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1.
Chemosphere ; 283: 131304, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34467944

RESUMO

Herbicides are commonly used globally. However, residual herbicides in soils for ages often result in phytotoxicity and serious yield loss to subsequent crops. In this paper, the multi-walled carbon nanotubes (MWCNTs) were utilized to amend the herbicide polluted soil, and the adsorption performance of herbicides to MWCNTs amended soil was studied. Results indicate efficient alleviation of herbicide-induced phytotoxicity to rice and tobacco due to MWCNTs amendment. When 0.4% MWCNTs were applied, the concentration of sulfentrazone that inhibited the same rice height by 50% (IC50) increased to more than 3 times that of pure soil. When the MWCNTs were used to alleviate the phytotoxicity of quinclorac to tobacco, the MWCNTs not only alleviated the phytotoxicity of quinclorac but also promoted the growth of tobacco. The MWCNTs amended soil significantly increased the adsorption of herbicide to soil than biochar. The soil microbial analysis shows that MWCNTs had no significant effect on soil microbial community diversity, but the long-term exposure to MWCNTs could change the structure of the soil microbial community. Above all, our results highlighted the potential implication of the MWCNTs to ensure crop production by promoting crop growth and reducing the residual bioavailability of herbicides.


Assuntos
Herbicidas , Nanotubos de Carbono , Poluentes do Solo , Adsorção , Herbicidas/análise , Herbicidas/toxicidade , Nanotubos de Carbono/toxicidade , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
2.
J Environ Manage ; 297: 113427, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34346399

RESUMO

The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) is widely used due to it selective action, and preferential control of dicotyledonous weeds affecting cereal crops. Physiological responses of sensitive dicotyledonous plants to 2,4-D include growth retardation, senescence, and cell death. Due to soil and water contamination by agricultural practices, 2,4-D constitutes a potential risk to non-target plant species. In this work, the potential advantage of using organic modified bentonite (Bent) to adsorb 2,4-D and therefore mitigate damage produced by this herbicide on sensitive not-target vegetable species was investigated. Dodecylamine (DDA) was used as an organic modifier to change the hydrophilic nature of Bent into an organophilic matrix. The adsorption performances of 2,4-D by Bent-DDA were analyzed. The maximum adsorptions of 2,4-D (22.1 mg/L) from aqueous solution containing 1.0 or 2.5 mg/mL Bent-DDA were 40 and 80 %, respectively. The physical interaction of Bent-DDA with 2,4-D was characterized by Wide Angle X-ray Scattering (WAXS) and thermogravimetric analysis (TGA). The biological functionality of Bent-DDA matrix as 2,4-D adsorbent was tested in a bioassay in the Arabidopsis thaliana plant model system. The primary root growth of Arabidopsis seedlings is strongly inhibited by low concentrations of 2,4-D. Arabidopsis seedlings submitted to Bent-DDA pre-treated herbicide aqueous solution showed similar root growth than 2,4-D non-treated seedlings. Finally, the ability of Bent-DDA to prevent 2,4-D phytotoxicity was exploratory investigated in lettuce plants. Lettuce plants pre-treated with 20 µg/mL Bent-DDA showed reduced sensitivity to 2,4-D including an increment on chlorophyll content and biomass compared with non-treated plants. Our findings revealed a promising scenario for the application of Bent-DDA as an effective adsorbent of 2,4-D at productive scale.


Assuntos
Bentonita , Herbicidas , Ácido 2,4-Diclorofenoxiacético/toxicidade , Herbicidas/toxicidade , Plantas Daninhas , Plântula
3.
Pestic Biochem Physiol ; 178: 104918, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34446194

RESUMO

Herbicide resistance is frequently reported in E. crus-galli globally with target and non-target site resistance mechanism to acetolactate synthase (ALS)-inhibiting herbicides. However, resistance to certain herbicides can result in increased sensitivity to other herbicides, a phenomenon called negative cross-resistance. The objective of this study is to identify the occurrence of negative cross-resistance (NCR) to the pro-herbicide clomazone in populations of E. crus-galli resistant to ALS inhibitors due to increased metabolization. Clomazone dose-response curves, with and without malathion, were performed in imazethapyr-resistant and -susceptible E. crus-galli biotypes. CYPs genes expression and antioxidant enzymes activity were also evaluated. The effective dose to reduce 50% (ED50) of dry shoot weight obtained in the clomazone dose-response curves of the metabolic based imazethapyr-resistant and -susceptible biotypes groups were 22.712 and 58.745 g ha-1, respectively, resulting in a resistance factor (RF) of 0.37, indicating the occurrence of NCR. The application of malathion prior to clomazone increased the resistance factor from 0.60 to 1.05, which indicate the reversion of the NCR. Some CYP genes evaluated were expressed in a higher level, ranging from 2.6-9.1 times according to the biotype and the gene, in the imazethapyr-resistant than in -susceptible biotypes following clomazone application. Antioxidant enzyme activity was not associated with NCR. This study is the first report of NCR directly related to the mechanism of resistance increased metabolization in plants. The occurrence of NCR to clomazone in E. crus-galli can help delay the evolution of herbicide resistance.


