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Dhiraj Sud - One of the best experts on this subject based on the ideXlab platform.
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Persistence and Biodegradation of Quinalphos Using Soil Microbes
Water Environment Research, 2014Co-Authors: Noorpreet Inder Kaur Dhanjal, Dhiraj Sud, Paramjeet Kaur, Swaranjit Singh CameotraAbstract:The present study reports the degradation of the persistent and toxic organophosphate, Quinalphos, by employing microorganisms that were already members of the natural soil community for degradation. Bacillus and Pseudomonas spp., both of which are capable of degrading Quinalphos from aqueous streams, were isolated from different contaminated soils. Batch experiments were performed to determine the natural and induced biodegradation of Quinalphos in the aqueous medium. The rate of degradation was analyzed through determination of residual concentration using UV-Vis spectrophotometer and high-performance liquid chromatography. A single peak of a metabolite was observed on the 160th day, and identified as dihydroxy Quinalphos oxon by mass spectrometry. The presence of Quinalphos and its metabolite in water over an extended period prompted the authors to investigate its induced biodegradation using indigenous microbes extracted from soil. For biodegradation studies, the isolated microbes were inoculated into minimal media with Quinalphos for 17 days. The results revealed that >80% of Quinalphos was degraded in 17 days in the presence of isolated microbes, and no metabolite was observed during the biodegradation process.
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photocatalytic degradation of Quinalphos in aqueous tio2 suspension reaction pathway and identification of intermediates by gc ms
Journal of Molecular Catalysis A-chemical, 2012Co-Authors: Paramjeet Kaur, Dhiraj SudAbstract:Abstract Quinalphos is one of the widely used organophosphate pesticides and known for its persistence in water. The present study investigates the TiO 2 mediated photocatalytic degradation of Quinalphos. The rate constant for degradation of Quinalphos were calculated to be 0.00567 min −1 and higher degradation rate was observed with 1.5 g/L concentration of TiO 2 and at pH 8. The feasible intermediates formed during the photocatalytic treatment were identified by using analytical techniques such as UV–vis spectrophotometry, gas chromatography–mass spectrometry (GC–MS) and ion chromatography (IC). Seven possible intermediates were identified and the formation of initial intermediates involve photooxidation of P S to P O (Quinalphos-oxon), attack by hydroxyl group on quinoxaline ring and dealkylation of the phosphate moiety. The complete degradation of Quinalphos has been obtained in 24 h, as no peaks have been observed in a gas chromatogram. The aliphatic acid ions, SO 4 2− , NO 3 − and PO 4 3− were identified by IC. Based on identified products, the mechanism of the photocatalytic degradation was proposed.
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Photocatalytic degradation of Quinalphos in aqueous TiO2 suspension: Reaction pathway and identification of intermediates by GC/MS
Journal of Molecular Catalysis A: Chemical, 2012Co-Authors: Paramjeet Kaur, Dhiraj SudAbstract:Abstract Quinalphos is one of the widely used organophosphate pesticides and known for its persistence in water. The present study investigates the TiO 2 mediated photocatalytic degradation of Quinalphos. The rate constant for degradation of Quinalphos were calculated to be 0.00567 min −1 and higher degradation rate was observed with 1.5 g/L concentration of TiO 2 and at pH 8. The feasible intermediates formed during the photocatalytic treatment were identified by using analytical techniques such as UV–vis spectrophotometry, gas chromatography–mass spectrometry (GC–MS) and ion chromatography (IC). Seven possible intermediates were identified and the formation of initial intermediates involve photooxidation of P S to P O (Quinalphos-oxon), attack by hydroxyl group on quinoxaline ring and dealkylation of the phosphate moiety. The complete degradation of Quinalphos has been obtained in 24 h, as no peaks have been observed in a gas chromatogram. The aliphatic acid ions, SO 4 2− , NO 3 − and PO 4 3− were identified by IC. Based on identified products, the mechanism of the photocatalytic degradation was proposed.
Priyanka Sharma - One of the best experts on this subject based on the ideXlab platform.
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Maximum contaminant level of arsenic in drinking water potentiates Quinalphos-induced renal damage on co-administration of both arsenic and Quinalphos in Wistar rats
Environmental Science and Pollution Research, 2020Co-Authors: Parvinder Singh, Pawan Kumar Verma, Rajinder Raina, Shilpa Sood, Priyanka SharmaAbstract:This study was designed to determine alterations in renal biomarkers, antioxidant profile, and histomorphology of renal tissue following subacute exposure to Quinalphos alone or in conjunction with arsenic in rats. A total of 54 adult Wistar rats were randomly divided into nine groups of six rats each and were administered sub-lethal concentrations of Quinalphos (1/100^th and 1/10^th of LD_50) orally daily and arsenic (50 and 100 ppb) in drinking water for 28 days. Significantly ( p
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Maximum contaminant level of arsenic in drinking water potentiates Quinalphos-induced renal damage on co-administration of both arsenic and Quinalphos in Wistar rats.
