Enhanced atrazine degradation in the Fe(III)/peroxymonosulfate system via accelerating Fe(II) regeneration by benzoquinone

To show that an adsorbing biofilm carrier (GAC) can be advantageous for atrazine bioremediation over a non-adsorbing carrier, fluidized bed (FB) reactors were operated under atrazine limiting concentrations using Pseudomonas sp. strain ADP as the atrazine degrading bacteria. The following interrelated subjects were investigated: 1) atrazine adsorption to GAC under conditions of atrazine partial penetration in the biofilm, 2) differences in atrazine degradation rates and 3) stability of atrazine biodegradation under non-sterile anoxic conditions in the GAC reactor versus a reactor with a non-adsorbing biofilm carrier. Results from batch adsorption tests together with modeling best described the biofilm as patchy in nature with covered and non-biofilm covered areas. Under conditions of atrazine partial penetration in the biofilm, atrazine adsorption occurs in the non-covered areas and is consequently desorbed at the base of the biofilm substantially increasing the active biofilm surface area. The double flux of atrazine to the biofilm in the GAC reactor results in lower effluent atrazine concentrations as compared to a FB reactor with a non-adsorbing carrier. Moreover, under non-sterile denitrification conditions, atrazine degradation stability was found to be much higher (several months) using GAC as a biofilm carrier while non-adsorbing carrier reactors showed sharp deterioration within 30 days due to contamination of non-atrazine degrading bacteria.

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Influence of Cd on atrazine degradation and the formation of three primary metabolites in water under the combined pollution

Environmental Science and Pollution Research ◽

10.1007/s11356-020-11819-4 ◽

2020 ◽

Author(s):

Dongyu Xie ◽

Chuansheng Chen ◽

Cui Li ◽

Qinghai Wang

Keyword(s):

Combined Pollution ◽

Primary Metabolites ◽

Atrazine Degradation

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Nitrogen Control of Atrazine Utilization in Pseudomonas sp. Strain ADP

Applied and Environmental Microbiology ◽

10.1128/aem.69.12.6987-6993.2003 ◽

2003 ◽

Vol 69 (12) ◽

pp. 6987-6993 ◽

Cited By ~ 56

Author(s):

Vicente García-González ◽

Fernando Govantes ◽

Liz J. Shaw ◽

Richard G. Burns ◽

Eduardo Santero

Keyword(s):

Wild Type Strain ◽

Nitrogen Sources ◽

Degradation Pathway ◽

Strong Impact ◽

Soil Microcosms ◽

Degradation Rates ◽

Herbicide Atrazine ◽

Mutant Derivative ◽

Nitrogen Repression ◽

Atrazine Degradation

ABSTRACT Pseudomonas sp. strain ADP uses the herbicide atrazine as the sole nitrogen source. We have devised a simple atrazine degradation assay to determine the effect of other nitrogen sources on the atrazine degradation pathway. The atrazine degradation rate was greatly decreased in cells grown on nitrogen sources that support rapid growth of Pseudomonas sp. strain ADP compared to cells cultivated on growth-limiting nitrogen sources. The presence of atrazine in addition to the nitrogen sources did not stimulate degradation. High degradation rates obtained in the presence of ammonium plus the glutamine synthetase inhibitor MSX and also with an Nas− mutant derivative grown on nitrate suggest that nitrogen regulation operates by sensing intracellular levels of some key nitrogen-containing metabolite. Nitrate amendment in soil microcosms resulted in decreased atrazine mineralization by the wild-type strain but not by the Nas− mutant. This suggests that, although nitrogen repression of the atrazine catabolic pathway may have a strong impact on atrazine biodegradation in nitrogen-fertilized soils, the use of selected mutant variants may contribute to overcoming this limitation.

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Atrazine degradation patterns: the role of straw cover and herbicide application history

Scientia Agricola ◽

10.1590/1678-992x-2017-0230 ◽

2019 ◽

Vol 76 (1) ◽

pp. 63-71 ◽

Cited By ~ 1

Author(s):

Daniela Piaz Barbosa Leal ◽

Deborah Pinheiro Dick ◽

Anna Meike Stahl ◽

Stephan Köppchen ◽

Peter Burauel

Keyword(s):

Herbicide Application ◽

Atrazine Degradation

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Identification of a Suitable Solid Carrier as a Matrix for the Permeable Reactive Barrier of Laboratory Scale Model Aquifer for Atrazine Degradation

Tribhuvan University Journal ◽

10.3126/tuj.v25i1.3754 ◽

1970 ◽

Vol 25 (1) ◽

pp. 119-128 ◽

Cited By ~ 1

Author(s):

Binita K Shrestha ◽

Pawan Raj Shakya ◽

MIM Soares

Keyword(s):

Laboratory Scale ◽

Permeable Reactive Barrier ◽

Scale Model ◽

Pseudomonas Sp ◽

Reactive Barrier ◽

Solid Carrier ◽

Different Types ◽

Simultaneous Loss ◽

Static Conditions ◽

Atrazine Degradation

Three different types of physical substrata such as sand, granualar activated carbon (GAC) and plastic macaroni beads were selected to identify a suitable solid carrier as a course matrix for the permeable reactive barrier (PRB) in a sand filled two-dimensional laboratory-scale model aquifer. An adhesion experiment was performed and tested with Pseudomonas sp ADP (PASP) under agitated as well as static conditions. In static conditions, adhesion to GAC was the highest (80%) followed by that to beads (60%). No adhesion to sand was observed under static or agitated conditions. Since atrazine is adsorbed by GAC, its bioavailability for degradation by PADP may be affected. To test this, simultaneous loss of atrazine and release of chloride (dechlorination, the first step in the pathway of atrazine degradation by PADP) were determined in the presence and absence of GAC. Although cells remained viable, no significant chloride release was detected. Thus, plastic macaroni beads were identified and selected as the most suitable support for PADP in the biological permeable reactive barrier (BPRB) of the model aquifer.Key words: Suitable Solid; Laboratory Scale; PADPTribhuvan University JournalVol. XXV, No. 1, 2005Page:119-128Uploaded date: 26, September, 2010

