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1.
Physiol Plant ; 176(2): e14226, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38410873

RESUMO

Due to anthropogenic activities, environmental pollution of heavy metals/metalloids (HMs) has increased and received growing attention in recent decades. Plants growing in HM-contaminated soils have slower growth and development, resulting in lower agricultural yield. Exposure to HMs leads to the generation of free radicals (oxidative stress), which alters plant morpho-physiological and biochemical pathways at the cellular and tissue levels. Plants have evolved complex defense mechanisms to avoid or tolerate the toxic effects of HMs, including HMs absorption and accumulation in cell organelles, immobilization by forming complexes with organic chelates, extraction via numerous transporters, ion channels, signaling cascades, and transcription elements, among others. Nonetheless, these internal defensive mechanisms are insufficient to overcome HMs toxicity. Therefore, unveiling HMs adaptation and tolerance mechanisms is necessary for sustainable agriculture. Recent breakthroughs in cutting-edge approaches such as phytohormone and gasotransmitters application, nanotechnology, omics, and genetic engineering tools have identified molecular regulators linked to HMs tolerance, which may be applied to generate HMs-tolerant future plants. This review summarizes numerous systems that plants have adapted to resist HMs toxicity, such as physiological, biochemical, and molecular responses. Diverse adaptation strategies have also been comprehensively presented to advance plant resilience to HMs toxicity that could enable sustainable agricultural production.


Assuntos
Metaloides , Metais Pesados , Poluentes do Solo , Agricultura , Fenômenos Químicos , Metaloides/metabolismo , Metaloides/toxicidade , Metais Pesados/toxicidade , Plantas/metabolismo , Solo , Poluentes do Solo/toxicidade
2.
J Biol Chem ; 299(12): 105410, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37913906

RESUMO

Aquaporins can facilitate the passive movement of water, small polar molecules, and some ions. Here, we examined solute selectivity for the barley Nodulin 26-like Intrinsic Protein (HvNIP2;1) embedded in liposomes and examined through stopped-flow light scattering spectrophotometry and Xenopus laevis oocyte swelling assays. We found that HvNIP2;1 permeates water, boric and germanic acids, sucrose, and lactose but not d-glucose or d-fructose. Other saccharides, such as neutral (d-mannose, d-galactose, d-xylose, d-mannoheptaose) and charged (N-acetyl d-glucosamine, d-glucosamine, d-glucuronic acid) aldoses, disaccharides (cellobiose, gentiobiose, trehalose), trisaccharide raffinose, and urea, glycerol, and acyclic polyols, were permeated to a much lower extent. We observed apparent permeation of hydrated KCl and MgSO4 ions, while CH3COONa and NaNO3 permeated at significantly lower rates. Our experiments with boric acid and sucrose revealed no apparent interaction between solutes when permeated together, and AgNO3 or H[AuCl4] blocked the permeation of all solutes. Docking of sucrose in HvNIP2;1 and spinach water-selective SoPIP2;1 aquaporins revealed the structural basis for sucrose permeation in HvNIP2;1 but not in SoPIP2;1, and defined key residues interacting with this permeant. In a biological context, sucrose transport could constitute a novel element of plant saccharide-transporting machinery. Phylogenomic analyses of 164 Viridiplantae and 2993 Archaean, bacterial, fungal, and Metazoan aquaporins rationalized solute poly-selectivity in NIP3 sub-clade entries and suggested that they diversified from other sub-clades to acquire a unique specificity of saccharide transporters. Solute specificity definition in NIP aquaporins could inspire developing plants for food production.


