Abstract
Degradation of the phenylurea herbicide isoproturon (3-(4-isopropylphenyl)-1,1-dimethylurea) and several phenylurea and aniline metabolites was studied in agricultural soils previously exposed to isoproturon. The potential for degradation of the demethylated metabolite 3-(4-isopropylphenyl)-1-methylurea in the soils was much higher compared to isoproturon. In the most active soil only 6% of added 14C-labelled isoproturon was mineralised to 14C2 within 20 days while in the same period 45% of added 14C-labelled 3-(4-isopropylphenyl)-1-methylurea was mineralized. This indicates that the initial N-demethylation may be a limiting step in the complete mineralization of isoproturon. Repeated addition of 3-(4-isopropylphenyl)-1-methylurea to the soil and further subculturing in mineral medium led to a highly enriched mixed bacterial culture with the ability to mineralize 3-(4-isopropylphenyl)-1-methylurea.The culture did not degrade either isoproturon or the didemethylatedmetabolite 3-(4-isopropylphenyl)-urea when provided as sole source of carbon and energy. The metabolite 4-isopropyl-aniline was also degraded and utilised for growth, thus indicating that 3-(4-isopropylphenyl)-1-methylurea is degraded byan initial cleavage of the methylurea-group followed by mineralizationof the phenyl-moiety. Several attempts were made to isolate pure bacterial cultures degrading 3-(4-isopropylphenyl)-1-methylurea or 4-isopropyl-aniline,but they were not successful.
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References
Alexander M (1994) Biodegradation and bioremediation. Academic Press, San Diego, California
Beck AJ,Harris GL,Howse KR,Johnston AE andJones KC (1996) Spatial and temporal variation of isoproturon residues and associated sorption/desorption parameters at the field scale. Chemosphere 33: 1283–1295
Berger BM (1998) Parameters influencing Biotransformation rates of phenylurea herbicides by soil microorganisms. Pestic. Biochem. Physiol. 60: 71–82
Cox L,Walker A &Welch SJ (1996) Evidence for the accelerated degradation of isoproturon in soils. Pestic. Sci. 48: 253–260
Cullington JE &Walker A (1999) Rapid biodegradation of diuron and other phenylurea herbicides by a soil bacterium. Soil Biol. Biochem. 31: 677–686
Engelhardt G,Wallnöfer PR &Plapp R (1973) Purification and properties of an aryl acylamidase of Bacillus Sphaericus, catalyzing the hydrolysis of various phenylamide herbicides and fungicides. Appl. Microbiol. 26: 709–718
Forlani G,Mangiagalli A, Nielsen E &Suardi CM (1999) Degradation of the phosphonate herbicide glyphosate in soil: evidence for a possible involvement of unculturable microorganisms. Soil Biol. Biochem. 31: 991–997
Gaillardon P &Sabar M (1994) Changes in the concentration of isoproturon and its degradation products in soil and soil solution during incubation at two temperatures. Weed Res. 34: 243–250
Hobbie JE,Dagley RJ &Jasper S (1977) Use of nucleopore filters for counting bacteria by fluorescence microscopy. Appl. Environ. Microbiol. 33: 1225–1228
Johnson AC,Hughes CD,Williams RJ &Chilton PJ (1998) Potential for aerobic isoproturon biodegradation and sorption in the unsaturated and saturated zones of a chalk aquifer. J. Contam. Hydrol. 30: 281–297
Juhler RK,Sørensen SR &Larsen L (2001) Analysing transformation products of herbicide residues in environmental samples. Water Res. 35: 17–24
Kristensen GB, Sørensen SR & Aamand J (accepted) Mineralization of 2,4-D, mecoprop, isoproturon, and terbuthylazine in a chalk aquifer. Pest Manag. Sci.
Kubiak R,Ellssel H,Lambert M &Eichhorn KW (1995) Degradation of isoproturon in soil in relation to changes of microbial biomass and activity in small-scale laboratory and outdoors studies. Intern. J. Environ. Anal. Chem. 59: 123–132
Kulshrestha G &Mukerjee SK (1986) The photochemical decomposition of the herbicide isoproturon. Pestic. Sci. 17: 489–494
Kulshrestha G (1983) Persistence of the herbicide isoproturon in soil. Asp. Appl. Biol. 4: 413–422
Larsen L,Sørensen SR &Aamand J (2000) Mecoprop, atrazine and isoproturon in a sandy aquifer: Vertical distribution of mineralization potential. Environ. Sci. Technol. 34: 2426–2430
Lehr S,Glässgen WE,Sandermann H,Beese Jr. F &Scheunert I (1996) Metabolism of isoproturon in soils originating from different agricultural management systems and in cultures of isolated bacteria. Intern. J. Environ. Anal. Chem. 65: 231–344
Mansour M,Feicht EA,Behechti A,Schramm KW &Kettrup A (1999) Determination photostability of selected agrochemicals in water and soil. Chemosphere 39: 575–585
Mudd PJ,Hance RJ &Wright SJL (1983) The persistence and metabolism of isoproturon in soil. Weed Res. 23: 239–347
Nitchke L &Schussler W (1998) Surface water pollution by herbicides from effluents of waste water treatment plants. Chemosphere 36: 35–41
Pieuchot M,Perrin-Ganier C,Portal J-M &Schiavon M (1996) Study on the mineralization and degradation of isoproturon in three soils. Chemosphere 33: 467–478
Remde A &Traunspurger W (1994) A method to assess the toxicity of pollutants on anaerobic microbial degradation activity in sediments. Environ. Toxicol. Wat. Qual. 9: 293–298
Reuter S,Ilim M,Munch JC,Andreux F &Scheunert I (1999) A model for the formation and degradation of bound residues of the herbicide 14C-isoproturon in soil. Chemosphere 39: 627–639
Ridgway HF,Safarik J,Phipps D,Carl P &Clark D (1990) Identi-fication and catabolic activity of well-derived gasoline-degrading bacteria from a contaminated aquifer. Appl. Environ. Microbiol. 56: 3565–3575
Roberts SJ,Walker A,Cox L &Welch SJ (1998) Isolation of isoproturon-degrading bacteria from treated soil via three different routes. J. App. Microbiol. 85: 309–316
Roberts SJ,Walker A,Parekh NR,Welch SJ &Waddington MJ (1993) Studies on a mixed bacterial culture from soil which degrades the herbicide linuron. Pestic. Sci. 39: 71–78
Schuelein J,Glaessgen WE,Hertkorn N,Schroeder P,Sandermann H Jr. &Kettrup A. (1996) Detection and identification of the herbicide isoproturon and its metabolites in field samples after a heavy rainfall event. Intern. J. Environ. Anal. Chem. 65: 193–202
Spliid HS &Køppen B (1998) Occurrence of pesticides in Danish shallow ground water. Chemosphere 37: 1307–1316
Torsvik V,Goksøyr J &Daae FL (1990) High diversity in DNA of soil bacteria. Appl. Environ. Microbiol. 56: 782–787
Walker A,Jurado-Exposito M,Bending GD andSmith VJR (2001) Spatial variability in the degradation rate of isoproturon in soil. Environ. Poll. 111: 407–415
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Sørensen, S.R., Aamand, J. Biodegradation of the Phenylurea Herbicide Isoproturon and its Metabolites in Agricultural Soils. Biodegradation 12, 69–77 (2001). https://doi.org/10.1023/A:1011902012131
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DOI: https://doi.org/10.1023/A:1011902012131