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1.
Chemosphere ; 244: 125543, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32050340

RESUMO

Environmentally friendly and cost-effective techniques are required to reclaim land degraded during mining activities. Bioaccumulation of heavy metals (HMs) in vegetables grown on contaminated soils can increase human health risks. The potential effects of hardwood biochar (HWB) was assessed for chromium (Cr), zinc (Zn), copper (Cu), manganese (Mn) and lead (Pb) bioavailability in mine-contaminated soils and their subsequently bioaccumulation in crops and associated health risk. HWB was applied to chromium-manganese mine contaminated soils at the rate of 3% to investigate the efficiency of HWB for the second crop in crop rotation technique. Cilantro (Coriandrum sativum) and spinach (Spinaccia oleracea) were grown as second crop in the same pots which were already used for rice cultivation as first crop (without adding further amendments). Application of HWB decreased the concentrations of Cr, Zn, Cu, Mn, and Pb in cilantro by 25.5%, 37.1%, 42.5%, 34.3%, and 36.2%, respectively as compared to control. In spinach, the reduction in concentrations of Cr was 75.0%, Zn 24.1%, Cu 70.1%, Mn 78.0%, and Pb 50.5% as compared to control. HWB significantly (P < 0.01) reduced the HMs uptake in spinach cultivated in the amended soils as compared to the spinach in control. Bioaccumulation factor results also indicate that HWB decreased the bioaccumulation of selected HMs in cilantro and spinach, thus reducing health risks. Results of the study clearly demonstrate that the use of HWB can significantly reduce HMs in vegetables, associated health risk and improve food quality, therefore can be used as soil amendment for reclamation of mine-degraded soils.


Assuntos
Carvão Vegetal , Coriandrum/metabolismo , Metais Pesados/metabolismo , Poluentes do Solo/metabolismo , Spinacia oleracea/metabolismo , Agricultura/estatística & dados numéricos , Disponibilidade Biológica , Cobre/metabolismo , Produtos Agrícolas/metabolismo , Exposição Dietética/estatística & dados numéricos , Humanos , Manganês/metabolismo , Metais Pesados/análise , Mineração , Oryza/metabolismo , Solo , Poluentes do Solo/análise , Verduras/metabolismo , Zinco/análise
2.
Ecotoxicol Environ Saf ; 191: 110177, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31958627

RESUMO

Advances in large hydroponic production of leafy greens, easy adoption in urban agriculture, and large leaf surface area of many leafy greens, greatly increase their exposure to heavy metals and nanoparticles. Cadmium (Cd) and lead (Pb) are two highly toxic heavy metals, which threaten the health of humans and livestock even at trace levels. These heavy metals may be taken up by plant roots through the protein transporters used for essential minerals such as iron (Fe2+) and copper (Cu2+). Previous studies have shown that some metallic nanoparticles affect the performance of protein transporters and modify the plant uptake of co-existing heavy metal ions. This study aims to understand the role of zinc oxide nanoparticles (ZnONPs) in the uptake pattern of Cd and Pb and two key micronutrients of iron and copper in edible tissues of three leafy green species including spinach (Spinaciae oleracea), parsley (Petroselinum sativum) and cilantro (Coriandrum sativum). Pre-grown plant seedlings in soil (containing Cu and Fe) were transplanted to a hydroponic system (1/4th Hoagland solution) for 7 days as a transition, and then were exposed to four treatments in deionized water (1.0 mg L-1 Cd2++100.0 mg L-1 Pb2+, 1.0 mg L-1 Cd2++100.0 mg L-1 Pb2+ + 100 mg L-1 ZnONPs, 100 mg L-1 ZnO-ENPs and a control with no chemical exposure) for additional two weeks. At termination, shoots were gently separated from the roots, and the concentrations of Pb, Cd, Fe, Zn, and Cu in all plant tissues were quantified by inductively coupled plasma-mass spectrometry (ICP-MS). The results revealed that ZnONPs mitigated the uptake of both heavy metals in roots. The translocation of heavy metals was similar in the edible tissues of three species. The response of three leafy greens to the co-exposure of heavy metals and ZnONPs was different in Cu and Fe accumulation in edible tissues. Fe concentration in edible tissues in the co-exposed plants was increased in spinach (+10%) and cilantro (+9%) but decreased in parsley (-8%) compared to controls, while the Cu level in edible tissues increased in all three species following the order of cilantro (+8%)> spinach (+4%)> parsley (+1.5%).


