School of Environmental Science & Engineering, Xiamen University of Technology, Xiamen 361024, China.
College of the Environment & Ecology, Xiamen University, Xiamen 361102, China.
J Environ Sci (China). 2022 Jul;117:80-90. doi: 10.1016/j.jes.2022.01.038. Epub 2022 Jan 31.
Water-borne pathogenic bacteria are always the top priority to be removed through disinfection process in water treatment due to their threat to human health. It was necessary to develop novel disinfection methods since the conventional chlorine disinfection was inefficient in inactivating chlorine-resistant bacteria, inducing the viable but non-culturable (VBNC) bacteria and forming disinfection by-products (DBPs). In this study, the inactivation of four model strains including Gram-negative (G), Gram-positive (G) and environmental samples by atmospheric-pressure air-liquid discharge plasma (ALDP) was assessed systematically. The results showed that ALDP was superior in inactivating all of the samples compared with chlorination. During 10 min ALDP treatment, the G bacteria were completely inactivated, and the G one was inactivated by more than 4.61 logs. The inactivation of bacteria from a campus lake and a wastewater treatment plant effluent exceeded 99.82% and 97.78%, respectively. For G bacteria, ALDP resulted in a much lower (10∼10 times) levels of VBNC cells than chlorination. ALDP could effectively remove the chlorine-resistant bacteria. More than 96.41% of the intracellular DNA and 99.99% of the extracellular DNA were removed, whereas it was only 56.35% and 12.82% for chlorination. ALDP had a stronger ability to destroy cell structure than chlorination, presumably due to the existence of ROS (·OH, O and O). GC-MS analysis showed that ALDP produced less DBPs than chlorination. These findings provided new insights for the application of discharge plasma in water disinfection, which could be complemental or alternative to the conventional disinfection methods.
水中的致病细菌由于对人类健康的威胁，一直是水处理消毒过程中首要去除的对象。由于传统的氯消毒在灭活抗氯细菌、诱导存活但非可培养（VBNC）细菌和形成消毒副产物（DBPs）方面效率低下，因此有必要开发新的消毒方法。在这项研究中，系统评估了大气压气液放电等离子体（ALDP）对包括革兰氏阴性（G）、革兰氏阳性（G）和环境样本在内的四种模式菌株的灭活效果。结果表明，与氯化相比，ALDP在灭活所有样本方面都具有优势。在 10 分钟的 ALDP 处理过程中，G 细菌完全被灭活，G 细菌的灭活率超过 4.61 个对数。校园湖泊和污水处理厂出水的细菌灭活率分别超过 99.82%和 97.78%。对于 G 细菌，ALDP 导致的 VBNC 细胞数量比氯化低得多（10∼10 倍）。ALDP 能有效去除抗氯细菌。超过 96.41%的胞内 DNA 和 99.99%的胞外 DNA 被去除，而氯化处理仅为 56.35%和 12.82%。ALDP 比氯化具有更强的破坏细胞结构的能力，这可能是由于存在 ROS（·OH、O 和 O）。GC-MS 分析表明，ALDP 比氯化产生的消毒副产物更少。这些发现为放电等离子体在水消毒中的应用提供了新的见解，它可以补充或替代传统的消毒方法。
