蛋白酶的相对分子质量对其在制革过程传质的影响  

Effect of Molecular Weight of Protease on its Mass Transfer in Leather Processing

作　　者：宋映 马远 曾运航[1] 石碧[1,2] 

机构地区：[1]四川大学制革清洁技术国家工程实验室,四川成都610065 [2]四川大学皮革化学与工程教育部重点实验室,四川成都610065

出　　处：《皮革科学与工程》2018年第1期5-10,24,共7页Leather Science and Engineering

基　　金：国家自然科学基金(21406145);四川省青年科技创新研究团队资助项目(2017TD0010)

摘　　要：用荧光双标记技术研究了浸水、酶法脱毛、软化和鞣后酸性软化过程中蛋白酶的相对分子质量对其在皮/革内传质的影响。结果表明,浸水和脱毛过程中,由于牛皮厚度大、粒面附有表皮和毛、皮胶原纤维未分散,蛋白酶不能渗透整层牛皮,并且酶的相对分子质量对其在皮内的传质影响很小。软化过程中,由于表皮和毛去除彻底、胶原纤维分散良好,蛋白酶较易渗入裸皮,且相对分子质量较小的蛋白酶的渗透速率明显更快,故选用相对分子质量较小的蛋白酶对均匀软化具有重要意义。鞣后酸性软化过程中,尽管削匀蓝湿革薄且胶原纤维分散好,蛋白酶却不能完全渗透蓝湿革,酶的相对分子质量也基本不会影响蛋白酶在革内的传质。这可能是因为酸性蛋白酶的用量少、在浴液(pH 3.5,铬含量27 mg/L)中溶解不完全,且易与蓝湿革表层的铬结合。The effects of molecular weight of proteases on their mass transfer in soaking, unhairing, bating and wet blue bating processes were investigated by using fluorescent double labeling technique. It was found that protease could not fully penetrate the whole cattle hide and that the molecular weight of protease had little effect on its mass transfer in the hide during soaking and unhairing processes. It can be explained that the cattle hide was thick and had intact epidermis,hair and a poor dispersion of collagen fibers in these two processes. In bating process, protease could penetrate the pelt more easily owing to a complete removal of epidermis and hair, as well as a good dispersion of collagen fibers. Meanwhile,it was obvious that the protease with lower molecular weight had a faster mass transfer rate in the pelt. This phenomenon suggests that it is important to choose a protease with lower molecular weight for achieving a uniform bating performance.Moreover, in wet blue bating process, although the shaved wet blue leather was thin and had a good dispersion of collagen fibers, protease could not penetrate the whole leather, and the molecular weight of protease could scarcely affect its mass transfer in the leather. This should be due to the fact that a small number of acid protease could not be fully dissolved in the bath（ pH 3.5, chrome concentration 27 mg/L） and might even bind with chrome in the surface layer of the wet blue leather.

关 键 词：制革 蛋白酶 传质 相对分子质量 荧光双标记技术 

分 类 号：TS543[轻工技术与工程—皮革化学与工程]