ABSTRACT

Owing to its nontoxicity and better efficiency, low-temperature plasma (LTP) has been proposed to be a strong antibacterial agent against multidrug-resistant bactericidal pathogens. On the other hand, previously several food-borne pathogens were treated by chemically hazardous and least-efficient irradiation techniques. Because of its superior efficiency, in the current study, we implemented LTP protective mechanism against Escherichia coli (E.coli). In particular, we investigated the sterilization effects of plasma on the degradation of pure samples of E.coli strain (${10}^7$ colony forming units) in the presence and absence of ${\mathrm{H}}_2{\mathrm{O}}_2$ fumes. Interestingly, the proposed mechanism improved considerably the microbial reduction, inactivation efficiency and kill rate of the plasma-treated E.coli samples. The decrease in bactericidal cell viability was confirmed by deoxyribonucleic acid (DNA) quantification and membrane damage by protein leakage test. The reactive oxidants species (ROS) were explored via optical emission spectroscopy (OES). For the investigation of the surface characteristics, we carried out the scanning electron microscopy (SEM) analysis of the plasma-treated nutrient media containing E.coli colonies. The reported results confirmed that low pressure and low temperature plasma can be a potential alternative for the degradation of multidrug-resistant E. coli.

摘要

由于其无毒和更好的效率，低温等离子体 (LTP) 被认为是一种针对多重耐药杀菌病原体的强抗菌剂。另一方面，以前有几种食源性病原体通过化学危险和效率最低的辐照技术进行处理。由于其优越的效率，在目前的研究中，我们实施了针对大肠杆菌（E.coli）的LTP 保护机制。特别是，我们研究了等离子体对大肠杆菌菌株纯样品降解的灭菌效果（${10}^7$ 菌落形成单位）存在和不存在 ${\mathrm{H}}_2{\mathrm{哦}}_2$烟雾。有趣的是，所提出的机制大大提高了等离子体处理的大肠杆菌样品的微生物减少、灭活效率和杀灭率。杀菌细胞活力的降低通过脱氧核糖核酸 (DNA) 定量和蛋白质渗漏试验的膜损伤得到证实。通过光发射光谱（OES）探索活性氧化剂（ROS）。为了研究表面特征，我们对经等离子体处理的含有大肠杆菌菌落的营养培养基进行了扫描电子显微镜 (SEM) 分析。报告的结果证实，低压和低温等离子体可以成为降解多重耐药大肠杆菌的潜在替代方案。