食品过敏原原肌球蛋白高静压处理后活性及结构变化规律研究

Food allergy has become a major health concern of WHO and FAO, which leads to international trade disputes and causes significant economic losses. Crustaceans are one of the most common causes of food allergies and tropomyosin (TM) is the most important allergen protein. .In order to reduce the allergenicity and ensure consumption safety, many researches were focus on the effects of different treatments such as enzymolysis, ultra-high pressure, boiling and microwave and so on, on molecular and antigenicity of allergy protein. Among them Ultra-high pressure (UHP) was considered as an effective pre-treatment method for shrimp processing (shelling) and had potential role on decrease the allergenicty of shrimp tropomyosin. It was reported that molecular weight of tropomysin did not change after ultra-high pressure but could accelerate the digestion of TM and correspondingly to decrease the antigenicity of protein. However, few research was related in view of change of protein structure and dynamic response of antigen-antibody reaction of protein. .In this study, the major allergen (tropomyosin) in shrimp was chosen as an object the effects of Ultro-high pressure treatment on the activity and structure of food allergenic protein tropomyosin was systematically studied, took new surface plasmon resonance (SPR) sensor as one of the tools to real-time observe the antigen and antibody binding and dissociation reaction, and applied in quantitative analysis of the interaction strength and dynamics, that intends to provide basic data and the theoretical basis for further evaluation of the application of HHP technology in food desensitization and guide significance for the reasonable application of HHP in production, and also provide strong technical support for import and export food allergens monitoring and smooth implementation of related laws and regulations.

食物过敏已成为全世界关注的公共卫生热点问题。甲壳类动物是引起食物过敏的主要致敏原之一，其过敏原主要为存在于肌纤维中的原肌球蛋白。为降低过敏原危害，很多学者采用高温、酶解、超高压等加工方式降低其致敏性。超高压技术被认为是未来甲壳类加工首选技术，并具有降低食物致敏潜力。有研究表明，虾过敏原经不同压力处理后，致敏性出现先降后升的波动。但迄今，针对超高压处理后过敏原活性、蛋白结构变化及抗体与抗原动力学反应等均缺乏深入研究。.本项目以虾过敏原原肌球蛋白为研究对象，采用新型表面等离子共振传感器等技术，首次深入开展高静压下原肌球蛋白结构变化、抗原抗体反应动力学研究，分析原肌球蛋白致敏活性及蛋白结构解聚、交联或裂解等变化，旨在阐明高静压处理后食品过敏原活性及结构变化规律，以期为不同加工方式对食品致敏性影响提供理论基础，同时为食品标签标识、进出口食品过敏原监测、预警以及相关法律法规顺利实施提供有力技术支撑。

食物过敏已成为全球关注的公共卫生热点问题。甲壳类动物是引起食物过敏的主要致敏原之一，其过敏原主要为原肌球蛋白。为降低过敏原危害，很多学者采用高温、酶解、超高压等加工方式降低其致敏性。超高压技术被认为是未来甲壳类加工首选技术，并具有降低食物致敏潜力。研究表明，虾过敏原经不同压力处理后，致敏性出现先降后升的波动。但迄今，针对超高压处理后过敏原活性、蛋白结构变化及抗体与抗原动力学反应等均缺乏深入研究。.项目建立了虾原肌球蛋白纯化方法，预测了其亲水特性，二级结构以及空间结构组成,分析了压力、保压时间、施压温度对蛋白结构、致敏性的影响。研究结果表明：原肌球蛋白经高静压处理后其蛋白结构的改变主要是由于α-螺旋结构的改变而引起的，且使致敏性呈现波动变化。致敏性降低主要是由于少量β-折叠、β-转角及无规则卷曲结构转化为α-螺旋，表面疏水性降低，分子转向折叠状态，导致部分线性表位可能被包埋，反之，则引起蛋白致敏性升高；高静压和温度结合处理对原肌球蛋白致敏性和结构影响更大，其致敏性的降低主要是由于部分蛋白发生氨基酸链的降解，α-螺旋转化为β-折叠、β-转角以及无规则卷曲，部分线性表位和空间构象表位被破坏。研究还表明：高静压使蛋白致敏性降低主要由蛋白两端与中间部位序列构象改变引起。通过分析静电吸附条件、抗体浓度等对抗原抗体互作的影响，建立了SPR技术检测虾肉过敏原原肌球蛋白的方法，分析了虾肉原肌球蛋白与抗体互作的反应动力学。此外，建立了可同时检测乳品中a-乳白蛋白、β-乳球蛋以及as1-酪蛋的LC-MRM/MS方法，灵敏度可达ppm级别，为过敏原原肌球蛋白的精准检测提供参考。.综上所述，项目全面分析了高静压下原肌球蛋白致敏活性及蛋白结构解聚、交联、裂解等变化，阐明了高静压处理后食品过敏原活性及结构变化规律，为不同加工方式对食品致敏性影响提供了理论基础。项目成果发表论文3篇，其中SCI论文1 篇（影响影子3.388）；申请国家发明专利2 项；培养博士研究生1名，完成了预期目标。