Assuntos
Acetolactato Sintase , Echinochloa , Herbicidas , Ácidos Nicotínicos , Acetolactato Sintase/genética , Echinochloa/genética , Resistência a Herbicidas/genética , Herbicidas/toxicidade , Isoxazóis , Ácidos Nicotínicos/toxicidade , Oxazolidinonas
4.
Molecules ; 26(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34361785

RESUMO

Even today, weeds continue to be a considerable problem for agriculture. The application of synthetic herbicides produces serious environmental consequences, and crops suffer loss of their activity due to the appearance of new resistant weed biotypes. Our aim is to develop new effective natural herbicides that improve the problem of resistance and do not harm the environment. This work is focused on a bioassay-guided isolation and the characterization of natural products present in Moquiniastrum pulchrum leaves with phytotoxic activity and its preliminary application in weeds. Moquiniastrum pulchrum was selected for two reasons: it is an abundant species in the Cerrado region (the second most important ecosystem in Brazil, after the Amazon)-the explanation behind its being a dominant species is a major focus of interest-and it has traditional employment in folk medicine. Six major compounds were isolated in this plant: one flavone and five diterpenes, two of which are described for the first time in the literature. Four of the six compounds exhibited phytotoxic activity in the bioassays performed. The results confirmed the phytotoxic potential of this plant, which had not been investigated until now.


Assuntos
Asteraceae/química , Agentes de Controle Biológico/toxicidade , Diterpenos/toxicidade , Flavonas/toxicidade , Herbicidas/toxicidade , Plantas Daninhas/efeitos dos fármacos , Controle de Plantas Daninhas/métodos , Bioensaio , Agentes de Controle Biológico/química , Agentes de Controle Biológico/isolamento & purificação , Produtos Agrícolas/crescimento & desenvolvimento , Diterpenos/química , Diterpenos/isolamento & purificação , Flavonas/química , Flavonas/isolamento & purificação , Herbicidas/química , Herbicidas/isolamento & purificação , Humanos , Estrutura Molecular , Extratos Vegetais/química , Folhas de Planta/química , Plantas Daninhas/crescimento & desenvolvimento
5.
Ecotoxicol Environ Saf ; 222: 112490, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34237638

RESUMO

As pesticides can be degraded to toxic metabolites in the soil, metabolite toxicity should be considered in human health risk assessments. In this study, a screening-level modeling framework was developed to manage pesticides in surface soil, which was discussed under discrete and continuous emission scenarios. In addition, we selected glyphosate and its major metabolite (aminomethylphosphonic acid or AMPA) as examples to conduct screening-level risk management at regional, national, and global scales. The results indicated that if soil AMPA were not considered, human health risks could be significantly underestimated because of the large half-life of AMPA in the soil. For example, the added concentration factors of AMPA were simulated as 0.19 and 6.72 considering all major elimination pathways and considering the degradation pathway alone, respectively, indicating that AMPA formation could lead to severe extra health burdens. Furthermore, the evaluation of current glyphosate soil standards suggested that toxic metabolites should be considered in the regulatory process; otherwise, many standards could theoretically trigger high levels of soil AMPA, which could result in serious human health damage. Our proposed screening-level model can help to improve risk assessment and regulatory management of pesticides in surface soils.


