School of Chemical and Biomolecular Engineering, The University of Sydney, Darlington, NSW, 2006, Australia.
School of Chemistry and Physics, Queensland University of Technology, Brisbane, QLD, 4000, Australia.
NPJ Biofilms Microbiomes. 2021 Jan 27;7(1):11. doi: 10.1038/s41522-020-00180-6.
Biofilms have several characteristics that ensure their survival in a range of adverse environmental conditions, including high cell numbers, close cell proximity to allow easy genetic exchange (e.g., for resistance genes), cell communication and protection through the production of an exopolysaccharide matrix. Together, these characteristics make it difficult to kill undesirable biofilms, despite the many studies aimed at improving the removal of biofilms. An elimination method that is safe, easy to deliver in physically complex environments and not prone to microbial resistance is highly desired. Cold atmospheric plasma, a lightning-like state generated from air or other gases with a high voltage can be used to make plasma-activated water (PAW) that contains many active species and radicals that have antimicrobial activity. Recent studies have shown the potential for PAW to be used for biofilm elimination without causing the bacteria to develop significant resistance. However, the precise mode of action is still the subject of debate. This review discusses the formation of PAW generated species and their impacts on biofilms. A focus is placed on the diffusion of reactive species into biofilms, the formation of gradients and the resulting interaction with the biofilm matrix and specific biofilm components. Such an understanding will provide significant benefits for tackling the ubiquitous problem of biofilm contamination in food, water and medical areas.
生物膜具有多种特性，使其能够在各种不利的环境条件下生存，包括高细胞数量、紧密的细胞接近度，从而便于基因交换（例如，抗性基因）、细胞通讯以及通过产生胞外多糖基质进行保护。这些特性共同使去除不需要的生物膜变得困难，尽管有许多研究旨在改善生物膜的去除。人们非常希望有一种安全、易于在物理复杂环境中传递且不易产生微生物耐药性的消除方法。冷等离子体是一种在高电压下从空气或其他气体中产生的类似闪电的状态，可以用来制造含有多种具有抗菌活性的活性物质和自由基的等离子体激活水 (PAW)。最近的研究表明，PAW 有可能用于消除生物膜，而不会导致细菌产生明显的耐药性。然而，其确切的作用模式仍存在争议。本文讨论了 PAW 生成物种的形成及其对生物膜的影响。重点关注反应性物质向生物膜中的扩散、梯度的形成以及与生物膜基质和特定生物膜成分的相互作用。这种理解将为解决食品、水和医疗领域中普遍存在的生物膜污染问题提供重要的益处。
