Mechanisms of PFBA toxicity in Chlorella vulgaris: Photosynthesis, oxidative stress, and antioxidant impairment

作者：Zeliang Liu, Xuanlin Cao, Manli Wu, Wenjie Huang, Xia Dong, Xing Chen, Chun Zhang · 发表于：Environmental Research · 年份：2025 · DOI：10.1016/j.envres.2025.121228 · 被引用次数：34 · 研究领域：Per- and polyfluoroalkyl substances research、Algal biology and biofuel production、Analytical chemistry methods development

Perfluorobutanoic acid (PFBA), an emerging alternative to perfluorooctanoic acid (PFOA), has become increasingly prevalent in aquatic ecosystems , yet its ecotoxicological impacts remain poorly understood. This study investigated the aquatic toxicity of PFBA using the freshwater algae Chlorella vulgaris ( C . vulgaris ) as a model organism, employing a 96h pre-exposure assay to determine the median effective concentration followed by acute toxicity experiments analyzing multiple endpoints including growth, photosynthetic parameters, oxidative stress markers, and antioxidant enzyme activities . Computer simulation techniques were utilized to illustrate the underlying molecular mechanisms of PFBA toxicity. The results showed that the 96h-EC 50 value of PFBA was 154.88 mg/L, which is comparable to conventional per- and polyfluoroalkyl substances (PFAS). Acute toxicity experiments revealed a biphasic dose-response relationship to the algal growth with the hormetic effects at the lower concentrations (30.97–92.93 mg/L) but inhibition at the higher levels (123.91–185.86 mg/L) of PFBA. High dosages of PFBA significantly decreased the maximum photosynthetic yield (Fv/Fm) and relative electron transfer rate (rETR), while inducing oxidative stress and inhibiting superoxide dismutase (SOD) and catalase (CAT) activities. Future AlphaFold2 modeling and molecular docking simulations demonstrated the potential binding of PFBA to photosystem II D1 C-terminal processing protease (PSII D1 prot...