Environmental Science and Pollution Research, 2020Co-Authors: Parvinder Pal Singh, Pawan Kumar Verma, Rajinder Raina, Shilpa Sood, Priyanka SharmaAbstract:This study was designed to determine alterations in renal biomarkers, antioxidant profile, and histomorphology of renal tissue following subacute exposure to Quinalphos alone or in conjunction with arsenic in rats. A total of 54 adult Wistar rats were randomly divided into nine groups of six rats each and were administered sub-lethal concentrations of Quinalphos (1/100th and 1/10th of LD50) orally daily and arsenic (50 and 100 ppb) in drinking water for 28 days. Significantly (p < 0.05) decreased levels of antioxidant biomarkers in renal tissue, viz., total thiols, catalase, superoxide dismutase, glutathione peroxidase, glutathione-s-transferase, and glutathione reductase along with increased (p < 0.05) thiobarbituric acid reacting substance (TBRAS) levels indicated that significant oxidative damage to renal tissue occurred following repeated administrations of Quinalphos at either dose levels or arsenic at the concentration of 100 ppb when compared with the control rats. The alterations in the antioxidant parameters were observed to be more pronounced in co-administered groups as compared with either toxicant administered group. Similarly, activity of renal acetylcholinesterase was decreased after repeated exposure to Quinalphos or arsenic, but inhibition was higher (up to 48%) in rat renal tissue co-exposed with Quinalphos and arsenic at the higher concentration. These findings corroborated with the histopathological alterations in renal tissue of toxicant exposed rats. The altered plasma and tissue antioxidant biomarkers along with histopathological changes in the kidney at higher dose level of either toxicant indicate that renal tissue is significantly impacted by these toxicants, and these effects become more pronounced after their co-administration.
Paramjeet Kaur - One of the best experts on this subject based on the ideXlab platform.
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Persistence and Biodegradation of Quinalphos Using Soil Microbes
Water Environment Research, 2014Co-Authors: Noorpreet Inder Kaur Dhanjal, Dhiraj Sud, Paramjeet Kaur, Swaranjit Singh CameotraAbstract:The present study reports the degradation of the persistent and toxic organophosphate, Quinalphos, by employing microorganisms that were already members of the natural soil community for degradation. Bacillus and Pseudomonas spp., both of which are capable of degrading Quinalphos from aqueous streams, were isolated from different contaminated soils. Batch experiments were performed to determine the natural and induced biodegradation of Quinalphos in the aqueous medium. The rate of degradation was analyzed through determination of residual concentration using UV-Vis spectrophotometer and high-performance liquid chromatography. A single peak of a metabolite was observed on the 160th day, and identified as dihydroxy Quinalphos oxon by mass spectrometry. The presence of Quinalphos and its metabolite in water over an extended period prompted the authors to investigate its induced biodegradation using indigenous microbes extracted from soil. For biodegradation studies, the isolated microbes were inoculated into minimal media with Quinalphos for 17 days. The results revealed that >80% of Quinalphos was degraded in 17 days in the presence of isolated microbes, and no metabolite was observed during the biodegradation process.
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photocatalytic degradation of Quinalphos in aqueous tio2 suspension reaction pathway and identification of intermediates by gc ms
Journal of Molecular Catalysis A-chemical, 2012Co-Authors: Paramjeet Kaur, Dhiraj SudAbstract:Abstract Quinalphos is one of the widely used organophosphate pesticides and known for its persistence in water. The present study investigates the TiO 2 mediated photocatalytic degradation of Quinalphos. The rate constant for degradation of Quinalphos were calculated to be 0.00567 min −1 and higher degradation rate was observed with 1.5 g/L concentration of TiO 2 and at pH 8. The feasible intermediates formed during the photocatalytic treatment were identified by using analytical techniques such as UV–vis spectrophotometry, gas chromatography–mass spectrometry (GC–MS) and ion chromatography (IC). Seven possible intermediates were identified and the formation of initial intermediates involve photooxidation of P S to P O (Quinalphos-oxon), attack by hydroxyl group on quinoxaline ring and dealkylation of the phosphate moiety. The complete degradation of Quinalphos has been obtained in 24 h, as no peaks have been observed in a gas chromatogram. The aliphatic acid ions, SO 4 2− , NO 3 − and PO 4 3− were identified by IC. Based on identified products, the mechanism of the photocatalytic degradation was proposed.