Assuntos
Herbicidas , Praguicidas , Poluentes do Solo , Monitoramento Ambiental , Herbicidas/análise , Herbicidas/toxicidade , Humanos , Organofosfonatos , Praguicidas/toxicidade , Medição de Risco , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
6.
Aquat Toxicol ; 237: 105909, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34273773

RESUMO

Aquatic herbicides are commonly used to control a wide variety of invasive and nuisance plants. One common active ingredient used in commercial herbicide formulations in Midwestern states is 2,4-dichlorophenoxyacetic acid (2,4-D). Due to the stability of 2,4-D in aquatic environments, many non-target aquatic species experience prolonged exposure throughout critical developmental life stages that can affect essential behaviors. However, the impacts of 2,4-D exposure on learning behaviors in juvenile fish are poorly understood. Therefore, we conducted a series of experiments using a maze environment to determine the effects of a commercial 2,4-D amine salt herbicide formulation (Weedestroy®AM40; WAM40; at 0.00, 0.50, 2.00, and 50.00 mg/L 2,4-D acid equivalent (a.e.)) exposure on juvenile yellow perch's ability to perform a feed associated learning behavior. We observed a significant decrease in the ability of yellow perch to correctly complete the feed associated learning behavior within 200 s when exposed to WAM40 at 2.00 and 50.00 mg/L 2,4-D as compared to controls (p = 0.0002; p < 0.0001, respectively) and within 600 s when exposed to WAM40 at 2.00 and 50.0 mg/L 2,4-D as compared to the controls (p = 0.0107 and p < 0.0001). These data suggest that exposure to 2,4-D in WAM40 can both increase the amount of time it takes for yellow perch to complete a feed associated learning behavior and/or obstruct the behavior altogether. Further experiments showed no significant decreases in locomotion (p > 0.05), hunger motivation (p > 0.05), and a visually guided startle response (p > 0.05), in all treatment groups tested as compared to controls. This suggests that 2,4-D in WAM40 does not inhibit feed associated learning behaviors via interaction with these mechanisms. Altogether, the results indicate that the use of 2,4-D herbicides for weed control in aquatic ecosystems could present risks to cognitive functions that control essential behaviors of yellow perch.


Assuntos
Herbicidas , Percas , Poluentes Químicos da Água , Ácido 2,4-Diclorofenoxiacético/toxicidade , Animais , Ecossistema , Herbicidas/análise , Herbicidas/toxicidade , Poluentes Químicos da Água/toxicidade
7.
J Agric Food Chem ; 69(30): 8366-8379, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34310139

RESUMO

Fenoxaprop-p-ethyl (FE), a type of acetyl-CoA carboxylase (ACCase) inhibitor, has been extensively applied to a variety of crop plants. It can cause damage to wheat (Triticum aestivum) even resulting in the death of the crop. On the prerequisite of not reducing herbicidal efficiency on target weed species, herbicide safeners selectively protect crops from herbicide injury. Based on fragment splicing, a series of novel substituted pyrazole derivatives was designed to ultimately address the phytotoxicity to wheat caused by FE. The title compounds were synthesized in a one-pot way and characterized via infrared spectroscopy, 1H nuclear magnetic resonance, 13C nuclear magnetic resonance, and high-resolution mass spectrometry. The bioactivity assay proved that the FE phytotoxicity to wheat could be reduced by most of the title compounds. The molecular docking model indicated that compound IV-21 prevented fenoxaprop acid (FA) from reaching or acting with ACCase. The absorption, distribution, metabolism, excretion, and toxicity predictions demonstrated that compound IV-21 exhibited superior pharmacokinetic properties to the commercialized safener mefenpyr-diethyl. The current work revealed that a series of newly substituted pyrazole derivatives presented strong herbicide safener activity in wheat. This may serve as a potential candidate structure to contribute to the further protection of wheat from herbicide injury.


Assuntos
Ésteres , Herbicidas , Herbicidas/toxicidade , Simulação de Acoplamento Molecular , Pirazóis/toxicidade , Recombinação Genética
8.
Environ Sci Technol ; 55(15): 10558-10568, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34286960