Assuntos
Produtos Agrícolas/metabolismo , Metais Pesados/metabolismo , Nutrientes/metabolismo , Poluentes Químicos da Água/metabolismo , Óxido de Zinco/metabolismo , Disponibilidade Biológica , Cádmio/metabolismo , Cobre/metabolismo , Produtos Agrícolas/classificação , Produtos Agrícolas/crescimento & desenvolvimento , Hidroponia , Ferro/metabolismo , Chumbo/metabolismo , Nanopartículas/química , Nanopartículas/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Especificidade da Espécie , Óxido de Zinco/química
3.
Nat Commun ; 11(1): 557, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992699

RESUMO

Hydrogen sulfide (H2S) is involved in numerous pathophysiological processes and shares overlapping functions with CO and •NO. However, the importance of host-derived H2S in microbial pathogenesis is unknown. Here we show that Mtb-infected mice deficient in the H2S-producing enzyme cystathionine ß-synthase (CBS) survive longer with reduced organ burden, and that pharmacological inhibition of CBS reduces Mtb bacillary load in mice. High-resolution respirometry, transcriptomics and mass spectrometry establish that H2S stimulates Mtb respiration and bioenergetics predominantly via cytochrome bd oxidase, and that H2S reverses •NO-mediated inhibition of Mtb respiration. Further, exposure of Mtb to H2S regulates genes involved in sulfur and copper metabolism and the Dos regulon. Our results indicate that Mtb exploits host-derived H2S to promote growth and disease, and suggest that host-directed therapies targeting H2S production may be potentially useful for the management of tuberculosis and other microbial infections.


Assuntos
Sulfeto de Hidrogênio/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/metabolismo , Mycobacterium tuberculosis/patogenicidade , Animais , Cobre/metabolismo , Cistationina beta-Sintase/genética , Cistationina beta-Sintase/metabolismo , Citocinas/sangue , Modelos Animais de Doenças , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Metabolismo Energético , Feminino , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Homeostase , Pulmão/patologia , Macrófagos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mycobacterium tuberculosis/genética , Células RAW 264.7 , Regulon , Enxofre/metabolismo , Transcriptoma , Tuberculose
4.
Chemosphere ; 243: 125399, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31995869

RESUMO

Nutrient removal efficiency in green sorption media such as biosorption activated media (BAM) for treating stormwater runoff can be heavily influenced either on a short- or long-term basis by varying field conditions of linear ditches due to the presence of copper in stormwater runoff. It is also noticeable that the linear ditch undergoes physical or mechanical impacts from the traffic compaction, chemical impact of carbon sources from the nearby farmland, and biological impact from potential animal activities (such as gopher tortoises, moles, and ants). In the nitrogen cycle, two denitrification pathways, the dissimilatory nitrate reduction to ammonia and common denitrification, are deemed critical for such assessment. A fixed-bed column study was set up to mimic different linear ditch field conditions for BAM applications and measure the effect of short-and long-term copper addition on microbial dynamics given the varying decomposition of dissolved organic nitrogen (DON). The findings confirm that, as the denitrifiers (in the second pathway) were the dominant species, their population continued to grow and maintain small-sized cells for extracellular sequestration under long-term copper impact. Furthermore, the study indicated that the ammonia oxidizer comammox was found in higher quantities than ammonia oxidizing bacteria or archaea. An enormous amount of DON was released during this process to bind the copper ion and reduce its toxicity as the enzymatic cascade effect appeared. In addition, the long-term copper exposure posed salient inhibitory effects on the microbial community regardless of varying field conditions in BAM. Short-term copper toxicity exerted an important but varying role in the enzymatic cascade effect over different linear ditch field conditions in BAM.


Assuntos
Cobre/química , Enzimas/metabolismo , Nitrogênio/isolamento & purificação , Purificação da Água/métodos , Amônia/metabolismo , Carbono , Cobre/metabolismo , Desnitrificação , Enzimas/química , Consórcios Microbianos/efeitos dos fármacos , Nitratos/metabolismo
5.
Environ Sci Pollut Res Int ; 27(8): 8662-8672, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31907812

RESUMO

Over the past decades, the important topic of environmental sustainability, impact, and security of the fossil fuel supply has stimulated interest in using lignocellulosic feedstocks as biofuel to partially cover energy demands. Among energy no-food crops, giant reed (Arundo donax, L.), a perennial rhizomatous grass has been identified as a leading candidate crop for lignocellulosic feedstock, due to its positive energy balance, and low ecological/agro-management demands. The aim of the present study was to characterize the physiological response of Arundo donax (L.) to artificial soil contamination with three different Cu levels (200, 400, and 800 ppm), and to assess the relationship between plant Cu tolerance and S assimilation rate. The present study not only confirms the ability of Arundo donax L. to cope with Cu stress and therefore to grow in marginal, degraded lands abandoned by mainstream agricultural, but also shows that plant performance might be likely ascribed to a modulation of sulfate metabolism resulting in increased thiols content.


