Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China.
Dalian Product Quality Inspection and Testing Institute Co., Ltd., Dalian, 116024, China.
Environ Res. 2021 Mar;194:110630. doi: 10.1016/j.envres.2020.110630. Epub 2020 Dec 17.
Selenium nanoparticles (SeNPs) have attracted great interest as a potential antimicrobial agent. However, there is limited research on the antibacterial activity and possible mechanisms of biosynthesized SeNPs. In this study, spherical bio-SeNPs with an average size of 120 nm were synthesized by strain Providencia sp. DCX. The SeNPs were further applied to investigate the antibacterial properties of model bacteria, including Gram-positive (Staphylococcus aureus, Bacillus cereus and Bacillus subtilis) and Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli and Vibrio parahemolyticus). The biosynthesized SeNPs demonstrated strong inhibition activity against the growth of these pathogens. When treated with 500 mg/L SeNPs, most of the tested bacteria were destructed within 12 h, among which the mortality rates of Gram-negative bacteria were much better. The leakage tests illustrated that there existed more proteins and polysaccharides outside the cells after reacted with bio-SeNPs. It was indicated that the leakages of proteins and polysaccharides were caused by permeability changes of membranes and the disruption of cell walls. And the change of reactive oxygen species (ROS) intensity indicated that oxidative damage may play the significant role in the antibacterial processes. The results showed that several bacteria could be effectively inhibited and destructed, suggesting the potential of using the biosynthesized SeNPs as antibacterial agents for bacterial infectious diseases.
硒纳米粒子（SeNPs）作为一种潜在的抗菌剂引起了极大的关注。然而，关于生物合成的 SeNPs 的抗菌活性和可能的机制的研究还很有限。在这项研究中，通过 Providencia sp. DCX 菌株合成了平均粒径为 120nm 的球形生物-SeNPs。进一步应用这些 SeNPs 来研究模型细菌的抗菌特性，包括革兰氏阳性菌（金黄色葡萄球菌、蜡状芽孢杆菌和枯草芽孢杆菌）和革兰氏阴性菌（铜绿假单胞菌、大肠杆菌和副溶血弧菌）。生物合成的 SeNPs 对这些病原体的生长表现出强烈的抑制活性。当用 500mg/L 的 SeNPs 处理时，大多数测试细菌在 12 小时内被破坏，其中革兰氏阴性菌的死亡率要好得多。泄漏试验表明，与生物-SeNPs 反应后细胞外存在更多的蛋白质和多糖。这表明细胞膜通透性的变化和细胞壁的破坏导致了蛋白质和多糖的泄漏。活性氧（ROS）强度的变化表明氧化损伤可能在抗菌过程中起重要作用。结果表明，几种细菌可以被有效抑制和破坏，这表明使用生物合成的 SeNPs 作为抗细菌感染性疾病的抗菌剂具有潜力。