RESUMO

Misuse of agrochemicals has a long-lasting negative impact on aquatic systems. Mismanagement of herbicides in agri-food sectors is often linked to a simultaneous decline in the health of downstream waterways. However, monitoring the herbicide levels in these areas is a laborious task, and modern analytical approaches, such as solid-phase extraction-liquid chromatography-mass spectrometry (SPE-LC-MS) and enzyme-linked immunosorbent assay, are low-throughput and require significant sample preparation. We report here the use of microchip technology in combination with matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) for the assessment of the ecotoxicological effect of agrochemicals on aquatic species at the single-cell level. This approach quantifies the fluctuations in lipid content in sentinel organisms and targets the microalga, Chlamydomonas reinhardtii (C. reinhardtii), as the model system. Specifically, we investigated the cytotoxicity of three herbicides (atrazine, clomazone, and norflurazon) on C. reinhardtii by analyzing the lipid component variation upon assorted herbicide exposure. Lipidomic profiling reveals a significantly altered lipid content at >EC50 in atrazine-exposed cells. The response for norflurazon showed similar trends but diminished in magnitude, while the result for clomazone was near muted. At lower herbicide concentrations, digalactosyldiacylglycerols showed a rapid decrease in abundance, while several other lipids displayed a moderate increase. The microchip-based MALDI technique demonstrates the ability to achieve lipidomic profiling of aquatic species exposed to different stressors, proving effective for high-throughput screening and single-cell analysis in ecotoxicity studies.


Assuntos
Atrazina , Chlamydomonas reinhardtii , Herbicidas , Herbicidas/toxicidade , Lipidômica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
9.
BMC Genomics ; 22(1): 521, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34238252

RESUMO

BACKGROUND: Chinese sprangletop [Leptochloa chinensis (L.) Nees] is an annual malignant weed, which can often be found in paddy fields. Cyhalofop-butyl is a specialized herbicide which is utilized to control L. chinensis. However, in many areas, L. chinensis has become tolerant to this key herbicide due to its continuous long-term use. RESULTS: In this study, we utilized a tolerant (LC18002) and a sensitive (LC17041) L. chinensis populations previously identified in our laboratory, which were divided into four different groups. We then employed whole transcriptome analysis to identify candidate genes which may be involved in cyhalofop-butyl tolerance. This analysis resulted in the identification of six possible candidate genes, including three cytochrome P450 genes and three ATP-binding cassette transporter genes. We then carried out a phylogenetic analysis to identify homologs of the differentially expressed cytochrome P450 genes. This phylogenetic analysis indicated that all genes have close homologs in other species, some of which have been implicated in non-target site resistance (NTSR). CONCLUSIONS: This study is the first to use whole transcriptome analysis to identify herbicide non-target resistance genes in L. chinensis. The differentially expressed genes represent promising targets for better understanding herbicide tolerance in L. chinensis. The six genes belonging to classes already associated in herbicide tolerance may play important roles in the metabolic resistance of L. chinensis to cyhalofop-butyl, although the exact mechanisms require further study.


Assuntos
Acetil-CoA Carboxilase , Herbicidas , Acetil-CoA Carboxilase/genética , Butanos , China , Perfilação da Expressão Gênica , Resistência a Herbicidas/genética , Herbicidas/toxicidade , Nitrilas , Filogenia , Proteínas de Plantas/genética
10.
Pestic Biochem Physiol ; 177: 104897, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34301359

RESUMO

To seek novel and safe protoporphyrinogen oxidase (PPO, EC 1.3.3.4) inhibitors with excellent herbicidal activity. A series of novel phenoxypyridine derivatives containing natural product coumarins with allelopathy were designed and synthesized based on bioisosterism and active subunit combination in this research. Compounds W3.1 and W3.4, with the half-maximal inhibitory concentration (IC50) value of 0.02653 mg/L and 0.01937 mg/L, respectively, displayed excellent herbicidal activity in greenhouse. Their herbicidal activity was similar to commercial herbicide oxyfluorfen (IC50 = 0.04943 mg/L). The best field inhibitory effect of compounds W3.1 and W3.4 recorded was at doses of 450 g ai/ha and 300 g ai/ha, respectively. Compound W3.4 had the best herbicidal activity among all the target compounds in this paper. Molecular docking analysis revealed that compounds W3.1 and W3.4 could form a hydrogen bonds with the amino acid AGR-98 and a π-π superposition with the amino acid PHE-398, respectively, which was similar to the oxyfluorfen. The crop selectivity tests results indicated that maize, cotton and soybean showed high tolerance to compound W3.4. Compound W3.4 reduced the Ca and Cb contents of wheat and rice, but had less effect on maize, cotton and soybean. Selectivity of compound W3.4 in maize, cotton and soybean were appeared to be due to reduced absorption of the herbicide compared to wheat and rice. Compound W3.4 deserves further attention as a candidate structure for new herbicides.


