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Journal of Basic Microbiology Mar 2022Phorate is a systemic insecticide used to eradicate mites, insects, and nematodes. Extensive use of this organophosphate has engendered severe environmental concerns....
Phorate is a systemic insecticide used to eradicate mites, insects, and nematodes. Extensive use of this organophosphate has engendered severe environmental concerns. The current research aimed to explore the kinetic pathways of phorate biodegradation in aqueous solutions. Two novel bacterial strains Pseudomonas aeruginosa strain PR1 (KP268772.1) and Pseudomonas sp. PR_02 (KP268773.1) were isolated, screened, and developed given their potential to degrade phorate. Mineralization of phorate was assayed with and without the addition of metal ions [Fe (II) and Cu (II)] and humic acid (HA). In 14 days, experiment both strains have consumed about 69%-94.5% (half-life from 3.58 to 6.02 days) of phorate. The observed biodegradation rate of phorate with Cu (II) in the system was 73% and 87%, with a half-life of 4.86 and 4.07 days for PR1 and PR2, respectively. The biodegradation of phorate using Fe(II) was 69% and 82%, with half-life periods 5.68 and 4.49 days. Meanwhile, incorporating HA, the phorate biodegradation was inhibited significantly, showing 71% and 85% degradation, with half-life periods of 6.02 and 5.02 days. The results indicated that both bacterial strains were able to mineralize phorate with PR2 > PR1. Summarizing, the inhibition in phorate biodegradation order under different conditions was as HA > Fe (II) > Cu (II). UV-visible measurements and gas chromatography-mass spectrometric assays indicated that the possible degradation pathway of phorate included ethoxy-phosphonothio-methanethiol S-mercaptomethyl-O,O-dihydrogen phosphorodithioate, diethyl-methylphosphonate, methane dithiol, ethanethiol, and phosphate, as the main metabolites identified. Therefore, it was concluded that the newly isolated Pseudomonas strains could be a potential candidates for biodegradation of phorate in a cost-effective, safe, and environmentally friendly alternative.
Topics: Bacteria; Biodegradation, Environmental; Humic Substances; Phorate; Soil Microbiology
PubMed: 34520071
DOI: 10.1002/jobm.202100332 -
Saudi Journal of Biological Sciences Nov 2019Herein, we studied phorate for its toxicological effects in human lymphocytes. Phorate treatment for 3 h has induced significant increase in the lymphocytic DNA...
Herein, we studied phorate for its toxicological effects in human lymphocytes. Phorate treatment for 3 h has induced significant increase in the lymphocytic DNA damage. Compared to control, comet data from highest concentration of phorate (1000 µM) showed 8.03-fold increase in the Olive tail moment (OTM). Cytokinesis blocked micronucleus (CBMN) assay revealed 6.4-fold increase in binucleated micronucleated (BNMN) cells following the exposure with phorate (200 µM) for 24 h. The nuclear division index (NDI) in phorate (200 µM) treated cells reduced to 1.8 vis-à-vis control cells showed NDI of 1.94. Comparative to untreated control, 60.43% greater DCF fluorescence was quantitated in lymphocytes treated with phorate (500 µM), affirming reactive oxygen species (ROS) generation and oxidative stress. Flow cytometric data of phorate (200 µM) treated lymphocytes showed 81.77% decline in the fluorescence of rhodamine 123 (Rh123) dye, confirming the perturbation of mitochondrial membrane potential (Δ). Calf thymus DNA (ct-DNA) treated with phorate (1000 µM) exhibited 2.3-fold higher 8-Hydroxy-2'-deoxyguanosine (8-oxodG) DNA adduct formation, signified the oxidative DNA damage. The alkaline unwinding assay revealed 4.0 and 6.5 ct-DNA strand breaks when treated to phorate and phorate-Cu (II) complex. Overall, the data unequivocally suggests the cyto- and genotoxic potential of phorate in human lymphocytes, which may induce comparable toxicological consequences in persons occupationally or non-occupationally exposed to insecticide phorate.
PubMed: 31762602
DOI: 10.1016/j.sjbs.2019.04.008 -
Antibiotics (Basel, Switzerland) Nov 2022Phorate is a systemic, broad-spectrum organophosphorus insecticide. Although it is commonly used worldwide, phorate, like other pesticides, not only causes environmental...
Phorate is a systemic, broad-spectrum organophosphorus insecticide. Although it is commonly used worldwide, phorate, like other pesticides, not only causes environmental pollution but also poses serious threats to human and animal health. Herein, we measured the blood glucose concentrations of high-fat-diet-fed mice exposed to various concentrations of phorate (0, 0.005, 0.05, or 0.5 mg/kg); we also assessed the blood glucose concentrations of high-fat-diet-fed mice exposed to phorate; we also assessed the distribution characteristics of the resistance genes in the intestinal microbiota of these mice. We found that 0.005 and 0.5 mg/kg of phorate induced obvious hyperglycaemia in the high-fat-diet-fed mice. Exposure to phorate markedly reduced the abundance of in the mouse intestine. The resistance genes , and were significantly upregulated in the test group compared with the control group. Efflux pumping was the primary mechanism of drug resistance in the , and found in the mouse intestine. Our findings indicate that changes in the abundance of the intestinal microbiota are closely related to the presence of antibiotic-resistant bacteria in the intestinal tract and the metabolic health of the host.
