Influence of microbial and enzymatic activities on immobilisation of xenobiotics in soil organo-clay complexes

微生物和酶活性对土壤有机粘土复合物中外源物质固定的影响

• 批准号: 40956283
• 负责人: Professor Dr. Jan Schwarzbauer
• 金额: --
• 依托单位: Lehrstuhl für Organische Biogeochemie in Geo-Systemen (OBG)
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2007
• 资助国家: 德国
• 起止时间: 2006-12-31 至 2013-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/40956283?language=en
• 关键词: Influence; microbial; enzymatic; activities; immobilisation

Organo-clay complexes are a major sink of non-extractable residues in soil. Although it is known that this incorporation is dominantly assisted by microbial activity, the exact mechanism remains unclear. The competition of extracellular enzyme activity versus contribution of living biomass is under discussion. Therefore we will study the role and participation of microorganisms as well as stabilized extracellular enzymes in the covalent immobilization process of two xenobiotics on organo-clay particles in soil, i.e. the endocrine disrupting compound 353-nonylphenol (p-353-NP) and the fungicide metalaxyl.Three systems are investigated: (a) whole soil, (b) native organo-clay complexes and (c) model organo-clay complexes, both in sterilized and non-sterilized form. This strategy will allow the separation of effects from living micororganisms from those of extracellular enzymes and enables the detailed characterisation of microbial assisted bonding processes. NER formation will be followed by radioanalyses using 14C-xenobiotics and quantitative, enantioselective as well as compound specific isotope analyses using unlabelled substances. Further on the potential of specific enzymes (peroxidase, phenoloxidase) for NER formation will be tested.We will thus test the hypothesis that extracellular enzyme activities are the main driving force for covalent immobilization of xenobiotics to organo-clay complexes in soils.

有机粘土复合物是土壤中不可提取残基的主要水槽。尽管众所周知，这种掺入主要由微生物活性提供帮助，但确切的机制尚不清楚。讨论了细胞外酶活性与活物质贡献的竞争。因此，我们将研究微生物的作用和参与以及稳定的细胞外酶在土壤中两种异种生物学上的两种异种生物学的共价固定过程中有机粘合络合物和（C）模拟有机粘合络合物，均以消毒和非杀菌形式。该策略将允许活生生生物与细胞外酶的作用分离，并实现微生物辅助键合过程的详细表征。 NER形成将使用14C-二培养基，并使用未标记物质进行定量，对映选择性以及复合特定的同位素分析。进一步将测试特异性酶（过氧化物酶，苯酚氧化酶）的潜力。因此，我们将检验以下假设：细胞外酶活性是将异种生物固定在土壤中有机体粘土复合物共价固定的主要驱动力。