Assuntos
Aquaporinas , Hordeum , Metaloides , Água , Animais , Aquaporinas/metabolismo , Glucosamina , Hordeum/metabolismo , Metaloides/metabolismo , Sacarose , Água/metabolismo
3.
Funct Plant Biol ; 50(11): 870-888, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37598713

RESUMO

Heavy metals and metalloids (HMs) contamination in the environment has heightened recently due to increasing global concern for food safety and human livability. Zinc (Zn2+ ) is an important nutrient required for the normal development of plants. It is an essential cofactor for the vital enzymes involved in various biological mechanisms of plants. Interestingly, Zn2+ has an additional role in the detoxification of HMs in plants due to its unique biochemical-mediating role in several soil and plant processes. During any exposure to high levels of HMs, the application of Zn2+ would confer greater plant resilience by decreasing oxidative stress, maintaining uptake of nutrients, photosynthesis productivity and optimising osmolytes concentration. Zn2+ also has an important role in ameliorating HMs toxicity by regulating metal uptake through the expression of certain metal transporter genes, targeted chelation and translocation from roots to shoots. This review examined the vital roles of Zn2+ and nano Zn in plants and described their involvement in alleviating HMs toxicity in plants. Moving forward, a broad understanding of uptake, transport, signalling and tolerance mechanisms of Zn2+ /zinc and its nanoparticles in alleviating HMs toxicity of plants will be the first step towards a wider incorporation of Zn2+ into agricultural practices.


Assuntos
Metaloides , Metais Pesados , Humanos , Zinco/metabolismo , Metaloides/metabolismo , Metais Pesados/toxicidade , Metais Pesados/análise , Metais Pesados/metabolismo , Plantas/genética , Solo
4.
Microbiol Spectr ; 11(4): e0062823, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37409940

RESUMO

The constant, ever-increasing antibiotic resistance crisis leads to the announcement of "urgent, novel antibiotics needed" by the World Health Organization. Our previous works showed a promising synergistic antibacterial activity of silver nitrate with potassium tellurite out of thousands of other metal/metalloid-based antibacterial combinations. The silver-tellurite combined treatment not only is more effective than common antibiotics but also prevents bacterial recovery, decreases the risk of future resistance chance, and decreases the effective concentrations. We demonstrate that the silver-tellurite combination is effective against clinical isolates. Further, this study was conducted to address knowledge gaps in the available data on the antibacterial mechanism of both silver and tellurite, as well as to give insight into how the mixture provides synergism as a combination. Here, we defined the differentially expressed gene profile of Pseudomonas aeruginosa under silver, tellurite, and silver-tellurite combination stress using an RNA sequencing approach to examine the global transcriptional changes in the challenged cultures grown in simulated wound fluid. The study was complemented with metabolomics and biochemistry assays. Both metal ions mainly affected four cellular processes, including sulfur homeostasis, reactive oxygen species response, energy pathways, and the bacterial cell membrane (for silver). Using a Caenorhabditis elegans animal model we showed silver-tellurite has reduced toxicity over individual metal/metalloid salts and provides increased antioxidant properties to the host. This work demonstrates that the addition of tellurite would improve the efficacy of silver in biomedical applications. IMPORTANCE Metals and/or metalloids could represent antimicrobial alternatives for industrial and clinical applications (e.g., surface coatings, livestock, and topical infection control) because of their great properties, such as good stability and long half-life. Silver is the most common antimicrobial metal, but resistance prevalence is high, and it can be toxic to the host above a certain concentration. We found that a silver-tellurite composition has antibacterial synergistic effect and that the combination is beneficial to the host. So, the efficacy and application of silver could increase by adding tellurite in the recommended concentration(s). We used different methods to evaluate the mechanism for how this combination can be so incredibly synergistic, leading to efficacy against antibiotic- and silver-resistant isolates. Our two main findings are that (i) both silver and tellurite mostly target the same pathways and (ii) the coapplication of silver with tellurite tends not to target new pathways but targets the same pathways with an amplified change.


