食品中花生过敏原及其检测方法的研究进展

花生是常见的过敏原之一,能够引起严重的过敏反应。由于缺乏明确的治疗花生过敏的方法,只能让花生过敏患者尽量避免食入含有花生的食物。但在实际的生产过程中,食品加工往往需要经过复杂的生产工艺,会造成食品之间的交叉污染,部分食品难以准确判断是否含有花生过敏原。因此对于食品中花生过敏原的检测方法的开发就显得尤为重要。本文主要对花生中过敏原的种类及其检测方法的研究进展进行了综述,主要对以下几种方法做了介绍,包括酶联免疫吸附法(ELISA)、免疫印迹法、聚合酶链式反应(PCR)等,以及新兴的生物传感器和质谱法,并对检测方法的未来发展趋势进行了展望。     

食物过敏原蛋白检测技术研究进展

目前食物过敏已经成为重要的食品安全问题,该文对食物中过敏原蛋白的检测方法进行综述,为不同食物中蛋白过敏原的检测提供依据。主要介绍了食物蛋白过敏原检测技术的新发展,包括酶联免疫吸附试验、免疫印迹法、免疫层析法、PCR法、SPR技术和质谱技术,并对食物过敏原检测方法的前景作出了展望。     

牛奶过敏原检测方法研究进展

牛奶是八大食物致敏原之一,能引起严重的过敏反应。如何实现食物中牛奶过敏原的快速,准确筛检已成为食品安全领域关注的焦点。牛奶主要过敏原为酪蛋白、α-乳白蛋白、β-乳球蛋白,其检测方法有电泳法、色谱法、酶联免疫实验(ELISA)、传感器、基于质谱的蛋白质组学(LC-MS/MS)、聚合酶链式反应技术(PCR)等。本文就其检测方法的原理和应用进行综述,旨在为食品中牛奶过敏原的检测提供技术方向,以便保障牛奶过敏患者的安全。     

环介导等温扩增技术检测花生过敏原

花生引起的过敏已经越来越受到重视,因此对花生过敏原进行检测也变得越来越重要。目前对花生过敏原的检测大多数采用抗原抗体法或PCR方法,抗原抗体法耗时比较长,而PCR方法需要昂贵的仪器设备。本项目通过建立环介导等温扩增快速检测技术来检测食物中花生过敏原的基因,为食品中花生过敏原成分检测提供方便。该方法快速,简便,灵敏度高,可以很好的应用到现实检测中去,这个方法的建立具有很重大的意义,为食品的安全检测提供了很大的方便。     

花生过敏原及其检测方法研究进展

花生过敏可导致某些人群严重的食品安全问题。过敏患者只能通过避免食用含有花生过敏原成分的食物来避免过敏。但是,食品在生产加工、储存、运输、销售过程中有可能被过敏原污染。因此,确定各类加工食品中是否含有花生过敏原成分,对于预防食用者发生花生过敏反应具有重要意义。花生中已确定的过敏原蛋白有13种(Ara h 1~Ara h 13)。本文综述了花生中过敏原蛋白的结构信息,当前流行的提取方法,以及各种定性定量的检测方法,总结了各种方法的优缺点。同时对建立一种具有特异性强、灵敏度高、定量准确的花生致敏蛋白检测方法的发展趋势进行了展望。     

靶向蛋白质组学质谱技术在食物过敏原定量检测中的应用

食物过敏原的定量检测是实现食物过敏风险评估与风险管理的重要技术保障。现有国家标准中食物过敏原的检测方法主要为聚合酶链式反应(PCR)法和酶联免疫吸附(ELISA)法。针对现有方法存在的不足与缺陷,本文着重介绍了靶向蛋白质组学质谱技术及其在食物过敏原定量检测中的应用,分析该技术的优缺点及应用前景,为食物过敏原定量检测方法的建立提供依据。     

