Impacts of lignin nanoparticles as antibacterial agents on the composition of biofilms in water treatment
File(s)
Accepted version
Author(s)
Zhang, Jiesi
Li, Yufei
Graham, Nigel
Liu, Minmin
Yu, Wenzheng
Type
Journal Article
Abstract
The development of green, high-efficiency biocides is critical for the effective control of microbial biofilms in water treatment processes. In this study, lignin nanoparticles (NPs), with an average size of around 30 nm, were synthesized via a ‘green’ process and applied as biocides. A gravity-driven ultrafiltration membrane system was employed to investigate their effects on biofilm composition. The results showed that when the dosage of lignin NPs was only 1 mg C/L, the abundances of bacteria and fungi in the membrane biofilms were reduced by >98%, and the total protein and polysaccharide contents in the extracellular polymeric substance (EPS) decreased significantly, demonstrating remarkable advantages. The core antimicrobial mechanism involves two synergistic effects: (1) Hydrogen bonds are formed between the hydrophilic carboxyl groups on lignin nanoparticles (NPs) and EPS-components of microbial cell walls, directly inhibiting microbial viability and proliferation while reducing EPS secretion; (2) Lignin NPs are oxidized to aromatic derivatives, with benzene rings converted into hydroxyl‑enriched phenolic structures, and the concurrent elevation of carbonyl (C=O) groups in extracellular proteins enhances hydrophobicity. The oxidized lignin NPs then amplify antimicrobial efficacy via hydrophobic associations with these modified aromatic compounds and proteins. This work provides a novel approach and new insights into the rational design of green biocides and the regulation of membrane biofilms.
Date Issued
2026-04-15
Date Acceptance
2026-02-06
Citation
Water Research, 2026, 294
ISSN
0043-1354
Publisher
Elsevier BV
Journal / Book Title
Water Research
Volume
294
Copyright Statement
Copyright © 2026 Elsevier Ltd. This is the author’s accepted manuscript made available under a CC-BY licence in accordance with Imperial’s Research Publications Open Access policy (www.imperial.ac.uk/oa-policy)
License URL
Publication Status
Published
Article Number
125533
Date Publish Online
2026-02-07