Parameters influencing biotransformation rates of phenylurea herbicides by soil microorganisms

被引:17
作者
Berger, BM [1 ]
机构
[1] Univ Gottingen, Inst Pflanzenpathol & Pflanzenschutz, D-37077 Gottingen, Germany
关键词
biotransformation; phenylureas; metabolism; structure-reactivity relationships; microorganisms;
D O I
10.1006/pest.1998.2324
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
The biotransformation of phenylurea herbicides and some of their most prominent degradates by different soil microorganisms was investigated. Most soil fungi, bur only some soil bacteria, were able to reduce the herbicide concentration in the culture medium. Biotransformation rates of the compounds were different. Identification of the products demonstrated that N-demethylation was the most common initial biotransformation step. Cleavage of the urea bridge was only observed by bacteria. Sorption of the compounds to the mycelium or cells was different among the microorganisms investigated, but studies with C-14-labeled compounds revealed that the herbicides were not bound to any organic material such as cell walls or membranes. Mineralization of the phenyl ring did not occur. None of the microorganisms were able to use the herbicides as the sole carbon source, indicating that biotransformation was a cometabolic process. In some cases, the different biotransformation rates correlated with the lipophilicity of the compounds. Herbicides with high octanol-water partition coefficients were then transformed faster than compounds with a high water solubility. Some microorganisms, however, showed rapid biotransformation of certain, but different, herbicides. This indicates either additional biotransformation pathways or substrate specificities. (C) 1998 Academic Press.
引用
收藏
页码:71 / 82
页数:12
相关论文
共 29 条
[1]   Improved chromatographic method for the simultaneous determination of ten phenylurea herbicides and some of their degradation products in soil [J].
Berger, B .
JOURNAL OF CHROMATOGRAPHY A, 1997, 769 (02) :338-342
[2]  
BERGER B, 1993, P 8 EWRS S BRAUNSCHW, P567
[3]  
BERGER B, 1992, Z PFLKRANKH PFLSCHUT, V13, P397
[4]   ADSORPTION AND TRANSFORMATION OF 4 SUBSTITUTED ANILINES IN SOIL [J].
BOLLAG, JM ;
BLATTMANN, P ;
LAANIO, T .
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY, 1978, 26 (06) :1302-1306
[5]  
BORNER H, 1969, Z PFLANZENK PFLANZEN, V76, P285
[7]  
DEGNER P, 1993, OECD ENV MONOGRAPHS, V67
[8]  
Domsch K.H., 1980, COMPENDIUM SOIL FUNG, P859
[9]  
DOMSCH KH, 1992, PESTIZIDE BODEN MIKR, P575
[10]  
ENGELHARDT G, 1979, CHEMOSPHERE, V10, P725