Key Laboratory of Pollution Exposure and Health Intervention of Zhejiang Province, College of Biological and Environmental Engineering, Zhejiang Shuren University, Hangzhou 310015, China; College of Environment, Zhejiang University of Technology, Hangzhou 310032, China.
MOE Key Laboratory of Environmental Remediation & Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
Sci Total Environ. 2023 Dec 1;902:165768. doi: 10.1016/j.scitotenv.2023.165768. Epub 2023 Jul 27.
The secondary metabolism of plants is key for mediating responses to environmental stress, but few studies have examined how the relationship between secondary metabolism and the stress response of plants is affected by exposure to antibiotics. Here, we studied the effects of sulfamethoxazole (SMZ) on the secondary metabolism and antioxidant activity of oilseed rape (Brassica napus L.). SMZ significantly affected the growth of rape seedlings. Low and high concentrations of SMZ induced the production of a large number of reactive oxygen species (ROS) in rape seedlings, which damaged cells. SMZ stress altered the activity of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), as well as the content of malondialdehyde (MDA). SMZ promoted the activities of phenylalanine ammonia lyase (PAL), tyrosine ammonia lyase (TAL), cinnamic acid-4-hydroxylase (C4H), and 4-coumaric acid: coenzyme A ligase (4CL) by activating the phenylpropanoid pathway. The content of secondary metabolites changed. The content of phenolic acids and flavonoids increased, and the content of sinapine and anthocyanins was altered to cope with the oxidative damage induced by antibiotics. Transcriptomic and metabolomic analysis showed that differentially expressed genes and differentially expressed metabolites were mainly involved in Phenylpropanoid biosynthesis. SMZ alters the secondary metabolites of rapeseed, which mitigates the deleterious effects of stress, by modulating upstream secondary metabolism pathways and the production of plant hormones involved in signal transduction. In sum, these results provide a new perspective on the effects of SMZ on plants relative to secondary metabolites and improve our understanding of the toxicity of SMZ.
植物的次生代谢对于介导植物对环境胁迫的响应至关重要，但很少有研究探讨抗生素暴露如何影响植物次生代谢与胁迫响应之间的关系。在这里，我们研究了磺胺甲恶唑（SMZ）对油菜（Brassica napus L.）次生代谢和抗氧化活性的影响。SMZ 显著影响油菜幼苗的生长。低浓度和高浓度的 SMZ 诱导油菜幼苗产生大量活性氧（ROS），从而破坏细胞。SMZ 胁迫改变了超氧化物歧化酶（SOD）、过氧化物酶（POD）和过氧化氢酶（CAT）的活性以及丙二醛（MDA）的含量。SMZ 通过激活苯丙烷途径，促进苯丙氨酸解氨酶（PAL）、酪氨酸解氨酶（TAL）、肉桂酸-4-羟化酶（C4H）和 4-香豆酸：辅酶 A 连接酶（4CL）的活性。次生代谢物的含量发生变化。酚酸和类黄酮的含量增加，而芥子碱和花青素的含量发生改变，以应对抗生素诱导的氧化损伤。转录组学和代谢组学分析表明，差异表达基因和差异表达代谢物主要参与苯丙烷生物合成。SMZ 通过调节上游次生代谢途径和参与信号转导的植物激素的产生，改变油菜籽的次生代谢物，从而减轻胁迫的有害影响。总之，这些结果为 SMZ 对植物次生代谢物的影响提供了一个新的视角，并提高了我们对 SMZ 毒性的认识。