Assuntos
Produtos Biológicos , Herbicidas , Alelopatia , Cumarínicos/farmacologia , Inibidores Enzimáticos/farmacologia , Herbicidas/toxicidade , Simulação de Acoplamento Molecular , Oxirredutases , Plantas Daninhas , Relação Estrutura-Atividade
11.
Molecules ; 26(12)2021 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-34199157

RESUMO

The influence of p-terphenyl polyketides 1-3 from Aspergillus candidus KMM 4676 and cerebroside flavuside B (4) from Penicillium islandicum (=Talaromyces islandicus) against the effect of neurotoxins, rotenone and paraquat, on Neuro-2a cell viability by MTT and LDH release assays and intracellular ROS level, as well as DPPH radical scavenging activity, was investigated. Pre-incubation with compounds significantly diminished the ROS level in rotenone- and paraquat-treated cells. It was shown that the investigated polyketides 1-3 significantly increased the viability of rotenone- and paraquat-treated cells in two of the used assays but they affected only the viability of paraquat-treated cells in the LDH release assay. Flavuside B statistically increased the viability of paraquat-treated cells in both MTT and LDH release assays, however, it increased the viability of rotenone-treated cells in the LDH release assay. Structure-activity relationships for p-terphenyl derivatives, as well as possible mechanisms of cytoprotective action of all studied compounds, were discussed.


Assuntos
Aspergillus/química , Citoproteção/efeitos dos fármacos , Glicoesfingolipídeos/farmacologia , Neuroblastoma/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Neurotoxinas/toxicidade , Policetídeos/farmacologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Herbicidas/toxicidade , Inseticidas/toxicidade , Camundongos , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Fármacos Neuroprotetores/química , Paraquat/toxicidade , Policetídeos/química , Espécies Reativas de Oxigênio , Rotenona/toxicidade
12.
J Hazard Mater ; 417: 125694, 2021 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-34229404

RESUMO

We evaluate the isolated and combined effects of glyphosate and its by-product aminomethylphosphonic acid (AMPA) and the potential of the aquatic macrophyte Salvinia molesta to remove these chemicals from contaminated water. Plants were exposed to environmentally relevant concentrations of glyphosate (0, 20, 40, 60, 80 and 100 µg l-1) or AMPA (0, 10, 20, 30, 40 and 50 µg l-1) for seven days. Then, based on the effective concentrations of glyphosate found to reduce photosynthetic rates by 10% (EC10) and 50% (EC50), the plants were exposed to combinations of 0, 16 and 63.5 µg glyphosate l-1 and 0, 5, 15, 25 µg AMPA l-1. The EC(10) and EC(50) were lower for AMPA (6.1 µg l-1 and 28.4 µg l-1 respectively) than for glyphosate (16 and 63.5 µg glyphosate l-1 respectively). When occurring together, the deleterious effects of those chemicals to plants increased. S. molesta plants removed up to 74.15% of glyphosate and 71.34% of AMPA from culture water. Due to its high removal efficiency, S. molesta can be used in phytoremediation programs. It will be important to evaluate the combined effects of glyphosate and AMPA in any toxicological studies of the herbicide.


Assuntos
Herbicidas , Água , Glicina/análogos & derivados , Glicina/toxicidade , Herbicidas/análise , Herbicidas/toxicidade , Organofosfonatos , Tetrazóis/toxicidade
13.
Environ Sci Process Impacts ; 23(7): 1018-1028, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34288996

RESUMO

Glyphosate degradation has been extensively examined; however, only a few detailed computational studies have been performed on the topic so far. There are substantial differences between the degradation products of glyphosate, as AMPA (aminomethylphosphonic acid) is toxic while sarcosine intermediate is non-toxic. These species can have different effects on the environment and, indirectly, on the human body. We performed calculations using density functional theory and post-Hartree-Fock correlated ab initio methods to find the possible mechanisms for the degradation process by small (hydroxyl, peroxyl, and superoxide) radicals. We found that direct sarcosine formation is strongly dependent on the concentration of the radical species. AMPA and glycine were mostly formed as aldehyde derivatives, while in addition to the former, glyoxylate and bicarbonate are formed alternatively. A significant pH effect was also found for the competitive reactions determined by the calculated rate constants of the elementary steps. Overall barriers showed similarities by DFT but ab initio methods could separate them.