加工导致的花生过敏原蛋白结构变化及其对性质的影响

花生是世界粮农组织(FAO)认证的八大过敏食物之一,花生可导致严重的过敏反应,甚至危及生命。由于花生作为食物配料有广泛的应用,人们对花生过敏越来越关注。本文对加工后花生过敏原蛋白结构变化与性质变化之间的关系研究进行了综述,为探索加工定向改变花生过敏原蛋白的结构和性质提供方向。     

鸡蛋过敏原表位研究进展

鸡蛋过敏是一种常见的食物过敏反应,是人体对鸡蛋中蛋白质成分产生的一种变态反应。食物过敏反应的物质基础是抗原表位与抗体对位,解决食物过敏反应问题的关键一点即需要深入研究出过敏原的表位。本文介绍了鸡蛋中6种主要过敏原,简述了过敏原表位的定位方法,并详细综述了卵白蛋白、卵类粘蛋白、卵转铁蛋白和溶菌酶的过敏原表位研究进展。本文可为进一步鸡蛋过敏研究提供理论指导,也可为表位成分的定量检测以及无毒副作用鸡蛋过敏原疫苗的开发等方面提供一些参考。     

虾类过敏原的识别、纯化和检测技术研究

虾类是人类优质的食用蛋白资源之一,也是联合国粮农组织公布的八大类过敏食物之一。虾类过敏反应严重影响着过敏人群的身体健康和生活质量,为此开展虾类过敏原的识别、纯化和检测技术研究非常必要。通过问卷调查初步了解食物过敏现状,获取自诉虾类过敏患者血清和正常人阴性对照血清,采用特异性IgE检测试剂盒筛选虾类过敏血清。提取南美白对虾蛋白,进行十二烷基硫酸钠-聚丙烯酰胺凝胶电泳及免疫印迹识别虾类过敏蛋白,并对患者识别率最高的虾类的主要过敏原进行分离纯化。采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳、免疫印迹和酶联免疫吸附测定等方法对纯化虾蛋白进行检测分析。患者识别的南美白对虾致敏原的分子质量依次约为200、175、116、85和36kDa,通过硫酸铵盐析及等电点沉淀等方法可以得到电泳纯的虾主要过敏蛋白。免疫印迹结果证实纯化的虾蛋白是具有过敏原性的原肌球蛋白,在此基础上,建立了虾原肌球蛋白的酶联免疫吸附测定方法。     

文蛤特异性过敏原免疫识别的初步研究

目的：贝类是人类最优质的食用蛋白资源之一,也是联合国粮农组织公布的八大类过敏食物之一,贝类过敏反应严重影响着过敏人群的身体健康和生活质量,为此开展贝类过敏原的识别检测研究很有必要。方法：通过问卷调查初步了解食物过敏现状,获取自诉贝类过敏患者血清和正常人阴性对照血清,采用特异性IgE 检测试剂盒筛选贝类过敏血清,应用组织捣碎提取蛋白、聚丙烯酰胺凝胶电泳和免疫印迹等实验方法研究文蛤特异性过敏原。结果：文蛤肌肉主要蛋白的相对分子量约为200kD 以上、200、90、80、70、46、36 和24kD,其中能被贝类过敏血清特异性识别的90kD 组分约占文蛤肌肉总蛋白的10%～20%,且主要为盐溶性蛋白。结论：文蛤的特异性过敏原为90kD 蛋白组分。     

Effect of roasting history and buffer composition on peanut protein extraction efficiency

Peanut is a major allergenic food. Undeclared peanut (allergens) from mis-formulation or contamination during food processing pose a potential risk for sensitized individuals and must be avoided. Reliable detection and quantification methods for food allergens are necessary in order to ensure compliance with food labelling and to improve consumer protection. The extraction of proteins from allergenic foods and complex food products is an important step in any allergen detection method. In this study, the protein extraction efficiency of various buffers prepared in-house and some extraction buffers included in some commercial allergen enzyme-linked immunosorbent assay (ELISA) test kits for peanut determination in food products were tested. In addition, the effect of roasting history on the extractability of peanut protein was investigated by the biuret and the bicinchoninic acid (BCA) assays. Elevated roasting temperatures in food processing were found to have a major impact on protein extraction efficiency by reducing protein yields of oil and dry roasted peanuts by 50-75% and 75-80%, respectively, compared with the raw material. Extraction buffers operating in the higher pH range (pH 8-11) showed best yields.     