Assuntos
Biodegradação Ambiental , Cobre/análise , Poaceae/fisiologia , Poluentes do Solo/análise , Solo , Adaptação Fisiológica , Biocombustíveis , Biomassa , Cobre/metabolismo , Cobre/toxicidade , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade
6.
Chemistry ; 26(1): 249-258, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31710732

RESUMO

Superoxide dismutases (SODs) are highly efficient enzymes for superoxide dismutation and the first line of defense against oxidative stress. These metalloproteins contain a redox-active metal ion in their active site (Mn, Cu, Fe, Ni) with a tightly controlled reduction potential found in a close range around the optimal value of 0.36 V versus the normal hydrogen electrode (NHE). Rationally designed proteins with well-defined three-dimensional structures offer new opportunities for obtaining functional SOD mimics. Here, we explore four different copper-binding scaffolds: H3 (His3 ), H4 (His4 ), H2 DH (His3 Asp with two His and one Asp in the same plane) and H3 D (His3 Asp with three His in the same plane) by using the scaffold of the de novo protein GRα3 D. EPR and XAS analysis of the resulting copper complexes demonstrates that they are good CuII -bound structural mimics of Cu-only SODs. Furthermore, all the complexes exhibit SOD activity, though three orders of magnitude slower than the native enzyme, making them the first de novo copper SOD mimics.


Assuntos
Cobre/química , Metaloproteínas/química , Peptídeos/química , Sequência de Aminoácidos , Cobre/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Ensaios Enzimáticos , Metaloproteínas/metabolismo , Peptídeos/metabolismo , Estabilidade Proteica , Superóxido Dismutase/química , Superóxido Dismutase/metabolismo , Temperatura Ambiente , Termodinâmica
7.
Environ Pollut ; 256: 113397, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31662248

RESUMO

Mosses are frequently used to monitor atmospheric metal contamination but few studies on metal adsorption under controlled conditions are available. Here, the accumulation of the heavy metals copper and zinc was studied in the acrocarp moss Atrichum undulatum. An in vitro culture of A. undulatum was established and the same line, size and equally old remets were exposed to six different treatments representing various metal exposure times and washing scenarios as rain simulation. The metal treatments were done in copper and zinc salts (Cu-acetate, CuSO4, ZnSO4 and ZnCl2, respectively). Energy-Dispersive X-ray microanalysis (EDX) was employed to detect bound heavy metals on the moss plantlets. Element distribution in stems and leaves was measured separately. The aqueous solution of metal salts facilitated an adsorption of both elements in the moss tissue as compared to solid medium. Furthermore, A. undulatum can tolerate pollution of zinc and copper in a distinctive extent; our data point towards a higher zinc tolerance whereas copper is rather harmful. However, semi-quantitatively, less zinc was detected within the moss tissue compared to copper. Interestingly, a strong positive correlation between the accumulation of copper/zinc and iron, and a strong negative correlation between copper/zinc and magnesium, respectively, was documented.


Assuntos
Briófitas/química , Monitoramento Ambiental , Poluentes Ambientais/análise , Metais Pesados/análise , Adsorção , Briófitas/metabolismo , Cobre/metabolismo , Poluição Ambiental , Folhas de Planta/química , Zinco/metabolismo
8.
Chemosphere ; 242: 125141, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31677505

RESUMO

Diclofenac (DCF), a non-steroidal anti-inflammatory drug, is widespread in aquatic environments and coexists with heavy metals to form combined pollution. However, the interactive effects of DCF and heavy metals on aquatic organisms remain unknown. This study aimed to investigate the interactive effects of DCF and copper (Cu) on the bioconcentration, oxidative stress status and detoxification-related gene expression in crucian carp (Carassius auratus). Fish were exposed to Cu (100 µg L-1) and DCF (1, 10, 100 and 1000 µg L-1) alone or in combination for 7 days. Results obtained showed that the treatment of Cu combined with high levels of DCF (100 and 1000 µg L-1) significantly decreased tissue concentrations of DCF and Cu compared to the correspondingly individual exposure. Concerning oxidative stress status, as reflected by the activities of antioxidant enzymes and malondialdehyde content, low exposure concentrations of DCF (1 and 10 µg L-1) seemed to mitigate the oxidative stress induced by Cu, whereas the co-exposure of Cu with the highest level of DCF (1000 µg L-1) led to stronger oxidative damage in fish liver than Cu exposure alone. With regarding to detoxification-related genes, in most cases, the expressions of cyp 1a, cyp 3a, gstα, gstπ, pxr and P-gp in crucian carp were significantly altered upon exposure to the compounds in combination compared to exposure to the compounds individually. Collectively, these findings indicate the capacity of each of these pollutants to alter bioconcentration potential, pro-oxidative effects and detoxification-related gene responses of the other when both co-occur at specific concentrations.


