Ali Shahid, Bai Yongsheng, Zhang Junliang, Zada Shah, Khan Naeem, Hu Zhangli, Tang Yulin
Guangdong Provincial Key Laboratory for Plant Epigenetics, Shenzhen Engineering Laboratory for Marine Algal Biotechnology, Shenzhen Public Service Platform of Collaborative Innovation for Marine Algae Industry, Longhua Institute of Innovative Biotechnology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, 518060, Guangdong, China; Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China.
Guangdong Provincial Key Laboratory for Plant Epigenetics, Shenzhen Engineering Laboratory for Marine Algal Biotechnology, Shenzhen Public Service Platform of Collaborative Innovation for Marine Algae Industry, Longhua Institute of Innovative Biotechnology, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, 518060, Guangdong, China.
Plant Physiol Biochem. 2024 Jan;206:108126. doi: 10.1016/j.plaphy.2023.108126. Epub 2023 Nov 2.
Heavy metal cadmium (Cd) hinders plants' growth and productivity by causing different morphological and physiological changes. Nanoparticles (NPs) are promising for raising plant yield and reducing Cd toxicity. Nonetheless, the fundamental mechanism of nanoparticle-interfered Cd toxicity in Brassica parachineses L. remains unknown. A novel ZnO nanoparticle (ZnO-NPs) was synthesized using a microalgae strain (Chlorella pyrenoidosa) through a green process and characterized by different standard parameters through TEM, EDX, and XRD. This study examines the effect of different concentrations of ZnO-NPs (50 and 100 mgL) in B. parachineses L. under Cd stress through ultra-high-performance liquid chromatography/high-resolution mass spectrometry-based untargeted metabolomics profiling. In the presence of Cd toxicity, foliar spraying with ZnO-NPs raised Cu, Fe, Zn, and Mg levels in the roots and/or leaves, improved seedling development, as demonstrated by increased plant height, root length, and shoot and root fresh weight. Furthermore, the ZnO-NPs significantly enhanced the photosynthetic pigments and changed the antioxidant activities of the Cd-treated plants. Based on a metabolomics analysis, 481 untargeted metabolites were accumulated in leaves under normal and Cd-stressed conditions. These metabolites were highly enriched in producing organic acids, amino acids, glycosides, flavonoids, nucleic acids, and vitamin biosynthesis. Surprisingly, ZnO-NPs restored approximately 60% of Cd stress metabolites to normal leaf levels. Our findings suggest that green synthesized ZnO-NPs can balance ions' absorption, modulate the antioxidant activities, and restore more metabolites associated with plant growth to their normal levels under Cd stress. It can be applied as a plant growth regulator to alleviate heavy metal toxicity and improve crop yield in heavy metal-contaminated regions.
重金属镉（Cd）通过引起不同的形态和生理变化来阻碍植物生长和生产力。纳米颗粒（NPs）有望提高植物产量并降低镉毒性。然而，纳米颗粒干扰镉对青菜（Brassica parachineses L.）毒性的基本机制仍然未知。利用微藻菌株（小球藻（Chlorella pyrenoidosa））通过绿色工艺合成了一种新型氧化锌纳米颗粒（ZnO-NPs），并通过透射电子显微镜（TEM）、能量散射X射线光谱（EDX）和X射线衍射（XRD）等不同标准参数对其进行了表征。本研究通过基于超高效液相色谱/高分辨率质谱的非靶向代谢组学分析，研究了不同浓度（50和100 mg/L）的ZnO-NPs对镉胁迫下青菜的影响。在镉毒性存在的情况下，叶面喷施ZnO-NPs提高了根和/或叶中的铜、铁、锌和镁含量，改善了幼苗发育，表现为株高、根长以及地上部和根部鲜重增加。此外，ZnO-NPs显著提高了光合色素含量，并改变了镉处理植物的抗氧化活性。基于代谢组学分析，在正常和镉胁迫条件下，叶片中积累了481种非靶向代谢物。这些代谢物在有机酸、氨基酸、糖苷、黄酮类、核酸和维生素生物合成方面高度富集。令人惊讶的是，ZnO-NPs使约60%的镉胁迫代谢物恢复到正常叶片水平。我们的研究结果表明，绿色合成的ZnO-NPs可以平衡离子吸收，调节抗氧化活性，并在镉胁迫下将更多与植物生长相关的代谢物恢复到正常水平。它可以作为一种植物生长调节剂，用于减轻重金属毒性并提高重金属污染地区的作物产量。