Assuntos
Anti-Infecciosos , Metaloides , Animais , Nitrato de Prata/farmacologia , Nitrato de Prata/metabolismo , Pseudomonas aeruginosa/metabolismo , Antibacterianos/química , Anti-Infecciosos/metabolismo , Metaloides/metabolismo , Testes de Sensibilidade Microbiana
5.
J Exp Bot ; 74(11): 3286-3299, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-36861339

RESUMO

Soil contamination with trace metals and metalloids can cause toxicity to plants and threaten food safety and human health. Plants have evolved sophisticated mechanisms to cope with excess trace metals and metalloids in soils, including chelation and vacuolar sequestration. Sulfur-containing compounds, such as glutathione and phytochelatins, play a crucial role in their detoxification, and sulfur uptake and assimilation are regulated in response to the stress of toxic trace metals and metalloids. This review focuses on the multi-level connections between sulfur homeostasis in plants and responses to such stresses, especially those imposed by arsenic and cadmium. We consider recent progress in understanding the regulation of biosynthesis of glutathione and phytochelatins and of the sensing mechanism of sulfur homeostasis for tolerance of trace metals and metalloids in plants. We also discuss the roles of glutathione and phytochelatins in controlling the accumulation and distribution of arsenic and cadmium in plants, and possible strategies for manipulating sulfur metabolism to limit their accumulation in food crops.


Assuntos
Arsênio , Metaloides , Humanos , Cádmio/metabolismo , Arsênio/metabolismo , Metaloides/metabolismo , Fitoquelatinas/metabolismo , Glutationa/metabolismo , Produtos Agrícolas/metabolismo , Enxofre/metabolismo
6.
J Integr Plant Biol ; 65(2): 570-593, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36546407

RESUMO

Plants take up a wide range of trace metals/metalloids (hereinafter referred to as trace metals) from the soil, some of which are essential but become toxic at high concentrations (e.g., Cu, Zn, Ni, Co), while others are non-essential and toxic even at relatively low concentrations (e.g., As, Cd, Cr, Pb, and Hg). Soil contamination of trace metals is an increasing problem worldwide due to intensifying human activities. Trace metal contamination can cause toxicity and growth inhibition in plants, as well as accumulation in the edible parts to levels that threatens food safety and human health. Understanding the mechanisms of trace metal toxicity and how plants respond to trace metal stress is important for improving plant growth and food safety in contaminated soils. The accumulation of excess trace metals in plants can cause oxidative stress, genotoxicity, programmed cell death, and disturbance in multiple physiological processes. Plants have evolved various strategies to detoxify trace metals through cell-wall binding, complexation, vacuolar sequestration, efflux, and translocation. Multiple signal transduction pathways and regulatory responses are involved in plants challenged with trace metal stresses. In this review, we discuss the recent progress in understanding the molecular mechanisms involved in trace metal toxicity, detoxification, and regulation, as well as strategies to enhance plant resistance to trace metal stresses and reduce toxic metal accumulation in food crops.


Assuntos
Metaloides , Metais Pesados , Poluentes do Solo , Humanos , Metais Pesados/análise , Metais Pesados/metabolismo , Metais Pesados/toxicidade , Metaloides/metabolismo , Poluentes do Solo/análise , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade , Solo/química , Plantas/metabolismo
7.
Environ Microbiol ; 24(11): 5139-5150, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35880613

RESUMO

Methylarsenite [MAs(III)] is a highly toxic arsenical produced by some microbes as an antibiotic. In this study, we demonstrate that a PadR family transcriptional regulator, PadRars , from Azospirillum halopraeferens strain Au 4 directly binds to the promoter region of the arsenic resistance (ars) operon (consisting of padRars , arsV, and arsW) and represses transcription of arsV and arsW genes involved in MAs(III) resistance. Quantitative reverse transcriptase PCR and transcriptional reporter assays showed that transcription of the ars operon is induced strongly by MAs(III) and less strongly by arsenite and antimonite. Electrophoretic mobility shift assays with recombinant PadRars showed that it represses transcription of the ars operon by binding to two inverted-repeat sequences within the ars promoter. PadRars has two conserved cysteine pairs, Cys56/57 and Cys133/134; mutation of the first pair to serine abolished the transcriptional response of the ars operon to trivalent metalloids, suggesting that Cys56/57 form a binding site for trivalent metalloids. Either C133S or C134S derivative responses to MAs(III) but not As(III) or Sb(III), suggesting that it is a third ligand to trivalent metalloids. PadRars represents a new type of repressor proteins regulating transcription of an ars operon involved in the resistance to trivalent metalloids, especially MAs(III).