Assuntos
Anti-Inflamatórios não Esteroides/toxicidade , Carpas/fisiologia , Cobre/toxicidade , Diclofenaco/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Anti-Inflamatórios não Esteroides/metabolismo , Bioacumulação , Biomarcadores/metabolismo , Carpas/metabolismo , Cobre/metabolismo , Diclofenaco/metabolismo , Carpa Dourada/metabolismo , Inativação Metabólica/efeitos dos fármacos , Fígado/metabolismo , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/metabolismo
9.
Bull Environ Contam Toxicol ; 104(1): 78-83, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31796979

RESUMO

This research was to evaluate the load and mobility of Cu in juvenile Litopenaeus vannamei after exposure (48 h) to sublethal concentration of nitrite (5.3 mg/L NO2--N) at a salinity of 3.0 g/L. The hypothesis is that such exposure causes a Cu mobility in the tissues of shrimp. The Cu concentration in exoskeleton, hepatopancreas, muscle and hemolymph in the control group were 38.9 ± 3.0, 2478 ± 256, 11.9 ± 0.2 µg/g (dw) and 95.4 ± 19.1 µg/mL, while in the nitrite exposure, were 46.0 ± 0.1, 1546 ± 173, 11.3 ± 0.3 µg/g (dw) and 118.2 ± 10.5 µg/mL, respectively. Only hepatopancreas exhibited a significant (p < 0.05) reduction (37.6%) between the control and the nitrite exposure. This is evidence that nitrite has a significant effect on Cu accumulation in hepatopancreas when shrimp are exposed to sublethal levels in a salinity of 3 g/L. Results confirm the hypothesis that Cu mobility was only significant in hepatopancreas.


Assuntos
Cobre/toxicidade , Hepatopâncreas/metabolismo , Nitritos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Cobre/metabolismo , Hemolinfa , Hepatopâncreas/efeitos dos fármacos , Nitritos/metabolismo , Penaeidae , Salinidade , Alimentos Marinhos , Poluentes Químicos da Água/metabolismo
10.
Aquat Toxicol ; 218: 105363, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31783302

RESUMO

The aquatic environment is continuously under threat because it is the final receptor and sink of waste streams. The development of industry, mining activities and agriculture gave rise to an increase in metal pollution in the aquatic system. Thus a wide occurrence of metal mixtures exists in the aquatic environment. The assessment of mixture stress remains a challenge considering that we can not predict the toxicity of a mixture on the basis of single compounds. Therefore the analysis of the effects of environmentally relevant waterborne mixtures is needed to improve our understanding of the impact of metal pollution in aquatic ecosystems. Our aim was to assess whether 10 % of the concentration of the 96 h LC50 (the concentration that is lethal to 50 % of the population in 96 h) of individual metal exposures can be considered as a "safe" concentration when applied in a trinomial mixture. Therefore, common carp were exposed to a sublethal mixture of Cu 0.07 ±â€¯0.001 µM (4.3 ±â€¯0.6 µg/L), Zn 2.71 ±â€¯0.81 µM (176.9 ±â€¯52.8 µg/L) and Cd 0.03 ±â€¯0.0004 µM (3.0 ±â€¯0.4 µg/L) at 20 °C for a period of one week. Parameters assessed included survival rate, bioaccumulation and physiological biomarkers related to ionoregulation and defensive mechanisms such as MT induction. Our results showed a sharp increase in Cu and Cd concentration in gills within the first day of exposure while Zn levels remained stable. The accumulation of these metals led to a Na drop in gills, liver and muscle as well as a decreased K content in the liver. Biomarkers related to Na uptake were also affected: on the first day gene expression for H+-ATPase was transiently increased while a concomitant decreased gene expression of the Na+/H+ exchanger occurred. A fivefold induction of metallothionein gene expression was reported during the entire duration of the experiment. Despite the adverse effects on ionoregulation all fish survived, indicating that common carp are able to cope with these low metal concentrations, at least during a one week exposure.


Assuntos
Bioacumulação , Cádmio/toxicidade , Carpas/metabolismo , Cobre/toxicidade , Poluentes Químicos da Água/toxicidade , Zinco/toxicidade , Animais , Bioacumulação/genética , Biomarcadores/metabolismo , Cádmio/metabolismo , Carpas/genética , Cobre/metabolismo , Ecossistema , Eletrólitos/metabolismo , Expressão Gênica/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Dose Letal Mediana , Metalotioneína/genética , ATPases Translocadoras de Prótons/genética , Poluentes Químicos da Água/metabolismo , Zinco/metabolismo
11.
Chem Commun (Camb) ; 56(3): 399-402, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31820751

RESUMO

A combinatorial approach using a one-bead-one-compound method and a screening based on a SOD-activity assay was set up for the discovery of an efficient peptidyl copper complex. The complex exhibited good stability constants, suitable redox potentials and excellent intrinsic activity. This complex was further assayed in cells for its antioxidant properties and showed beneficial effects when cells were subjected to oxidative stress.


