Bjelland S, Hjelmeland K, Volden G
Institute of Fisheries, University of Tromsø, Norway.
Arch Dermatol Res. 1989;280(8):469-73. doi: 10.1007/BF00427658.
Cod Gadus morhua and bovine trypsin degraded human epidermal keratin with similar efficacies in vitro around optimal pH, which was at pH 8.4 for cod trypsin and at pH 9.5 for bovine trypsin. Extract of intestines of cod, Atlantic herring Clupea harengus, Atlantic salmon Salmo salar, and redfish Sebastes marinus degraded keratin with similar efficacies with pH optima between 8.5 and 9.5. Sheets of plantar callus were degraded with somewhat lower efficacy than keratin. The keratin-degrading activity of extract of cod intestines had a temperature optimum around 45 degrees C. Inhibition with benzamidine and 4-phenylbutylamine showed that trypsin amounted to more than 2/3 of the keratin-degrading activity in all extracts of fish intestines. Apart from cod intestines, which had the lowest chymotrypsin content, chymotrypsin made a smaller but significant contribution to the keratin-degrading activity. The present investigation demonstrates that fish trypsin and extract of fish intestines are effective in degrading human epidermal keratin in vitro, and in a recent investigation the same was shown with fish pepsin. This may suggest a possible mechanism for the development of irritative contact eczema caused by exposure to fish.
鳕鱼（Gadus morhua）胰蛋白酶和牛胰蛋白酶在体外最适pH值附近降解人表皮角蛋白的效率相似，鳕鱼胰蛋白酶的最适pH值为8.4，牛胰蛋白酶的最适pH值为9.5。鳕鱼、大西洋鲱（Clupea harengus）、大西洋鲑（Salmo salar）和红鱼（Sebastes marinus）的肠提取物降解角蛋白的效率相似，最适pH值在8.5至9.5之间。足底胼胝片的降解效率略低于角蛋白。鳕鱼肠提取物的角蛋白降解活性在约45℃时具有最佳温度。用苯甲脒和4-苯基丁胺抑制表明，在所有鱼肠提取物中，胰蛋白酶占角蛋白降解活性的2/3以上。除了胰凝乳蛋白酶含量最低的鳕鱼肠外，胰凝乳蛋白酶对角蛋白降解活性的贡献较小但很显著。本研究表明，鱼胰蛋白酶和鱼肠提取物在体外能有效降解人表皮角蛋白，并且在最近的一项研究中，鱼胃蛋白酶也有同样的效果。这可能提示了接触鱼引起刺激性接触性湿疹的一种可能机制。