Assuntos
Arsênio , Metaloides , Regulação Bacteriana da Expressão Gênica , Metaloides/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Óperon , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Arsênio/metabolismo
8.
Chemosphere ; 303(Pt 3): 135196, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35659937

RESUMO

Heavy metal/metalloids (HMs) are among the primary soil pollutants that limit crop production worldwide. Plants grown in HM contaminated soils exhibit reduced growth and development, resulting in a decrease in crop production. The exposure to HMs induces plant oxidative stress due to the formation of free radicals, which alter plant morphophysiological and biochemical mechanisms at cellular and tissue levels. When exposed to HM toxicity, plants evolve sophisticated physiological and cellular defense strategies, such as sequestration and transportation of metals, to ensure their survival. Plants also have developed efficient strategies by activating signaling pathways, which induce the expression of HM transporters. Plants either avoid the uptake of HMs from the soil or activate the detoxifying mechanism to tolerate HM stress, which involves the production of antioxidants (enzymatic and non-enzymatic) for the scavenging of reactive oxygen species. The metal-binding proteins including phytochelatins and metallothioneins also participate in metal detoxification. Furthermore, phytohormones and their signaling pathways also help to regulate cellular activities to counteract HM stress. The excessive levels of HMs in the soil can contribute to plant morpho-physiological, biochemical, and molecular alterations, which have a detrimental effect on the quality and productivity of crops. To maintain the commercial value of fruits and vegetables, various measures should be considered to remove HMs from the metal-polluted soils. Bioremediation is a promising approach that involves the use of tolerant microorganisms and plants to manage HMs pollution. The understanding of HM toxicity, signaling pathways, and tolerance mechanisms will facilitate the development of new crop varieties that help in improving phytoremediation.


Assuntos
Metaloides , Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , Metaloides/metabolismo , Metais Pesados/análise , Plantas/metabolismo , Solo , Poluentes do Solo/análise
9.
Physiol Plant ; 174(3): e13687, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35514154

RESUMO

Metalloids in plants have diverse physiological effects. From being essential to beneficial to toxic, they have significant effects on many physiological processes, influencing crop yield and quality. Aquaporins are a group of membrane channels that have several physiological substrates along with water. Metalloids have emerged as one of their important substrates and they are found to have a substantial role in regulating plant metalloid homeostasis. The present review comprehensively details the multiple isoforms of aquaporins having specificity for metalloids and being responsible for their influx, distribution or efflux. In addition, it also highlights the usage of aquaporin-mediated transport as a selection marker in toxic screens and as tracer elements for closely related metalloids. Therefore, aquaporins, with their imperative contribution to the regulation of plant growth, development and physiological processes, need more research to unravel the metalloid trafficking mechanisms and their future applications.


Assuntos
Aquaporinas , Metaloides , Aquaporinas/metabolismo , Transporte Biológico , Metaloides/metabolismo , Proteínas de Plantas/metabolismo , Plantas/metabolismo
10.
Sci Total Environ ; 819: 153144, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35038542

RESUMO

Siderophores are small molecular weight iron scavengers that are mainly produced by bacteria, fungi, and plants. Recently, they have attracted increasing attention because of their potential role in environmental bioremediation. Although siderophores are generally considered to exhibit high specificity for iron, they have also been reported to bind to various metal and metalloid ions. This unique ability allows siderophores to solubilise and mobilise heavy metals and metalloids from soil, thereby facilitating their bioremediation. In addition, because of their redox nature, they can mediate the production of reactive oxygen species (ROS), and thus promote the biodegradation of organic contaminants. The aim of this review is to summarise the existing knowledge on the developed strategies of siderophore-assisted bioremediation of metals, metalloids, and organic contaminants. Additionally, this review also includes the biosynthesis and classification of microbial and plant siderophores.