Assuntos
Materiais Biocompatíveis/metabolismo , Cobre/química , Peptídeos/química , Sequência de Aminoácidos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Colo/citologia , Colo/efeitos dos fármacos , Colo/metabolismo , Cobre/metabolismo , Células HT29 , Humanos , Interleucina-8/metabolismo , Lipopolissacarídeos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Peptídeos/metabolismo , Superóxido Dismutase/metabolismo
12.
Environ Pollut ; 258: 113544, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31859126

RESUMO

Gradual contamination of agricultural land with copper (Cu), due to the indiscriminate uses of fungicides and pesticides, and the discharge of industrial waste to the environment, poses a high threat for soil degradation and consequently food crop production. In this study, we combined morphological, physiological and biochemical assays to investigate the mechanisms underlying acetate-mediated Cu toxicity tolerance in lentil. Results demonstrated that high dose of Cu (3.0 mM CuSO4. 5H2O) reduced seedling growth and chlorophyll content, while augmenting Cu contents in both roots and shoots, and increasing oxidative damage in lentil plants through disruption of the antioxidant defense. Principle component analysis clearly indicated that Cu accumulation and increased oxidative damage were the key factors for Cu toxicity in lentil seedlings. However, acetate pretreatment reduced Cu accumulation in roots and shoots, increased proline content and improved the responses of antioxidant defense (e.g. increased catalase and glutathione-S-transferase activities, and improved action of glutathione-ascorbate metabolic pathway). As a result, excess Cu-induced oxidative damage was reduced, and seedling growth was improved under Cu stress conditions, indicating the role of acetate in alleviating Cu toxicity in lentil seedlings. Taken together, exogenous acetate application reduced Cu accumulation in lentil roots and shoots and mitigated oxidative damage by activating the antioxidant defense, which were the major determinants for alleviating Cu toxicity in lentil seedlings. Our findings provide mechanistic insights into the protective roles of acetate in mitigating Cu toxicity in lentil, and suggest that application of acetate could be a novel and economical strategy for the management of heavy metal toxicity and accumulation in crops.


Assuntos
Antioxidantes , Cobre/metabolismo , Cobre/farmacologia , Homeostase/fisiologia , Lens (Planta)/metabolismo , Raízes de Plantas/metabolismo , Plântula/efeitos dos fármacos , Acetatos , Clorofila/metabolismo , Peróxido de Hidrogênio , Lens (Planta)/efeitos dos fármacos , Lens (Planta)/crescimento & desenvolvimento , Estresse Oxidativo , Folhas de Planta/metabolismo , Análise de Componente Principal
13.
Ecotoxicol Environ Saf ; 188: 109900, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31710868

RESUMO

Copper is an essential element in many biological processes, but may exert toxic effects at levels surplus to metabolic requirements. Herein we assess the effect of copper on zebrafish behaviour using two assays, namely the novel tank diving test and a T-maze test with food reward. Novel tank diving tests were conducted on days 0, 4, and 10 of a 10 day Cu exposure (at concentrations of 0.77 µM (25% of the 240 h LC50) and 1.52 µM (50% of the 240 h LC50) to assess the alterations of behavioural responses in repeating novel tank diving assays and the effect of Cu on these patterns. Results demonstrate habituation to novelty, which is an indicator of spatial memory. Copper exposure had no effect on the latency of entry into the upper zones of the tank, nor on the total time spent therein, but did cause a greater number of freezing bouts in comparison to the control group. Additionally, Cu exposure had no effect on the habituation responses of zebrafish. Using the T-maze assay, we tested the effect of prior exposure to Cu for 10 days on subsequent behavioural trainings. The T-maze protocol was based on associative learning, where a visual stimulus (colour) was linked with a natural stimulus (food). Results of the control group showed that zebrafish are able to perform associative learning tasks. Moreover, Cu was found to negatively affect the associative learning capabilities. Specifically, while zebrafish in the control group achieved a significant number of correct choices (leading to food reward) throughout the T-maze training, such a trend was not observed for Cu exposed fish. Thus at the exposure concentrations and exposure times considered herein, Cu has no determinative impact on instinctual behavioural responses of zebrafish in repeated novel tank diving assays but does limit the associative learning capabilities.