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Contribution of ethylamine degrading bacteria to atrazine degradation in soils

FEMS Microbiology Ecology ◽

10.1111/j.1574-6941.2006.00168.x ◽

2006 ◽

Vol 58 (2) ◽

pp. 271-277 ◽

Cited By ~ 10

Author(s):

Daniel Smith ◽

David E. Crowley

Keyword(s):

Degrading Bacteria ◽

Atrazine Degradation

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Disappearance ofs-Triazines as Affected by Soil pH Using a Balance-Sheet Approach

Weed Science ◽

10.1017/s0043174500037462 ◽

1974 ◽

Vol 22 (4) ◽

pp. 364-373 ◽

Cited By ~ 74

Author(s):

J. A. Best ◽

J. B. Weber

Keyword(s):

Soil Ph ◽

Plant Uptake ◽

Balance Sheet ◽

Integrated System ◽

Alkaline Soil ◽

Silt Loam ◽

Initial Amount ◽

Loam Soil ◽

Microbial Action ◽

Atrazine Degradation

The effect of soil pH on the disappearance of14C ring-labeled atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine], hydroxyatrazine [2-hydroxy-4-(ethylamino)-6-(isopropylamino)-s-triazine], and prometryne [2,4-bis(isopropylamino)-6-(methylthio)-s-triazine] were studied over a 5-month period in a Bladen silt loam soil under greenhouse conditions. Employment of an integrated system allowed simultaneous monitoring of degradation, volatilization, respiration, plant uptake, and leaching processes. A resulting balance-sheet indicated that a range of 87 to 99% of the14C added could be accounted for after 5 months. Degradation was found to be the primary mode of dissipation. The pattern of atrazine degradation was characteristic of nonbiological processes, while prometryne degradation was probably by microbial action. Hydroxyatrazine was the major metabolite from the atrazine treatments while prometryne yielded an unknown and hydroxypropazine [2-hydroxy-4,6-bis(isopropylamino)-s-triazine]. Ex-tractable atrazine after 5 months amounted to 35% of the initial amount added in the pH 7.5 soil and 11% in the pH 5.5 soil, while prometryne occurred as 10% in the pH 7.5 soil and 42% in the pH 5.5 soil. Plant uptake and leaching occurred to a greater extent in the more alkaline soil with each chemical, but these pathways along with volatilization and respiration were minor contributors toward the disappearance of these herbicides.

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Microbial Community and Atrazine-Degrading Genetic Potential in Deep Zones of a Hypersaline Lake-Aquifer System

Applied Sciences ◽

10.3390/app10207111 ◽

2020 ◽

Vol 10 (20) ◽

pp. 7111

Author(s):

Yolanda Espín ◽

Giuliana Aranzulla ◽

Manuel Álvarez-Ortí ◽

Juan José Gómez-Alday

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

16S Rrna Gene Sequencing ◽

Unconfined Aquifer ◽

Hypersaline Lake ◽

Rrna Gene ◽

Deep Aquifer ◽

Aquifer System ◽

Genetic Potential ◽

Atrazine Degradation

The chemical composition of groundwater and related surface water ecosystems can be modified by intensive agricultural activities. This is the case of the Natural Reserve of Pétrola saline lake (Albacete, SE Spain), which constitutes the discharge area of an unconfined aquifer. The extended use of fertilizers and pesticides poses a threat to ecosystem sustainability. One of the most applied herbicides worldwide has been atrazine. Despite being prohibited in Spain since 2007 by European regulations, atrazine can still be detected due to its high persistence in the environment. Atrazine degradation pathways are mediated by biological processes performed by microorganisms with adapted metabolic mechanisms that make in situ bioremediation possible. To evaluate the presence of such microorganisms in the unconfined aquifer, groundwater was collected from a flowing 37.9 m deep piezometer. DNA was extracted, and the bacterial 16S rRNA gene was amplified and cloned. Later, 93 clones were sequenced, providing the first molecular assessment of bacterial community structure in the deep zones of the aquifer. Some of these bacteria have been previously described to be involved in atrazine degradation. In addition, 14 bacteria were isolated from the groundwater samples and identified by 16S rRNA gene sequencing. DNA from these bacteria was subjected to PCR assays with primers designed for the genes involved in the atrazine degradation pathway. Positive results in the amplification were found in at least three of these bacteria (Arthrobacter sp., Nocardioides sp. and Pseudomonas sp.). The atrazine-degrading genetic potential was shown to be dependent on the trzN and atzA,B,C gene combination. These results suggest for the first time the adaptation of the bacterial population present in deep aquifer zones to atrazine exposure, even after more than 15 years of its ban in Spain. In addition, this study provides the baseline data about the bacterial communities found in deep aquifer zones from the hypersaline lake-aquifer system.

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