几种提取方法制备的糙刺参体壁胶原蛋白的特性分析

Characteristics of collagens from body wall of Stichopus horrens prepared by different extraction methods

为考察不同提取方法对糙刺参体壁胶原蛋白分子结构和理化性质的影响,该研究以糙刺参体壁为研究对象,分别提取酸溶性胶原蛋白(acid-soluble collagen,ASC)、酶溶性胶原蛋白(pepsin-solubilized collagen,PSC)、超声波辅助酸溶性胶原蛋白(ultrasound-assisted extraction of acid-soluble collagen,UASC)和超声波辅助酶溶性胶原蛋白(ultrasound-assisted extraction of pepsin-solubilized collagen,UPSC),比较分析不同提取方法的提取率、SDS-PAGE、紫外光谱、红外光谱、热稳定性及圆二色光谱数据。结果显示,UPSC提取率最高,为18.70%,ASC提取率仅为0.15%,未用于后续研究;SDS-PAGE结果表明,PSC、UPSC、UASC的亚基组成均为(α1)2α2;红外光谱显示,3种胶原蛋白均存在酰胺A、B、Ⅰ、Ⅱ和Ⅲ带,均保持了胶原蛋白三螺旋结构的完整性,经超声波处理后,α螺旋含量降低,β折叠和β转角含量增加;PSC、UPSC、UASC的热变性温度分别为21.3、25.9、27.0℃;圆二色光谱和紫外光谱表明,3种胶原蛋白均符合Ⅰ型胶原蛋白的典型结构特征。综上,可初步判断糙刺参体壁胶原蛋白为Ⅰ型胶原蛋白,超声波辅助提取未破坏胶原蛋白的三螺旋结构,且能促进胶原蛋白的提取。研究结果可为糙刺参体壁胶原蛋白的后续开发利用提供依据。

To investigate the effects of different extraction methods on the molecular structure and physicochemical properties of collagens from the body wall of Stichopus horrens,acid-soluble collagen(ASC),pepsin-solubilized collagen(PSC),ultrasound-assisted extraction of acid-soluble collagen(UASC),and ultrasound-assisted extraction of pepsin-solubilized collagen(UPSC)were extracted from the body wall of S.horrens,the extraction rate,SDS-PAGE,ultraviolet spectrum(UV),Fourier transform infrared spectrum(FTIR),thermal stability and circular dichroism spectrum(CD)of different extraction methods were compared and analyzed.Results showed that the extraction rate of UPSC was the highest(18.70%)and that of ASC was only 0.15%,which was not used in subsequent studies.SDS-PAGE showed that the subunit composition of PSC,UPSC,and UASC was(α1)2α2.FTIR spectrum showed that there were amide A,B,Ⅰ,Ⅱ,andⅢbands in all three kinds of collagens,which maintained the integrity of the triple helix structure of collagens,after ultrasonic treatment,the contents ofα-helix decreased,while the contents ofβ-pleated sheet andβ-turn increased.The thermal denaturation temperatures of PSC,UPSC,and UASC were 21.3℃,25.9℃,and 27.0℃,respectively.CD and UV spectrum showed that three kinds of collagens were consistent with the typical structural characteristics of typeⅠcollagen.In conclusion,it could preliminarily be judged that the collagens from the body wall of S.horrens were typeⅠcollagen,ultrasonic-assisted extraction did not destroy the triple helix structure of collagens,it could promote the extraction of collagens.This study could provide basic data for the further development and utilization of collagens from the body wall of S.horrens.