Hata Yuuki, Bouda Yuta, Hiruma Sumiyo, Miyazaki Hiromi, Nakamura Shingo
Division of Biomedical Engineering, National Defense Medical College Research Institute, 3-2 Namiki, Tokorozawa-shi 359-8513, Japan.
Nanomaterials (Basel). 2022 Oct 20;12(20):3681. doi: 10.3390/nano12203681.
Microbial cells and self-produced extracellular polymeric substances assembled to form biofilms that are difficult to remove from surfaces, causing problems in various fields. Seashell-derived calcium hydroxide, a sustainable inorganic material, has shown high bactericidal activity even for biofilms due to its alkalinity. However, its biofilm removal efficacy is relatively low. Herein, we report a biofilm degradation strategy that includes two environmentally friendly reagents: seashell-derived calcium hydroxide and hydrogen peroxide. A biofilm model of was prepared in vitro, treated with calcium hydroxide-hydrogen peroxide solutions, and semi-quantified by the crystal violet stain method. The treatment significantly improved biofilm removal efficacy compared with treatments by calcium hydroxide alone and hydrogen peroxide alone. The mechanism was elucidated from calcium hydroxide-hydrogen peroxide solutions, which suggested that perhydroxyl anion and hydroxyl radical generated from hydrogen peroxide, as well as the alkalinity of calcium hydroxide, enhanced biofilm degradation. This study showed that concurrent use of other reagents, such as hydrogen peroxide, is a promising strategy for improving the biofilm degradation activity of seashell-derived calcium hydroxide and will contribute to developing efficient biofilm removal methods.
微生物细胞与自身产生的胞外聚合物组装形成生物膜，这些生物膜很难从表面去除，在各个领域都引发了问题。贝壳衍生的氢氧化钙是一种可持续的无机材料，由于其碱性，即使对生物膜也显示出高杀菌活性。然而，其生物膜去除效果相对较低。在此，我们报告了一种生物膜降解策略，该策略包括两种环境友好型试剂：贝壳衍生的氢氧化钙和过氧化氢。在体外制备了生物膜模型，用氢氧化钙 - 过氧化氢溶液处理，并通过结晶紫染色法进行半定量分析。与单独使用氢氧化钙和单独使用过氧化氢的处理相比，该处理显著提高了生物膜去除效果。从氢氧化钙 - 过氧化氢溶液中阐明了其机制，这表明过氧化氢产生的过羟基阴离子和羟基自由基，以及氢氧化钙的碱性增强了生物膜降解。这项研究表明，同时使用其他试剂，如过氧化氢，是提高贝壳衍生氢氧化钙生物膜降解活性的一种有前景的策略，并将有助于开发高效的生物膜去除方法。
