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Xu D, Ji Y, Du B, He B, Chen H, Sun H, Yin X. The synergistic effect of typical chiral organic acids and solution chemistry conditions on the transport of 2-arylpropionic acid chiral derivatives in porous media. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 351:124059. [PMID: 38703979 DOI: 10.1016/j.envpol.2024.124059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 03/27/2024] [Accepted: 04/25/2024] [Indexed: 05/06/2024]
Abstract
The hazards of man-made chiral compounds are of great public concern, with reports of worrying stereoselective compounds and an urgent need to assess their transport. This study evaluated the transport of 2-arylpropionic acid derivatives enantiomers (2-APA) in porous media under a variety of solution chemistry conditions via column packing assays. The results revealed the introduction of Malic acid (MA) enantiomers enhanced the mobility of 2-APA enantiomers, but the enhancement effect was different for different 2-APA enantiomers. Batch sorption experiments confirmed that the MA enantiomers occupied the sorption site of the quartz sand, thus reducing the deposition of the 2-APA enantiomer. Homo- or heterochirality between 2-APA and MA dominates the transport of 2-APA enantiomers, with homochirality between them triggering stronger retention and vice versa. Further evaluating the effect of solution chemistry conditions on the transport of 2-APA enantiomers, increased ionic strength attenuated the mobility of 2-APA enantiomers, whereas introduced coexisting cations enhanced the retention of 2-APA enantiomers in the column. The redundancy analyses corroborated these solution chemistry conditions were negatively correlated with the transport of 2-APA enantiomers. The coupling of pH and these conditions reveals electrostatic forces dominate the transport behavior and stereoselective interactions of 2-APA enantiomers. Distinguishing the transport of enantiomeric pair helps to understand the difference in stereoselectivity of enantiomers and promises to remove the more hazardous one.
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Affiliation(s)
- Duo Xu
- College of Natural Resources and Environment, Northwest A & F University, Yangling, Shaanxi, 712100, PR China
| | - Yantian Ji
- College of Natural Resources and Environment, Northwest A & F University, Yangling, Shaanxi, 712100, PR China
| | - Bowen Du
- College of Natural Resources and Environment, Northwest A & F University, Yangling, Shaanxi, 712100, PR China
| | - Bo He
- College of Natural Resources and Environment, Northwest A & F University, Yangling, Shaanxi, 712100, PR China
| | - Hongyang Chen
- College of Natural Resources and Environment, Northwest A & F University, Yangling, Shaanxi, 712100, PR China
| | - Huimin Sun
- College of Natural Resources and Environment, Northwest A & F University, Yangling, Shaanxi, 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture and Rural Affairs, Yangling, Shaanxi, 712100, PR China
| | - Xianqiang Yin
- College of Natural Resources and Environment, Northwest A & F University, Yangling, Shaanxi, 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture and Rural Affairs, Yangling, Shaanxi, 712100, PR China.
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2
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Facenda G, Celis R, Gámiz B, López-Cabeza R. An enantioselective study of the behavior of the herbicide ethofumesate in agricultural soils: Impact of the addition of organoclays and biochar. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 270:115870. [PMID: 38159340 DOI: 10.1016/j.ecoenv.2023.115870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 12/15/2023] [Accepted: 12/19/2023] [Indexed: 01/03/2024]
Abstract
Chiral pesticides that are still commercialized and incorporated into the environment as racemic mixtures of enantiomers require evaluation of the enantioselectivity of their biological activity and environmental fate processes for a better prediction of their field efficacy and environmental risks. In this work, we successfully separated the enantiomers of the chiral herbicide ethofumesate (ETFM), determined their absolute configuration, and characterized their herbicidal activity as well as their adsorption, degradation, enantiomerization, and leaching in Mediterranean agricultural soils. While the herbicidal activity of R-ethofumesate to the sensitive species Portulaca grandiflora was greater than that of S-ethofumesate, the adsorption, degradation, and leaching of the herbicide showed negligible enantioselectivity and enantiomer interconversion did not occur in soils. The adsorption of both enantiomers showed a positive correlation with the soil organic carbon content (r = 0.856, P = 0.015), and their degradation in soils occurred slowly (DT50 > 60 days) and at similar rates independent of their application as individual enantiomers or as a racemic mixture of enantiomers. The addition of three highly adsorptive materials to a scarcely adsorptive soil increased the adsorption of the enantiomers of ETFM and delayed their degradation without affecting the non-enantioselective character of the processes. As a result of their high adsorption capacity, the materials were highly effective in reducing the leaching of both enantiomers of ETFM through soil columns. The results of this work indicate that the application of single-enantiomer ETFM formulations, based on a higher herbicidal activity or a lower toxicity to non-target organisms of the formulated enantiomer, would reduce considerable exposure risks associated with incorporating into the environment the less favorable enantiomer, as this would show long persistence and high leaching potential in soils similar to its optical isomer.
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Affiliation(s)
- Gracia Facenda
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, 41012 Sevilla, Spain
| | - Rafael Celis
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, 41012 Sevilla, Spain
| | - Beatriz Gámiz
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, 41012 Sevilla, Spain; Departamento de Química Inorgánica, Instituto de Química para la Energía y Medioambiente (IQUEMA), Universidad de Córdoba, Campus de Rabanales, 14014 Córdoba, Spain
| | - Rocío López-Cabeza
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, 41012 Sevilla, Spain.
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Siedt M, Vonhoegen D, Smith KEC, Roß-Nickoll M, van Dongen JT, Schäffer A. Fermented biochar has a markedly different effect on fate of pesticides in soil than compost, straw, and a mixed biochar-product. CHEMOSPHERE 2023; 344:140298. [PMID: 37758091 DOI: 10.1016/j.chemosphere.2023.140298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 05/31/2023] [Accepted: 09/25/2023] [Indexed: 10/03/2023]
Abstract
Current knowledge about how biochars affect the fate of pesticides in soil is based on studies that used pure biochars. After finding that an additional biological post-pyrolysis treatment, such as co-composting or lactic fermentation, is required for biochars for superior performance in temperate arable soils, a knowledge gap formed of how such further processed biochar products would affect the fate of pesticides in soil. This study compared the effects of a novel fermented biochar alone or mixed with biogas residues on the fate of two pesticides, 4-chloro-2-methylphenoxyacetic acid (MCPA) and metalaxyl-M, in a temperate arable soil to the traditional organic amendments wheat straw and compost. The fate of 14C-labeled MCPA was markedly affected in different ways. Fermented biochar effectively reduced the water-extractability and mineralization due to adsorption that was comparable to adsorption strengths reported for pure biochars. However, this effect was weak for the biochar mixed with biogas residues. Straw reduced water-extractable amounts due to increased biodegradation and formation of likely biogenic non-extractable residues of MCPA. In contrast, compost decelerated mineralization and increased the water solubility of the MCPA residues due to released dissolved organic matter. The amendments' effects were minor regarding 14C-metalaxyl-M, except for the fermented biochar which again reduced water-extractability and delayed degradation due to adsorption. Thus, the effects of the organic amendments differed for the two pesticide compounds with only the fermented biochar's effect being similar for both. However, this effect was no longer present in the mixed product containing 20% biochar. Our findings clearly show that biologically treated biochar-containing products can affect the fate of pesticides in soil very differently, also when compared to traditional organic amendments. Such impacts and their desirable and undesirable ecotoxicological implications need to be considered before the large-scale application of biochars to temperate arable soils.
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Affiliation(s)
- Martin Siedt
- Institute for Environmental Research, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany; Molecular Ecology of the Rhizosphere, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany.
| | - Denise Vonhoegen
- Institute for Environmental Research, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Kilian E C Smith
- Institute for Environmental Research, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Martina Roß-Nickoll
- Institute for Environmental Research, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Joost T van Dongen
- Molecular Ecology of the Rhizosphere, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
| | - Andreas Schäffer
- Institute for Environmental Research, RWTH Aachen University, Worringerweg 1, 52074, Aachen, Germany
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Galán-Pérez JA, Gámiz B, Pavlovic I, Celis R. Enantiomer-Selective Characterization of the Adsorption, Dissipation, and Phytotoxicity of the Plant Monoterpene Pulegone in Soils. PLANTS 2022; 11:plants11101296. [PMID: 35631720 PMCID: PMC9143748 DOI: 10.3390/plants11101296] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 05/10/2022] [Accepted: 05/10/2022] [Indexed: 11/16/2022]
Abstract
Plant monoterpenes have received attention for their ecological functions and as potential surrogates for synthetic herbicides, but very little is known about the processes that govern their behavior in the soil environment, and even less about the possible enantioselectivity in the functions and environmental behavior of chiral monoterpenes. We characterized the adsorption and dissipation of the two enantiomers of the chiral monoterpene pulegone in different soils, and their phytotoxicity to different plant species through Petri dish and soil bioassays. R- and S-pulegone displayed a low-to-moderate non-enantioselective adsorption on the soils that involved weak interaction mechanisms. Soil incubation experiments indicated that, once in the soil, R- and S-pulegone are expected to suffer rapid volatilization and scarcely enantioselective, biodegradation losses. In Petri dishes, the phytotoxicity of pulegone and its enantioselectivity to Lactuca sativa, Hordeum vulgare, and Eruca sativa was species-dependent. Lactuca sativa was the most sensitive species and showed higher susceptibility to S- than to R-pulegone. Biodegradation and volatilization losses greatly reduced the phytotoxic activity of S-pulegone applied to soil, but the addition of a highly-adsorptive organoclay stabilized the monoterpene and increased its phytotoxic effect. Stabilization by adsorption may represent an important mechanism by which the bioactivity of plant monoterpenes in soils can be increased.
