When food goes bad: understanding biofilm formation to prevent food spoilage

当食物变质时：了解生物膜的形成以防止食物变质

• 批准号: BB/X010384/1
• 负责人: Laura Nolan
• 金额: $ 51.8万
• 依托单位: Quadram Institute
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=BB%2FX010384%2F1
• 关键词: When; food; goes; bad; understanding

Almost 10% of the world's population do not get enough to eat. Since the global population is predicted to rise to 9.8 billion by 2050, we need to increase levels of food availability by at least 50% to be able to feed the world's population. One proposed solution has been to reduce food loss and wastage (FLW), since it is estimated that around 1/3 of the total food produced for human consumption worldwide is either lost or wasted. A major contributor to FLW is spoilage by microbes. Given these drastic numbers, many governments and global organisations are adopting a multi-pronged approach to ensure we can feed the world over the coming decades. Indeed, the importance of understanding biological processes that lead to food spoilage falls within the BBSRC's Strategic Challenge '3.2.1 Bioscience for Sustainable Agriculture and Food' and the Responsive Mode Priority of 'Reducing Waste in the Food Chain'.Microbes (bacteria, viruses and fungi) grow on the surfaces of food, or on surfaces in the food chain, in a slimy film called a biofilm. Biofilms are found everywhere, from the slimy deposits that form on the bathroom sink, shower and fridge, to the slime seen in ponds or on rocks in nature. The slimy coating acts as a protective layer, making it very difficult to kill microbes when they are in biofilms and to physically remove the biofilm once it has formed. A major group of bacteria that cause spoilage of a range of meat, dairy and vegetable products are broadly called Pseudomonas species. When food in your fridge goes off and you throw it out, it is very likely to be due to these bacteria growing in biofilms on spoiled salad leaves, meat or on the aggregates in spoiled milk. On average 280 kg of food is lost or wasted per adult in the UK, which contributes to approx. 6.7 million tonnes, or 152,000 full lorries, of food wasted each year in the UK alone. There are currently no strategies that directly target biofilm formation on food surfaces to either extend the shelf life of food or stop food spoilage. Overall, the work in this Fellowship aims to: 1. Determine if we can stop Pseudomonas species forming biofilms on food by targeting a common component of the slimy part of biofilms, extracellular DNA (eDNA). Many bacteria have eDNA in the biofilm slime, which provides strength and structure to the biofilm and helps the biofilm resist attempts to remove it. My preliminary data shows that there is eDNA in Pseudomonas species biofilms. I have access to an enzyme called NucB, which can break down eDNA. In this work I will test if putting NucB on food surfaces stops bacteria forming biofilms and if I can remove a biofilm that is already formed on food with NucB. 2. Understand how Pseudomonas species grow in biofilms on food to bring about food spoilage. By understanding this process in detail, we will then be able to develop new ways to stop biofilms forming on food, or on surfaces in the food chain (e.g. in food processing plants or on food packaging) to extend the shelf-life and reduce food spoilage. This work could be directly translated into solutions to reduce the growth of bacteria on food and thus food spoilage. Additionally, the techniques developed in this Fellowship will be very useful in understanding how other bacteria, for instance those that cause food poisoning, are transmitted through the food chain.

世界上近 10% 的人口没有足够的食物。由于预计到 2050 年全球人口将增加到 98 亿，因此我们需要将粮食供应水平提高至少 50%，才能养活世界人口。一项提议的解决方案是减少粮食损失和浪费 (FLW)，因为据估计，全世界为人类消费生产的粮食总量中约有 1/3 被损失或浪费。造成 FLW 的一个主要因素是微生物的腐败。鉴于这些巨大的数字，许多政府和全球组织正在采取多管齐下的方法，以确保我们能够在未来几十年内养活世界。事实上，了解导致食品腐败的生物过程的重要性属于 BBSRC 的战略挑战“3.2.1 可持续农业和食品的生物科学”和“减少食物链中的浪费”的响应模式优先事项。微生物（细菌、病毒）和真菌）在食物表面或食物链表面上生长，形成称为生物膜的粘稠薄膜。生物膜无处不在，从浴室水槽、淋浴间和冰箱上形成的粘液沉积物，到自然界池塘或岩石上的粘液。粘稠的涂层充当保护层，使得当微生物处于生物膜中时很难杀死它们，并且一旦生物膜形成就很难物理去除它们。引起一系列肉类、乳制品和蔬菜产品腐败的主要细菌群被广泛地称为假单胞菌属。当冰箱里的食物变质并被你扔掉时，很可能是由于这些细菌在变质的沙拉叶、肉类或变质的牛奶中的聚集物上的生物膜中生长所致。在英国，每个成年人平均损失或浪费 280 公斤食物，其中约仅在英国，每年就有 670 万吨（即 152,000 辆满载卡车）的食物被浪费。目前还没有直接针对食品表面生物膜形成来延长食品保质期或阻止食品腐败的策略。总体而言，该奖学金的工作目标是： 1. 确定我们是否可以通过针对生物膜粘稠部分的常见成分——细胞外 DNA (eDNA) 来阻止假单胞菌在食物上形成生物膜。许多细菌在生物膜粘液中含有 eDNA，它为生物膜提供强度和结构，并帮助生物膜抵抗去除它的尝试。我的初步数据显示假单胞菌属生物膜中存在 eDNA。我可以获得一种名为 NucB 的酶，它可以分解 eDNA。在这项工作中，我将测试将 NucB 放在食品表面是否可以阻止细菌形成生物膜，以及是否可以用 NucB 去除食品上已经形成的生物膜。 2. 了解假单胞菌如何在食品上的生物膜中生长，从而导致食品腐败。通过详细了解这一过程，我们将能够开发新的方法来阻止食品或食物链表面（例如食品加工厂或食品包装上）形成生物膜，从而延长保质期并减少食品污染。损坏。这项工作可以直接转化为减少食品上细菌生长和食品腐败的解决方案。此外，该奖学金开发的技术对于了解其他细菌（例如引起食物中毒的细菌）如何通过食物链传播非常有用。