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M Paramasivam - One of the best experts on this subject based on the ideXlab platform.
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dissipation behavior of Phorate and its toxic metabolites in the sandy clay loam soil of a tropical sugarcane ecosystem using a single step sample preparation method and gc ms
IEEE Journal of Solid-state Circuits, 2016Co-Authors: Thirumalaiandi Ramasubramanian, M ParamasivamAbstract:The dissipation of Phorate in the sandy clay loam soil of tropical sugarcane ecosystem was studied by employing a single-step sample preparation method and gas chromatography with mass spectrometry. The limit of quantification of the method was 0.01 μg/g. The recoveries of Phorate, Phorate sulfoxide, Phorate sulfone and Phorate oxon were in the range 94.00–98.46% with relative standard deviations of 1.51–3.56% at three levels of fortification between 0.01 and 0.1 μg/g. Half-life of Phorate and the total residues, which include Phorate, Phorate sulfoxide and Phorate sulfone was 5.5 and 19.8 days, respectively at the recommended dose of insecticide. Phorate rapidly oxidized into its sulfoxide metabolite in the sandy clay loam soil. Phorate sulfoxide alone accounted for more than 20% of the total residues within 2 h post-application and it was more than 50% on the fifth day after treatment irrespective of the doses applied. Phorate sulfoxide and Phorate sulfone reached below the detectable level on 105 and 135 days after treatment, respectively as against 45 days after treatment for Phorate residues at the recommended dose. Thus, the reasonably prolonged efficacy of Phorate against soil pests may be attributed to longer persistence of its more toxic sulfoxide and sulfone metabolites. This article is protected by copyright. All rights reserved
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dissipation behavior of Phorate and its toxic metabolites in the sandy clay loam soil of a tropical sugarcane ecosystem using a single step sample preparation method and gc ms
Journal of Separation Science, 2016Co-Authors: Thirumalaiandi Ramasubramanian, M ParamasivamAbstract:The dissipation of Phorate in the sandy clay loam soil of tropical sugarcane ecosystem was studied by employing a single-step sample preparation method and gas chromatography with mass spectrometry. The limit of quantification of the method was 0.01 μg/g. The recoveries of Phorate, Phorate sulfoxide, Phorate sulfone, and Phorate oxon were in the range 94.00-98.46% with relative standard deviations of 1.51-3.56% at three levels of fortification between 0.01 and 0.1 μg/g. The Half-life of Phorate and the total residues, which include Phorate, Phorate sulfoxide and Phorate sulfone, was 5.5 and 19.8 days, respectively at the recommended dose of insecticide. Phorate rapidly oxidized into its sulfoxide metabolite in the sandy clay loam soil. Phorate sulfoxide alone accounted for more than 20% of the total residues within 2 h post-application and it was more than 50% on the fifth day after treatment irrespective of the doses applied. Phorate sulfoxide and Phorate sulfone reached below the detectable level on 105 and 135 days after treatment, respectively as against 45 days after treatment for Phorate residues at the recommended dose. Thus, the reasonably prolonged efficacy of Phorate against soil pests may be attributed to longer persistence of its more toxic sulfoxide and sulfone metabolites.
John P Giesy - One of the best experts on this subject based on the ideXlab platform.
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cytotoxic and necrotic responses in human amniotic epithelial wish cells exposed to organophosphate insecticide Phorate
Mutation Research-genetic Toxicology and Environmental Mutagenesis, 2012Co-Authors: Quaiser Saquib, Maqsood A Siddiqui, Swagata Dasgupta, Javed Musarrat, Sansa Dutta, John P Giesy, Abdulaziz A AlkhedhairyAbstract:a b s t r a c t The in vitro interaction of the organophosphorous insecticide (OPs) Phorate with calf thymus DNA (ctDNA), and its potential to cause changes in cell cycle, membrane damage, and cytotoxicity leading to cell death (necrosis) was investigated in human amnion epithelial (WISH) cells. Fluorescence quench- ing revealed high binding affinity (Ka = 5.62 × 10 4 M −1 ) of Phorate to ctDNA. Molecular modeling of the Phorate-ctDNA interaction suggested the binding of Phorate at AT rich regions on minor groove of DNA. The interaction ensued alkylation of the N-6, N-7 of adenine and C-4 carbonyl oxygen of thymine. Binding of Phorate was stronger in the presence of the transition metal ion copper II (Cu 2+ ), and has accentu- ated the destabilization of the DNA secondary structure. A discernable change in the voltammetric E1/2 (E 0 �
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Phorate induced oxidative stress dna damage and transcriptional activation of p53 and caspase genes in male wistar rats