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Affiliation(s)
- Jose Antonio Galán-Pérez
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), Consejo Superior de Investigaciones Científicas (CSIC), Avenida Reina Mercedes 10, 41012 Sevilla, Spain; (J.A.G.-P.); (R.C.)
| | - Beatriz Gámiz
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), Consejo Superior de Investigaciones Científicas (CSIC), Avenida Reina Mercedes 10, 41012 Sevilla, Spain; (J.A.G.-P.); (R.C.)
- Correspondence: ; Tel.: +34-954-624-711
| | - Ivana Pavlovic
- Departamento de Química Inorgánica, Instituto Universitario de Investigación en Química Fina y Nanoquímica (IUIQFN), Universidad de Córdoba, Campus de Rabanales, 14071 Córdoba, Spain;
| | - Rafael Celis
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), Consejo Superior de Investigaciones Científicas (CSIC), Avenida Reina Mercedes 10, 41012 Sevilla, Spain; (J.A.G.-P.); (R.C.)
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5
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Xu S, Shen F, Song J, Wang Y, Yu S, Zhang L, Fang H, Yu Y. Enantioselectivity of new chiral triazole fungicide mefentrifluconazole: Bioactivity against phytopathogen, and acute toxicity and bioaccumulation in earthworm (Eisenia fetida). THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 815:152937. [PMID: 35007570 DOI: 10.1016/j.scitotenv.2022.152937] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 12/31/2021] [Accepted: 01/02/2022] [Indexed: 06/14/2023]
Abstract
Elaborating the environmental behavior of mefentrifluconazole, a novel triazole fungicide, in stereoselective level is of paramount importance for the application of the pesticide in agriculture. In this study, the enantioselective bioactivity, acute toxicity and stereoselective bioaccumulation of mefentrifluconazole in earthworm (Eisenia fetida) were investigated. Bioactivity tests against four pathogens revealed that R-(-)-mefentrifluconazole exhibited approximately 11-113 times higher bioactivity than its S-(+)-mefentrifluconazole. However, the LC50 of S-(+)-, rac- and R-(-)-mefentrifluconazole to earthworm was measured to be 4.1, 11.4 and 7.3 μg/cm2, respectively, indicating active ingredient R-(-)-mefentrifluconazole is less toxic than its racemate and S-form. Accumulation of mefentrifluconazole in earthworms was non-enantioselective and negatively related to its adsorption onto soils. The concentration of mefentrifluconazole in in situ pore water (CIPW) and CaCl2 extraction (CCaCl2) was closely related to its accumulation in earthworms, suggesting that CIPW and CCaCl2 could be appropriate indicators for estimation of the bioavailability of mefentrifluconazole in soil. Conclusively, our study provides necessary information for the risk assessment of mefentrifluconazole in agriculture.
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Affiliation(s)
- Shiji Xu
- Institute of Pesticide and Environmental Toxicology, the Key Laboratory of Molecular Biology of Crop Pathogens and Insects, the Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Fan Shen
- Institute of Pesticide and Environmental Toxicology, the Key Laboratory of Molecular Biology of Crop Pathogens and Insects, the Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Jialu Song
- Institute of Pesticide and Environmental Toxicology, the Key Laboratory of Molecular Biology of Crop Pathogens and Insects, the Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Yingnan Wang
- Institute of Pesticide and Environmental Toxicology, the Key Laboratory of Molecular Biology of Crop Pathogens and Insects, the Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Sumei Yu
- Institute of Pesticide and Environmental Toxicology, the Key Laboratory of Molecular Biology of Crop Pathogens and Insects, the Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Luqing Zhang
- Institute of Pesticide and Environmental Toxicology, the Key Laboratory of Molecular Biology of Crop Pathogens and Insects, the Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China.
| | - Hua Fang
- Institute of Pesticide and Environmental Toxicology, the Key Laboratory of Molecular Biology of Crop Pathogens and Insects, the Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
| | - Yunlong Yu
- Institute of Pesticide and Environmental Toxicology, the Key Laboratory of Molecular Biology of Crop Pathogens and Insects, the Key Laboratory of Biology of Crop Pathogens and Insects of Zhejiang Province, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
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6
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Shen Y, Yao X, Jin S, Yang F. Enantiomer/stereoisomer-specific residues of metalaxyl, napropamide, triticonazole, and metconazole in agricultural soils across China. ENVIRONMENTAL MONITORING AND ASSESSMENT 2021; 193:773. [PMID: 34741224 DOI: 10.1007/s10661-021-09562-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 10/26/2021] [Indexed: 06/13/2023]
Abstract
In this study, the residual status of four chiral pesticides including metalaxyl, napropamide, triticonazole, metconazole, and their enantiomers/stereoisomers were investigated in agricultural soils across China. The levels in the soils were detected as non-detected (n.d.)-16.67 ng/g for metalaxyl with a median of 0.14 ng/g; 0.004-32.99 ng/g for napropamide with a median of 0.29 ng/g; n.d.-207.39 ng/g for triticonazole with a median of 1.29 ng/g; and n.d.-71.83 ng/g for metconazole with a median of 1.03 ng/g, respectively. Enantiomer/stereoisomer-specific residues were observed for metalaxyl and triticonazole. R-Metalaxyl and R-triticonazole were identified as the major enantiomers in the soils for the two pesticides. There was no obvious enantioselective residue for napropamide in most of the soils. As for metconazole, metconazole-1 and metconazole-4 were identified as the major stereoisomers in the soils. These results suggest that enantiomer/stereoisomer-specific risk should be considered when assessing the ecological safety of these pesticides in soils.
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Affiliation(s)
- Yi Shen
- MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, No. 866, Yuhangtang Road, Hangzhou, 310058, China
| | - Xiaoshan Yao
- Key Laboratory of Analytical Chemistry of the State Affairs Commission, College of Chemistry and Materials Science, South-Central University for Nationalities, Wuhan, 430074, China
| | - Shiwei Jin
- Key Laboratory of Analytical Chemistry of the State Affairs Commission, College of Chemistry and Materials Science, South-Central University for Nationalities, Wuhan, 430074, China
| | - Fangxing Yang
- MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, No. 866, Yuhangtang Road, Hangzhou, 310058, China.
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Debnath MK, Oyama W, Ono Y, Sugimoto T, Watanabe R, Haraguchi N. Synthesis of polymer microsphere‐supported chiral pyrrolidine catalysts by precipitation polymerization and their application to asymmetric Michael addition reactions. JOURNAL OF POLYMER SCIENCE 2021. [DOI: 10.1002/pol.20210128] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Mithun Kumar Debnath
- Department of Applied Chemistry and Life Science, Graduate School of Engineering Toyohashi University of Technology Toyohashi Japan
| | - Wako Oyama
- Department of Applied Chemistry and Life Science, Graduate School of Engineering Toyohashi University of Technology Toyohashi Japan
| | - Yuya Ono
- Department of Applied Chemistry and Life Science, Graduate School of Engineering Toyohashi University of Technology Toyohashi Japan
| | - Takuya Sugimoto
- Department of Applied Chemistry and Life Science, Graduate School of Engineering Toyohashi University of Technology Toyohashi Japan
| | - Rina Watanabe
- Department of Applied Chemistry and Life Science, Graduate School of Engineering Toyohashi University of Technology Toyohashi Japan
| | - Naoki Haraguchi
- Department of Applied Chemistry and Life Science, Graduate School of Engineering Toyohashi University of Technology Toyohashi Japan
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Simultaneous enantiomeric analysis of five proton-pump inhibitors in soil and sediment using a modified QuEChERS method and chiral high performance liquid chromatography coupled with tandem mass spectrometry. Microchem J 2021. [DOI: 10.1016/j.microc.2020.105625] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Zhou Q, Zhang X, Wu Z. Impact of TiO 2 and ZnO Nanoparticles on Soil Bacteria and the Enantioselective Transformation of Racemic-Metalaxyl in Agricultural Soil with Lolium perenne: A Wild Greenhouse Cultivation. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:11242-11252. [PMID: 32936624 DOI: 10.1021/acs.jafc.0c03959] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The effects of TiO2 and ZnO nanoparticles on soil bacteria and enantioselective transformation of racemic-metalaxyl (rac-metalaxyl) in agricultural soil with or without Lolium perenne were investigated in an outdoor greenhouse. After a 70-day exposure to 2‰ ZnO, microbial biomass carbon decreased by 66% and bacterial community composition significantly changed. Meanwhile, ZnO decreased chlorophyll cumulation in L. perenne by 34%. ZnO also inhibited the enantioselective transformation of metalaxyl enantiomers and changed the enantiomer fraction of metalaxyl. TiO2 showed similar effects but to a lesser extent. L. perenne promoted the transformation of rac-metalaxyl and ingested TiO2 and ZnO. L. perenne changed the bacterial co-occurrence networks and biomarkers in native soil and soil exposed to TiO2 and ZnO. L. perenne reduced the inhibition effects of TiO2 and ZnO on the transformation of rac-metalaxyl. The decrease in the relative abundance of soil keystone taxa such as Acidobacteria and Gemmatimonas might respond to the corresponding slow transformation of rac-metalaxyl in soils exposed to TiO2 and ZnO, regardless of L. perenne. Our results demonstrated the existence of mutual interactions among the impact of engineered nanoparticles on different components (microbes, plants, and coexisting pollutants) in the terrestrial ecosystem.
