School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, China.
School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, China; Engineering Research Center of Biomass Materials, Ministry of Education of, SWUST, Mianyang, 621010, China.
Chemosphere. 2021 Oct;281:130842. doi: 10.1016/j.chemosphere.2021.130842. Epub 2021 May 18.
The aim of this study was to reveal the mechanism underlying the toxicity of TNT (trinitrotoluene), RDX (cyclotrimethylene trinitroamine), and HMX (cyclotetramethylene tetranitramine) explosives pollution in plants. Here, the effects of exposure to these three explosives were examined on chlorophyll fluorescence, antioxidant enzyme activity, and the metabolite spectrum in alfalfa (Medicago sativa) plants. The degradation rates for TNT, RDX, and HMX by alfalfa were 26.8%, 20.4%, and 18.4%, respectively, under hydroponic conditions. TNT caused damage to the microstructure of the plant roots and inhibited photosynthesis, whereas RDX and HMX induced only minor changes. Exposure to any of the three explosives caused disturbances in the oxidase system. Non-targeted metabolomics identified a total of 6185 metabolites. TNT exposure induced the appearance of 609 differentially expressed metabolites (189 upregulated, 420 downregulated), RDX exposure induced 197 differentially expressed metabolites (155 upregulated and 42 downregulated), and HMX induced 234 differentially expressed metabolites (132 upregulated and 102 downregulated). Of these differentially expressed metabolites, lipids and lipid-like molecules were the main metabolites induced by explosives poisoning. TNT mainly caused significant changes in the alanine, aspartate, and glutamate metabolism metabolic pathways, RDX mainly caused disorders in the arginine biosynthesis metabolic pathway, and HMX disrupted the oxidative phosphorylation metabolic pathway. Taken together, the results show that exposure to TNT, RDX, and HMX leads to imbalances in plant photosynthetic characteristics and antioxidant enzyme systems, changes the basic metabolism of plants, and has significant ecotoxicity effects.
本研究旨在揭示 TNT（三硝基甲苯）、RDX（环三亚甲基三硝胺）和 HMX（环四亚甲基四硝胺）爆炸物污染对植物毒性的作用机制。在此，研究了暴露于这三种爆炸物对紫花苜蓿（Medicago sativa）植物叶绿素荧光、抗氧化酶活性和代谢物谱的影响。在水培条件下，紫花苜蓿对 TNT、RDX 和 HMX 的降解率分别为 26.8%、20.4%和 18.4%。TNT 破坏了植物根系的微观结构并抑制了光合作用，而 RDX 和 HMX 仅引起轻微变化。暴露于这三种爆炸物中的任何一种都会干扰氧化酶系统。非靶向代谢组学共鉴定出 6185 种代谢物。TNT 暴露导致 609 种差异表达代谢物（189 种上调，420 种下调）出现，RDX 暴露导致 197 种差异表达代谢物（155 种上调，42 种下调）出现，HMX 诱导 234 种差异表达代谢物（132 种上调，102 种下调）出现。在这些差异表达的代谢物中，脂质和类脂分子是爆炸物中毒引起的主要代谢物。TNT 主要导致丙氨酸、天冬氨酸和谷氨酸代谢途径发生显著变化，RDX 主要导致精氨酸生物合成代谢途径紊乱，HMX 破坏氧化磷酸化代谢途径。综上所述，这些结果表明，暴露于 TNT、RDX 和 HMX 会导致植物光合特性和抗氧化酶系统失衡，改变植物的基础代谢，具有显著的生态毒性效应。
