Abstract
The reactions of glutathione (GSH) with polybrominated diphenyl ethers (PBDEs) quinones with different degrees of bromination on the PBDEs ring were studied. Liquid chromatography coupled with mass spectrometric (LC-MS) analysis showed that four types of adducts were formed from the reaction of each PBDEs quinone (PBDE-Q) with GSH. The proposed reaction pathway was confirmed using ion trap-MS/MS technique. Our results demonstrate that adduct-1 was formed following the Michael Addition, a reaction of the sulfhydryl group from GSH with electron deficient carbon from PBDEs-Q ring. Compared with other carbons on the quinone ring, carbon in position 6 has a smaller steric hindrance, thus the addition reaction is likely to occur in that position. Hydrated quinone-GSH adduct-1 is easily oxidized to generate an adduct-2 in an aqueous solution. Substitution reaction from bromine atom on adduct-2 quinone ring with sulfhydryl group from GSH further generates adduct-3 that is unstable and can be readily hydrolyzed to adduct-4 in aqueous solution. Both adduct-1 and adduct-4 were unstable as well, immediately oxidized to adduct-2 and adduct-3 in the air, respectively. The results reveal that brominated quinones undergo a rapid non-enzymatic debromination upon reaction with GSH, and open a new view for our understanding on mechanism of metabolism and the toxicity of this class of compounds.
Original language | English |
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Pages (from-to) | 365-370 |
Number of pages | 6 |
Journal | Chemosphere |
Volume | 120 |
DOIs | |
Publication status | Published - 1 Feb 2015 |
Scopus Subject Areas
- Environmental Engineering
- Environmental Chemistry
- Chemistry(all)
- Pollution
- Health, Toxicology and Mutagenesis
User-Defined Keywords
- GSH
- LC-MS
- PBDE-quinone
- PBDEs