Cui Tianqi, Fan Ya, Liu Yaping, Fan Xuejing, Sun Yuxue, Cheng Guiguang, Cheng Jianjun
Faculty of Food Science and Engineering, Kunming University of Science and Technology, Kunming 650550, China.
College of Food Science, Northeast Agricultural University, Harbin 150030, China.
Foods. 2023 Dec 23;13(1):67. doi: 10.3390/foods13010067.
This paper investigated the antibacterial mechanism of spermidine-capped carbon dots (S-PCDs) against . The results showed that there were a large number of amino groups on the surface of S-PCDs and they had a high positive charge (+47.06 mV), which could be adsorbed on the negatively charged bacterial surface through electrostatic interaction and changed the permeability of the bacterial cell membrane. The extracellular protein and nucleic acid contents of treated with S-PCDs were 5.4 and 1.2 times higher than those of the control group, respectively. The surface folds and defects of the bacterial cell membrane, and the leakage of cell contents were observed using SEM and TEM. The expression of metabolic oxidation regulatory genes , and was upregulated and the intracellular ROS generation was induced, causing bacterial oxidative stress and eventually bacterial death. S-PCDs can effectively inhibit biofilm formation and had low cytotoxicity. The S-PCD treatment successfully inhibited microbial reproduction when pasteurized milk was stored at 25 °C and 4 °C. These results provide important insights into the antimicrobial mechanism of S-PCDs and lay the foundation for their application in the food field as a potentially novel bacteriostatic nanomaterial.
本文研究了亚精胺封端的碳点（S-PCDs）对……的抗菌机制。结果表明，S-PCDs表面存在大量氨基，且具有较高的正电荷（+47.06 mV），其可通过静电相互作用吸附在带负电荷的细菌表面，改变细菌细胞膜的通透性。经S-PCDs处理的……细胞外蛋白质和核酸含量分别比对照组高5.4倍和1.2倍。利用扫描电子显微镜（SEM）和透射电子显微镜（TEM）观察到细菌细胞膜的表面褶皱和缺陷以及细胞内容物的泄漏。代谢氧化调节基因……的表达上调，并诱导细胞内活性氧（ROS）生成，导致细菌氧化应激并最终导致细菌死亡。S-PCDs可有效抑制生物膜形成，且细胞毒性较低。当巴氏杀菌乳在25℃和4℃储存时，S-PCD处理成功抑制了微生物繁殖。这些结果为S-PCDs的抗菌机制提供了重要见解，并为其作为一种潜在的新型抑菌纳米材料在食品领域的应用奠定了基础。