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Affiliation(s)
- Qing Zhou
- School of Resources and Environmental Science, Wuhan University, Wuhan 430079, China
| | - Xu Zhang
- School of Resources and Environmental Science, Wuhan University, Wuhan 430079, China
| | - Zhong Wu
- Hubei Jingzhou Environmental Protection Science and Technology Co., Ltd, Jingzhou 434000, China
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Cutillas V, García-Valverde M, Gómez-Ramos MDM, Díaz-Galiano FJ, Ferrer C, Fernández-Alba AR. Supercritical fluid chromatography separation of chiral pesticides: Unique capabilities to study cyhalothrin and metalaxyl as examples. J Chromatogr A 2020; 1620:461007. [DOI: 10.1016/j.chroma.2020.461007] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 02/28/2020] [Accepted: 03/02/2020] [Indexed: 12/24/2022]
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11
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Sanganyado E, Lu Z, Liu W. Application of enantiomeric fractions in environmental forensics: Uncertainties and inconsistencies. ENVIRONMENTAL RESEARCH 2020; 184:109354. [PMID: 32182482 DOI: 10.1016/j.envres.2020.109354] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 03/01/2020] [Accepted: 03/04/2020] [Indexed: 05/27/2023]
Abstract
The assumption that only biological processes are enantioselective introduces challenges in the reliability of enantioselective analysis as a tool for discriminating biotic and abiotic processes in the environmental fate of chiral pollutants. Enantioselectivity does not depend on the nature of the fate process a chiral contaminant undergoes but on the interaction of the chiral contaminant with homochirality inducing external agents (e.g. chiral molecules, macromolecules or surfaces such as enzymes, blood plasma, proteins, chiral co-pollutants, humic acid and soil organominerals). The environmental behavior of a chiral contaminant is difficult to anticipate because the interactions between the chiral contaminants and the homochirality inducing external agents is often complex and strongly influenced by local environment conditions such as pH, redox conditions, organic carbon, organic nitrogen, humic acid, and redox conditions. Furthermore, the use of enantioselective analysis in environmental forensics depend on the adequate separation and accurate identification and quantification of the enantiomers of the chiral contaminant. Matrix effects, instrument effects, inadequate enantioselective separation, and poor quantification techniques introduce uncertainties in the determination of enantiomeric composition. Here we present the weaknesses of this assumption and recommend using enantiomeric fractions as chemical markers of biotransformation with caution. We recommend using stable isotopes, including abiotic controls to determine if enantioselective sorption occurs, and determining stability of enantiomers in solvent or at elevated temperatures to account for confounding factors arising from matrix effects, enantioselective abiotic processes, and enantiomerization due solvent and thermal lability of the chiral analyte, respectively to maintain the integrity of the utility of enantiomeric composition changes as an environmental forensics tool.
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Affiliation(s)
- Edmond Sanganyado
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou, Guangdong, 515063, China
| | - Zhijiang Lu
- College of Environmental and Resource Sciences, Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Zhejiang University, Hangzhou, Zhejiang, 310058, China
| | - Wenhua Liu
- Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou, Guangdong, 515063, China.
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12
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Detection, identification and determination of chiral pharmaceutical residues in wastewater: Problems and challenges. Trends Analyt Chem 2020. [DOI: 10.1016/j.trac.2019.115710] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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13
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You X, Zheng H, Ge J, Fang S, Suo F, Kong Q, Zhao P, Zhang G, Zhang C, Li Y. Effect of Biochar on the Enantioselective Soil Dissipation and Lettuce Uptake and Translocation of the Chiral Pesticide Metalaxyl in Contaminated Soil. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:13550-13557. [PMID: 31721576 DOI: 10.1021/acs.jafc.9b05559] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Enantioselectivity is usually ignored when assessing potential biochar-based methods of redressing pesticide contamination of soils. In this study, the effect of woodchip biochar (WBC) on the enantioselective dissipation of metalaxyl in soil and its uptake and translocation by lettuce were investigated. S-metalaxyl (T1/2 = 29.8 days) dissipated more quickly than R-metalaxyl (T1/2 = 36.4 days) in unamended soil. The addition of WBC to the soil decreased the dissipation rate and the enantioselectivity of metalaxyl. Metalaxyl distribution showed opposing enantioselectivity in lettuce, with roots and shoots showing preferences for R-metalaxyl and S-metalaxyl, respectively. Enrichment with WBC decreased the concentrations of metalaxyl and metalaxyl acid enantiomers in lettuce and reduced the ability of the shoots to transport the highly toxic R-metalaxyl from roots. This is the first study to provide evidence that amending soil with biochar affects the enantioselective uptake and translocation of a chiral pesticide.
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Affiliation(s)
- Xiangwei You
- Marine Agriculture Research Center, Tobacco Research Institute , Chinese Academy of Agricultural Sciences , Qingdao 266101 , China
| | - Hao Zheng
- Institute of Coastal Environmental Pollution Control, Key Laboratory of Marine Environment and Ecology, Ministry of Education, Institute for Advanced Ocean Study , Ocean University of China , Qingdao 266100 , China
| | - Jing Ge
- Institute of Food Quality and Safety , Jiangsu Academy of Agricultural Sciences , Zhongling Street , Nanjing 210014 , China
| | - Song Fang
- Marine Agriculture Research Center, Tobacco Research Institute , Chinese Academy of Agricultural Sciences , Qingdao 266101 , China
| | - Fengyue Suo
- Marine Agriculture Research Center, Tobacco Research Institute , Chinese Academy of Agricultural Sciences , Qingdao 266101 , China
| | - Qingxian Kong
- Marine Agriculture Research Center, Tobacco Research Institute , Chinese Academy of Agricultural Sciences , Qingdao 266101 , China
| | - Peng Zhao
- Marine Agriculture Research Center, Tobacco Research Institute , Chinese Academy of Agricultural Sciences , Qingdao 266101 , China
| | - Guangyu Zhang
- Marine Agriculture Research Center, Tobacco Research Institute , Chinese Academy of Agricultural Sciences , Qingdao 266101 , China
| | - Chengsheng Zhang
- Marine Agriculture Research Center, Tobacco Research Institute , Chinese Academy of Agricultural Sciences , Qingdao 266101 , China
| | - Yiqiang Li
- Marine Agriculture Research Center, Tobacco Research Institute , Chinese Academy of Agricultural Sciences , Qingdao 266101 , China
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14
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Feng J, Dou J, Wu Z, Yin D, Wu W. Controlled Release of Biological Control Agents for Preventing Aflatoxin Contamination from Starch⁻Alginate Beads. Molecules 2019; 24:E1858. [PMID: 31091816 PMCID: PMC6572238 DOI: 10.3390/molecules24101858] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 05/02/2019] [Accepted: 05/07/2019] [Indexed: 11/30/2022] Open
Abstract
For the wise use of fungal biocontrol and metalaxyl fungicide, starch-alginate-based formulations have been developed by encapsulating metalaxyl and non-toxigenic Aspergillus flavus spores simultaneously in the form of microspheres using calcium chloride as a cross-linking agent. The formulations were characterized by Fourier transform infrared spectroscopy (FTIR), a scanning electron micrograph (SEM), and thermogravimetry (TGA). Formulation characteristics, including the bead size, entrapment efficiency, swelling ratio of the beads, and rheological properties, were analyzed. The release behavior of beads with different formulations was evaluated. The addition of kaolin and rice husk powder in starch-alginate beads retarded the release profile of spores and metalaxyl. The release of the active ingredient from starch-alginate-kaolin beads and starch-alginate-rice husk powder beads occurred in both a controlled and sustained manner. Additionally, the release rate decreased with the increase of kaolin or rice husk powder content. The beads added with kaolin were slower than the release of rice husk powder. In comparison, spores released slower and lasted longer than metalaxyl. The starch-alginate-kaolin formulations could be used as controlled release material in the field of biocontrol and reduce the harm of fungicides to the environment.
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Affiliation(s)
- Jiachang Feng
- Department of Biological and Agricultural Engineering, Jilin University, Changchun 130000, China.
| | - Jianpeng Dou
- Department of Biological and Agricultural Engineering, Jilin University, Changchun 130000, China.
| | - Zidan Wu
- Department of Biological and Agricultural Engineering, Jilin University, Changchun 130000, China.
| | - Dongxue Yin
- Department of Biological and Agricultural Engineering, Jilin University, Changchun 130000, China.
| | - Wenfu Wu
- Department of Biological and Agricultural Engineering, Jilin University, Changchun 130000, China.
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15
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Gámiz B, Facenda G, Celis R. Nanoengineered Sorbents To Increase the Persistence of the Allelochemical Carvone in the Rhizosphere. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:589-596. [PMID: 30562019 DOI: 10.1021/acs.jafc.8b05692] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
This study investigates the changes in sorption/desorption, dissipation, and leaching of the two enantiomeric forms of the allelochemical carvone, R-carvone and S-carvone, after amending an agricultural soil sample with two nanoengineered sorbents: biochar (BC) and organoclay (OCl). The sorption of carvone enantiomers was nonenantioselective and similarly improved by the addition of OCl and BC to the soil. However, OCl-amended soil showed reversible sorption, whereas BC-amended soil displayed sorption-desorption hysteresis. Dissipation of carvone enantiomers was enantioselective. Both amendments increased the half-life of the enantiomers in the soil. This effect was more pronounced for BC-amended soil and for S-carvone. Leaching of R- and S-carvone through soil columns was scarce in unamended soil (<7%), due to their rapid degradation during leaching, and null for OCl- and BC-amended soil, for which much of the applied R- and S-carvone remained in the top 0-5 cm of the amended soil layer. Addition of biochars and organoclays could help increase the persistence of carvone enantiomers in the rhizosphere, which may favor their use as residual pest-management substances.