Assuntos
Metaloides , Metais Pesados , Biodegradação Ambiental , Ferro/metabolismo , Metaloides/metabolismo , Metais Pesados/metabolismo , Sideróforos/metabolismo
11.
Zebrafish ; 18(4): 252-264, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34227897

RESUMO

Metals and metalloids are integral to biological processes and play key roles in physiology and metabolism. Nonetheless, overexposure to some metals or lack of others can lead to serious health consequences. In this study, eight zebrafish facilities collaborated to generate a multielement analysis of their centralized recirculating water systems. We report a first set of average concentrations for 46 elements detected in zebrafish facilities. Our results help to establish an initial baseline for trouble-shooting purposes, and in general for safe ranges of metal concentrations in recirculating water systems, supporting reproducible scientific research outcomes with zebrafish.


Assuntos
Metaloides , Poluentes Químicos da Água , Animais , Metaloides/análise , Metaloides/metabolismo , Água , Poluentes Químicos da Água/análise , Peixe-Zebra/metabolismo
12.
Metallomics ; 13(8)2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34302346

RESUMO

With the introduction of tandem mass spectrometry to inductively coupled plasma mass spectrometry (ICPMS/MS), the potential for non-targeted elemental metabolomic analysis has been expanded to many non-metals of pivotal biological importance. Arsenic and selenium are trace elements that share chemical similarity with the non-metals phosphorus and sulfur, respectively, and this similarity can be exploited to gain more insight into the incompletely understood biological significance of these metalloids and the evolution of their biochemical pathways. As a proof of concept, we show the applicability of HPLC-ICPMS/MS for non-targeted and parallel speciation analysis of arsenic, selenium, phosphorus, and sulfur in mushrooms-metabolically diverse organisms. Incredibly contrasting levels of diversity were found in the metabolomic profiles of the four investigated elements among the various species along with sharp discrepancies among related elements (e.g. phosphorous vs. arsenic) in certain mushroom species. The present work shows that ICPMS/MS offers a new dimension in non-targeted metabolomic analysis and enables a unique comparative approach in investigating and tracking the biochemistry of related elements in moderately complex organisms.


Assuntos
Agaricales/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Metaloides/análise , Metais/análise , Espectrometria de Massas em Tandem/métodos , Metaloides/química , Metaloides/metabolismo , Metais/química , Metais/metabolismo
13.
Ecotoxicol Environ Saf ; 215: 112147, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33756294

RESUMO

The intensive shift on land cover by anthropogenic activities have led to changes in natural habitats and environmental contamination, which can ultimately impact and threat biodiversity and ecosystem services, such as pollination. The aim of this study was to evaluate the effect of native forest and human-modified land covers on the concentrations of chemical elements accumulated in the neotropical pollinator bee T. angustula. Eight landscapes, within an Ecological Corridor in the State of São Paulo, Brazil, with gradients of forest cover, spatial heterogeneity and varying land covers were used as sampling unities. Bees collected in traps or through actives searches had the concentration of 21 chemical elements determined by ICP-MS. Results show a beneficial effect of forested areas on the concentrations of some well-known toxic elements accumulated in bees, such as Hg, Cd, and Cr. Multivariate Redundancy Analysis (RDA) suggests road as the most important driver for the levels of Cr, Hg, Sb, Al, U, As, Pb and Pt and bare soil, pasture and urban areas as the landscape covers responsible for the concentrations of Zn, Cd, Mn, Mg, Ba and Sr in bees. The results reinforce the potential use of T. angustula bees as bioindicators of environmental quality and also show that these organisms are being directly affected by human land use, offering potential risks for the Neotropical ecosystem. Our study sheds light on how land covers (native forest and human-modified) can influence the levels of contaminants in insects within human-dominated landscapes. The generation of predictions of the levels of toxic metals and metalloids based on land use can both contribute to friendly farming planning as well as to support public policy development on the surrounding of protected areas and biodiversity conservation hotspots.


