TY  - JOUR
AU  - Gabriel, F. L. P.
AU  - Routledge, E.J.
AU  - Heidlberger, A.
AU  - Rentsch, D.
AU  - Günther, K.
AU  - Giger, W.
AU  - Sumpter, J.P.
AU  - Kohler, H.-P.E.
TI  - Isomer-specific degradation and endocrine disrupting activity of nonylphenols
JO  - Environmental Science & Technology
VL  - 42
SN  - 0013-936X
CY  - Columbus, Ohio
PB  - American Chemical Society
M1  - PreJuSER-432
SP  - 6399 - 6408
PY  - 2008
N1  - This research was supported by the Swiss National Science Foundation within the framework of the National Research Programme NFP50 "Endocrine Disruptors: Relevance to Humans, Animals, and Ecosystems". We thank Dr. Ian Purvis and others at GlaxoSmithKline for kindly supplying the genetically modified yeast strain.
AB  - Degradation of technical nonylphenol by Sphingobium xenophagum Bayram led to a significant shift in the isomers composition of the mixture. By means of gas chromatography-mass spectrometry, we could observe a strong correlation between transformation of individual isomers and their a-substitution pattern, as expressed by their assignment to one of six mass spectrometric groups. As a rule, isomers with less bulkiness at the a-carbon and those with an optimally sized main alkyl chain (4-6 carbon atoms) were degraded more efficiently. By mass spectrometric analysis, we identified the two most recalcitrant main isomers of the technical mixture (Group4) as 4-(1,2-dimethyl-1-propylbutyl) phenols (NP193a and NP193b, which are diastereomers with a bulky alpha-CH3, alpha-CH(CH3)C2H5 substitution. Our experiments with strain Bayram show that the selective enrichment of isomers with bulky a-substitutions observed in nonylphenol fingerprints of natural systems can be caused by microbial ipso-hydroxylation. Based on the yeast estrogen assay (YES), we established an estrogenicity ranking with a variety of single isomers and compared it to rankings obtained with different reporter cell systems. Structure-activity relationships derived from these data suggest that Group 4 isomers have a high estrogenic potency. This indicates a substantial risk that enrichment of highly estrogenic isomers during microbial degradation by ipso-substitution will increase the specific estrogenicity of aging material.
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000258883300019
C6  - pmid:18800507
DO  - DOI:10.1021/es800577a
UR  - https://juser.fz-juelich.de/record/432
ER  -