中国科技网 > 国际频道 > 独家编译
分享到:

食物中的风险

来源:中国科学网 作者:张微编译 2016年09月07日 11:14
[导读] Fraunhofer研究所的研究人员正在建立新技术,在食物生产过程中除去过敏物质,或对它们进行处理保证它们不再引起过敏。

食物中的风险

多年来,食物过敏一直呈现增长态势。对于患者来说,目前只有一个解决方案:避免食用引发过敏的食品。Fraunhofer研究所研究人员对保护消费者做出了重要贡献,他们开发了具体、可靠的方法,检测食用中的过敏物质。此外,他们正在建立减少食物成分中引发过敏特性的工艺。他们的研究工作侧重于大豆。

对每个人来说,吃饭不都是愉快的经历。餐后,许多人出现腹痛、瘙痒或腹泻。这些症状往往是由食物过敏引起的。特别是花生,鱼,牛奶,含有麸质的谷物,鸡蛋,芹菜,甲壳纲动物(如螃蟹、龙虾),可食用的坚果,芥末、芝麻和大豆蛋白,这些食物都能触发不良反应。那些受影响的人没有其他选择,只能避免食用 “他们的”过敏原。但这并不是一件容易的事,可能会有微量的过敏原在无意中进入你的食物,例如,当不同的产品在一台机器上加工时。由于这些遗迹不是一种食物成分,因此它们并不总是列在包装上。食品中隐藏的过敏原会给过敏的人带来健康风险。

LowAllergen项目中,Fraunhofer研究所正在努力改善对食物过敏的人的境况。Fraunhofer的四个研究所,细胞治疗和免疫学IZI,工艺学和包装IVV,分析生物学和应用生态学IME以及毒理学和实验医学ITEM,正在合作开发食物过敏分析、过敏原的可靠评估,减少食物中潜在的过敏物质,以及确定过敏原的检测方法。他们的目的是找出过敏蛋白,并建立新技术在食物生产过程中除去过敏物质,或对它们进行处理保证它们不再引起过敏。为了实现这一目标,研究人员正在与莱比锡大学医院进行合作。

货架上几乎没有非过敏食品

“到目前为止,除了婴儿食品,没有低敏和不含过敏原的食品。这类产品的生产非常复杂。原因之一是,虽然食品配料中的过敏性成分能够被检测出来,但是直到现在,还是不能确定其具体的致敏性,” IZI经理Michael Szardenings博士说。以大豆为例,研究人员和团队现在已经成功地做了这一点。“人体对各种外来物质都会产生抗体。根据我们的研究,就大豆而言,非常容易引发过敏”。现在,科学家开发了一种新方法,可用于识别蛋白质的过敏性成分/区域,这些蛋白质通过患者抗体被识别出来,专家称它们为抗原决定簇,存在于血清中的抗体”内。过敏的人体内被激活的抗体是由于特定过敏原的分子。患者对这些分子发生反应,被称为抗原决定簇。我们能够识别374种与过敏有关的抗原决定簇,项目经理说。为此,研究人员分析了50种大豆过敏患者的血清。在这个过程中,他们在研究所使用了噬菌体识别技术,这种方法用于研究蛋白质和区分抗体的相互作用。

大豆蛋白引起过敏的几率不高

位于弗赖辛的Fraunhofer IVV研究人员表明,大豆蛋白可以被修改,使它们不会引发过敏。现在利用很多技术都可以进行大豆蛋白分离的生产和修改。应用不同的加热方法,如等离子体处理,脉冲紫外线,γ辐射、高压以及化学,酶和发酵工艺都可以做到。科学家们能够提取具有极低免疫反应的大豆蛋白成分,特别是通过酶水解和微生物发酵技术的结合。“酶水解法的目的是减少抗原决定簇,蛋白质中的过敏成分。特殊的抗原决定簇,构象决定簇,也能够通过展开和折叠蛋白质结构被消除掉,或者是蛋白质的氨基酸序列被破坏,” Fraunhofer IVV科学家,项目协调员Peter Eisner博士说。用这种方法生产的大豆蛋白也具有良好的感官体验,包括更好的味道。“我们已经申请了低过敏性蛋白质生产的专利,” Eisner说。

新的过敏测试——一滴血就够了

通过FoodAllergen项目,科学家们希望他们的研究结果和已经建立的方法能够应用到其它食物中。为了提高诊断水平,IVV, IZI  IME的研究人员们正计划与莱比锡大学医学开展合作,进行过敏患者血清检查的大规模研究。一个目标是建立生物银行,包含超过500个过敏患者的血清样本。“我们正致力于开发一项测试,让食物过敏患者仅用一滴血就可以进行检查,” Szardenings说。例如,如果一个人对花粉过敏,那么他或她的血清往往对大豆蛋白发生反应。这意味着刺破试验的发现将具有积极意义,虽然患者所关心的并不是是否对大豆过敏。“用我们的测试方法,一个人能够精确地知道自己是否存在大豆过敏的风险。它可以立即在医学实践中进行评估,” Szardenings.说。研究人员的另一个想法是将评估与应用程序结合起来。一个人用智能手机对测试结果拍照,稍后,他就会通过应用程序收到结果,这个应用程序与评估软件连接。FoodAllergen项目是2016年春天发起的,持续到2019年3月。Fraunhofer未来基金会对该项目进行资助,金额是660万欧元。

“英文原文”

Risks in your food

Food allergies have been on the increase for years. There is currently only one solution for patients: avoid allergy-triggering products. Fraunhofer researchers are making an important contribution to consumer protection by developing methods to specifically and reliably detect allergenic substances in foods. In addition, they are helping to establish processes that reduce the allergy-triggering properties of food ingredients. Their research work focuses on soy.