Assuntos
Abelhas/fisiologia , Monitoramento Ambiental , Metaloides/metabolismo , Metais/metabolismo , Agricultura , Animais , Biodiversidade , Brasil , Ecossistema , Florestas , Intoxicação por Metais Pesados , Humanos , Polinização , Solo
14.
Ecotoxicol Environ Saf ; 215: 112165, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33773149

RESUMO

BACKGROUND: Exposure to metals/metalloids, including essential and nonessential elements, has been associated to male reproductive health in animals. However, findings from human studies are inconsistent. OBJECTIVES: To investigate the impact of exposure to multiple metals/metalloids at environmental levels on the conventional human semen-quality parameters. MATERIALS AND METHODS: Men living in rural or industrial areas were recruited by personalized letters. No exclusion criteria were applied. Each man provided one semen sample and one blood sample. We analyzed the semen sample both to determine conventional sperm parameters (concentration, progressive motility and normal forms) and to quantify lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As), nickel (Ni), vanadium (V) and selenium (Se) levels. The levels of these metals/metalloids were also quantified in venous blood and spermatozoa samples. Associations between the blood/seminal plasma metal/metalloid levels and semen quality parameters were assessed using confounder adjusted logistic regression models. Correlation and interactions between blood/seminal plasma and semen metal/metalloid levels were investigated using the Spearman's correlation. RESULTS: We found a positive association of seminal plasma cadmium level with lower Total count (OR = 4.48, 95%CI 0.25-80); whereas lead (OR = 4.51, 95%CI 0.86-23) and cadmium (OR = 3.45, 95%CI 0.77-16) seminal plasma levels had a positive association with progressive sperm motility. Overall, these associations remained suggestive after adjustment, though statistically unstable risks. Finally, we found weak interactions between beneficial effects of Se and detrimental ones only for Cd and Pb blood level on sperm concentration, total sperm count and progressive sperm motility. CONCLUSIONS: Our findings suggest that environmental exposure to Pb and Cd contributes to a decline in human semen quality, whereas Se can have beneficial effects. Measurements of metals/metalloids in the seminal fluid may be more predictable of semen quality than conventional blood measurements.


Assuntos
Exposição Ambiental , Metaloides/toxicidade , Metais/toxicidade , Sêmen/efeitos dos fármacos , Adulto , Arsênio/sangue , Líquidos Corporais , Cádmio/farmacologia , Estudos Transversais , Humanos , Masculino , Mercúrio , Metaloides/metabolismo , Metais/metabolismo , Níquel/farmacologia , Selênio , Análise do Sêmen , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Vanádio
15.
Ecotoxicol Environ Saf ; 208: 111602, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396122

RESUMO

The Tablas de Daimiel National Park (TDNP) is a floodplain ecosystem in central Spain with a potential risk of heavy metal and metalloid pollution. The objective of this study was to know the accumulation of arsenic (As), cadmium (Cd), mercury (Hg), lead (Pb), and selenium (Se) in muscle of six species of freshwater fish from the floodplain of TDNP. We obtained muscle samples of Cyprinus carpio (n = 89); Squalius pyrenaicus (n = 16); Ameiurus melas (n = 9); Lepomis gibbosus (n = 8); Micropterus salmoides (n = 6) and Carassius auratus (n = 5). A. melas, which is a predatory species, had significantly higher Hg concentrations than omnivorous or herbivorous species (i.e. C. carpio). On the contrary, A. melas showed lower concentrations of As, Pb and Se than omnivorous species (i.e. S. pyrenaicus and L. gibbosus ). The concentration of Hg was positively associated with fish size in C. carpio and A. melas. Some individuals of C. carpio (5.7%) and S. pyrenaicus (12.5%) showed Pb muscle concentrations above the maximum residue levels established by the European legislation for human consumers. The observed muscle Se concentrations can be associated with adverse effects on fish such as blood changes, reduced growth, mortality of juveniles and reproductive failure. The accumulation of Se in this floodplain located in a seleniferous area and the contamination produced by spent Pb shot pellets used for hunting in the past are discussed as potential sources of the elevated levels of these two elements in fish from this floodplain wetland.


