Comparison of the toxicity of silver nanoparticles and silver ions on the growth of terrestrial plant model Arabidopsis thaliana  

作　　者：Haifeng Qian Xiaofeng Peng Xiao Han Jie Ren Liwei Sun Zhengwei Fu 

机构地区：[1]College of Biological and Environmental Engineering, Zhejiang University of Technology

出　　处：《Journal of Environmental Sciences》2013年第9期1947-1955,共9页环境科学学报（英文版）

基　　金：supported by the National Basic Research Program of China (No. 2010CB126100, 2009CB119006);the National Natural Science Foundation of China (No.21077093, 21277127)

摘　　要：Silver nanoparticles （AgNPs） are one of the most widely used nanomaterials, but the mechanism of AgNP toxicity in terrestrial plants is still unclear. We compared the toxic effects of AgNPs and Ag＋ on Arabidopsis thaliana at the physiological, ultrastructural and molecular levels. AgNPs did not affect seed germination; however, they showed stronger inhibitory effect on root elongation than Ag＋ . The results of transmission electron microscopy and metal content analysis showed that AgNPs could be accumulated in leaves. These absorbed AgNPs disrupted the thylakoid membrane structure and decreased chlorophyll content, which can inhibit plant growth. By comparison, a small amount of Ag＋ was absorbed by seedlings, and it did not pronouncedly affect chloroplast structure and other metal ion absorption as AgNPs did. Compared with Ag＋ , AgNPs could alter the transcription of antioxidant and aquaporin genes, indicating that AgNPs changed the balance between the oxidant and antioxidant systems, and also affected the homeostasis of water and other small molecules within the plant body. All the data from physiological, ultrastructural and molecular levels suggest that AgNPs were more toxic than Ag＋ .Silver nanoparticles （AgNPs） are one of the most widely used nanomaterials, but the mechanism of AgNP toxicity in terrestrial plants is still unclear. We compared the toxic effects of AgNPs and Ag＋ on Arabidopsis thaliana at the physiological, ultrastructural and molecular levels. AgNPs did not affect seed germination; however, they showed stronger inhibitory effect on root elongation than Ag＋ . The results of transmission electron microscopy and metal content analysis showed that AgNPs could be accumulated in leaves. These absorbed AgNPs disrupted the thylakoid membrane structure and decreased chlorophyll content, which can inhibit plant growth. By comparison, a small amount of Ag＋ was absorbed by seedlings, and it did not pronouncedly affect chloroplast structure and other metal ion absorption as AgNPs did. Compared with Ag＋ , AgNPs could alter the transcription of antioxidant and aquaporin genes, indicating that AgNPs changed the balance between the oxidant and antioxidant systems, and also affected the homeostasis of water and other small molecules within the plant body. All the data from physiological, ultrastructural and molecular levels suggest that AgNPs were more toxic than Ag＋ .

关 键 词：silver nanoparticles Ag＋ Arabidopsis thaliana gene transcript antioxidant enzyme AQUAPORINS 

分 类 号：X173[环境科学与工程—环境科学] TB383.1[一般工业技术—材料科学与工程]