Effective inactivation of fungal spores by the combined UV/PAA: Synergistic effect and mechanisms

Xiangqian Xu; Jie Zuo; Qiqi Wan; Ruihua Cao; Huining Xu; Kai Li; Tinglin Huang; Gang Wen; Jun Ma

doi:10.1016/j.jhazmat.2022.128515

Effective inactivation of fungal spores by the combined UV/PAA: Synergistic effect and mechanisms

J Hazard Mater. 2022 May 15:430:128515. doi: 10.1016/j.jhazmat.2022.128515. Epub 2022 Feb 18.

Authors

Xiangqian Xu¹, Jie Zuo¹, Qiqi Wan¹, Ruihua Cao¹, Huining Xu¹, Kai Li¹, Tinglin Huang¹, Gang Wen², Jun Ma³

Affiliations

¹ Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China.
² Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province, Xi'an University of Architecture and Technology, Xi'an 710055, China. Electronic address: hitwengang@163.com.
³ School of Environment, Harbin Institute of Technology, China.

PMID: 35739689
DOI: 10.1016/j.jhazmat.2022.128515

Abstract

Peracetic acid (PAA) can effectively inactivate fungi in water, while may pose a potential risk of regrowth after disinfection. The inactivation kinetic and mechanism of fungal spores by combined UV and PAA (UV/PAA) was investigated in this study. The results showed that synergistic factor of the inactivation of A. niger and A. flavus was 1.44 and 1.37, which indicated significant synergistic effect of UV/PAA. The k of A. niger and A. flavus was similar at pH 5.0 and 7.0, while decreased 60.00% and 39.13% at pH 9.0 compared with that at pH 7.0. The effect of HA concentration on the inactivation efficiency of fungal spores by UV/PAA was negative, while the effect of PAA concentration was positive. The membrane permeabilized cell of A. niger and A. flavus caused by UV/PAA was 17.0% and 31.7%, which was higher than that caused by PAA and UV alone. The changes of morphology of fungal spores and the leakage of intracellular material indicated that the damage of cell structure caused by UV/PAA system was more serious than that of UV or PAA alone. In addition, the four parts that contributed in UV/PAA system was in the following order: UV > radical > PAA > synergistic effect. The inactivation efficiency of combined UV and chlorine (UV/Cl₂) was higher than that of UV/PAA. Furthermore, the typical order of the inactivation efficiency in different matrix was: phosphate buffer solution > surface water > secondary effluent. The regrowth potential of fungal spores after UV/PAA treatment was significantly lower than that by PAA alone, indicating that UV/PAA could decrease the microbial regrowth potential after PAA disinfection alone.

Keywords: Combined inactivation; Fungal spores; Peracetic acid; Regrowth; Synergistic effect; Ultraviolet.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Disinfection / methods
Peracetic Acid*
Spores, Fungal
Ultraviolet Rays
Water
Water Purification* / methods

Substances

Water
Peracetic Acid