PubMed: 36358236
DOI: 10.3390/antibiotics11111584 -
Toxics Apr 2022It has been estimated that approximately one in seven of all global suicides is due to pesticide self-poisoning, mostly in rural areas of developing countries....
It has been estimated that approximately one in seven of all global suicides is due to pesticide self-poisoning, mostly in rural areas of developing countries. Organophosphorus (OP) compounds are a group of pesticides exerting their toxicological effects through non-reversible inhibition of the enzyme acetylcholinesterase (AChE). Among these compounds, phorate (thimet) is one of the most dangerous compounds, the use of which is restricted in many countries. A case of intentional suicide after phorate ingestion in a 24-year-old Bengali male is described. This is the second case of suicidal ingestion of phorate reported in the forensic literature, and the first presenting complete toxicological findings.
PubMed: 35622619
DOI: 10.3390/toxics10050205 -
Pest Management Science Feb 2017Organophosphate insecticides can inhibit specific cytochrome P450 enzymes involved in metabolic herbicide resistance mechanisms, leading to synergistic interactions...
BACKGROUND
Organophosphate insecticides can inhibit specific cytochrome P450 enzymes involved in metabolic herbicide resistance mechanisms, leading to synergistic interactions between the insecticide and the herbicide. In this study we report synergistic versus antagonistic interactions between the organophosphate insecticide phorate and five different herbicides observed in a population of multiple herbicide-resistant Lolium rigidum.
RESULTS
Phorate synergised with three different herbicide modes of action, enhancing the activity of the ALS inhibitor chlorsulfuron (60% LD reduction), the VLCFAE inhibitor pyroxasulfone (45% LD reduction) and the mitosis inhibitor trifluralin (70% LD reduction). Conversely, phorate antagonised the two thiocarbamate herbicides prosulfocarb and triallate with a 12-fold LD increase.
CONCLUSION
We report the selective reversal of P450-mediated metabolic multiple resistance to chlorsulfuron and trifluralin in the grass weed L. rigidum by synergistic interaction with the insecticide phorate, and discuss the putative mechanistic basis. This research should encourage diversity in herbicide use patterns for weed control as part of a long-term integrated management effort to reduce the risk of selection of metabolism-based multiple herbicide resistance in L. rigidum. © 2016 Society of Chemical Industry.
Topics: Cholinesterase Inhibitors; Cytochrome P-450 Enzyme System; Herbicide Resistance; Herbicides; Insecticides; Lolium; Pesticide Synergists; Phorate
PubMed: 27643926
DOI: 10.1002/ps.4441 -
Ecotoxicology and Environmental Safety Sep 2018Microbial consortia isolated from aged phorate contaminated soil were used to degrade phorate. The consortia of three microorganisms (Brevibacterium frigoritolerans,...
Microbial consortia isolated from aged phorate contaminated soil were used to degrade phorate. The consortia of three microorganisms (Brevibacterium frigoritolerans, Bacillus aerophilus and Pseudomonas fulva) could degrade phorate, and the highest phorate removal (between 97.65 and 98.31%) was found in soils inoculated with mixed cultures of all the three bacterial species. However, the mixed activity of any of two of these bacteria was lower than mixed consortia of all the three bacterial species. The highest degradation by individual mixed consortia of (B. frigoritolerans+B.aerophilus, B. aerophilus+P. fulva and B. frigoritolerans+P. fulva) appeared in soil between (92.28-94.09%, 95.45-97.15% and 94.08-97.42%, respectively). Therefore, inoculation of highly potential microbial consortia isolated from in situ contaminated soil could result in most effective bioremediation consortia for significantly relieving soils from phorate residues. This much high phorate remediation from phorate contaminated soils have never been reported earlier by mixed culture of native soil bacterial isolates.
Topics: Bacillus; Biodegradation, Environmental; Insecticides; Microbial Consortia; Phorate; Pseudomonas; Soil Microbiology; Soil Pollutants
PubMed: 29772463
DOI: 10.1016/j.ecoenv.2018.04.063 -
Journal of Separation Science Oct 2016The 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...
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.
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.
Topics: Aluminum Silicates; Clay; Ecosystem; Gas Chromatography-Mass Spectrometry; Half-Life; Insecticides; Pesticide Residues; Phorate; Saccharum; Soil; Soil Pollutants
PubMed: 27546010
DOI: 10.1002/jssc.201600560 -
Environmental Science and Pollution... Feb 2014Based upon 16S rDNA sequence homology, 15 phorate-degrading bacteria isolated from sugarcane field soils by selective enrichment were identified to be different species...
