本文以俄罗斯鲟鱼皮为原料，采用酸法和酶法提取胶原蛋白，研究了酸溶性胶原蛋白（ASC）和酶促溶性胶原蛋白（PSC）的蛋白类型、结构、热变性温度和溶解度等理化性质，并与牛跟腱I型胶原蛋白（BATC）进行比较。SDS-PAGE电泳图显示ASC和PSC均包含了两条α链（α1链和α2链），为I型胶原蛋白；傅立叶红外光谱图表明提取的2种胶原蛋白均保存了完整的三螺旋结构，但ASC的有序度相对较高；ASC和PSC的热变性温度分别为32.48 ℃和32.68 ℃，低于BATC；在酸性pH条件下（pH 1~4），ASC和PSC溶解度较高，当NaCl浓度大于2%时，PSC的溶解度较高；扫描电镜显示2种胶原蛋白均为网状结构，ASC的孔径较均匀，且孔径较小。上述结果表明提取方法不同，导致2种胶原蛋白的理化性质具有一定的差异，但都具有较好的热稳定性、溶解性，能形成较好的网状结构，有潜力的作为胶原蛋白的替代来源。

The skin of Acipenser gueldenstaedtii was used as the raw material in this study, and collagens were extracted using acid and pepsin extraction methods. The protein type, structure, thermal denaturation temperature, solubility, and other physicochemical properties of acid soluble collagen (ASC) and pepsin soluble collagen (PSC) were studied and compared with those of bovine achilles tendon type I collagen (BATC). SDS-PAGE patterns revealed that both ASC and PSC contained two typical α chains (α1 chain and α2 chain) and were type I collagens. The Fourier transform infrared spectroscopy (FT-IR) results indicated that both extracted collagens had a triple helical structure, but ASC had a higher degree of molecular order. The denaturation temperatures of ASC and PSC were 32.48 ℃ and 32.68 ℃, respectively, which were lower than that of BATC. Both ASC and PSC had a relatively high solubility at acidic pH (pH 1~4). PSC had a higher solubility when the NaCl concentration was higher than 2%. Scanning electron microscopy (SEM) showed that the two collagen sponges had a network structure, and the pore size of ASC was relatively uniform and small. These results indicate that different extraction methods may lead to certain differences in the physicochemical properties of ASC and PSC; however, both collagens have good thermal stability and solubility, as well as the ability to form a better network structure than BATC. Therefore, the skin from Acipenser gueldenstaedtii can serve as an alternative source of collagens.

浙江省中青年学科带头人学术攀登项目（pd2013100）；宁波市农业重大择优委托攻关项目（2012C10024）；企业横向项目（HK2013000105）