Toxicology and Applied Pharmacology, 2012Co-Authors: Quaiser Saquib, Abdulaziz A Alkhedhairy, Maqsood A Siddiqui, John P Giesy, Sabry M Attia, Mourad A M Aboulsoud, Javed MusarratAbstract:Male Wistar rats exposed to a systemic organophosphorus insecticide, Phorate [O,O-diethyl S-[(ethylthio) methyl] phosphorothioate] at varying oral doses of 0.046, 0.092 or 0.184mg Phorate/kg bw for 14days, exhibited substantial oxidative stress, cellular DNA damage and activation of apoptosis-related p53, caspase 3 and 9 genes. The histopathological changes including the pyknotic nuclei, inflammatory leukocyte infiltrations, renal necrosis, and cardiac myofiber degeneration were observed in the liver, kidney and heart tissues. Biochemical analysis of catalase and glutathione revealed significantly lesser activities of antioxidative enzymes and lipid peroxidation in tissues of Phorate exposed rats. Furthermore, generation of intracellular reactive oxygen species and reduced mitochondrial membrane potential in bone marrow cells confirmed Phorate-induced oxidative stress. Significant DNA damage was measured through comet assay in terms of the Olive tail moment in bone marrow cells of treated animals as compared to control. Cell cycle analysis also demonstrated the G(2)/M arrest and appearance of a distinctive SubG(1) peak, which signified induction of apoptosis. Up-regulation of tumor suppressor p53 and caspase 3 and 9 genes, determined by quantitative real-time PCR and enzyme-linked immunosorbent assay, elucidated the activation of intrinsic apoptotic pathways in response to cellular stress. Overall, the results suggest that Phorate induces genetic alterations and cellular toxicity, which can adversely affect the normal cellular functioning in rats.
Heping Zhang - One of the best experts on this subject based on the ideXlab platform.
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Screening for Lactobacillus plantarum Strains That Possess Organophosphorus Pesticide-Degrading Activity and Metabolomic Analysis of Phorate Degradation
Frontiers in Microbiology, 2018Co-Authors: Changkun Li, Yuzhu Ma, Zhihui Mi, Yongfu Chen, Lai-yu Kwok, Tingting Zhou, Heping ZhangAbstract:This work performed a large scale assessment for organophosphorus pesticides (OPPs) degradation activity of 121 Lactobacillus (L.) plantarum strains. Six L. plantarum strains (P9, IMAU80110, IMAU40100, IMAU10585, IMAU10209, and IMAU80070) were found to possess high capacity of degrading three commonly used OPPs, namely dimethoate, Phorate, and omethoate; and they were selected for more detailed characterization. Moreover, the three organophosphorus pesticides were mainly detected in the culture supernatants but not in the cell extracts, further confirming that the OPPs were degraded rather than absorbed by the cells. Among the six selected strains, P9 was most tolerant to gastrointestinal juices and bile. We thus used ultra-high performance liquid chromatography electron spray ionization coupled with time-of-flight mass spectrometry (UPLC/ESI-Q-TOF/MS) to generate the metabolomic profiles of the strain P9 growing in MRS medium with and without containing Phorate. By using orthogonal partial least squares discriminant analysis, we identified some potential Phorate-derived degradative products. This work has identified novel lactic acid bacteria resources for application in pesticide degradation. Our results also shed light on the Phorate degradation mechanism by L. plantarum P9.
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Image_2_Screening for Lactobacillus plantarum Strains That Possess Organophosphorus Pesticide-Degrading Activity and Metabolomic Analysis of Phorate Degradation.pdf
2018Co-Authors: Rui Huo, Yongfu Chen, Lai-yu Kwok, Tingting Zhou, Huricha Hai, Zhihong Sun, Heping ZhangAbstract:This work performed a large scale assessment for organophosphorus pesticides (OPPs) degradation activity of 121 Lactobacillus (L.) plantarum strains. Six L. plantarum strains (P9, IMAU80110, IMAU40100, IMAU10585, IMAU10209, and IMAU80070) were found to possess high capacity of degrading three commonly used OPPs, namely dimethoate, Phorate, and omethoate; and they were selected for more detailed characterization. Moreover, the three OPPs were mainly detected in the culture supernatants but not in the cell extracts, further confirming that the OPPs were degraded rather than absorbed by the cells. Among the six selected strains, P9 was most tolerant to gastrointestinal juices and bile. We thus used ultra-high performance liquid chromatography electron spray ionization coupled with time-of-flight mass spectrometry (UPLC/ESI-Q-TOF/MS) to generate the metabolomic profiles of the strain P9 growing in MRS medium with and without containing Phorate. By using orthogonal partial least squares discriminant analysis, we identified some potential Phorate-derived degradative products. This work has identified novel lactic acid bacteria resources for application in pesticide degradation. Our results also shed light on the Phorate degradation mechanism by L. plantarum P9.