Based upon 16S rDNA sequence homology, 15 phorate-degrading bacteria isolated from sugarcane field soils by selective enrichment were identified to be different species of Bacillus, Pseudomonas, Brevibacterium, and Staphylococcus. Relative phorate degradation in a mineral salt medium containing phorate (50 μg ml(-1)) as sole carbon source established that all the bacterial species could actively degrade more than 97 % phorate during 21 days. Three of these species viz. Bacillus aerophilus strain IMBL 4.1, Brevibacterium frigoritolerans strain IMBL 2.1, and Pseudomonas fulva strain IMBL 5.1 were found to be most active phorate metabolizers, degrading more than 96 % phorate during 2 days and 100 % phorate during 13 days. Qualitative analysis of phorate residues by gas liquid chromatography revealed complete metabolization of phorate without detectable accumulation of any known phorate metabolites. Phorate degradation by these bacterial species did not follow the first-order kinetics except the P. fulva strain IMBL 5.1 with half-life period (t1/2) ranging between 0.40 and 5.47 days.
Topics: Agriculture; Bacteria; Half-Life; Phorate; Soil; Soil Microbiology; Soil Pollutants
PubMed: 24046230
DOI: 10.1007/s11356-013-2155-2 -
Brain Research Bulletin 1997The organophosphate pesticide, phorate, is an extremely hazardous insecticide. Not much experimental study is available on effects of phorate on different brain areas....
The organophosphate pesticide, phorate, is an extremely hazardous insecticide. Not much experimental study is available on effects of phorate on different brain areas. We report in this study the alterations induced by phorate on enzyme profile of mouse olfactory bulb. Olfactory bulb, the first processing centre after the sensory cells in the olfactory pathway, has connections with the other higher centres of the brain like hippocampus and hypothalamus. Phorate was administered orally in the diet at the doses of 1.0 mg and 1.5 mg/kg body weight to adult albino mice. After 32 weeks of exposure animals were sacrificed and cryosections were processed for acetylcholinesterase and butyrylcholinesterase (AChE and BChE, respectively) enzyme localization. Significant reduction occurs in AChE and BChE activity at higher dose level, whereas reduced BChE activity was found at both dose levels. Our results shows an obvious effect on cholinesterase enzyme profile of olfactory bulb of mice after systemic administration of low doses of phorate for long terms.
Topics: Acetylcholinesterase; Animals; Behavior, Animal; Butyrylcholinesterase; Cholinesterase Inhibitors; Defecation; Endothelium, Vascular; Male; Mice; Nerve Fibers; Neurons; Olfactory Bulb; Phorate; Urination
PubMed: 9323438
DOI: 10.1016/s0361-9230(97)00116-0 -
Chemosphere Sep 2017The present study was conducted to assess the in-vivo activities of certain molecular biomarkers under the impact of phorate exposure. Fish, Channa punctatus...
The present study was conducted to assess the in-vivo activities of certain molecular biomarkers under the impact of phorate exposure. Fish, Channa punctatus (35 ± 3.0 g; 14.5 ± 1.0 cm; Actinopterygii) were subjected to semi-static conditions having 5% (0.0375 mg/L for T1 group) and 10% of 96 h-LC (0.075 mg/L for T2 group) of phorate exposure for 15 and 30 d. The oxidative stress was assessed in terms of superoxide dismutase (SOD) and catalase (CAT) activities. DNA damage was measured as induction of micronuclei (MN) and consequent differential expression of apoptotic genes-tumor suppressor (p53), apoptotic peptidase activating factor-1 (apaf-1) and catalase (cat) in liver and kidney, two major sites of biotransformation in fish, were quantified. Our findings reveal significant (p < 0.001) augmentations in SOD and CAT activities of liver and kidney tissues. MN frequency in erythrocytes of fish also increases significantly (p < 0.05) in a dose- and time-dependent manner. The mRNA level of p53 increased significantly (p < 0.05) in liver at 10% of 96 h-LC of phorate exposure after 30 d suggesting generation of stress due to accumulation of reactive oxygen species (ROS). Eventually, these findings decipher the dual role of ROS in generating genotoxicity as is evident by micronuclei induction and differential regulation of p53, apaf-1 and cat genes during the phorate induced DNA damage and apoptosis in test fish. The experimental inferences drawn on the basis of activities of aforesaid biomarkers shall be helpful in elucidating the possible causes of apoptosis under stressful conditions. Further, this study finds ample application in biomonitoring of phorate polluted aquatic ecosystem.
Topics: Animals; Apoptotic Protease-Activating Factor 1; Catalase; Cholinesterase Inhibitors; DNA Damage; Fishes; Gene Expression Profiling; Kidney; Liver; Oxidative Stress; Perciformes; Phorate; Superoxide Dismutase; Tumor Suppressor Protein p53
PubMed: 28511133
DOI: 10.1016/j.chemosphere.2017.05.008