Metabolism of Pyrithiobac Sodium in Soils and Sediment, Addressing Bound Residues via Kinetics Modeling

详细信息    查看全文

• 作者：Ashok K. Sharma ; Lian Wen ; Larry R. Hall ; John G. Allan ; Brett J. Clark
• 刊名：Journal of Agricultural and Food Chemistry
• 出版年：2016
• 出版时间：July 27, 2016
• 年：2016
• 卷：64
• 期：29
• 页码：5793-5802
• 全文大小：718K
• 年卷期：0
• ISSN：1520-5118

文摘

Degradation of pyrithiobac sodium (PE350) was examined in a number of soils and sediments using ¹⁴C-PE350. It degrades primarily via microbial degradation which leads to the separation of the two rings of the molecule. Identification of several metabolites, many of which were minor products, helped to understand the formation of nonextractable residues (NER) and ¹⁴CO₂. In all studies, unextractable residues accounted for a large portion (20–60%) of the residues. Traditional kinetics modeling treats NER and CO₂ as a single compartment, stated as sink, and formation mechanism of such components individually is ignored. Since studies conducted with radiolabeled test substance provides an accurate measurement of NER and CO₂, we have demonstrated that kinetics modeling with these compartments separately can be used to clarify degradation pathways, including the origin of NER and CO₂. This work demonstrated that overall metabolism in soils and sediments proceeded via similar pathways, and kinetics modeling was useful in clarifying the degradation route and formation of NER in all studies.