Assuntos
Aprendizagem por Associação/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Cobre/toxicidade , Aprendizagem em Labirinto/efeitos dos fármacos , Memória Espacial/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , Animais , Carga Corporal (Radioterapia) , Cobre/metabolismo , Atividade Motora/efeitos dos fármacos , Poluentes Químicos da Água/metabolismo , Peixe-Zebra/metabolismo
14.
Environ Toxicol ; 35(1): 5-14, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31452338

RESUMO

Superoxide dismutase (SOD) acts as the first line of defense against reactive oxygen species (ROS) within cells. In the present study, we determined two novel CuZnSOD genes (designated as CeCSD1 and CeCSD2) from the toxicity-testing freshwater algae Closterium ehrenbergii and examined their structural features, phylogenetic relationships, and gene expression under exposure to different metals. Putative CeCSD1 (204 aa, 20.6 kDa) and CeCSD2 (155 aa, 15.3 kDa) proteins had conserved CuZnSOD family motifs and metal (Cu, Zn) binding sites, but different N-terminus structures, that is, CeCSD1 has a signal peptide to chloroplasts. Phylogenetic analysis of each protein revealed that C. ehrenbergii was well clustered with other green algae and plants. Real-time PCR results showed that the gene expression obviously increased with heavy metal exposure. In addition, excess copper considerably increased the SOD activity and ROS generation but decreased the photosynthetic efficiency in treated cells. These results suggest that CeCSDs are involved in the antioxidant defense system and can be regarded as potential biomarkers for monitoring metal contaminants in aquatic environments.


Assuntos
Closterium/efeitos dos fármacos , Cobre/toxicidade , Água Doce , Expressão Gênica/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Zinco/toxicidade , Antioxidantes/metabolismo , Closterium/enzimologia , Cobre/metabolismo , Estresse Oxidativo/genética , Fotossíntese/efeitos dos fármacos , Fotossíntese/genética , Filogenia , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo , Zinco/metabolismo
15.
Chemosphere ; 240: 124884, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31542586

RESUMO

Antibiotics and heavy metals are frequently detected simultaneously in water environment. In this study, the competitive adsorption behavior of tylosin (TYL) and sulfamethoxazole (SMX) on nano-hydroxyapatite modified biochar (nHAP@biochar) in accordance with Cu(II) in single, binary and ternary systems was investigated. The specific surface area of nHAP@biochar was 566.056 m2/g. The adsorption of TYL on nHAP@biochar reduced by 13.36%-41.04% or 9.92%-38.69% with Cu(II) and SMX in the solution, respectively. The suppression of SMX was stronger than Cu(II) on the adsorption of TYL when the SMX or Cu(II) was constant. The adsorption of SMX increased by 2.01-3.56 times in the present of Cu(II), while suppressed by TYL up to 42.30%. Due to the bridging of TYL or SMX between the nHAP@biochar and Cu(II) and destroying of bound water surrounded, the adsorption of Cu(II) increased to a greater extent. Electrostatic interaction and H-bond were the two main interactions between TYL, SMX and Cu(II) and nHAP@biochar. π-π interactions was also interaction between the SMX and nHAP@biochar.


Assuntos
Carvão Vegetal/química , Cobre/metabolismo , Durapatita/química , Nanopartículas/química , Sulfametoxazol/metabolismo , Tilosina/metabolismo , Poluentes Químicos da Água/metabolismo , Adsorção , Cobre/isolamento & purificação , Sulfametoxazol/isolamento & purificação , Tilosina/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos
16.
Sci Total Environ ; 700: 134510, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31629267

RESUMO

Manganese-oxidizing aerobic granular sludge (Mn-AGS) is a novel extension of AGS technology to treat arsenic (As) in organic wastewater. In this study, Mn-AGS was first applied to treat real wastewater (bottom ash leachates) containing high levels of As(III) and Cu(II) in a sequencing batch reactor (SBR) for 91 days. Influent and effluent As(III), As(V), Cu(II), as well as pH and chemical oxygen demand (COD) were monitored daily, and sludge was collected regularly for morphological observation, chemical characterization, and microbial analysis. The results indicated that As(III) and Cu(II) could be efficiently removed from wastewater (∼83% and ∼100%, respectively), but the performance was sensitive to pH variation, especially for As(III). The removed As and Cu were mostly bound to carbonates (60.2 ±â€¯2.0% and 70.0 ±â€¯0.6%, respectively) and Fe/Mn oxides (28.2 ±â€¯1.6% and 14.6 ±â€¯0.5%, respectively) in the final sludge. Influent As(III) was partially oxidized into As(V), and high fractions of As(V) were obtained in the Fe/Mn oxide-bound phase. Unexpectedly, microbial analysis revealed that community richness was only slightly changed when the influent was acidized (pH 4.0) but greatly reduced after the influent pH back to 6.0. It could be explained by that acid-fast bacteria rapidly grew after pH recovery and eliminated non-acid-fast bacteria. This work further supported the practical application of Mn-AGS to treat As(III)-containing organic wastewaters.


