title: The characterization of dissolved organic matter extracted from different sources and their influence on cadmium uptake by Microcystis aeruginosa.
abstract: The present study examines the uptake of the heavy metal cadmium (Cd) by Microcystis aeruginosa in the presence of dissolved organic matter (DOM) from different origins. The DOM used in the present study were extracted from soil, sediment taken from Meiliang Bay at Taihu Lake, and from M. aeruginosa cultured in the laboratory. The 3 different DOM samples were characterized using ultraviolet-visible absorption spectroscopy and Fourier transform infrared spectroscopy. The excitation-emission matrix (EEM) fluorescence spectroscopy was used to characterize the interactions of DOM with Cd2+. The results showed that all types of DOM extracted from the 3 sources in the present study exhibited aliphatic and aromatic characteristics and contained hydroxyls, carbonyls, phenols, carboxyls, carbohydrates, amines, and ethers. Humic acids and fulvic acids proved to be the major components of DOM. The sediment DOM had the highest degrees of aromatization and humification among the samples. The results also showed that sediment and soil DOM samples had lower molecular weights than M. aeruginosa DOM. The DOM could react with Cd2+by complexing to alter Cd speciation. When exposed to Cd, EEM fluorescence intensities of all 3 DOM types had a significant decrease, and the intracellular Cd content improved with increasing Cd concentrations. The addition of DOM greatly enhanced Cd uptake by M. aeruginosa compared with the control group. Environ Toxicol Chem 2017;36:1856-1863. © 2017 SETAC.
authors.affiliation: Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, School of Environment, Hohai University, Nanjing, China.
authors.forename: Lixiao
authors.initials: L
authors.lastname: Ni
authors.affiliation: Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, School of Environment, Hohai University, Nanjing, China.
authors.forename: Lili
authors.initials: L
authors.lastname: Su
authors.affiliation: Department of Environmental Science and Engineering, School of Geography Science, Nanjing Normal University, Nanjing, China.
authors.forename: Shiyin
authors.initials: S
authors.lastname: Li
authors.affiliation: Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, School of Environment, Hohai University, Nanjing, China.
authors.forename: Peifang
authors.initials: P
authors.lastname: Wang
authors.affiliation: Anhui Lvtong Engineering Design Consulting, Wuhu, China.
authors.forename: Dandan
authors.initials: D
authors.lastname: Li
authors.affiliation: Anhui Urban Construction Design & Research Institute, Hefei, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Ye
authors.affiliation: Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, School of Environment, Hohai University, Nanjing, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, School of Environment, Hohai University, Nanjing, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, School of Environment, Hohai University, Nanjing, China.
authors.forename: Yiping
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, School of Environment, Hohai University, Nanjing, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Wang
mesh_terms: D061006:Bays; D002104:Cadmium / Q000737:chemistry / Q000378:metabolism*; D002681:China; D019015:Geologic Sediments / Q000737:chemistry; D060106:Lakes; D046931:Microcystis / Q000737:chemistry* / Q000378:metabolism; D009930:Organic Chemicals / Q000032:analysis / Q000302:isolation & purification / Q000378:metabolism*; D012987:Soil / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D009930:Organic Chemicals; D012987:Soil; D002104:Cadmium
keywords: Cadmium; Characterization; Dissolved organic matter; Microcystis aeruginosa; Uptake