Assuntos
Carpas/metabolismo , Monitoramento Ambiental/métodos , Metaloides/metabolismo , Metais Pesados/metabolismo , Parques Recreativos , Poluentes Químicos da Água/metabolismo , Animais , Bioacumulação , Carpas/crescimento & desenvolvimento , Ecossistema , Água Doce/química , Sedimentos Geológicos/química , Humanos , Metaloides/análise , Metais Pesados/análise , Músculos/química , Músculos/efeitos dos fármacos , Músculos/metabolismo , Espanha , Poluentes Químicos da Água/análise , Áreas Alagadas
16.
Ecotoxicol Environ Saf ; 208: 111493, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33120261

RESUMO

In San Luis Potosí, Mexico, the exploitation of minerals has historically been carried out as an activity that has left in its path environmental liabilities, with high concentrations of heavy metals. These metals have undergone weathering by rain and wind and have moved closer to inhabited locations as is the case of Cerro de San Pedro (CSP) and Villa de la Paz (VDP). The objective of this study is to show the biological alteration of soils due to the presence of heavy metals and metalloids like Cadmium (Cd), Copper (Cu), Lead (Pb) and Arsenic (As) and to find the relationship between contamination and risk indexes. Soil samples were obtained from sites with historical records of mining activity and their surroundings. Several analyses were performed, such as pH levels, organic matter, electrical conductivity, clays, heavy metals and As. Moreover, Community Level Physiological profiling (CLPP) were conducted. The obtained evidence showed high levels of contamination by As and heavy metals in both sites (CSP: 6485.1 mg/Kg of Pb and pH of 4.4; VDP: 7188.2 mg/Kg of As and pH of 7.8). According to the Metal Pollution Index (MPI), 607.0 in CSP and 1050.5 in VDP, presented a high environmental risk, apart from, risk to human health (SQGQI) 35.8 in CSP and 131.5 in VDP. At the same time, CLPPs showed that microbiological communities were selective in taking up substrate groups, in the following order: Carbohydrates > Polymers > Carboxylic acids > Amino acids > Amines/Amides. However, a positive correlation in CSP was only found between both indexes and Amines/Amides (r = 0.46, p < 0.05), and in VDP the D-Galactonic acid-γ-Lactone with the MPI (r = 0.49, p < 0.05), and with the SQGQI (r = 0.45, p < 0.05). Although this behavior was not homogeneous, it was possible to find negative correlations between both indexes and the AWCD with other substrates, influenced by the physicochemical characteristics presented in each studied site. Consequently, according to our findings, a combined effect between the physicochemical characteristics, As, and heavy metals took place, on the metabolic activity, causing alterations to soil functions.


Assuntos
Bactérias/metabolismo , Carbono/metabolismo , Metaloides/metabolismo , Metais Pesados/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , México , Mineração
18.
Environ Geochem Health ; 43(1): 77-89, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32728949

RESUMO

Metal(loid) pollution of soils has important negative effects on the environment and human health. For the rehabilitation of these soils, some eco-innovative strategies, such as phytoremediation, could be chosen. This practice could establish a plant cover to reduce the toxicity of the pollutants and stabilize the soil, preventing soil erosion and water leaching; this technique is called phytoremediation. For this, plants need to be tolerant to the pollutants present; thus, phytoremediation can have better outcomes if endemic species of the polluted area are used. Finally, to further improve phytoremediation success, amendments can be applied to ameliorate soil conditions. Different amendments can be used, such as biochar, a good metal(loid) immobilizer, compost, a nutrient-rich product and iron sulfate, an efficient arsenic immobilizer. These amendments can either be applied alone or combined for further positive effects. In this context, a mesocosm experiment was performed to study the effects of three amendments, biochar, compost and iron sulfate, applied alone or combined to a former mine technosol, on the soil properties and the phytoremediation potential of two endemic species, Alnus sp. and Betula sp. Results showed that the different amendments reduced soil acidity and decreased metal(loid) mobility, thus improving plant growth. Both species were able to grow on the amended technosols, but alder seedlings had a much higher growth compared to birch seedlings. Finally, the combination of compost with biochar and/or iron sulfate and the establishment of endemic alder plants could be a solution to rehabilitate a former mine technosol.