Assuntos
Herbicidas , Glicina/análogos & derivados , Glicina/toxicidade , Herbicidas/toxicidade , Humanos , Radical Hidroxila , Organofosfonatos
14.
Environ Pollut ; 287: 117635, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34182386

RESUMO

The presence of atrazine, a triazine herbicide, and its residues in agriculture soil poses a serious threat to human health and environment through accumulation in edible plant parts. Hence, the present study focused on atrazine induced stress amelioration of Andrographis paniculata, an important medicinal plant, by a plant growth promoting and atrazine degrading endophytic bacterium CIMAP-A7 inoculation. Atrazine has a non-significant effect at a lower dose while at a higher dose (lower: 25 and higher: 50 mg kg-1) 22 and 36% decrease in secondary metabolite content and plant dry weight of A. paniculata was recorded, respectively. Endophyte CIMAP-A7 inoculation significantly reduced atrazine soil content, by 78 and 51% at lower and a higher doses respectively, than their respective control treatments. Inoculation of CIMAP-A7 exhibited better plant growth in terms of increased total chlorophyll, carotenoid, protein, and metabolite content with reduced atrazine content under both atrazine contaminated and un-contaminated treatments. Atrazine induced oxidative stress in A. paniculata was also ameliorated by CIMAP-A7 by reducing stress enzymes, proline, and malondialdehyde accumulation under contaminated soil conditions than un-inoculated treatments. Furthermore, the presence of atrazine metabolites deisopropylatrazine (DIA) and desethylatrazine (DEA) strongly suggests a role of CIMAP-A7 in mineralization however, the absence of these metabolites in uninoculated soil and all plant samples were recorded. These findings advocate that the amelioration of atrazine induced stress with no/least pesticide content in plant tissues by plant-endophyte co-interactions would be efficient in the remediation of atrazine contaminated soils and ensure safe crop produce.


Assuntos
Andrographis , Atrazina , Herbicidas , Poluentes do Solo , Atrazina/análise , Atrazina/toxicidade , Biodegradação Ambiental , Herbicidas/toxicidade , Humanos , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
15.
Chemosphere ; 283: 131226, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34146870

RESUMO

Butachlor is a systemic herbicide widely applied on wheat, rice, beans, and different other crops, and is frequently detected in groundwater, surface water, and soil. Therefore, it is necessary to investigate the potential adverse health risks and the underlying mechanisms of hepatotoxicity caused by exposure to butachlor in invertebrates, other nontarget animals, and public health. For this reason, a total of 20 mice were obtained and randomly divided into two groups. The experimental mice in one group were exposed to butachlor (8 mg/kg) and the mice in control group received normal saline. The liver tissues were obtained from each mice at day 21 of the trial. Results indicated that exposure to butachlor induced hepatotoxicity in terms of swelling of hepatocyte, disorders in the arrangement of hepatic cells, increased concentrations of different serum enzymes such as alkaline phosphate (ALP) and aspartate aminotransferase (AST). The results on the mechanisms of liver toxicity indicated that butachlor induced overexpression of Apaf-1, Bax, Caspase-3, Caspase-9, Cyt-c, p53, Beclin-1, ATG-5, and LC3, whereas decreases the expression of Bcl-2 and p62 suggesting abnormal processes of apoptosis and autophagy. Results on different metabolites (61 differential metabolites) revealed upregulation of PE and LysoPC, whereas downregulation of SM caused by butachlor exposure in mice led to the disruption of glycerophospholipids and lipid metabolism in the liver. The results of our experimental research indicated that butachlor induces hepatotoxic effects through disruption of lipid metabolism, abnormal mechanisms of autophagy, and apoptosis that provides new insights into the elucidation of the mechanisms of hepatotoxicity in mice induced by butachlor.


Assuntos
Herbicidas , Acetanilidas/toxicidade , Animais , Herbicidas/toxicidade , Metabolismo dos Lipídeos , Fígado , Camundongos
16.
Chemosphere ; 283: 131227, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34147975

RESUMO

Atrazine is considered as a potential environmental endocrine disruptors and exhibits various toxic effects on animals. It has a great impact in the aquatic ecosystems, but there are few studies on its immunotoxicity in crustaceans. In the present study, the Procambarus clarkii were utilized to assess the immune toxicity after 0.5 mg/L and 5 mg/L atrazine exposure. A significant decrease in total hemocytes count (THC) was observed at 5 mg/L atrazine exposure throughout the experiment. The activities of antioxidant enzymes including superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) were significantly inhibited, but the content of reactive oxygen species (ROS) and malondialdehyde (MDA) were up-regulated, indicating the potential oxidative stress. The analysis of the integrated biomarker response (IBR) showed the induction of oxidative stress biomarkers and the inhibition of antioxidants. After 5 mg/L atrazine exposure for 144 h, the integrity of crayfish hepatopancreas was destroyed with disappeared connections between tubules and increased liver tubules vacuoles. The relative expression levels of different immune genes in hepatopancreas after atrazine exposure were measured. Most of these genes were suppressed and exhibited a certain dose-dependent effect. The results of crayfish white spot syndrome virus (WSSV) replication shown the amount of virus in muscle was significantly higher and exhibited a higher mortality rate at 5 mg/L group than other groups. The present study determined the impact of atrazine exposure on WSSV outbreaks, and also provide an important basis for further assessing the occurrence of pesticides on diseases of P. clarkii.


