κ-卡拉胶对马氏珠母贝肌肉水溶性蛋白稳定性的影响

Effect of Kappa-carrageenan on the Stability of Water Soluble Proteins Extracted from Pinctada martensii Muscle

【目的】探究Kappa-卡拉胶对马氏珠母贝肌肉水溶性蛋白稳定性的影响,为进一步开发利用马氏珠母贝肉以及改善水产肌肉蛋白加工特性提供数据参考。【方法】以马氏珠母贝肌肉水溶性蛋白(WSP)为研究对象,采用浊度法、聚丙烯酰胺凝胶电泳(SDS-PAGE)分析不同pH值条件下,热处理前后kappa-卡拉胶对WSP稳定性的影响,同时利用凝胶过滤层析对WSP进行了初步的分离及分子质量分布分析。【结果】热处理前后,在酸性条件下(pH<4.0)添加了kappa-卡拉胶的胶体蛋白混合体系(K-WSP)透光率均下降;热处理前,pH4.0～5.0范围内,与WSP对照,K-WSP混合体系透光率上升,而pH> 5.0条件下,kappa-卡拉胶对WSP体系透光率无显著性影响;热处理后,pH 4.0～7.5范围内,与WSP对照,K-WSP混合体系透光率上升,而pH>8.0条件下,kappa-卡拉胶对WSP体系透光率无显著性影响。SDS-PAGE结果显示:热处理前,酸性pH条件下与未添加WSP相比较,K-WSP在35 ku附近条带较多。热处理后,WSP和K-WSP的大分子蛋白组分(200、116 ku)均基本发生了热变性。WSP分离纯化曲线显示出两个组分,分子质量分别分布于200～35 ku和35～14.4 ku。【结论】pH值4.0～5.0条件下,kappa-卡拉胶对WSP的热稳定性有一定促进作用。

【Objective】To explore the effect of Kappa-carrageenan on the stability of water-soluble proteins extracted from Pinctada martensii meat(WSP)and provide data reference for the use of P.martensii meat and improving the processing properties of aquatic muscle protein【.Methods】The effects of kappa-carrageenan on WSP stability before and after heat treatment were analyzed under different pH conditions by turbidity and SDS-PAGE analysis.Furthermore,the separation and molecular weight distribution of WSP were analyzed by gel filtration chromatography.【Results】The results showed that light transmittance of the WSP system with kappa-carrageenan(K-WSP)decreased under acidic conditions(pH<4.0)before or after heat treatment.After heat treatment,in the range of pH 4.0– 7.5,the light transmittance of K-WSP system increased comparing with WSP.At pH >8.0,kappa-carrageenan had no significant effect on the light transmittance of WSP.Before heat treatment,the light transmittance of K-WSP system increased in the range of pH 4.0–5.0.At pH >5.0,kappa-carrageenan had no significant effect on the light transmittance of WSP.SDS-PAGE results showed that,before heat treatment,K-WSP had more bands near 35 ku under acidic pH conditions when it was compared with WSP.After heat treatment,the macromolecular protein component(200 ku,116 ku)of K-WSP and WSP were substantially thermally denatured.The separation and purification curve of WSP showed the appearance of two components with molecular weights ranging from 200– 35 ku and 35– 14.4 ku,respectively.【Conclusion】Kappa-carrageenan has a promoting effect on the thermal stability of WSP under pH 4.0– 5.0.