease and stroke. Nattokinase activity is similar to plasmin in the human body. The dissolution of clots is even stronger than Plasmin. Using Nattokinse in different kind of health products is getting popular due to advanced biotechnology. This research is centred round the natural fibrinolytic activity in Nattokinase. Japan Bio Science Laboratory Co., Ltd analyised the activity in Nattokinase and used the fibrin plate method to prove the activity. There are 16 Natto products in the market, only 2 have reached government guideline standard and we have found that the product in Product I has the highest volume of Nattokinase activity on the market. In our new analysis by using the fibrin plate method we have confirmed that Product I has higher levels of Nattokinase which benefits preventing blood clots. Every product has different levels of Nattokinase which can cause different plasmin in your body which can either harm or increase good health. High content of Nettokinase per unit makes more expensive for the product. For Warfrain users, they must be advised by their doctor as any level of Nettokinase in the product may cause health concern.
