Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China.
State Key Joint Laboratory of Environmental Simulation and Pollution Control (SKJLESPC), College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
Ecotoxicol Environ Saf. 2019 Jun 15;174:66-74. doi: 10.1016/j.ecoenv.2019.02.066. Epub 2019 Feb 26.
As a persistent organic pollutant listed in the Stockholm Convention, perfluorooctane sulfonate (PFOS) is extremely refractory to degradation under ambient conditions. Its potential ecotoxicity has aroused great concerns and research interests. However, little is known about the toxicity of PFOS on fungus. In this study, the white rot fungus Phanerochaete chrysosporium (P. chrysosporium) was adopted to assess the toxicity of PFOS in liquid culture. The addition of 100 mg/L PFOS potassium salt significantly decreased the fungal biomass by up to 76.4% comparing with un-amended control during the incubation period. The hyphostroma of P. chrysosporium was wizened and its cell membrane was thickened, while its vesicle structure was increased, based on the observation with scanning electron microscope (SEM) and transmission electron microscope (TEM). Nevertheless, the PFOS dosage of below 100 mg/L did not show a considerable damage to the growth of P. chrysosporium. The degradation of malachite green (MG) and 2,4-dichlorophenol (2,4-DCP) by P. chrysosporium was negatively affected by PFOS. At the initial dosage of 100 mg/L PFOS, the decolorization efficiency of MG and the degradation efficiency of 2,4-DCP decreased by 37% and 20%, respectively. This might be attributed to the inhibition of PFOS on MnP and LiP activities. The activities of MnP and LiP decreased by 20.6% and 43.4%, respectively. At a high dosage PFOS (100 mg/L), P. chrysosporium could show a high adsorption of MG but lose its pollutant degradation ability. Transcriptome analysis indicated that PFOS contamination could lead to the change of gene expression in the studied white rot fungus, and the genes regulating membrane structure, cell redox process, and cell transport, synthesis and metabolism were impacted. Membrane damage and oxidative damage were the two main mechanisms of PFOS' toxicity to P. chrysosporium.
作为斯德哥尔摩公约中列出的持久性有机污染物，全氟辛烷磺酸（PFOS）在环境条件下极难降解。其潜在的生态毒性引起了极大的关注和研究兴趣。然而，关于 PFOS 对真菌的毒性知之甚少。在这项研究中，采用白腐真菌糙皮侧耳（P. chrysosporium）在液体培养中评估 PFOS 的毒性。与未添加对照相比，添加 100mg/L 的 PFOS 钾盐在孵育期间使真菌生物量减少了高达 76.4%。糙皮侧耳的菌丝体萎缩，细胞膜增厚，而囊泡结构增加，这是通过扫描电子显微镜（SEM）和透射电子显微镜（TEM）观察得出的。然而，低于 100mg/L 的 PFOS 剂量对糙皮侧耳的生长没有明显的损害。PFOS 对 P. chrysosporium 降解孔雀石绿（MG）和 2,4-二氯苯酚（2,4-DCP）有负面影响。在 100mg/L PFOS 的初始剂量下，MG 的脱色效率和 2,4-DCP 的降解效率分别降低了 37%和 20%。这可能是由于 PFOS 对 MnP 和 LiP 活性的抑制。MnP 和 LiP 的活性分别降低了 20.6%和 43.4%。在高剂量 PFOS（100mg/L）下，P. chrysosporium 可以对 MG 表现出高吸附性，但失去其污染物降解能力。转录组分析表明，PFOS 污染会导致所研究的白腐真菌基因表达的变化，调节膜结构、细胞氧化还原过程以及细胞运输、合成和代谢的基因受到影响。膜损伤和氧化损伤是 PFOS 对 P. chrysosporium 毒性的两个主要机制。