Assuntos
Atrazina , Herbicidas , Vírus da Síndrome da Mancha Branca 1 , Animais , Astacoidea , Atrazina/toxicidade , Proliferação de Células , Ecossistema , Herbicidas/toxicidade , Estresse Oxidativo
17.
Aquat Toxicol ; 237: 105894, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34186419

RESUMO

The environmental safety profile of glyphosate, the most commonly used herbicide worldwide, is still a subject of debate and little is known about the generational toxicity of this active substance (AS) and the associated commercial formulations called "glyphosate-based herbicides" (GBHs). This study investigated the impact of parental and direct exposure to 1µgL-1 of glyphosate using the AS alone or one of two GBH formulations (i.e. Roundup Innovert® and Viaglif Jardin®) in the early developmental stages of rainbow trout. Three different modes of exposure on the F1 generation were studied: (1) intergenerational (i.e. fish only exposed through their parents); (2) direct (i.e. fish exposed only directly) and (3) multigenerational (i.e. fish both exposed intergenerationally and directly). The impact of chemical treatments on embryo-larval development (survival, biometry and malformations), swimming behaviour, biochemical markers of oxidative stress equilibrium (TBARS and catalase), acetylcholine esterase (AChE) and energy metabolism (citrate synthase, CS; cytochrome-c oxidase, CCO; lactate dehydrogenase, LDH; glucose-6-phosphate dehydrogenase, G6PDH) was explored. Chemical exposure did not affect the survival of F1 embryos or malformation rates. Direct exposure to the AS induced some biometric changes, such as reduction in head size (with a 10% decrease in head length), independently of co-formulants. Intergenerational exposure to the AS or the Roundup GBH increased swimming activity of the larvae, with increase of between 78 and 102% in travel speeds. Viaglif co-formulants appear to have counteracted this behavioural change. The minor changes detected in the assayed biochemical markers suggested that observed effects were not due to oxidative damage, AChE inhibition or alterations to energy metabolism. Nonetheless, multi- and intergenerational exposure to Roundup increased CS:CCO and LDH:CS ratios by 46% and 9%, respectively, with a potential modification of the aerobic-to-anaerobic energy production balance. These biochemical effects were not correlated with those observed on individual level of biological organization. Therefore, further studies on generational toxicity of glyphosate and its co-formulants are needed to identify the other mechanisms of glyphosate toxicity at the cellular level.


Assuntos
Herbicidas , Oncorhynchus mykiss , Poluentes Químicos da Água , Animais , Glicina/análogos & derivados , Glicina/toxicidade , Herbicidas/toxicidade , Larva , Poluentes Químicos da Água/toxicidade
18.
Theriogenology ; 172: 55-66, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34102463

RESUMO

The use of worldwide glyphosate-based herbicide Roundup® is growing and to date its effects on mammalian spermatozoa are controversial. This study aims to investigate the functional impact of in vitro exposure of pig spermatozoa to low concentrations of Roundup® Ultra Plus (RUP), similar to those present as environment contaminants, to its active ingredient glyphosate, and to the non-active component, surfactant polyoxyethyleneamine (POEA). Pig spermatozoa were incubated in Tyrode's basal medium (TBM) or Tyrode's complete medium (TCM) (1 h at 38.5 °C) with several RUP dilutions or equivalent concentrations of glyphosate or POEA. RUP treatment causes a significant dilution-dependent decrease in sperm motility, a significant increase in plasma membrane disorganization and reduction in GSK3ß phosphorylation (TBM) and in two PKA substrates (TBM and TCM), whereas does not affect sperm viability or mitochondrial membrane potential (MMP). Equivalent glyphosate concentrations do not affect any functional sperm parameters. However, POEA concentrations equivalent to RUP dilutions mimic all RUP sperm effects: decrease sperm motility in a concentration-dependent manner, increase sperm plasma membrane lipid disorder and significantly inhibit GSK3ß phosphorylation (TBM) and two PKA substrates without affecting sperm viability or MMP. In summary, low concentrations RUP herbicide cause sperm motility impairment without affecting sperm viability. This adverse effect could be likely due to a detrimental effect in the plasma membrane lipid organization and to inhibition of phosphorylation of both, GSK3ß and specific PKA substrates. Importantly, our results indicate that negative effects of low RUP concentrations in pig spermatozoa function are likely caused by the surfactant included in its formulation and no by its active ingredient glyphosate.


