Institute of Marine Science and Technology, Shandong University, Qingdao, 266237, PR China.
Institute of Marine Science and Technology, Shandong University, Qingdao, 266237, PR China.
Environ Pollut. 2023 Jan 1;316(Pt 1):120544. doi: 10.1016/j.envpol.2022.120544. Epub 2022 Nov 2.
The toxicity of microplastics (MPs) to marine microalgae has raised much concern. However, research at metabolic level is quite limited. In this study, the physiological and metabolic effects of polystyrene (PS) and aged polystyrene (A-PS) MPs on Dunaliella salina were investigated. Both PS and A-PS inhibited the growth of microalgae, but promoted the pigment synthesis in algal cells. The oxidative stress analysis indicated that PS and A-PS induced high production of reactive oxygen species (ROS), and caused oxidative damage to algal cells. Particularly, the highest ROS level in PS and A-PS groups were 1.70- and 2.24-fold of that in the control group, respectively. Untargeted metabolomics analysis indicated that PS and A-PS significantly increased the differential metabolites. Compared with the control group, the significant upregulation of glycerophospholipids metabolites illustrated that severe membrane lipid peroxidation occurred in the MPs groups. Metabolic pathways analysis showed that PS and A-PS perturbed the amino acid-related metabolic pathways. In particular, the amino acid biosynthesis and ATP-binding cassette (ABC) transporter pathways were significantly upregulated, thus promoting nitrogen storage and transmembrane transport in Dunaliella salina. Transmembrane transport requires a large amount of ATP; as a result, algal cell division is inhibited. In addition, A-PS stimulated more active glutathione metabolism than PS. These results enrich the understanding of the toxicity of PS MPs to microalgae at the metabolic level, and are helpful for further assessing the ecological impacts of MPs on microalgae.
微塑料（MPs）对海洋微藻的毒性引起了广泛关注。然而，在代谢水平上的研究相当有限。在这项研究中，研究了聚苯乙烯（PS）和老化聚苯乙烯（A-PS） MPs 对盐生杜氏藻的生理和代谢影响。PS 和 A-PS 均抑制微藻生长，但促进藻细胞中色素的合成。氧化应激分析表明，PS 和 A-PS 诱导活性氧（ROS）的大量产生，并对藻细胞造成氧化损伤。特别是，PS 和 A-PS 组中的 ROS 水平最高分别比对照组高 1.70 倍和 2.24 倍。非靶向代谢组学分析表明，PS 和 A-PS 显著增加了差异代谢物。与对照组相比，甘油磷脂代谢物的显著上调表明 MPs 组发生了严重的膜脂过氧化。代谢途径分析表明，PS 和 A-PS 扰乱了与氨基酸相关的代谢途径。特别是，氨基酸生物合成和 ABC 转运蛋白途径显著上调，从而促进了盐生杜氏藻中的氮储存和跨膜运输。跨膜运输需要大量的 ATP；因此，抑制了藻类细胞的分裂。此外，A-PS 刺激的谷胱甘肽代谢比 PS 更活跃。这些结果丰富了对 PS MPs 对微藻在代谢水平上的毒性的认识，并有助于进一步评估 MPs 对微藻的生态影响。
