In vivo biotransformation of 3,3',4,4'-tetrachlorobiphenyl by whole plants-poplars and switchgrass.
Polychlorinated biphenyls (PCBs) are widely distributed persistent organic pollutants. In vitro research has shown that plant cell cultures might transform lower chlorinated congeners to hydroxylated PCBs, but there are few studies on in vivo metabolism of PCBs by intact whole plants. In this research, poplar plants (Populus deltoides x nigra, DN34) and switchgrass (Panicum vigratum, Alamo) were hydroponically exposed to 3,3',4,4'-tetrachlorobiphenyl (CB77). Metabolism in plants occurred rapidly, and metabolites were detected after only a 24 h exposure. Rearrangement of chlorine atoms and dechlorination of CB77 by plants was unexpectedly observed. In addition, poplars were able to hydroxylate CB77 and the metabolite 6-hydroxy-3,3,4,4'-tetrachlorobiphenyl 6-OH-CB77) was identified and quantified. Hybrid poplar was able to hydroxylate CB77, but switchgrass was not, suggesting that enzymatic transformations are plant specific. Sulfur-containing metabolites (from the action of sulfotransferases) were investigated in this study, but they were not detected in either poplar or switchgrass.
State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085, China. liujy@rcees.ac.cn
Jiyan
J
Liu
Dingfei
D
Hu
Guibin
G
Jiang
Jerald L
JL
Schnoor
D001673:Biodegradation, Environmental; D015394:Molecular Structure; D008897:Panicum / Q000378:metabolism*; D011078:Polychlorinated Biphenyls / Q000737:chemistry / Q000378:metabolism*; D032107:Populus / Q000378:metabolism*; D014867:Water / Q000737:chemistry
D014867:Water; D011078:Polychlorinated Biphenyls; C028451:3,4,3',4'-tetrachlorobiphenyl