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Affiliation(s)
- Beatriz Gámiz
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC , Avenida Reina Mercedes 10 , 41012 Sevilla , Spain
| | - Gracia Facenda
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC , Avenida Reina Mercedes 10 , 41012 Sevilla , Spain
| | - Rafael Celis
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC , Avenida Reina Mercedes 10 , 41012 Sevilla , Spain
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16
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Yang J, Tan X, Zhao Y. Chiral recognition of the carnitine enantiomers using rhodamine B as a resonance Rayleigh scattering probe. Chirality 2018; 30:1173-1181. [DOI: 10.1002/chir.23004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 04/26/2018] [Accepted: 06/07/2018] [Indexed: 12/30/2022]
Affiliation(s)
- Jidong Yang
- School of Environment and Chemical Engineering; Chongqing Three Gorges University; Chongqing People's Republic of China
- School of Chemistry and Chemical Engineering; Southwest University; Chongqing People's Republic of China
| | - Xuanping Tan
- School of Environment and Chemical Engineering; Chongqing Three Gorges University; Chongqing People's Republic of China
| | - Yanmei Zhao
- School of Environment and Chemical Engineering; Chongqing Three Gorges University; Chongqing People's Republic of China
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17
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Zhang Z, Gao B, Li L, Zhang Q, Xia W, Wang M. Enantioselective degradation and transformation of the chiral fungicide prothioconazole and its chiral metabolite in soils. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 634:875-883. [PMID: 29660882 DOI: 10.1016/j.scitotenv.2018.03.375] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 03/26/2018] [Accepted: 03/30/2018] [Indexed: 06/08/2023]
Abstract
Prothioconazole is a widely used chiral triazole fungicide. In this work, the enantioselective degradation and transformation of prothioconazole and its chiral metabolite prothioconazole-desthio in five kinds of soils were investigated under native and sterile conditions using reversed phase liquid chromatography tandem mass spectrometry with a Lux-cellulose-1 column. The results showed that an enantioselective degradation was observed with R-prothioconazole preferentially degraded in the five soils and enantiomeric fraction values that ranged from 0.32 to 0.41 under native conditions. Furthermore, the major metabolite prothioconazole-desthio was formed rapidly during prothioconazole dissipation. The prothioconazole-desthio enantiomers were degraded slowly, and there was a slight enantioselectivity with enantiomeric fraction values that ranged from 0.45 to 0.51 in the Nanjing and Jilin soils. Under sterile conditions, prothioconazole and its metabolite enantiomers were more slowly degraded with no enantioselectivity. The result of the incubation experiment with single enantiomers verified that R- and S-prothioconazole were transformed to R- and S-prothioconazole-desthio, respectively. No enantiomerization for prothioconazole and its chiral metabolite was observed. In addition, the excellent correlation between organic matter content and degradation rate indicated that organic matter could promote the degradation of prothioconazole and its metabolite enantiomers. The data in this study provide the experimental evidence of the stereoselective degradation and metabolism of both prothioconazole and its chiral metabolite in the environment.
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Affiliation(s)
- Zhaoxian Zhang
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China
| | - Beibei Gao
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China
| | - Lianshan Li
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China
| | - Qing Zhang
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China
| | - Weitong Xia
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China
| | - Minghua Wang
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China.
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18
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Masbou J, Meite F, Guyot B, Imfeld G. Enantiomer-specific stable carbon isotope analysis (ESIA) to evaluate degradation of the chiral fungicide Metalaxyl in soils. JOURNAL OF HAZARDOUS MATERIALS 2018; 353:99-107. [PMID: 29649698 DOI: 10.1016/j.jhazmat.2018.03.047] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 03/23/2018] [Accepted: 03/24/2018] [Indexed: 05/21/2023]
Abstract
Chiral pesticides are often degraded enantioselectively in soils, leading to disparity among enantiomers that may display different toxicity levels. Monitoring pesticide degradation extents and processes remains out of reach in the field using conventional bulk and enantiomer concentration analyses. Enantioselective stable carbon isotope analysis (ESIA) combines compound specific isotope analysis (CSIA) and enantioselective analysis, and bears potential to distinguish enantiomer degradation from non-destructive dissipation. We developed ESIA of the fungicide Metalaxyl, providing the 13C/12C ratios for S-Metalaxyl and R-Metalaxyl separately, and applied it to follow degradation in soil incubation experiments. Significant enantioselective degradation (kS-MTY = 0.007-0.011 day-1 < kR-MTY = 0.03-0.07 day-1) was associated with isotope fractionation (Δδ13CS-MTY ranging from 2 to 6‰). While R-Metalaxyl degradation was rapid (T1/2≈10 days), concomitant enrichment in heavy isotopes of the persistent S-Metalaxyl occurred after 200 days of incubation (εS-Metalaxyl ranging from -1.3 to -2.7‰). In contrast, initial racemic ratios and isotopic compositions were conserved in abiotic experiments, which indicates the predominance of microbial degradation in soils. Degradation products analysis and apparent kinetic isotope effect (AKIE) suggested hydroxylation as a major enantioselective degradation pathway in our soils. Altogether, our study underscores the potential of ESIA to evaluate the degradation extent and mechanisms of chiral micropollutants in soils.
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Affiliation(s)
- Jérémy Masbou
- Laboratoire d'Hydrologie et de Géochimie de Strasbourg (LHyGeS), Université de Strasbourg/EOST, CNRS, 1 rue Blessig, 67084 Strasbourg Cedex, France
| | - Fatima Meite
- Laboratoire d'Hydrologie et de Géochimie de Strasbourg (LHyGeS), Université de Strasbourg/EOST, CNRS, 1 rue Blessig, 67084 Strasbourg Cedex, France
| | - Benoît Guyot
- Laboratoire d'Hydrologie et de Géochimie de Strasbourg (LHyGeS), Université de Strasbourg/EOST, CNRS, 1 rue Blessig, 67084 Strasbourg Cedex, France
| | - Gwenaël Imfeld
- Laboratoire d'Hydrologie et de Géochimie de Strasbourg (LHyGeS), Université de Strasbourg/EOST, CNRS, 1 rue Blessig, 67084 Strasbourg Cedex, France.
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19
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Huang J, Zhang X, Liang C, Hu J. Impact of TiO 2 on the chemical and biological transformation of formulated chiral-metalaxyl in agricultural soils. JOURNAL OF HAZARDOUS MATERIALS 2018; 348:67-74. [PMID: 29367134 DOI: 10.1016/j.jhazmat.2018.01.035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 01/04/2018] [Accepted: 01/17/2018] [Indexed: 06/07/2023]
Abstract
The impacts of TiO2 on the chemical and biological transformation of racemic metalaxyl wettable powder (rac-metalaxyl WP) in agricultural soils, and soil microorganisms were investigated. Under simulated solar irradiation, TiO2 highly promoted the transformation of rac-metalaxyl WP without changing the enantiomer fraction, with the promotion amplitude (60-1280%) being dependent on TiO2 characteristics. TiO2 characteristics showed different influence on the transformation of rac-metalaxyl WP in soils and aqueous solutions because their characteristics changed differently in soils. The impact of the mancozeb and other co-constituents on the transformation of rac-metalaxyl WP was smaller in soil media than in aqueous solution. Autoclave sterilization changed soil properties and subsequently weakened the promotion effects of TiO2 on the chemical transformations of rac-metalaxyl WP to 0-233%. Microorganism biomass and bacterial community were not statistically significant changed by TiO2 exposure regardless of rac-metalaxyl WP, suggesting that the promotional effects occurred mainly through chemical processes. The results also showed TiO2-soil interactions may be strengthened with TiO2 (Degussa P25) aging time in soils, which decreased its promotion amplitude from 1060% (without aging) to 880% (aging for 20 days). Intermediate formed in soil biological transformation process was different from that in TiO2 photocatalysis process.
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Affiliation(s)
- Junxing Huang
- School of Resources and Environmental Science, Wuhan University, Wuhan, 430079, PR China
| | - Xu Zhang
- School of Resources and Environmental Science, Wuhan University, Wuhan, 430079, PR China.
| | - Chuanzhou Liang
- School of Resources and Environmental Science, Wuhan University, Wuhan, 430079, PR China
| | - Jun Hu
- State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, 430072, PR China
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20
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Zhang J, Lu L, Chen F, Chen L, Yin J, Huang X. Detoxification of diphenyl ether herbicide lactofen by Bacillus sp. Za and enantioselective characteristics of an esterase gene lacE. JOURNAL OF HAZARDOUS MATERIALS 2018; 341:336-345. [PMID: 28802244 DOI: 10.1016/j.jhazmat.2017.07.064] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Revised: 07/26/2017] [Accepted: 07/27/2017] [Indexed: 06/07/2023]
Abstract
A bacterial strain Za capable of degrading diphenyl ether herbicide lactofen was isolated and identified as Bacillus sp. This strain could degrade 94.8% of 50mgL-1 lactofen after 4days of inoculation in flasks. It was revealed that lactofen was initially hydrolyzed to desethyl lactofen, which was further transformed to acifluorfen, followed by the reduction of the nitro group to yield aminoacifluorfen. The phytotoxicity of the transformed product aminoacifluorfen to maize was decreased significantly compared with the lactofen. A gene lacE, encoding an esterase responsible for lactofen hydrolysis to desethyl lactofen and acifluorfen continuously, was cloned from Bacillus sp. Za. The deduced amino acid belonging to the esterase family VII contained a typical Ser-His-Asp/Glu catalytic triad and the conserved motifs GXSXG. The purified recombinant protein LacE displayed maximal esterase activity at 40°C and pH 7.0. Additionally, LacE had broad substrate specificity and was capable of hydrolyzing p-nitrophenyl esters. The enantioselectivity of LacE during lactofen degradation was further studied, and the results indicated that the (S)-(+)-lactofen was degraded faster than the (R)-(-)-lactofen, which could illustrate the reported phenomenon that (S)-(+)-lactofen was preferentially degraded in soil and sediment.
