当归对乌鳢肌原纤维蛋白微观结构的影响及作用机制

Effects of angelica on microstructure of snakehead myofibrillar protein and its mechanism

以乌鳢(Ophiocephalus argus)肌原纤维蛋白为研究对象,考察当归(Angelica sinensis)粉或当归浸提液对乌鳢肌原纤维蛋白微观结构的影响,并探讨其作用机制。扫描电镜及SDS-PAGE结果表明,加入1%~2%的当归时,乌鳢肌原纤维蛋白的微观结构变得更加致密,有利于形成更为致密的三维网络结构,提高鱼糜制品的品质;但大量(3%~5%)当归的添加会使原本致密的蛋白网络结构变得松散。傅里叶红外光谱和圆二色谱实验表明,随着当归粉或者当归浸提液含量的增加,乌鳢肌原纤维蛋白中二级结构α-螺旋和β-转角的总相对含量会先增加后减少,而β-转角和无规卷曲总的相对含量会先降低再升高。

Myofibrillar protein is the key protein affecting the quality of surimi products.Scanning electron microscopy and SDS-PAGE was used to investigate the effects of angelica powers and its extracts on the microstructure of snakehead myofibrillar protein and its mechanism.The results showed that myofibrillar protein structure was more compact.Adding a small quantity of angelica powder facilitated the formation of 3D network structure.The quality of surimi products was improved to some extent.However,the myofibrillar protein structure was loose when the massive angelica was added into the surimi,indicating that the protein network structure was destroyed.The total relative content ofα-helix andβ-turn contain in myofibrillar protein increased first and then decreased,while the total relative content ofβ-turn and random coil determined by both fourier transform infrared spectroscopy and circular dichroism decreased first and then increased.It will provide a theoretical basis for the exploration of new upmarket surimi products with nutrition and health care function.