Isolation and Characterization of Biological Active Materials from Fish Skin Waste

在海洋食品工业中，鱼皮被当作骨头和内脏等废物丢弃，这些废物占整个体重的一半以上，希望用于其他一些产品。鱼皮由约10%的鱼粪组成，可以机械去除，在食品加工中很容易回收。大比目鱼的皮肤含有34%的蛋白质和相关物质，14%的油和52%的水，是日本鸟取县的主要海洋食品加工产品。这种鱼皮的利用有望为当地工业的发展做出贡献。顺便说一句，最近有报道称，肝炎、肝硬变和肝癌等肝病在中年劳动一代的日本人中有迅速增加的趋势。它也成为治疗或改善药物治疗亟待开发的重要课题。本课题首先以鱼皮为原料，建立了胶原蛋白和细胞外基质成分的提取纯化工艺。作为鱼胶原蛋白的应用，我们成功地进行了原代肝细胞的三维培养，结果表明，在此培养条件下，肝功能得到了很好的维持。此外，我们还发现从鱼皮中提取的蛋白多糖粗提物对培养细胞中的HGF具有显著的诱导作用。其中，鱼皮中糖胺多糖的主要成分硫酸皮肤素对HGF的诱导活性最强。由于牛胶原蛋白的使用受限于引起疯牛病和克雅氏病的普恩病毒的感染，因此应重新评估鱼胶原蛋白的重要性。

In the marine food industry, fish skin is discarded as waste like bone and entrails, and these waste materials make-up more than a half of the whole body weight, desired for utilization in some other products. The skin of fish, which is composed of about 10% of fish waste, can be mechanically removed and readily recovered in food processing. The skin of a halibut Reinhararditus hippoglossoides, which is a main marine-food processing product in Tottori Prefecture Japan, contains 34% protein and related materials, 14% oil, and 52% water. The utilization of this fish skin is expected to contribute the development of local industry. Incidentally, liver diseases, such as hepatitis, liver cirrhosis and hepatoma were reported to show a tendency of rapid increase recently within Japanese people in the working generation of middle ages. It has also become an important subject to be urgently developed for therapeutic or ameliorative medication. At first in this project, the extraction and puriflcation process of collagen and extracellular matrix components were established using fish skin. As the application of fish collagen, we have succeeded the three dimensional culture of primary hepatocytes, and revealed that liver function was well maintained in this culture. Furthermore, we showed that proteoglycan crude extracts from the fish skin has significant inducibility of HGF in culture cell. Especially, of the separated glycosaminoglycans, dermatan sulfate which was the main component of glycosaminoglycans in the fish skin, showed the strongest activity in HGF induction. As the use of cattle collagen is restricted for the infection of the prion that is the cause of BSE and the Creutzfeldt-Jakob disease, the importance of fish collagen should be re-evaluated.