Assuntos
Arsênico/metabolismo , Cobre/metabolismo , Manganês/metabolismo , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo , Aerobiose , Arsênico/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise
17.
Sci Total Environ ; 700: 134529, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31693956

RESUMO

At a former wood preservation site contaminated with Cu, various phytomanagement options have been assessed in the last decade through physicochemical, ecotoxicological and biological assays. In a field trial at this site, phytomanagement with a crop rotation based on tobacco and sunflower, combined with the incorporation of compost and dolomitic limestone, has proved to be efficient in Cu-associated risk mitigation, ecological soil functions recovery and net gain of economic and social benefits. To demonstrate the long-term effectiveness and sustainability of phytomanagement, we assessed here the influence of this remediation option on the diversity, composition and structure of microbial communities over time, through a metabarcoding approach. After 9 years of phytomanagement, no overall effect was identified on microbial diversity; the soil amendments, notably the repeated compost application, led to shifts in soil microbial populations. This phytomanagement option induced changes in the composition of soil microbial communities, promoting the growth of microbial groups belonging to Alphaproteobacteria, many being involved in N cycling. Populations of Nitrososphaeria, which are crucial in nitrification, as well as taxa from phyla Planctomycetacia, Chloroflexi and Gemmatimonadetes, which are tolerant to metal contamination and adapted to oligotrophic soil conditions, decreased in amended phytomanaged plots. Our study provides an insight into population dynamics within soil microbial communities under long-term phytomanagement, in line with the assessment of soil ecological functions and their recovery.


Assuntos
Biodegradação Ambiental , Cobre/metabolismo , Helianthus/fisiologia , Microbiologia do Solo , Poluentes do Solo/metabolismo , Tabaco/fisiologia , Compostagem , Cobre/análise , Solo/química , Poluentes do Solo/análise
18.
Ecotoxicol Environ Saf ; 187: 109830, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31648074

RESUMO

A second intracellular copper/zinc superoxide dismutase (icCuZnSOD2) and manganese SOD (MnSOD) were cloned and characterized in Oxya chinensis. The open reading frame (ORF) of OcicCuZnSOD2 and OcMnSOD are 462 and 672 bp encoding 153 and 223 amino acids, respectively. OcicCuZnSOD2 contains two signature sequences, one potential N-glycosylation site, and seven copper/zinc binding sites. OcMnSOD includes a mitochondria targeting sequence of 7 amino acids at N-terminal, one signature sequence, two N-glycosylation sites, and four manganese binding sites. The secondary structure and homology model of OcicCuZnSOD2 include nine ß sheets, two Greek-key motifs, and one electrostatic loop. OcMnSOD contains nine α-helices and three ß-sheets. Phylogenetic analysis shows that OcMnSOD is evolutionarily conserved while OcicCuZnSOD2 may be gene duplication and is paralogous to OcicCuZnSOD1. OcMnSOD expressed widely in all tissues and developmental stages. OcicCuZnSOD2 showed testis-specific expression and expressed highest in the 5th-instar nymph and the adult. The optimum temperatures and pH values of the recombinant OcicCuZnSOD2 and OcMnSOD were 40 °C and 8.0. They were stable at 25-55 °C and at pH 5.0-12.0 and pH 6.0-12.0, respectively. The activity and mRNA expression of each OcSOD were assayed after chlorpyrifos treatments. Total SOD and CuZnSOD activities first increased then declined under chlorpyrifos stress. Chlorpyrifos induced the mRNA expression and activity of OcMnSOD as a dose-dependent manner and inhibited OcicCuZnSOD2 transcription. The role of each OcSOD gene in chlorpyrifos stress was investigated using RNAi and disc diffusion assay with Escherichia coli overexpressing OcSOD proteins. Silencing of OcMnSOD significantly increased ROS content in chlorpyrifos-exposed grasshoppers. Disc diffusion assay showed that the plates with E. coli overexpressing OcMnSOD had the smaller inhibition zones around the chlorpyrifos-soaked filter discs. These results implied that OcMnSOD played a significant role in defense chlorpyrifos-induced oxidative stress.