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Affiliation(s)
- Jing Zhang
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China; Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Luyao Lu
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Feng Chen
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Lingling Chen
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Jingang Yin
- Laboratory of Biocatalysis and Synthetic Biotechnology, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Xing Huang
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
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21
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Marie L, Sylvain P, Benoit G, Maurice M, Gwenaël I. Degradation and Transport of the Chiral Herbicide S-Metolachlor at the Catchment Scale: Combining Observation Scales and Analytical Approaches. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:13231-13240. [PMID: 29056040 DOI: 10.1021/acs.est.7b02297] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Evaluating pesticide degradation and transport in the soil-surface water continuum remains challenging at the catchment scale. Here we investigated the dissipation of the chiral herbicide S-metolachlor (SM) in soil in relation to its transport in runoff. Analyses of SM, transformation products (TPs, i.e., MESA and MOXA), and enantiomers were combined to determine SM degradation at plot and catchment scales. Assisted by modeling, we found that the main dissipation pathways of SM at the plot scale were degradation (71%), volatilization (5%), leaching (8%) and runoff (3%), while 13% of SM persisted in topsoil. This highlights the relevance of degradation processes. TPs could trace the different discharge contributions: MOXA prevailed in runoff water, whereas MESA was associated with slower flowpaths. At the catchment outlet, 11% of SM applied was exported in dissolved or particulate phases or as TPs (in SM mass equivalent). A single event 1 week after application exported 96% of SM, which underlined the potential importance of severe rainfall on seasonal SM export. Enantioselective degradation enriched SM in the R-enantiomer over longer periods and may be associated with slower flowpaths. Altogether, combining observation scales and analytical approaches enabled to quantify SM degradation and to identify how degradation controls SM export at the catchment scale.
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Affiliation(s)
- Lefrancq Marie
- Laboratory of Hydrology and Geochemistry of Strasbourg (LHyGeS UMR 7517), University of Strasbourg, CNRS, ENGEES , 1 Rue Blessig, 67084 Strasbourg cedex, France
- LETG-Angers (UMR CNRS 6554), University of Angers , 2 bd Lavoisier, 49045 Angers, France
| | - Payraudeau Sylvain
- Laboratory of Hydrology and Geochemistry of Strasbourg (LHyGeS UMR 7517), University of Strasbourg, CNRS, ENGEES , 1 Rue Blessig, 67084 Strasbourg cedex, France
| | - Guyot Benoit
- Laboratory of Hydrology and Geochemistry of Strasbourg (LHyGeS UMR 7517), University of Strasbourg, CNRS, ENGEES , 1 Rue Blessig, 67084 Strasbourg cedex, France
| | - Millet Maurice
- Atmospheric Physical Chemistry Department (ICPEES UMR 7515), University of Strasbourg, CNRS , 1 rue Blessig, 67084 Strasbourg cedex, France
| | - Imfeld Gwenaël
- Laboratory of Hydrology and Geochemistry of Strasbourg (LHyGeS UMR 7517), University of Strasbourg, CNRS, ENGEES , 1 Rue Blessig, 67084 Strasbourg cedex, France
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22
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Sanganyado E, Lu Z, Fu Q, Schlenk D, Gan J. Chiral pharmaceuticals: A review on their environmental occurrence and fate processes. WATER RESEARCH 2017; 124:527-542. [PMID: 28806704 DOI: 10.1016/j.watres.2017.08.003] [Citation(s) in RCA: 142] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Revised: 08/01/2017] [Accepted: 08/02/2017] [Indexed: 05/20/2023]
Abstract
More than 50% of pharmaceuticals in current use are chiral compounds. Enantiomers of the same pharmaceutical have identical physicochemical properties, but may exhibit differences in pharmacokinetics, pharmacodynamics and toxicity. The advancement in separation and detection methods has made it possible to analyze trace amounts of chiral compounds in environmental media. As a result, interest on chiral analysis and evaluation of stereoselectivity in environmental occurrence, phase distribution and degradation of chiral pharmaceuticals has grown substantially in recent years. Here we review recent studies on the analysis, occurrence, and fate of chiral pharmaceuticals in engineered and natural environments. Monitoring studies have shown ubiquitous presence of chiral pharmaceuticals in wastewater, surface waters, sediments, and sludge, particularly β-receptor antagonists, analgesics, antifungals, and antidepressants. Selective sorption and microbial degradation have been demonstrated to result in enrichment of one enantiomer over the other. The changes in enantiomer composition may also be caused by biologically catalyzed chiral inversion. However, accurate evaluation of chiral pharmaceuticals as trace environmental pollutants is often hampered by the lack of identification of the stereoconfiguration of enantiomers. Furthermore, a systematic approach including occurrence, fate and transport in various environmental matrices is needed to minimize uncertainties in risk assessment of chiral pharmaceuticals as emerging environmental contaminants.
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Affiliation(s)
- Edmond Sanganyado
- Department of Environmental Sciences, University of California, Riverside, CA, 92521, United States.
| | - Zhijiang Lu
- Department of Environmental Sciences, University of California, Riverside, CA, 92521, United States
| | - Qiuguo Fu
- Department of Environmental Sciences, University of California, Riverside, CA, 92521, United States; Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600, Dübendorf, Switzerland
| | - Daniel Schlenk
- Department of Environmental Sciences, University of California, Riverside, CA, 92521, United States
| | - Jay Gan
- Department of Environmental Sciences, University of California, Riverside, CA, 92521, United States
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Huang J, Liang C, Zhang X. Effects of nano-SiO 2 on the adsorption of chiral metalaxyl to agricultural soils. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2017; 225:201-210. [PMID: 28388518 DOI: 10.1016/j.envpol.2017.03.065] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Revised: 03/16/2017] [Accepted: 03/27/2017] [Indexed: 06/07/2023]
Abstract
The application of nanotechnology in agriculture, pesticide delivery and other related fields increases the occurrence of engineered nanoparticles (ENPs) in soil. Since ENPs have larger surface areas and normally a high adsorption capacity for organic pollutants, they are thought to influence the transport of pesticides in soils and thereafter influence the uptake and transformation of pesticides. The adsorption pattern of racemic-metalaxyl on agricultural soils including kinetics and isotherms changed in the presence of nano-SiO2. The adsorption of racemic-metalaxyl on agricultural soil was not enantioselective, in either the presence or the absence of SiO2. The adsorption of racemic-metalaxyl on SiO2 decreased to some extent in soil-SiO2 mixture, and the absolute decrease was dependent on soil properties. The decreased adsorption of metalaxyl on SiO2 in soil-SiO2 mixture arose from the competitive adsorption of soil-dissolved organic matter and the different dispersion and aggregation behaviors of SiO2 in the presence of soil. Interactions between SiO2 and soil particles also contributed to the decreased adsorption of metalaxyl on SiO2, and the interactions were analyzed by extended Derjaguin-Landau-Verwey-Overbeek theory. The results showed that the presence of nano-particles in soils could decrease the mobility of pesticides in soils and that this effect varied with different soil compositions.
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Affiliation(s)
- Junxing Huang
- School of Resources and Environmental Science, Wuhan University, Wuhan, 430079, China
| | - Chuanzhou Liang
- School of Resources and Environmental Science, Wuhan University, Wuhan, 430079, China
| | - Xu Zhang
- School of Resources and Environmental Science, Wuhan University, Wuhan, 430079, China.
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24
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Di S, Liu R, Cheng C, Chen L, Zhang W, Tian Z, Liu C, Zhou Z, Diao J. Biomarkers in Tubifex tubifex for the metalaxyl and metalaxyl-M toxicity assessment in artificial sediment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:3618-3625. [PMID: 27882496 DOI: 10.1007/s11356-016-8128-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 11/17/2016] [Indexed: 06/06/2023]
Abstract
Efficacy and potential environmental risks should be considered when applying enantiopure pesticides. In this study, Tubifex tubifex and its oxidative stress biomarkers were assessed for the toxicity of metalaxyl and metalaxyl-M in sediment. The toxicity assessment was conducted with artificial sediment and reconstituted water. Five test concentrations (from 0 to 100 mg/kg) were set for the short-term (4 days) exposure. The long-term (28 days) exposure was conducted with the environmental concentration (from 0.5 to 5 mg/kg). For the short-term exposure, the increase of superoxide dismutase (SOD) activity was observed, and a clear concentration-response relationship was found in the metalaxyl treatments. The decrease of catalase (CAT) and glutathione peroxidase (GPx) activity could be caused by oxidative stress. The decrease of glutathione (GSH) content and the increase of glutathione-S-transferase (GST) might be due to antioxidation defense and detoxification mechanisms. The increase of malondialdehyde (MDA) might be due to the saturation of antioxidant systems and the accumulation and toxicity of contaminations. In the long-term exposure, the changes of biomarkers in T. tubifex reflected the oxidative stress and detoxification metabolisms. GSH and the related enzymes were important in detoxification processes and involved in the oxidative stress in toxicity mechanism. The long-term direct contact bioassay is sensitive and appropriate to reflect the lower concentration of contaminants.