Assuntos
Herbicidas , Animais , Herbicidas/toxicidade , Masculino , Fosforilação , Motilidade Espermática , Espermatozoides , Tensoativos , Suínos
19.
Chemosphere ; 282: 130976, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34089999

RESUMO

Atrazine is one of the most widely used herbicides, however it and its metabolites cause widespread contamination in soil and ground water. Bioaugmentation is an effective method for remediation of environmental organic pollutants. High-throughput sequencing provides an important tool for understanding the changes of microbial community and function in response to pollutants degradation based on bioaugmentation. In this study, the effect of biodegradation with Paenarthrobacter sp. W11 and the change of microbial community during atrazine degradation were investigated. The results showed that bioaugmentation significantly accelerated the degradation rate of atrazine in soil and reduced the toxic effect of atrazine residues on wheat growth. The extra available NH4+ through atrazine mineralization could serve as a nitrogen source to increase microbial numbers. High-throughput sequencing further revealed that the microbial community restored a new balance. The function of microbial community predicted by PICRUSt2 suggested that the biodegradation process of atrazine affected not only the atrazine degradation pathway, but also the nitrogen metabolism pathway. Methylobacillus and Pseudomonas were considered as the most important indigenous atrazine-degrading microorganisms, because their relative abundances were positively correlated with the relative abundance of Paenarthrobacter and atrazine degradation pathway. This study provides insight into the cooperation between indigenous microorganisms and external inoculums on atrazine degradation process.


Assuntos
Atrazina , Herbicidas , Poluentes do Solo , Atrazina/análise , Atrazina/toxicidade , Biodegradação Ambiental , Herbicidas/análise , Herbicidas/toxicidade , Solo , Microbiologia do Solo , Poluentes do Solo/análise
20.
Chemosphere ; 282: 131104, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34118626

RESUMO

River biofilm communities are the first ones to be exposed to all toxic discharges received via run off from agricultural fields. Hence, changes in river biofilm community structure and growth pattern are considered as indicator of overall health of lotic ecosystem. Toxicants have effect on biofilm biomass, photosynthetic efficiency and chlorophyll a concentrations. Mathematical models may be applied to estimate the overall vigor of riverine ecosystems considering biofilms as indicators. Herein, previous empirical data of Ricart et al. (2009) on long term effects of environmentally relevant concentrations of diuron on biofilm communities of the River Llobregat, Spain was considered as our model inputs. Our objective is to understand the influence of diuron, chlorophyll a concentrations and photosynthetic efficiency on biovolume using a statistical model. The non-linear relationships between biovolume (dependent variable) and diuron, chlorophyll a concentrations and photosynthetic efficiency (independent variables) were represented by constructing three separate basis functions based on day 8 empirical data. Biovolume, due to nonlinear influence as yielded by the basis functions were used in a multiple linear regression model to estimate the net biovolume. Model validation was done based on day 29 empirical data. The experimentally determined biovolume and our model estimated biovolume showed similar trends. Also, diuron and photosynthetic efficiency had significant (p < 0.05) influence on biovolume. Since, the predominance of diatoms as biofilms within periphytic layers is very common in lotic systems, estimation of changes in diatom biovolume will be significant to assess the effect of herbicides. Diatom biovolume of any day (for example day 22) mentioned in the experimental study may be determined by this model, without the requirement of tedious manual biovolume calculation. Our model will be useful in numerous other studies undertaken on the toxic effect of pollutants on biofilms to quickly and accurately estimate the biofilm biovolume.


Assuntos
Diatomáceas , Herbicidas , Poluentes Químicos da Água , Biofilmes , Clorofila A , Diurona/toxicidade , Ecossistema , Herbicidas/toxicidade , Modelos Estatísticos , Rios , Poluentes Químicos da Água/toxicidade
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