Open AccessEffects of organic ligands on Pb absorption and speciation changes in Arabidopsis as determined by micro X‐ray fluorescence and X‐ray absorption near‐edge structure analysis
Author(s) -
Shen Ya Ting,
Song Yu Fang
Publication year - 2017
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s1600577517001941
Subject(s) - genetic algorithm , absorption (acoustics) , arabidopsis , bioavailability , arabidopsis thaliana , chemistry , environmental chemistry , hyperaccumulator , fluorescence , xanes , extended x ray absorption fine structure , ligand (biochemistry) , nuclear chemistry , phytoremediation , absorption spectroscopy , heavy metals , materials science , biology , spectroscopy , biochemistry , gene , bioinformatics , physics , quantum mechanics , evolutionary biology , mutant , composite material , receptor
Pb can pass through the food chain via plants and threaten human health, which has attracted widespread attention. Changes in Pb speciation affect its bioavailability in soils and water. However, whether organic ligands can change the uptake and mobility of Pb in plants and increase or decrease Pb bioavailability remains uncertain. To reveal the roles of organic and inorganic Pb in Pb metabolism in plants, the localization and speciation changes of Pb in Arabidopsis thaliana plants grown in organic and inorganic Pb were characterized by synchrotron radiation micro X‐ray fluorescence and X‐ray absorption near‐edge structure, respectively. These results demonstrated that Arabidopsis absorbed more Pb from Pb(NO 3 ) 2 than Pb(CH 3 COO) 2 at the same exposure concentration. A higher percentage of Pb‐citrate was found in Arabidopsis exposed to inorganic Pb solution, which suggested that Pb‐citrate was the main complex for root‐to‐shoot transportation in Arabidopsis exposed to inorganic Pb solutions. Pb complexed with the organic ligand CH 3 COO − significantly inhibited primary root growth and lateral root development, while, at the same time, Pb was blocked by root hairs, which represented another way to reduce Pb absorption and protect the plant from biotoxicity.