title: A correlation between the fate and non-extractable residue formation of 14C-metalaxyl and enzymatic activities in soil.
abstract: Extracellular, oxidative soil enzymes like monophenol oxidases and peroxidases play an important role in transformation of xenobiotics and the formation of organic matter in soil. Additionally, these enzymes may be involved in the formation of non-extractable residues (NERs) of xenobiotics during humification processes. To examine this correlation, the fate of the fungicide (14)C metalaxyl in soil samples from Ultuna (Sweden) was studied. Using different soil sterilization techniques, it was possible to differentiate between free, immobilized, and abiotic ("pseudoenzyme"-like) oxidative activities. A correlation between the formation of metalaxyl NER and soil organic matter content, biotic activities, as well as extracellular phenoloxidase and peroxidase activities in the bulk soil and its particle size fractions was determined. Extracellular soil-bound enzymes were involved in NER formation (up to 8% of applied radioactivity after 92 days) of the fungicide independently from the presence of living microbes and different distributions of the NER in the soil humic subfractions.
authors: a Institute for Environmental Research , RWTH Aachen University , Aachen , Germany.
authors: Jens
authors: J
authors: Botterweck
authors: Daniela
authors: D
authors: Claßen
authors: Thordis
authors: T
authors: Zegarski
authors: Christian
authors: C
authors: Gottfroh
authors: Roshni
authors: R
authors: Kalathoor
authors: Andreas
authors: A
authors: Schäffer
authors: Jan
authors: J
authors: Schwarzbauer
authors: Burkhard
authors: B
authors: Schmidt
mesh_terms: D000409:Alanine / Q000031:analogs & derivatives* / Q000378:metabolism; D001673:Biodegradation, Environmental; D002250:Carbon Radioisotopes / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D004784:Environmental Monitoring; D005659:Fungicides, Industrial / Q000378:metabolism*; D008401:Gas Chromatography-Mass Spectrometry; D006812:Humic Substances / Q000032:analysis / Q000382:microbiology; D014442:Monophenol Monooxygenase / Q000378:metabolism; D009195:Peroxidase / Q000378:metabolism; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000378:metabolism*; D013548:Sweden; D013997:Time Factors
chemical_list: D002250:Carbon Radioisotopes; D005659:Fungicides, Industrial; D006812:Humic Substances; D012989:Soil Pollutants; C028175:metalaxyl; D009195:Peroxidase; D014442:Monophenol Monooxygenase; D000409:Alanine