海蜇Ⅰ型胶原蛋白的提取及结构特性研究

以海蜇为原料，采用盐酸-胃蛋白酶法提取胶原蛋白，并通过聚丙烯酰胺凝胶电泳（SDS-Polyacrylamide gel electrophoresis，SDS-PAGE）、紫外光谱（UV-visible spectroscopy，UV）、氨基酸分析、红外光谱（Fourier-transform infrared spectroscopy，FTIR）、圆二色谱（Circular dichroism，CD）以及扫描电镜（Scanning electron microscope，SEM）对其结构特性进行了系统全面的研究。结果显示，海蜇胶原蛋白在135 kDa左右有一条α-链，在245 kDa以上有一条β-链和γ-链，紫外吸收峰在233 nm处，符合I型胶原蛋白的特征，其亚基组成可能为α₁(I)]₃。海蜇胶原蛋白中含量最高的氨基酸为甘氨酸，占氨基酸总量的25.99%，且含有15.94%的亚氨基酸。红外光谱和圆二色谱均表明海蜇胶原蛋白分子排布紧凑，具有主要由氢键构成的完整三螺旋结构。扫描电镜结果显示海蜇胶原蛋白具有多层聚集、以纤维为主的无规则网状结构。

Extraction and Structural Characteristics of Type Ⅰ Collagen from Rhopilema esculenta

In this study,collagen was extracted from Rhopilema esculenta using hydrochloric acid-pepsin methodology,and its detailed structure were characterized by SDS-Polyacrylamide gel electrophoresis(SDS-PAGE),UV-visible spectroscopy(UV),amino acid analysis,Fourier-transform infrared spectroscopy(FTIR),circular dichroism(CD),and scanning electron microscope(SEM).The SDS-PAGE pattern of Rhopilema esculenta collagen presented anα-chain at about 135 kDa with aβ-chain andγ-chain above 245 kDa.In addition,the UV absorption peak of Rhopilema esculenta collagen was centered at 233 nm,revealing that the Rhopilema esculenta collagen herein adopted the feathers of type I collagen with a possible subunit composition ofα1(I)]3.The most abundant amino acid in Rhopilema esculenta collagen was glycine,accounting for 25.99%of the total amino acids.Besides,the collagen in this work contained 15.94%imino acid.Results of Fourier transform infrared spectroscopy and circular dichroism suggested that the Rhopilema esculenta collagen presented a compact triple helix structure that maintained primarily by hydrogen bonds.The images of Rhopilema esculenta collagen under SEM observation showed mainly irregular networks consist mainly of multilayered fibers.