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Table_1_Screening for Lactobacillus plantarum Strains That Possess Organophosphorus Pesticide-Degrading Activity and Metabolomic Analysis of Phorate Degradation.docx
2018Co-Authors: Rui Huo, Yongfu Chen, Lai-yu Kwok, Tingting Zhou, Huricha Hai, Zhihong Sun, Heping ZhangAbstract:This work performed a large scale assessment for organophosphorus pesticides (OPPs) degradation activity of 121 Lactobacillus (L.) plantarum strains. Six L. plantarum strains (P9, IMAU80110, IMAU40100, IMAU10585, IMAU10209, and IMAU80070) were found to possess high capacity of degrading three commonly used OPPs, namely dimethoate, Phorate, and omethoate; and they were selected for more detailed characterization. Moreover, the three OPPs were mainly detected in the culture supernatants but not in the cell extracts, further confirming that the OPPs were degraded rather than absorbed by the cells. Among the six selected strains, P9 was most tolerant to gastrointestinal juices and bile. We thus used ultra-high performance liquid chromatography electron spray ionization coupled with time-of-flight mass spectrometry (UPLC/ESI-Q-TOF/MS) to generate the metabolomic profiles of the strain P9 growing in MRS medium with and without containing Phorate. By using orthogonal partial least squares discriminant analysis, we identified some potential Phorate-derived degradative products. This work has identified novel lactic acid bacteria resources for application in pesticide degradation. Our results also shed light on the Phorate degradation mechanism by L. plantarum P9.
Thirumalaiandi Ramasubramanian - One of the best experts on this subject based on the ideXlab platform.
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dissipation behavior of Phorate and its toxic metabolites in the sandy clay loam soil of a tropical sugarcane ecosystem using a single step sample preparation method and gc ms
IEEE Journal of Solid-state Circuits, 2016Co-Authors: Thirumalaiandi Ramasubramanian, M ParamasivamAbstract:The dissipation of Phorate in the sandy clay loam soil of tropical sugarcane ecosystem was studied by employing a single-step sample preparation method and gas chromatography with mass spectrometry. The limit of quantification of the method was 0.01 μg/g. The recoveries of Phorate, Phorate sulfoxide, Phorate sulfone and Phorate oxon were in the range 94.00–98.46% with relative standard deviations of 1.51–3.56% at three levels of fortification between 0.01 and 0.1 μg/g. Half-life of Phorate and the total residues, which include Phorate, Phorate sulfoxide and Phorate sulfone was 5.5 and 19.8 days, respectively at the recommended dose of insecticide. Phorate rapidly oxidized into its sulfoxide metabolite in the sandy clay loam soil. Phorate sulfoxide alone accounted for more than 20% of the total residues within 2 h post-application and it was more than 50% on the fifth day after treatment irrespective of the doses applied. Phorate sulfoxide and Phorate sulfone reached below the detectable level on 105 and 135 days after treatment, respectively as against 45 days after treatment for Phorate residues at the recommended dose. Thus, the reasonably prolonged efficacy of Phorate against soil pests may be attributed to longer persistence of its more toxic sulfoxide and sulfone metabolites. This article is protected by copyright. All rights reserved
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dissipation behavior of Phorate and its toxic metabolites in the sandy clay loam soil of a tropical sugarcane ecosystem using a single step sample preparation method and gc ms
Journal of Separation Science, 2016Co-Authors: Thirumalaiandi Ramasubramanian, M ParamasivamAbstract:The dissipation of Phorate in the sandy clay loam soil of tropical sugarcane ecosystem was studied by employing a single-step sample preparation method and gas chromatography with mass spectrometry. The limit of quantification of the method was 0.01 μg/g. The recoveries of Phorate, Phorate sulfoxide, Phorate sulfone, and Phorate oxon were in the range 94.00-98.46% with relative standard deviations of 1.51-3.56% at three levels of fortification between 0.01 and 0.1 μg/g. The Half-life of Phorate and the total residues, which include Phorate, Phorate sulfoxide and Phorate sulfone, was 5.5 and 19.8 days, respectively at the recommended dose of insecticide. Phorate rapidly oxidized into its sulfoxide metabolite in the sandy clay loam soil. Phorate sulfoxide alone accounted for more than 20% of the total residues within 2 h post-application and it was more than 50% on the fifth day after treatment irrespective of the doses applied. Phorate sulfoxide and Phorate sulfone reached below the detectable level on 105 and 135 days after treatment, respectively as against 45 days after treatment for Phorate residues at the recommended dose. Thus, the reasonably prolonged efficacy of Phorate against soil pests may be attributed to longer persistence of its more toxic sulfoxide and sulfone metabolites.
Javed Musarrat - One of the best experts on this subject based on the ideXlab platform.