Eating is not a pleasurable experience for everyone. After a meal, many people suffer from abdominal pain, itchiness or diarrhea. These complaints are often caused by a food allergy. Particularly peanuts, fish, milk, cereals containing gluten, eggs, celery, crustaceans, edible nuts, mustard, sesame seeds and soy proteins trigger the undesired reactions. Those affected have no other choice but to avoid food with "their" allergen. However, this is no easy task – even the smallest quantities of allergens can get into food unintentionally, for instance when different products are processed in one machine. Since these traces are not an ingredient, they are not always listed on the packaging. The hidden allergens in foods pose a health risk for people with food allergies.

In the LowAllergen project, several Fraunhofer institutes are joining forces to improve the situation of those with food allergies. The four institutes – The Fraunhofer Institute for Cell Therapy and Immunology IZI, for Process Engineering and Packaging IVV, for Molecular Biology and Applied Ecology IME and for Toxicology and Experimental Medicine ITEM – are working together on the development of innovative food allergy analyses, the reliable evaluation of allergens, the reduction of the allergenic potential of foodstuffs and detection methods that exactly determine this. The aim is to identify allergenic proteins and establish technologies to remove these during food production or treat them so that they no longer cause allergies. They are cooperating with Leipzig University Hospital for this purpose.

Hardly any non-allergenic foodstuffs on the shelves

"To date there are no food products, except for baby food, that are hypoallergenic and contain few allergens. The production of such products is very complex. One reason for this is that although the allergenic components of food ingredients can generally be detected, to date, it is not possible to determine their specific allergenicity," says Dr. Michael Szardenings, group manager at IZI. Yet, taking soy as an example, the researcher and his team have now succeeded in doing exactly this. "The human body can develop antibodies against all kinds of foreign substances. According to our findings, in the case of soy, this occurs in more places in the allergenic proteins than expected." Now the scientists have established a method that can be used to identify the allergenic components/regions of proteins recognized by the patient's antibodies – experts call these epitopes – directly in the antibodies in the blood serum. "Antibodies activated in a person with an allergy are directed against specific molecular sections of the allergens. Patients react to these molecular sections, known as epitopes. We were able to identify 374 allergy-relevant epitopes," said the subproject manager. To this end, the researchers analyzed 50 blood sera of patients with a soy allergy. During the process, they used a peptide phage display refined at the institute, a method which, among other things, is used for studying proteins and for clarifying antibody interactions.

Soy proteins that trigger fewer allergies

In addition, colleagues at Fraunhofer IVV in Freising showed that soy proteins can be modified so that they are less allergenic. Soy protein isolates were produced and modified using a wide variety of methods. Various heating methods were applied, such as treatment with plasma, pulsed UV light, gamma radiation and high pressure as well as chemical, enzymatic and fermentative processes. Scientists were able to extract soy protein ingredients with especially low immune reactivity, particularly via the combination of enzymatic hydrolysis and a microbial fermentation. "Enzymatic hydrolysis aims to reduce the epitopes, the allergenic components of the proteins. Special epitopes, known as conformational epitopes, can also be eliminated through the folding and unfolding of the protein structure or the amino acid sequence of the proteins is destroyed," explains Dr. Peter Eisner, a scientist at Fraunhofer IVV and project coordinator. The soy proteins produced in this manner also have improved sensory properties, including better taste. "We have already filed a patent application for the production of hypoallergenic protein preparations," says Eisner.

New allergy test – a drop of blood suffices

Through the FoodAllergen project, the scientists want to build on their research results and apply established methods to other food allergies. To continue improving patient diagnostics, Fraunhofer researchers at IVV, IZI and IME are planning to examine the sera of allergy sufferers on a large scale in cooperation with Leipzig University Hospital. One aim is a biobank with more than 500 sera of those affected. "We are working on a test that will enable a broad range of food allergies to be detected with just one drop of the patient's blood," according to Szardenings. For example, if someone is allergic to birch pollen, his or her antibodies often react to soy proteins. This means the prick test finding would be positive although the person concerned is not actually allergic to soy. "With our test, one can precisely determine whether there is a risk of a soy allergy. It could even be evaluated immediately at the medical practice," says Szardenings. Another idea from the researchers is to combine the evaluation with an app in the future. "A person takes a photo of the test with his smartphone. He receives the result shortly after via the app, which is connected with the evaluation software." The FoodAllergen project was launched in the spring of 2016 and runs until March 2019. The Fraunhofer Future Foundation is sponsoring the project with a sum of EUR 6.6 million.

点击下载:

更多精彩!欢迎扫描下方二维码关注中国科技网官方微信(zgkjwwx)

关注中国科技网官方微信
[责任编辑:吴可]
分享到:

相关阅读:

网友评论表达个人看法,并不表明本网同意其观点或证实其描述。

验证码:

验证码
京ICP备06005116号     互联网新闻信息服务许可     网络视听许可证0113654号     京公网安备 110402500060
中国科技网 版权所有