牦牛皮胶原蛋白的提取及其性能分析

Extraction and Characterization of Collagen from the Skin of Yak

摘要:

4.以牦牛皮为原料，提取了酸溶性胶原蛋白（ASC）和酶溶性胶原蛋白（PSC），并对胶原蛋白分子的结构和性能进行了分析。结果表明：ASC和PSC的提取率分别为（54±0.18）%和（78±0.42）%；通过紫外吸收光谱（UV）分析、红外吸收光谱分析（FTIR）及电泳分析（SDS-PAGE），表明ASC和PSC具有完整的三股螺旋结构，符合Ⅰ型胶原蛋白的结构特征；氨基酸分析发现ASC和PSC含有丰富的亚氨酸，其含量分别为264.1残基/1000残基和276.6残基/1000残基；热稳定性分析表明ASC和PSC热变性温度为41.5 ℃、47.5 ℃，热收缩温度为62.5 ℃、70 ℃，证明PSC的热稳定性高于ASC；用扫描电子显微镜（SEM）观察ASC和PSC形貌，显示其表面为松散，不规则的纤维网形态；自组装实验说明两者具有一定的成纤维能力，自组装产物的D-周期分别为（68.2±5）nm、（69.3±3）nm，且PSC比ASC的组装速度快。

Abstract:

Yak skin was utilized to prepare the acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC), whose structure and property had been analyzed. The results showed that the extraction rates of ASC and PSC were (54±0.18)% and (78±0.42)%, respectively. The results of ultraviolet absorption spectrum analysis, infrared absorption spectrum analysis and electrophoresis analysis showed that both ASC and PSC had a complete three strand helical structure, which conformed to the structural characteristics of I type collagen. Amino acid analysis indicated that ASC and PSC were rich in imidates at 264.1 residues/1000 residues and 276.6 residues/1000 residues. The thermal stability of ASC and PSC was 41.5 ℃, 47.5 ℃, and the heat shrinkage temperature was 62.5 ℃, 70 ℃. The thermal stability of PSC was higher than that of ASC. ASC and PSC were observed by scanning electron microscopy (SEM) to determin the loose and irregular morphology. Self-assembly experiment illustrated that both ASC and PSC performed the fiber forming ability. Self-assembly experiments showed that PSC and ASC have certain fiber-forming ability, and the D-periodicity of self-assembled products was (68.2±5) nm nm and (69.3±3) nm, respectively, and PSC was assembly faster than ASC.