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cytotoxic and necrotic responses in human amniotic epithelial wish cells exposed to organophosphate insecticide Phorate
Mutation Research-genetic Toxicology and Environmental Mutagenesis, 2012Co-Authors: Quaiser Saquib, Maqsood A Siddiqui, Swagata Dasgupta, Javed Musarrat, Sansa Dutta, John P Giesy, Abdulaziz A AlkhedhairyAbstract:a b s t r a c t The in vitro interaction of the organophosphorous insecticide (OPs) Phorate with calf thymus DNA (ctDNA), and its potential to cause changes in cell cycle, membrane damage, and cytotoxicity leading to cell death (necrosis) was investigated in human amnion epithelial (WISH) cells. Fluorescence quench- ing revealed high binding affinity (Ka = 5.62 × 10 4 M −1 ) of Phorate to ctDNA. Molecular modeling of the Phorate-ctDNA interaction suggested the binding of Phorate at AT rich regions on minor groove of DNA. The interaction ensued alkylation of the N-6, N-7 of adenine and C-4 carbonyl oxygen of thymine. Binding of Phorate was stronger in the presence of the transition metal ion copper II (Cu 2+ ), and has accentu- ated the destabilization of the DNA secondary structure. A discernable change in the voltammetric E1/2 (E 0 �
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Phorate induced oxidative stress dna damage and transcriptional activation of p53 and caspase genes in male wistar rats
Toxicology and Applied Pharmacology, 2012Co-Authors: Quaiser Saquib, Abdulaziz A Alkhedhairy, Maqsood A Siddiqui, John P Giesy, Sabry M Attia, Mourad A M Aboulsoud, Javed MusarratAbstract:Male Wistar rats exposed to a systemic organophosphorus insecticide, Phorate [O,O-diethyl S-[(ethylthio) methyl] phosphorothioate] at varying oral doses of 0.046, 0.092 or 0.184mg Phorate/kg bw for 14days, exhibited substantial oxidative stress, cellular DNA damage and activation of apoptosis-related p53, caspase 3 and 9 genes. The histopathological changes including the pyknotic nuclei, inflammatory leukocyte infiltrations, renal necrosis, and cardiac myofiber degeneration were observed in the liver, kidney and heart tissues. Biochemical analysis of catalase and glutathione revealed significantly lesser activities of antioxidative enzymes and lipid peroxidation in tissues of Phorate exposed rats. Furthermore, generation of intracellular reactive oxygen species and reduced mitochondrial membrane potential in bone marrow cells confirmed Phorate-induced oxidative stress. Significant DNA damage was measured through comet assay in terms of the Olive tail moment in bone marrow cells of treated animals as compared to control. Cell cycle analysis also demonstrated the G(2)/M arrest and appearance of a distinctive SubG(1) peak, which signified induction of apoptosis. Up-regulation of tumor suppressor p53 and caspase 3 and 9 genes, determined by quantitative real-time PCR and enzyme-linked immunosorbent assay, elucidated the activation of intrinsic apoptotic pathways in response to cellular stress. Overall, the results suggest that Phorate induces genetic alterations and cellular toxicity, which can adversely affect the normal cellular functioning in rats.
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preferential binding of insecticide Phorate with sub domain iia of human serum albumin induces protein damage and its toxicological significance
Food and Chemical Toxicology, 2011Co-Authors: Quaiser Saquib, Abdulaziz A Alkhedhairy, Maqsood A Siddiqui, Atanu Singha Roy, Swagata Dasgupta, Javed MusarratAbstract:Abstract Phorate, an organophosphorus insecticide is known for its adverse effects on acetylcholinesterase, and other neuronal and pulmonary activities. Most likely, the toxicity of drugs/agrochemicals is modulated through cellular distribution bound to plasma proteins. Therefore, the in vitro interaction of Phorate with human serum albumin (HSA) has been investigated, using sensitive techniques like fluorescence spectroscopy and circular dichroism, to ascertain its binding mechanism and toxicological implications. Fluorescence studies revealed the quenching constant (Ksv) as 2.5 × 10 4 M −1 and binding affinity (Ka) as 2.96 × 10 4 M −1 ( r 2 = 0.99), with a primary binding site of Phorate at sub-domain IIA of HSA. Circular dichroism (CD) data demonstrated a noticeable reduction in secondary structure (α-helical content) of Phorate treated HSA. Albumin treated with 200–1000 μM Phorate released significant amounts of acid soluble amino and carbonyl groups, whereas higher concentrations resulted in protein fragmentation. It is postulated that the 1′-O and 3-O alkyl groups of Phorate have a role in binding with electrophilic centers of Trp 214, and Arg 218/Lys 195, respectively. Moreover, the significant ultrastructural changes, reactive oxygen species (ROS) generation, mitochondrial damage and cell death in Phorate treated cultured human amnion epithelial (WISH) cells, elucidated Phorate induced cellular toxicity.