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Photocatalytic degradation of Quinalphos in aqueous TiO2 suspension: Reaction pathway and identification of intermediates by GC/MS
Journal of Molecular Catalysis A: Chemical, 2012Co-Authors: Paramjeet Kaur, Dhiraj SudAbstract:Abstract Quinalphos is one of the widely used organophosphate pesticides and known for its persistence in water. The present study investigates the TiO 2 mediated photocatalytic degradation of Quinalphos. The rate constant for degradation of Quinalphos were calculated to be 0.00567 min −1 and higher degradation rate was observed with 1.5 g/L concentration of TiO 2 and at pH 8. The feasible intermediates formed during the photocatalytic treatment were identified by using analytical techniques such as UV–vis spectrophotometry, gas chromatography–mass spectrometry (GC–MS) and ion chromatography (IC). Seven possible intermediates were identified and the formation of initial intermediates involve photooxidation of P S to P O (Quinalphos-oxon), attack by hydroxyl group on quinoxaline ring and dealkylation of the phosphate moiety. The complete degradation of Quinalphos has been obtained in 24 h, as no peaks have been observed in a gas chromatogram. The aliphatic acid ions, SO 4 2− , NO 3 − and PO 4 3− were identified by IC. Based on identified products, the mechanism of the photocatalytic degradation was proposed.
Parvinder Singh - One of the best experts on this subject based on the ideXlab platform.
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Maximum contaminant level of arsenic in drinking water potentiates Quinalphos-induced renal damage on co-administration of both arsenic and Quinalphos in Wistar rats
Environmental Science and Pollution Research, 2020Co-Authors: Parvinder Singh, Pawan Kumar Verma, Rajinder Raina, Shilpa Sood, Priyanka SharmaAbstract:This study was designed to determine alterations in renal biomarkers, antioxidant profile, and histomorphology of renal tissue following subacute exposure to Quinalphos alone or in conjunction with arsenic in rats. A total of 54 adult Wistar rats were randomly divided into nine groups of six rats each and were administered sub-lethal concentrations of Quinalphos (1/100^th and 1/10^th of LD_50) orally daily and arsenic (50 and 100 ppb) in drinking water for 28 days. Significantly ( p
Rajinder Raina - One of the best experts on this subject based on the ideXlab platform.
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Maximum contaminant level of arsenic in drinking water potentiates Quinalphos-induced renal damage on co-administration of both arsenic and Quinalphos in Wistar rats
Environmental Science and Pollution Research, 2020Co-Authors: Parvinder Singh, Pawan Kumar Verma, Rajinder Raina, Shilpa Sood, Priyanka SharmaAbstract:This study was designed to determine alterations in renal biomarkers, antioxidant profile, and histomorphology of renal tissue following subacute exposure to Quinalphos alone or in conjunction with arsenic in rats. A total of 54 adult Wistar rats were randomly divided into nine groups of six rats each and were administered sub-lethal concentrations of Quinalphos (1/100^th and 1/10^th of LD_50) orally daily and arsenic (50 and 100 ppb) in drinking water for 28 days. Significantly ( p
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Maximum contaminant level of arsenic in drinking water potentiates Quinalphos-induced renal damage on co-administration of both arsenic and Quinalphos in Wistar rats.
Environmental Science and Pollution Research, 2020Co-Authors: Parvinder Pal Singh, Pawan Kumar Verma, Rajinder Raina, Shilpa Sood, Priyanka SharmaAbstract:This study was designed to determine alterations in renal biomarkers, antioxidant profile, and histomorphology of renal tissue following subacute exposure to Quinalphos alone or in conjunction with arsenic in rats. A total of 54 adult Wistar rats were randomly divided into nine groups of six rats each and were administered sub-lethal concentrations of Quinalphos (1/100th and 1/10th of LD50) orally daily and arsenic (50 and 100 ppb) in drinking water for 28 days. Significantly (p < 0.05) decreased levels of antioxidant biomarkers in renal tissue, viz., total thiols, catalase, superoxide dismutase, glutathione peroxidase, glutathione-s-transferase, and glutathione reductase along with increased (p < 0.05) thiobarbituric acid reacting substance (TBRAS) levels indicated that significant oxidative damage to renal tissue occurred following repeated administrations of Quinalphos at either dose levels or arsenic at the concentration of 100 ppb when compared with the control rats. The alterations in the antioxidant parameters were observed to be more pronounced in co-administered groups as compared with either toxicant administered group. Similarly, activity of renal acetylcholinesterase was decreased after repeated exposure to Quinalphos or arsenic, but inhibition was higher (up to 48%) in rat renal tissue co-exposed with Quinalphos and arsenic at the higher concentration. These findings corroborated with the histopathological alterations in renal tissue of toxicant exposed rats. The altered plasma and tissue antioxidant biomarkers along with histopathological changes in the kidney at higher dose level of either toxicant indicate that renal tissue is significantly impacted by these toxicants, and these effects become more pronounced after their co-administration.
