Identification of hydroxylated metabolites of 3,3′,4,4′-tetrachlorobiphenyl and metabolic pathway in whole poplar plants

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• 作者：Guangshu Zhai ; Hans-Joachim Lehmler ; Jerald L. Schnoor
• 关键词：3 ; 3′ ; 4 ; 4′ ; -Tetrachlorobiphenyl ; Hydroxylated metabolite ; Poplar ; Pathway
• 刊名：Chemosphere
• 出版年：2010
• 出版时间：September 2010
• 年：2010
• 卷：81
• 期：4
• 页码：523-528
• 全文大小：318 K

文摘

Polychlorinated biphenyls (PCBs) can be metabolized to hydroxylated polychlorinated biphenyls (OH-PCBs) as reported in a number of animal studies. However, there are few studies on OH-PCBs in vivo in whole plants. In order to explore the formation of OH-PCBs in whole plants in detail, poplars (Populus deltoides × nigra, DN34) were exposed to 3,3′,4,4′-tetrachlorobiphenyl (CB77) in hydroponic solution. Poplars are widely used in phytoremediation applications and the complete genome has been sequenced. In this research, a HPLC-MS method was developed to directly determine the hydroxylated metabolites of CB77 (OH-CB77s), avoiding the experimental errors introduced by derivatization pretreatments required by gas chromatography-based methods. Three potential hydroxylated metabolites of CB77, including 6-hydroxy-3,3′,4,4′-tetrachlorobiphenyl (6OH-CB77), 5-hydroxy-3,3′,4,4′-tetrachlorobiphenyl (5OH-CB77) and 4′-hydroxy-3,3′,4,5′-tetrachlorobiphenyl (4′OH-CB79), were determined in poplar tissues. The major product, 6OH-CB77, was detected in the roots, bottom bark, bottom wood, middle bark and middle wood for the whole poplar plants, but the minor product, 5OH-CB77, was detected only in the poplar roots. The concentration of 6OH-CB77 was about 10 times greater than that of 5OH-CB77 in the roots. However, the major mammalian metabolite, 4′OH-CB79 was not detected in any of the samples. The results suggest that the hydroxylated metabolic pathway of CB77 is via an epoxide intermediate in poplar.