College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, PR China.
State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, PR China; College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, PR China.
Sci Total Environ. 2024 Nov 20;952:175726. doi: 10.1016/j.scitotenv.2024.175726. Epub 2024 Aug 22.
Per- and poly-fluoroalkyl substances (PFAS) are an emerging class of persistent organic pollutants that are widespread in aquatic ecosystems and pose a serious threat to aquatic organisms. It is thus crucial to explore the toxicity mechanisms of PFAS to submerged macrophytes and biofilms. In this study, Vallisneria natans (V. natans) was exposed to environmentally relevant concentrations of perfluorooctanoic acid (PFOA) and perfluorooctane sulphonate (PFOS). Results showed that PFAS induced the excessive production of reactive oxygen species, triggering antioxidant responses. V. natans exhibited an improved stress tolerance by altering the biosynthesis of several plant secondary metabolites and the histidine, arginine, proline pathways in response to PFAS exposure. Moreover, PIP1-1, PIP2-2, SLAH1 and SLAH2 genes were upregulated, indicating the activation of aquaporins and slow-type anion channels. The uptake of PFOA and PFOS by V. natans was 41.74 % and 52.31 %, respectively. Notably, PFAS bound to functional proteins (GSTF10), promoting the detoxification of plants. Exposure to PFAS also altered the structure of biofilms by inducing the synthesis of large amounts of polysaccharides and proteins. The diversity and richness of the microbial community within periphytic biofilms changed significantly. These results provide a comprehensive description of the responses of aquatic plants and periphytic biofilms to PFAS and the removal mechanism of PFAS, contributing to the environmental risk assessments and removal of PFAS in aquatic ecosystems.
全氟和多氟烷基物质（PFAS）是一类新兴的持久性有机污染物，广泛存在于水生生态系统中，对水生生物构成严重威胁。因此，探索 PFAS 对沉水植物和生物膜的毒性机制至关重要。本研究采用环境相关浓度的全氟辛酸（PFOA）和全氟辛烷磺酸（PFOS）暴露于菹草（Vallisneria natans）。结果表明，PFAS 诱导活性氧的过度产生，引发抗氧化反应。V. natans 通过改变几种植物次生代谢物的生物合成以及组氨酸、精氨酸、脯氨酸途径来应对 PFAS 暴露，从而提高了其胁迫耐受能力。此外，PIP1-1、PIP2-2、SLAH1 和 SLAH2 基因上调，表明水通道蛋白和慢型阴离子通道的激活。V. natans 对 PFOA 和 PFOS 的摄取分别为 41.74%和 52.31%。值得注意的是，PFAS 与功能蛋白（GSTF10）结合，促进了植物的解毒作用。PFAS 的暴露还通过诱导大量多糖和蛋白质的合成改变了生物膜的结构。周丛生物膜内微生物群落的多样性和丰富度发生了显著变化。这些结果全面描述了水生植物和周丛生物膜对 PFAS 的响应以及 PFAS 的去除机制，为水生生态系统中 PFAS 的环境风险评估和去除提供了依据。