Assuntos
Clorpirifos/metabolismo , Gafanhotos/enzimologia , Proteínas de Insetos/fisiologia , Metais Pesados/metabolismo , Superóxido Dismutase/fisiologia , Animais , Cobre/metabolismo , Gafanhotos/classificação , Proteínas de Insetos/química , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Manganês/metabolismo , Filogenia , Superóxido Dismutase/química , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Zinco/metabolismo
19.
J Pharm Biomed Anal ; 177: 112857, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31557587

RESUMO

Age-related macular degeneration (AMD), the main cause of irreversible blindness in people over 60 years of age, is an eye disease that evolves with loss of central vision. Although AMD manifests itself in the eye, blood is continuously flowing through the macular region, such that potential alterations in this region could be reflected in the composition of whole blood or plasma/serum. Therefore, the potential clinical relevance of analysis of serum samples was assessed because of the low degree of invasiveness of blood sampling. 40 initial samples (20 from controls and 20 from patients with the dry form of AMD) have been analysed in this work to investigate the possible occurrence of homeostatic alterations of essential mineral elements caused by the disease. Both major (Na, Mg, P and K) and trace (Fe, Cu and Zn) essential mineral elements were determined in blood serum using single-collector ICP-mass spectrometry. Also, the isotopic composition of Cu (an element proposed to be directly involved in the onset of AMD) was determined using multi-collector ICP-mass spectrometry. Unexpected light Cu isotopic compositions in three individuals assumed as controls, resulted in a re-evaluation of their clinical information and a later exclusion due to pathologies initially not accounted for. In this pilot study, a significant alteration in the δ65Cu value has been found between the two final cohorts (AMD patients: n = 20; controls n = 17), with lower δ65Cu values (i.e. an enrichment in the light 63Cu isotope) in the case of AMD. Also, higher serum concentrations of the elements P and Zn were established in AMD at a systemic level.


Assuntos
Cobre/sangue , Degeneração Macular/diagnóstico , Isótopos de Fósforo/sangue , Isótopos de Zinco/sangue , Idoso , Idoso de 80 Anos ou mais , Cobre/metabolismo , Feminino , Humanos , Degeneração Macular/sangue , Degeneração Macular/metabolismo , Masculino , Espectrometria de Massas/métodos , Pessoa de Meia-Idade , Isótopos de Fósforo/metabolismo , Projetos Piloto , Isótopos de Zinco/metabolismo
20.
Ecotoxicol Environ Saf ; 190: 110105, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31884325

RESUMO

Copper (Cu) toxicity has a deleterious effect on plant growth, and different nitrogen (N) forms have significantly different impacts on the uptake and accumulation of heavy metals by plants. However, it remains unclear how excess Cu inhibits the growth of rice seedlings under different N forms. Here, we examined the mechanism of Cu toxicity inhibiting the growth of rice supplied with different N forms. Rice seedlings were grown in a nutrient solution with 0.81 mmol L-1 N, as ammonium (NH4+), nitrate (NO3-) and NH4+ + NO3-, or without N (0 N) in the presence of 0.2 µmol L-1 CuSO4 or 10 µmol L-1 CuSO4. The inhibition of shoot growth under excess Cu was more pronounced in plants that were supplied with NO3- than NH4+; such inhibition was not induced by higher Cu concentration in shoots. Applied with NO3- alone increased solution pH value up to 6.2, but supplied with NH4+ alone and NH4+ + NO3- decreased solution pH value to 4.0 and 4.2, respectively. The increment of solution pH reduced Cu concentration in shoots of rice supplied with NO3- alone. Copper toxicity decreased NO3- concentrations in rice seedlings that were supplied with NO3- alone but increased the NH4+ concentrations in plants that were supplied with NH4+ or NH4+ + NO3-. High Cu levels reduced the uptake of NO3- in roots by the analysis of net NO3- flux and NO3- assimilation enzymes activity. Under excess Cu, the transcript levels of OsNPF6.5, OsNPF2.2 and OsNPF2.4 genes were suppressed, while OsNRT2.1, OsNRT2.2 and OsNAR2.1 were raised in roots. In conclusion, Cu toxicity inhibits NO3- uptake and upward translocation by modulating the expression level of NO3- transporter genes. The reduction in the concentrations of NO3- and total N decreased shoot growth of rice seedlings when N was supplied as NO3-. Hence, rice seedlings supplied with NO3- had lower shoot biomass than those with NH4+ under Cu stress.


Assuntos
Cobre/toxicidade , Nitratos/metabolismo , Oryza/fisiologia , Poluentes do Solo/toxicidade , Compostos de Amônio/metabolismo , Transporte Biológico , Biomassa , Cobre/metabolismo , Nitratos/análise , Nitrogênio/metabolismo , Óxidos de Nitrogênio/metabolismo , Oryza/metabolismo , Raízes de Plantas/metabolismo , Plântula/crescimento & desenvolvimento
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