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Affiliation(s)
- Shanshan Di
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, China
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, People's Republic of China
| | - Ruiquan Liu
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, People's Republic of China
| | - Cheng Cheng
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, People's Republic of China
| | - Li Chen
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, China
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, People's Republic of China
| | - Wenjun Zhang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, China
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, People's Republic of China
| | - Zhongnan Tian
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, People's Republic of China
| | - Chunxiao Liu
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, People's Republic of China
| | - Zhiqiang Zhou
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, China
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, People's Republic of China
| | - Jinling Diao
- Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing, 100193, People's Republic of China.
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Liang C, Huang J, Zhang X. Effects of Engineered Nanoparticles on the Enantioselective Transformation of Metalaxyl Agent and Commercial Metalaxyl in Agricultural Soils. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2016; 64:7688-7695. [PMID: 27690422 DOI: 10.1021/acs.jafc.6b02961] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The adsorption coefficient of racemic metalaxyl onto an agriculture soil was small and nonenantioselective. Biotransformation was the predominant pathway for the elimination of R-metalaxyl, while abiotic and biotransformation made a comparable contribution to the degradation of S-metalaxyl. Metalaxyl acid was the main transformation intermediate. The enantiomer fraction of metalaxyl decreased with an increase in its initial spike concentration or the presence of the co-constituents in metalaxyl commercial products. Under simulated solar irradiation, the presence of TiO2 promoted the overall transformation kinetics through enhanced biotransformation and extra photoinduced chemical reactions. The promotion was enantioselective and thereafter changed the enantiomer fraction. The results obtained in this study showed that some achiral parameters, although they have no direct impact on enantioselective reactions with enantiomers, can significantly affect the enantioselective transformation of racemic metalaxyl. Thus, our results indicate that the contribution of chemical interactions on the enantioselective transformation of chiral pesticides may be underestimated.
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Affiliation(s)
- Chuanzhou Liang
- School of Resources and Environmental Science, Wuhan University , Wuhan 430079, P.R. China
| | - Junxing Huang
- School of Resources and Environmental Science, Wuhan University , Wuhan 430079, P.R. China
| | - Xu Zhang
- School of Resources and Environmental Science, Wuhan University , Wuhan 430079, P.R. China
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26
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López-Cabeza R, Cornejo J, Celis R. Evaluation of an organo-layered double hydroxide and two organic residues as amendments to immobilize metalaxyl enantiomers in soils: A comparative study. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2016; 181:135-145. [PMID: 27341374 DOI: 10.1016/j.jenvman.2016.06.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 06/10/2016] [Accepted: 06/13/2016] [Indexed: 06/06/2023]
Abstract
Many pollutants released into the environment as a result of human activities are chiral. Pollution control strategies generally consider chiral compounds as if they were achiral and rarely consider enantiomers separately. We compared the performance of three different materials, an organically-modified anionic clay (HT-ELA) and two organic agro-food residues (ALP and ALPc), as amendments to immobilize the chiral fungicide metalaxyl in two soils with different textures, addressing the effects of the amendments on the sorption, persistence, and leaching of each of the two enantiomers of metalaxyl (R-metalaxyl and S-metalaxyl) separately. The effects of the amendments were both soil- and amendment-dependent, as well as enantiomer-selective. The organo-clay (HT-ELA) was much more efficient in increasing the sorption capacity of the soils for the two enantiomers of metalaxyl than the agro-food residues (ALP and ALPc), even when applied at a reduced application rate. The enhanced sorption in HT-ELA-amended soils reduced the bioavailability of metalaxyl enantiomers and their leaching in the soils, mitigating the particularly high leaching potential of the more persistent S enantiomer. The immobilizing capacity of the agro-food residues was more variable, mainly because their addition did not greatly ameliorate the sorption capacity of the soils and had variable effects on the enantiomers degradation rates. HT-ELA showed potential to reduce the bioavailability and mobility of metalaxyl enantiomers in soil and to mitigate the contamination problems particularly associated with the higher leaching potential of the more persistent enantiomer.
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Affiliation(s)
- Rocío López-Cabeza
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, 41012 Sevilla, Spain
| | - Juan Cornejo
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, 41012 Sevilla, Spain
| | - Rafael Celis
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, 41012 Sevilla, Spain.
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27
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Gámiz B, Facenda G, Celis R. Evidence for the effect of sorption enantioselectivity on the availability of chiral pesticide enantiomers in soil. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 213:966-973. [PMID: 27060281 DOI: 10.1016/j.envpol.2016.03.052] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 03/10/2016] [Accepted: 03/20/2016] [Indexed: 06/05/2023]
Abstract
Although enantioselective sorption to soil particles has been proposed as a mechanism that can potentially influence the availability of individual chiral pesticide enantiomers in the environment, environmental fate studies generally overlook this possibility and assume that only biotic processes can be enantioselective, whereas abiotic processes, such as sorption, are non-enantioselective. In this work, we present direct evidence for the effect of the enantioselective sorption of a chiral pesticide in a natural soil on the availability of the single pesticide enantiomers for transport. Batch sorption experiments, with direct determination of the sorbed amounts, combined with column leaching tests confirmed previous observations that from non-racemic aqueous solutions the sorption of the chiral fungicide metalaxyl on the soil appeared to be enantioselective, and further demonstrated that the enantiomer that was sorbed to a greater extent (R-metalaxyl, Kd = 1.73 L/kg) exhibited retarded leaching compared to its optical isomer (S-metalaxyl, Kd = 1.15 L/kg). Interconversion and degradation of the pesticide enantiomers, which are potential experimental artifacts that can lead to erroneous estimates of sorption and its enantioselectivity, were discarded as possible causes of the observed enantioselective behavior. The results presented here may have very important implications for a correct assessment of the environmental fate of chiral pesticides that are incorporated into the environment as non-racemic mixtures, and also of aged chiral pesticide residues that have been transformed from racemic to non-racemic by biologically-mediated processes.
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Affiliation(s)
- Beatriz Gámiz
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, 41012 Sevilla, Spain
| | - Gracia Facenda
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, 41012 Sevilla, Spain
| | - Rafael Celis
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, 41012 Sevilla, Spain.
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28
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Gámiz B, Pignatello JJ, Cox L, Hermosín MC, Celis R. Environmental fate of the fungicide metalaxyl in soil amended with composted olive-mill waste and its biochar: An enantioselective study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 541:776-783. [PMID: 26433334 DOI: 10.1016/j.scitotenv.2015.09.097] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 09/10/2015] [Accepted: 09/18/2015] [Indexed: 06/05/2023]
Abstract
A large number of pesticides are chiral and reach the environment as mixtures of optical isomers or enantiomers. Agricultural practices can affect differently the environmental fate of the individual enantiomers. We investigated how amending an agricultural soil with composted olive-mill waste (OMWc) or its biochar (BC) at 2% (w:w) affected the sorption, degradation, and leaching of each of the two enantiomers of the chiral fungicide metalaxyl. Sorption of metalaxyl enantiomers was higher on BC (Kd ≈ 145 L kg(-1)) than on OMWc (Kd ≈ 22 L kg(-1)) and was not enantioselective in either case, and followed the order BC-amended>OMWc-amended>unamended soil. Both enantiomers showed greater resistance to desorption from BC-amended soil compared to unamended and OMWc-amended soil. Dissipation studies revealed that the degradation of metalaxyl was more enantioselective (R>S) in unamended and OMWc-amended soil than in BC-amended soil. The leaching of both S- and R-metalaxyl from soil columns was almost completely suppressed after amending the soil with BC and metalaxyl residues remaining in the soil columns were more racemic than those in soil column leachates. Our findings show that addition of BC affected the final enantioselective behavior of metalaxyl in soil indirectly by reducing its bioavailability through sorption, and to a greater extent than OMWc. BC showed high sorption capacity to remove metalaxyl enantiomers from water, immobilize metalaxyl enantiomers in soil, and mitigate the groundwater contamination problems particularly associated with the high leaching potential of the more persistent enantiomer.
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Affiliation(s)
- Beatriz Gámiz
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, P.O. Box 1052, 41080 Sevilla, Spain.
| | - Joseph J Pignatello
- Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, 123 Huntington St., P.O. Box 1106, New Haven, CT 06504-1106, United States
| | - Lucía Cox
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, P.O. Box 1052, 41080 Sevilla, Spain
| | - María C Hermosín
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, P.O. Box 1052, 41080 Sevilla, Spain
| | - Rafael Celis
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, P.O. Box 1052, 41080 Sevilla, Spain
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29
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Celis R, Gámiz B, Facenda G, Hermosín MC. Enantioselective sorption of the chiral fungicide metalaxyl on soil from non-racemic aqueous solutions: Environmental implications. JOURNAL OF HAZARDOUS MATERIALS 2015; 300:581-589. [PMID: 26259163 DOI: 10.1016/j.jhazmat.2015.07.059] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 07/21/2015] [Accepted: 07/23/2015] [Indexed: 06/04/2023]
Abstract
Mechanisms governing the enantioselectivity of the processes that determine the behavior of chiral pollutants in the environment need to be better understood. Understanding these mechanisms should help improve predictions of the hazards and risks chiral compounds can pose to people and the environment. We report the results of batch sorption experiments indicating that the sorption of the chiral fungicide metalaxyl on soil from non-racemic initial solutions was enantioselective. While from a racemic initial solution the two enantiomers of metalaxyl were sorbed on the soil to the same extent, increasing the fraction of R-enantiomer in the initial solution led to enhanced sorption of this enantiomer and to reduced sorption of the S-enantiomer. Considering the shape of the sorption isotherms (S-type) and the sorption behavior of model sorbents, we attributed this effect to molecular interactions between metalaxyl enantiomer species at the sorbed state, where R-R metalaxyl interactions appeared to be more favorable than R-S metalaxyl interactions. We discuss important environmental implications of the proposed mechanism, such as those related to the fact that the biological degradation of metalaxyl is known to be an enantioselective process that can yield non-racemic residues in soils shortly after application of the fungicide as a racemic mixture.