Assuntos
Alnus/metabolismo , Betula/metabolismo , Mineração , Poluentes do Solo/metabolismo , Alnus/crescimento & desenvolvimento , Betula/crescimento & desenvolvimento , Biodegradação Ambiental , Carvão Vegetal/metabolismo , Compostagem , Compostos Ferrosos/metabolismo , Humanos , Metaloides/metabolismo , Metais/metabolismo , Plântula/crescimento & desenvolvimento
19.
Nat Prod Rep ; 37(9): 1262-1283, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32426792

RESUMO

Covering: up to 2019 Siderophores are natural products which have attracted interest due to their ability to bind metal ions with high affinities. This review considers the complex formation of these natural chelators with all kinds of different metal and metalloid ions and links their chelating properties to potential biotechnological applications and towards environmental context.


Assuntos
Bactérias/metabolismo , Produtos Biológicos/metabolismo , Quelantes/metabolismo , Metais/metabolismo , Biodegradação Ambiental , Produtos Biológicos/farmacologia , Técnicas Biossensoriais , Quelantes/farmacologia , Metaloides/metabolismo
20.
Ecotoxicol Environ Saf ; 195: 110466, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32200145

RESUMO

Remediation of metal(loid) polluted soils is an important area of research nowadays. In particular, one remediation technique is much studied, phytomanagement. Phytomanagement combines amendment application and plant growth in order to reduce the risk posed by contaminants. Salicaceae plants showed tolerance towards metal(loid)s and the ability to accumulate high amounts of metal(loid)s in their tissue. Amendments are often applied to counterbalance the reduced soil fertility and high metal(loid) concentrations. Two amendments gathered attention over the last decades, biochar (product of biomass pyrolysis), which can be activated for better effects, and redmud (by-product of alumina production). Those two amendments showed ability to improve soil conditions and thus plant growth, although few studied their combined application. Moreover, since metal(loid)s are known to induce the overproduction of reactive oxygen species, it is important to measure the level of oxidative stress in the plant, to which plants respond using enzymatic and non-enzymatic systems. But no studies evaluate the response of Salicaceae plants to metal(loid) stress and amendment application at the biochemical level in a real soil condition. Therefore, a mesocosm study was set up to evaluate the effect of amending a mine soil with redmud combined to diverse biochars on the soil properties and Salix triandra growth, metal(loid) accumulation and stress marker levels. Results showed that all amendment combinations improved the soil fertility, reduced metal(loid) mobility and thus ameliorated Salix triandra growth, which accumulated metal(loid)s mainly in its roots. Moreover, among the different amendment combinations, Salix triandra plants still suffered from oxidative stress when grown on PG soil amended with redmud and chemical activated carbon, showing elevated levels of phenolic compounds and salicinoids and important antioxidant and enzymatic activities. Finally, one treatment showed levels of these stress markers similar or lower than the control, the combination of redmud with steam activated carbon. In conclusion, this treatment seemed a good solution in a phytomanagement strategy using Salix triandra, improving soil conditions and plant growth and reducing oxidative stress level in the plant roots.


Assuntos
Carvão Vegetal , Metaloides/metabolismo , Metais/metabolismo , Estresse Oxidativo , Salix/metabolismo , Poluentes do Solo/metabolismo , Óxido de Alumínio , Biodegradação Ambiental , Metaloides/toxicidade , Metais/toxicidade , Salix/efeitos dos fármacos , Salix/crescimento & desenvolvimento , Solo/química , Poluentes do Solo/toxicidade
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