IDENTIFICATION AND QUANTIFICATION OF MAJOR PEANUT ALLERGENS (IN CHINA) WITH IGE-BINDING PROPERTY

Peanut allergens have not been studied in China. This study aimed to investigate (1) whether there are differences in the relative amounts of major peanut allergens between the Chinese peanut varieties and the American, and (2) the effect of cooking methods on peanut allergenicity. The allergenic property of raw peanuts and peanut preparations was assessed by immunoblotting and enzyme-linked immunosorbent assay. The relative contents of the major peanut allergens were quantified by sodium dodecyl sulphate-polyacrylamide gel electrophoresis densitometry. For results, Ara h 1 and Ara h 3 were major peanut allergens in China. The amounts of Ara h 1 and Ara h 3 in peanut varieties differ significantly and were both lower than the American varieties. The immunoglobulin E (IgE)-binding ability of different processed peanuts to IgE was not significantly different. Therefore, peanut varieties may induce different amounts of allergens. The relative lower contents of Ara h 1 and Ara h 3 may lead to the lower prevalence of peanut allergy.

PRACTICAL APPLICATIONS

Because of its nutritional and rheological properties, peanut is used in a wide range of different foods, and peanut allergy represents an important health problem. It is essential to identify the compounds of peanut allergens and to study their characteristics in order to explore approaches for the therapies and to breed the nonallergenic peanut seed.     

High-resolution Orbitrap™-based mass spectrometry for rapid detection of peanuts in nuts

Peanut represents one of the most harmful allergenic foods capable of triggering severe and sometimes lethal reactions in allergic consumers upon ingestion of even small amounts. Several proteins capable of inducing allergic reactions that have been recognised by patients’ IgE antibodies have been identified from this nut source. Methods mainly based on ELISA assays have been developed in order to detect peanuts in several food commodities. In addition LC-MS/MS methods based on different mass analysers have also been devised for tracing peanut contamination in different foods achieving low limits of detection. The applicability of a benchtop high-resolution Exactive? mass spectrometer has never been investigated for the rapid screening of peanut contamination in complex food matrices like mixtures of nuts. We report in this paper the design of suitable peanut markers and the development of an high-resolution Orbitrap? mass spectrometer-based method for peanut detection in a mixture of nuts species. With this aim, different types of samples were prepared: (1) nuts-based powder made up of a mixture of hazelnuts, pistachios, almonds and walnuts; and (2) nuts powder fortified with peanuts. Different levels of fortifications were produced and the applicability of the method was tested. Finally, a subset of six peptides fulfilling specific analytical requirements was chosen to check the suitability of the method tailored to the detection of peanuts in nuts-based products, and two of them, peptides VYD and WLG, were selected as quantitative markers. The method proved to be a suitable screening tool to assess the presence of traces of peanuts in other tree nuts with a limit of detection as low as 4 µg of peanuts proteins or 26 µg of peanuts in 1 g of matrix.     