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Affiliation(s)
- Rafael Celis
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, P.O. Box 1052, 41080 Sevilla, Spain.
| | - Beatriz Gámiz
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, P.O. Box 1052, 41080 Sevilla, Spain
| | - Gracia Facenda
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, P.O. Box 1052, 41080 Sevilla, Spain
| | - María C Hermosín
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, P.O. Box 1052, 41080 Sevilla, Spain
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30
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Celis R, Gámiz B, Adelino MA, Cornejo J, Hermosín MC. Effect of formulation and repeated applications on the enantioselectivity of metalaxyl dissipation and leaching in soil. PEST MANAGEMENT SCIENCE 2015; 71:1572-1581. [PMID: 25492063 DOI: 10.1002/ps.3963] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Revised: 10/06/2014] [Accepted: 12/04/2014] [Indexed: 06/04/2023]
Abstract
BACKGROUND Soil incubation and column leaching experiments were conducted to address the question of whether the type of formulation (unsupported versus clay supported) and repeated applications of the chiral fungicide (RS)-metalaxyl affected the enantioselectivity of its dissipation and leaching in a slightly alkaline, loamy sand agricultural soil. RESULTS Regardless of the type of formulation and the number of fungicide applications, the R-enantiomer of metalaxyl was degraded faster than the S-enantiomer, but the individual degradation rates of R- and S-metalaxyl were highly affected by the different application regimes assayed (t1/2 = 2-104 days). Repeated applications accelerated the degradation of the biologically active R-metalaxyl enantiomer, whereas they led to slower degradation of the non-active S-metalaxyl enantiomer. The type of formulation had less influence on the dissipation rates of the enantiomers. For all formulations tested, soil column leachates became increasingly enriched in S-enantiomer as the number of fungicide applications was increased, and application of metalaxyl to soil columns as clay-based formulations reduced the leaching of both enantiomers. CONCLUSION Pesticide application conditions can greatly influence the enantioselective dissipation of chiral pesticides in soil, and hence are expected to exert a great impact on both the biological efficacy and the environmental chiral signatures of pesticides applied as mixtures of enantiomers or racemates to agricultural soils.
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Affiliation(s)
- Rafael Celis
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Seville, Spain
| | - Beatriz Gámiz
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Seville, Spain
| | - María A Adelino
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Seville, Spain
| | - Juan Cornejo
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Seville, Spain
| | - María C Hermosín
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Seville, Spain
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31
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Liu Y, Zhang X, Liu C, Yang R, Xu Z, Zhou L, Sun Y, Lei H. Enantioselective and Synergetic Toxicity of Axial Chiral Herbicide Propisochlor to SP2/0 Myeloma Cells. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:7914-7920. [PMID: 26299567 DOI: 10.1021/acs.jafc.5b03027] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The axial chiral herbicide propisochlor is used to control weeds. Different enantiomers of a compound usually have different biological activities. It is unclear how the toxicities of the propisochlor enantiomers differ. Propisochlor enantiomers, separated by high-performance liquid chromatography, were tested on SP2/0 myeloma cells. Cytotoxicity and apoptosis were measured, and interactions between the enantiomers were evaluated. The rac-propisochlor, pure R-(+) isomer, and pure S-(-) isomer inhibited cell proliferation and induced apoptosis. The rac-propisochlor, R-(+) isomer, and S-(-) isomer half maximal effective concentration values after 24 h of incubation were 111 ± 0.15, 68 ± 0.09, and 99 ± 0.21 μM, respectively. R-(+) isomer induced the most apoptosis. R-(+) isomer was ∼1.63 times more cytotoxic than rac-propisochlor and ∼1.46 times more cytotoxic than S-(-) isomer. Antagonistic cytotoxic interactions were found between R-(+) and S-(-) isomers. This is the first time the toxicities of these enantiomers and antagonism between the enantiomers have been reported. The antagonism indicates that the ecotoxicological effects of the enantiomers should be investigated.
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Affiliation(s)
- Yao Liu
- Guangdong Provincial Key Laboratory of Food Quality and Safety, College of Food Science, South China Agricultural University , Guangzhou, Guangdong 510642, People's Republic of China
| | - Xuan Zhang
- Guangdong Provincial Key Laboratory of Food Quality and Safety, College of Food Science, South China Agricultural University , Guangzhou, Guangdong 510642, People's Republic of China
| | - Chunhong Liu
- Guangdong Provincial Key Laboratory of Food Quality and Safety, College of Food Science, South China Agricultural University , Guangzhou, Guangdong 510642, People's Republic of China
| | - Ruili Yang
- Guangdong Provincial Key Laboratory of Food Quality and Safety, College of Food Science, South China Agricultural University , Guangzhou, Guangdong 510642, People's Republic of China
| | - Zhenlin Xu
- Guangdong Provincial Key Laboratory of Food Quality and Safety, College of Food Science, South China Agricultural University , Guangzhou, Guangdong 510642, People's Republic of China
| | - Lijun Zhou
- Central Laboratory, Navy General Hospital , Beijing 100048, People's Republic of China
| | - Yuanming Sun
- Guangdong Provincial Key Laboratory of Food Quality and Safety, College of Food Science, South China Agricultural University , Guangzhou, Guangdong 510642, People's Republic of China
| | - Hongtao Lei
- Guangdong Provincial Key Laboratory of Food Quality and Safety, College of Food Science, South China Agricultural University , Guangzhou, Guangdong 510642, People's Republic of China
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32
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Pan R, Chen H, Wang C, Wang Q, Jiang Y, Liu X. Enantioselective Dissipation of Acephate and Its Metabolite, Methamidophos, during Tea Cultivation, Manufacturing, and Infusion. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:1300-1308. [PMID: 25582130 DOI: 10.1021/jf504916b] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The enantioselective dissipation of acephate and its metabolite, methamidophos, was investigated during tea cultivation, manufacturing, and infusion, using QuEChERS sample preparation technique and gas chromatography coupled with a BGB-176 chiral column. Results showed that (+)-acephate and (-)-acephate dissipated following first-order kinetics in fresh tea leaves with half-lives of 1.8 and 1.9 days, respectively. Acephate was degraded into a more toxic metabolite, methamidophos. Preferential dissipation and translocation of (+)-acephate may exist in tea shoots, and (-)-methamidophos was degraded more rapidly than (+)-methamidophos. During tea manufacturing, drying and spreading (or withering) played important roles in the dissipation of acephate enantiomers. The enantiometic fractions of acephate changed from 0.495-0.496 to 0.479-0.486 (P ≤ 0.0081), whereas those of methamidophos changed from 0.576-0.630 to 0.568-0.645 (P ≤ 0.0366 except for green tea manufacturing on day 1), from fresh tea leaves to made tea. In addition, high transfer rates (>80%) and significant enantioselectivity (P ≤ 0.0042) of both acephate and its metabolite occurred during tea brewing.
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Affiliation(s)
- Rong Pan
- Tea Research Institute, Chinese Academy of Agricultural Sciences , Hangzhou 310008, China
- Graduate School of Chinese Academy of Agricultural Sciences , Beijing 100081, China
| | - Hongping Chen
- Tea Research Institute, Chinese Academy of Agricultural Sciences , Hangzhou 310008, China
- Key Laboratory of Tea Quality and Safety & Risk Assessment, Ministry of Agriculture, Hangzhou 310008, China
| | - Chen Wang
- Tea Research Institute, Chinese Academy of Agricultural Sciences , Hangzhou 310008, China
- Key Laboratory of Tea Quality and Safety & Risk Assessment, Ministry of Agriculture, Hangzhou 310008, China
| | - Qinghua Wang
- Tea Research Institute, Chinese Academy of Agricultural Sciences , Hangzhou 310008, China
- Key Laboratory of Tea Quality and Safety & Risk Assessment, Ministry of Agriculture, Hangzhou 310008, China
| | - Ying Jiang
- Tea Research Institute, Chinese Academy of Agricultural Sciences , Hangzhou 310008, China
- Key Laboratory of Tea Quality and Safety & Risk Assessment, Ministry of Agriculture, Hangzhou 310008, China
| | - Xin Liu
- Tea Research Institute, Chinese Academy of Agricultural Sciences , Hangzhou 310008, China
- Key Laboratory of Tea Quality and Safety & Risk Assessment, Ministry of Agriculture, Hangzhou 310008, China
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Zhang Y, Hu D, Meng X, Shi Q, Li P, Jin L, Zhang K, Song B. Enantioselective Degradation of Indoxacarb From Different Commercial Formulations Applied to Tea. Chirality 2015; 27:262-7. [DOI: 10.1002/chir.22422] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 11/12/2014] [Accepted: 12/09/2014] [Indexed: 11/06/2022]
Affiliation(s)
- Yuping Zhang
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education; Guizhou University; Guiyang P.R. China
- Center for Research and Development of Fine Chemicals; Guizhou University; Guiyang P.R. China
| | - Deyu Hu
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education; Guizhou University; Guiyang P.R. China
- Center for Research and Development of Fine Chemicals; Guizhou University; Guiyang P.R. China
| | - Xingang Meng
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education; Guizhou University; Guiyang P.R. China
| | - Qingcai Shi
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education; Guizhou University; Guiyang P.R. China
| | - Pei Li
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education; Guizhou University; Guiyang P.R. China
- Center for Research and Development of Fine Chemicals; Guizhou University; Guiyang P.R. China
| | - Linhong Jin
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education; Guizhou University; Guiyang P.R. China
- Center for Research and Development of Fine Chemicals; Guizhou University; Guiyang P.R. China
| | - Kankan Zhang
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education; Guizhou University; Guiyang P.R. China
- Center for Research and Development of Fine Chemicals; Guizhou University; Guiyang P.R. China
| | - Baoan Song
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education; Guizhou University; Guiyang P.R. China
- Center for Research and Development of Fine Chemicals; Guizhou University; Guiyang P.R. China
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Elmekawy AA, Sweeney JB, Brown DR. Efficient synthesis of supported proline catalysts for asymmetric aldol reactions. Catal Sci Technol 2015. [DOI: 10.1039/c4cy00970c] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
l-Proline is grafted onto silica (MCM-41) in a single step and shows high activity and enantioselectivity in an aldol reaction.
