{"title":"Assessing the effectiveness and mechanisms of Fe/PS, Fe/H2O2, and O3 treatment for water disinfection: Spotlight on VBNC bacteria","authors":"Zheng Qi , Zaihui Huang , Chunguang Liu","doi":"10.1016/j.jes.2024.05.023","DOIUrl":null,"url":null,"abstract":"<div><p>Advanced oxidation processes (AOPs) exhibit significant potential for water disinfection due to their generation of large quantities of highly oxidizing free radicals. However, the neglect of viable but nonculturable (VBNC) cells obscures their true disinfection efficacy and potential environmental health risks. Therefore, the study evaluated the disinfection effectiveness and mechanisms of typical AOPs, including Fe/H<sub>2</sub>O<sub>2</sub>, Fe/persulfate (PS), and O<sub>3</sub>, from the perspective of the production of VBNC bacteria. The results indicate that Fe/PS exhibits the strongest bacterial inactivation rate (99.94%), and the cells lose their ability to reactivate. Fe/H<sub>2</sub>O<sub>2</sub> and O<sub>3</sub> induce more cells to enter the VBNC state compared to Fe/PS. Moreover, different AOPs result in varying levels of free radical production and utilization efficiency, with SO<sub>4</sub><sup>•−</sup> and O<sub>3</sub> exhibiting greater selectivity in deactivating bacteria compared to HO<sup>•</sup>. The inhibition of VBNC bacteria production by Fe/PS treatment may be attributed to the combined action of HO<sup>•</sup> and SO<sub>4</sub><sup>•−</sup> on microorganisms, leading to oxidative stress and metabolic disruption in bacteria through the inhibition of biofilm formation and aminoacyl-tRNA biosynthesis (<em>p</em> < 0.05), thereby causing direct bacterial death rather than entry into the VBNC state. In contrast, Fe/H<sub>2</sub>O<sub>2</sub> and O<sub>3</sub> result in the upregulation of the metabolism of alanine, aspartate, and glutamate, as well as styrene degradation capacity by the bacteria, leading to the production of more VBNC bacteria. Overall, the study offers insights into mitigating potential biological risks in water disinfection and developing environmentally friendly and efficient disinfection technologies.</p></div>","PeriodicalId":15788,"journal":{"name":"Journal of Environmental Sciences-china","volume":"152 ","pages":"Pages 389-400"},"PeriodicalIF":5.9000,"publicationDate":"2024-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Environmental Sciences-china","FirstCategoryId":"93","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1001074224002626","RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
Advanced oxidation processes (AOPs) exhibit significant potential for water disinfection due to their generation of large quantities of highly oxidizing free radicals. However, the neglect of viable but nonculturable (VBNC) cells obscures their true disinfection efficacy and potential environmental health risks. Therefore, the study evaluated the disinfection effectiveness and mechanisms of typical AOPs, including Fe/H2O2, Fe/persulfate (PS), and O3, from the perspective of the production of VBNC bacteria. The results indicate that Fe/PS exhibits the strongest bacterial inactivation rate (99.94%), and the cells lose their ability to reactivate. Fe/H2O2 and O3 induce more cells to enter the VBNC state compared to Fe/PS. Moreover, different AOPs result in varying levels of free radical production and utilization efficiency, with SO4•− and O3 exhibiting greater selectivity in deactivating bacteria compared to HO•. The inhibition of VBNC bacteria production by Fe/PS treatment may be attributed to the combined action of HO• and SO4•− on microorganisms, leading to oxidative stress and metabolic disruption in bacteria through the inhibition of biofilm formation and aminoacyl-tRNA biosynthesis (p < 0.05), thereby causing direct bacterial death rather than entry into the VBNC state. In contrast, Fe/H2O2 and O3 result in the upregulation of the metabolism of alanine, aspartate, and glutamate, as well as styrene degradation capacity by the bacteria, leading to the production of more VBNC bacteria. Overall, the study offers insights into mitigating potential biological risks in water disinfection and developing environmentally friendly and efficient disinfection technologies.
期刊介绍:
The Journal of Environmental Sciences is an international journal started in 1989. The journal is devoted to publish original, peer-reviewed research papers on main aspects of environmental sciences, such as environmental chemistry, environmental biology, ecology, geosciences and environmental physics. Appropriate subjects include basic and applied research on atmospheric, terrestrial and aquatic environments, pollution control and abatement technology, conservation of natural resources, environmental health and toxicology. Announcements of international environmental science meetings and other recent information are also included.