鱼皮胶原蛋白的纯化及酶解性质的研究

Study on Purification of Fish Skin Collagens and Characters of Their Enzymatic Degradation

分别对鲨鱼、鲢鱼、草鱼、罗非鱼鱼皮的胶原蛋白进行提取、纯化并进行SDS PAGE电泳分析,对它们的酶解性质进行研究.结果表明,提取的胶原蛋白有较高纯度,是典型的I型胶原蛋白.4种鱼皮胶原蛋白均能被胰蛋白酶和蛋白酶K水解,两种酶酶切位点有差异.不同鱼种鱼皮胶原蛋白的一级结构不同.本实验的酶解条件是适宜的.

Fish skins are potential sources of collagen.Therefore SDS-PAGE analyses and studies on characters of enzymatic degradation were conducted on collagens extracted and purified from shark,silver carp,grass carp and tilapia by using a salt precipitation method.The extraction and purification were carried out by a series of steps involving removing non-collagenous proteins with 0.1 mol/L sodium hydroxide,removing fat with 10% iso-propanol,extracting collagen with 0.5 mol/L acetic acid and salting out with sodium chloride.As a results,four kinds of collagens extracted were high purified.They were all showed to comprised at least three peptide chains and be similar to each other.It suggested that they belonged to typical collagen I.In addition,four collagens could be all degraded by trypsin and proteinase K,and the methods of enzymatic degradation adopted were effective.The enzyme activity of proteinase K was stronger than that of trypsin.As showed by SDS-PAGE analysis,the bands were different when the same fish skin collagen was degraded by two proteinases respectively.It suggested that split sites of two proteinase were different.On the other hand,it also appeared different bands among different fish skin collagens degraded by the same proteinase,indicating that primary structure of skin collagen differs among species.