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Affiliation(s)
- A. A. Elmekawy
- Department of Chemical Sciences
- University of Huddersfield
- UK
| | - J. B. Sweeney
- Department of Chemical Sciences
- University of Huddersfield
- UK
| | - D. R. Brown
- Department of Chemical Sciences
- University of Huddersfield
- UK
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35
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Zhang YP, Hu DY, Ling HR, Zhong L, Huang AX, Zhang KK, Song BA. Comparative study of the selective degradations of two enantiomers in the racemate and an enriched concentration of indoxacarb in soils. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2014; 62:9066-9072. [PMID: 25134952 DOI: 10.1021/jf5018803] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In this study, selective degradations of the two enantiomers of indoxacarb in the concentrate (2.33S/1R) and racemate (1S/1R) are examined. The absolute configurations of indoxacarb enantiomers were determined using X-ray diffraction. The results showed that in two alkaline soils, the S-(+)-indoxacarb was preferentially degraded in both the concentrate and racemate. In one acid soil, the two enantiomers degraded no-selectivity. In another acid soil and one neutral soil, the R-(-)-indoxacarb was preferentially degraded in both the concentrate and racemate. Indoxacarb enantiomers were configurationally stable in the five soils, and no interconversion was observed during the incubation. Because no significant difference in degradation was observed after samples were sterilized, the observed enantioselectivity may be attributed primarily to microbial activity in soils. The results indicate that the selective degradation behavior was the same for both formulations that were tested.
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Affiliation(s)
- Yu-Ping Zhang
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University , Huaxi District, Guiyang 550025, PR China
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36
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Qin F, Gao Y, Guo B, Xu P, Li J, Wang H. Enantioselective Acute Toxicity Effects and Bioaccumulation of Furalaxyl in the Earthworm (Eisenia foetida
). Chirality 2014; 26:307-12. [DOI: 10.1002/chir.22323] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 01/12/2014] [Accepted: 02/27/2014] [Indexed: 11/06/2022]
Affiliation(s)
- Fang Qin
- Research Center for Eco-Environmental Sciences; Chinese Academy of Sciences; Beijing China
| | - Yongxin Gao
- Research Center for Eco-Environmental Sciences; Chinese Academy of Sciences; Beijing China
| | - Baoyuan Guo
- Research Center for Eco-Environmental Sciences; Chinese Academy of Sciences; Beijing China
| | - Peng Xu
- Research Center for Eco-Environmental Sciences; Chinese Academy of Sciences; Beijing China
| | - Jianzhong Li
- Research Center for Eco-Environmental Sciences; Chinese Academy of Sciences; Beijing China
| | - Huili Wang
- Research Center for Eco-Environmental Sciences; Chinese Academy of Sciences; Beijing China
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37
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Zhang Y, Zhang K, Song B, Ling H, Li Z, Li M, Hu D. Enantiomeric separation of indoxacarb on an amylose-based chiral stationary phase and its application in study of indoxacarb degradation in water. Biomed Chromatogr 2014; 28:1371-7. [PMID: 24687873 DOI: 10.1002/bmc.3178] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 02/02/2014] [Accepted: 02/08/2014] [Indexed: 11/07/2022]
Abstract
Direct semipreparative enantioseparation of indoxacarb was performed on a semipreparative Chiralpak IA column using normal-phase high-performance liquid chromatography (HPLC) with n-hexane-isopropanol-ethyl acetate (70:20:10) mixture as mobile phase. Degradation of indoxacarb (2.33S + 1R) and its two enantiopure isoforms in three aqueous buffer solutions and four water samples collected from natural water sources was then elucidated by HPLC analysis on Chiralpak IA column. Degradation of all three indoxacarbs complied with first-order kinetics and demonstrated linearity with regression coefficients R(2) > n0.88. Indoxacarb (2.33S + 1R) underwent enantioselective degradation in river water, rain water, and buffer solution of pH 7.0. Enantiopure S-(+)-indoxacarb and R-(-)-indoxacarb were both found to be configurationally stable in water.
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Affiliation(s)
- Yuping Zhang
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Guizhou University, Guiyang, 550025, China
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Qin F, Gao YX, Guo BY, Xu P, Li JZ, Wang HL. Environmental behavior of benalaxyl and furalaxyl enantiomers in agricultural soils. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART. B, PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES 2014; 49:738-746. [PMID: 25065825 DOI: 10.1080/03601234.2014.929482] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The enantioselective environmental behavior of the chiral fungicides benalaxy and furalaxyl in agricultural soils in China was studied. Although sorption onto soils was non-enantioselective, the leaching of benalaxy and furalaxyl was enantioselective in soil columns. The concentrations of the S-enantiomers of both fungicides in the leachates were higher than the R-enantiomers. This can be attributed to enantioselective degradation of the two fungicides in the soil column. Enantioselective degradation of the two fungicides was verified by soil dissipation experiments, and the R-enantiomers degraded faster than the S-enantiomers in partial soils. The half-life was 27.7-57.8 days for S-benalaxyl, 20.4-53.3 days for R-benalaxyl, 19.3-49.5 days for S-furalaxyl and 11.4-34.7 days for R-furalaxyl. The degradation process of the two fungicide enantiomers followed the first-order kinetics (R(2) > 0.96). Compared to furalaxyl, benalaxyl degraded more slowly and degradation was less enantioselective. These results are attributed to the influence of soil physicochemical properties, soil microorganisms, and environmental factors.
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Affiliation(s)
- Fang Qin
- a Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing , China
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39
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Botterweck J, Claßen D, Zegarski T, Gottfroh C, Kalathoor R, Schäffer A, Schwarzbauer J, Schmidt B. A correlation between the fate and non-extractable residue formation of 14C-metalaxyl and enzymatic activities in soil. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART. B, PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES 2014; 49:69-78. [PMID: 24328538 DOI: 10.1080/03601234.2014.844600] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
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.
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Affiliation(s)
- Jens Botterweck
- a Institute for Environmental Research , RWTH Aachen University , Aachen , Germany
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40
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Gámiz B, Celis R, Hermosín MC, Cornejo J. Effect of olive-mill waste addition to agricultural soil on the enantioselective behavior of the chiral fungicide metalaxyl. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2013; 128:92-99. [PMID: 23722178 DOI: 10.1016/j.jenvman.2013.04.055] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 04/16/2013] [Accepted: 04/22/2013] [Indexed: 06/02/2023]
Abstract
Certain soil management practices can affect the enantioselective behavior of chiral pesticide enantiomers in agricultural soils. In this work, laboratory experiments were conducted to study the effects of olive-mill waste (OMW) addition to a Mediterranean agricultural soil on the enantioselectivity of sorption, degradation, and leaching processes of the chiral fungicide metalaxyl. Sorption-desorption isotherms indicated that the sorption of metalaxyl enantiomers by unamended and OMW-amended soil (2% w/w) was non-enantioselective and that OMW addition had little effect on the extent of sorption of metalaxyl enantiomers by the soil. Soil incubation experiments revealed that the degradation of metalaxyl in unamended soil was highly enantioselective, with R-metalaxyl being degraded faster (t1/2 = 12 days) than S-metalaxyl (t1/2 = 39 days). OMW addition to the soil increased the half-life of the biologically-active R-metalaxyl enantiomer from 12 to 28 days, and decreased the half-life of the non-active S-metalaxyl enantiomer from 39 to 33 days. Consequently, the enantioselectivity of metalaxyl degradation in the soil was greatly reduced upon OMW addition. Column leaching data were consistent with batch sorption and incubation results, showing similar retardation of S- and R-metalaxyl in unamended and OMW-amended soil and enantioselective leaching of the fungicide only in unamended soil. The results have important implications regarding the biological efficacy and environmental impact of the fungicide when applied as a mixture of enantiomers or racemate to OMW-treated soils.
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Affiliation(s)
- Beatriz Gámiz
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Avenida Reina Mercedes 10, P.O. Box 1052, 41080 Sevilla, Spain.
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