Development of a Biological Assay to Determine the Allergenic Potential of Foods

Food allergies represent a risk for many people in industrialized countries. Unrecognizable allergenic proteins of foodstuffs may be present as ingredients that are not labeled or as unknown cross-contamination. Such hidden allergens can cause severe reactions in allergics, even at minute quantities, sometimes with fatal outcome. For the verification of the presence of allergenic food constituents, analytical methods such as ELISA and PCR have been developed. However, these tests cannot measure allergenic potential. For this reason, a test system that measures the biological activity of allergens has been developed. It is based on the cellular mechanisms of the type I allergy. Rat basophilic leukemia cells (RBL-2H3) were transfected with the genes of the human high affinity receptor for IgE. The resulting cell line expressed the human receptor α-chain and could bind allergenspecific IgE from allergic subjects, in contrast to the parent cell line. After cross-linking of receptor-bound, allergen-specific human IgE by allergens, the cells released measurable inflammatory mediators. These cells were used for the analysis of a variety of allergen extracts, including extracts prepared from foods containing allergenic hazelnut and peanut. The comparative validation with existing ELISA and PCR for hazelnut and peanut demonstrated similar sensitivity and specificity. The established cell line will be a novel tool in the detection of allergens in complex mixtures, especially to address the issue of their allergenic potential, which cannot be accomplished by classical analytical methods. This will add valuable information about the allergenic potential of food constituents to the risk assessment of foods.     

Peanut varieties with reduced Ara h 1 content indicating no reduced allergenicity

Peanut allergy is a major cause of food‐induced severe anaphylactic reactions. To date, no medical care is available to prevent and treat peanut allergy and therefore hypoallergenic peanut varieties are of considerable health political and economic interest. Major allergens that induce IgE‐responses in peanut‐sensitive patients are Ara h 1, Ara h 2 and Ara h 3/4. In order to identify hypoallergenic peanuts, commercially locally available peanut varieties were screened for their allergen content. Ara h 1‐deficient peanuts from Southeast Asia were identified by SDS‐PAGE, immunoblotting, inhibition assays and ELISA. 2‐D PAGE analyses demonstrated the different compositions of the tested extracts and revealed a number of variations of the allergen patterns of peanuts from different varieties. Mediator release experiments of these peanut extracts demonstrated similar allergenicities as compared with standard peanut extract. These results indicate that the allergenicity of peanuts with reduced Ara h 1 content might be compensated by the other allergens, and thus do not necessarily cause a reduction of allergenicity.     

Peanut Allergy,Peanut Allergens,and Methods for the Detection of Peanut Contamination in Food Products

ABSTRACT: Attention to peanut allergy has been rising rapidly for the last 5 y, because it accounts for the majority of severe food‐related anaphylaxis, it tends to appear early in life, and it usually is not resolved. Low milligram amounts of peanut allergens can induce severe allergic reactions in highly sensitized individuals, and no cure is available for peanut allergy. This review presents updated information on peanut allergy, peanut allergens (Ara h1 to h8), and available methods for detecting peanuts in foods. These methods are based on the detection of either peanut proteins or a specific DNA fragment of peanut allergens. A summary of published methods for detecting peanut in foods is given with a comparison of assay formats, target analyte, and assay sensitivity. Moreover, a summary of the current availability of commercial peanut allergen kits is presented with information about assay format, target analyte, sensitivity, testing time, company/kit name, and AOAC validation.     

食品过敏原检测技术研究进展

目前食物过敏在人群中的収生率呈明显上升趋势,食物过敏已成为突出的食品安全问题。食物过敏事敀最有敁的预防方式是过敏者避克食用过敏食物,因此检测不同食物中是否含有过敏原其有十分重要的意义。本文比较了食品法具委员会、澳大利亚、加拿大、中国、欧盟、日本、南非、美国对食品过敏原标识管理的情况,综述了基于蛋白水平的酶联克疫(enzyme-linked immuno sorbent assay, ELISA)法、克疫层析技术和基于核酸水平的实时荧光定量PCR技术、环介导等温扩增技术(loop-mediated isothermal amplification, LAMP)检测食物过敏原的方法,探讨了质谱法以及生物芯片、生物传感器等兵他新关检测技术在过敏原检测领域的应用,有利于加强食品质量监管的力度,确保食品安全。     

原料及热处理对花生致敏性的影响

花生过敏严重影响健康。简述花生中主要过敏原的一般特征,详细介绍了原料及热风干燥、蒸煮、煎炸和焙烤等热处理对花生致敏性的影响,为研究和开发无过敏或低过敏性花生制品提供了一定的科学依据。