Copper Toxicity Research Articles

Single and mixture toxicity of cadmium and copper to swim bladder in early life stages of Japanese medaka (Oryzias latipes).

Toxicity observed in aquatic ecosystems often cannot be explained by the action of a single pollutant. Likewise, evaluation standards formulated by a single effect cannot truly reflect the environmental quality requirements. The study of mixtures is needed to provide environmental relevance and knowledge of combined toxicity. In this study, the embryos of Japanese medaka (Oryzias latipes) were treated with individual and binary mixture of copper (Cu) and cadmium (Cd) until 12days post-fertilization (dpf). Hatching, mortality, development, histology and gene expression were assessed. Our results showed that the highest concentration mixture of Cd (10mg/L) and Cu (1mg/L) affected survival, hatching time and hatching success. Occurrence of uninflated swim bladder was the highest (value) with exposure to 10mg/L Cd. Swim bladder was commonly over-inflated in a mixture (0.1mg/L Cd + 1.0mg/L Cu) exposure. Individuals exposed to the mixture (0.1 Cd + 1.0 Cu mg/L) showed up to a 7.69% increase in swim bladder area compared to the control group. The mixtures containing 0.1 or 10mg/L Cd, each with 1.0mg/L Cu resulted in significantly increased of Pbx1b expression, higher than any Cd or Cu alone (p < 0.01). In the co-exposure group (0.1/10 Cd + 1.0 Cu mg/L), Pbx1b expression was found at 12dpf but not 7dpf in controls. Higher concentrations of Cd may progressively reduce Pbx1b expression, potentially explaining why 75% of individuals in the 10mg/L Cd group failed to inflate their swim bladders. Additionally, the swim bladder proved to be a valuable bio-indicator for biological evaluation.

Dual-color photoluminescence modulation of zero-dimensional hybrid copper halide microcrystals.

Zero-dimensional hybrid copper(I) halides (HCHs) are attractive due to their interesting photoluminescence (PL) properties and the high abundance and low toxicity of copper. In this study, we report green-red dual emission from rhombic 1-butyl-1-methyl piperidinium copper bromide [(Bmpip)2Cu2Br4] microcrystals (MCs) prepared on borosilicate glass. The structure and elemental composition of the MCs are characterized by single crystal X-ray diffraction analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Interestingly, MCs prepared on an ITO-coated glass plate show an intense green emission compared to the dual emission on a bare glass or plastic substrate. Furthermore, the intensity of the green emission from the MC is enormously increased by powdering using a conductive material, suggesting the deactivation of the red-emitting state by a charge transfer interaction with the conductor. These findings open a new strategy to suppress the self-trapping of excitons by longitudinal optical phonons and control the dual emitting states in HCHs.

Copper-Induced InVivo Gene Amplification in Budding Yeast.

In the biotechnological industry, multicopy gene integration represents an effective strategy to maintain a high-level production of recombinant proteins and to assemble multigene biochemical pathways. In this study, we developed copper-induced invivo gene amplification in budding yeast for multicopy gene expressions. To make copper as an effective selection pressure, we first constructed a copper-sensitive yeast strain by deleting the CUP1 gene encoding a small metallothionein-like protein for copper resistance. Subsequently, the reporter gene fused with a proline-glutamate-serine-threonine-destabilized CUP1 was integrated at the δ sites of retrotransposon (Ty) elements to counter the copper toxicity at 100 μM Cu2+. We further demonstrated the feasibility of modulating chromosomal rearrangements for increased protein expression under higher copper concentrations. In addition, we also demonstrated a simplified design of integrating the expression cassette at the CUP1 locus to achieve tandem duplication under high concentrations of copper. Taken together, we envision that this method of copper-induced invivo gene amplification would serve as a robust and useful method for protein overproduction and metabolic engineering applications in budding yeast.

Alterations in Astrocyte Subpopulations in Glioma and Identification of Cuproptosis-Related Genes Using Single-Cell RNA Sequencing.

Mitochondrial metabolism is essential for energy production and the survival of brain cells, particularly in astrocytes. Cuproptosis is a newly identified form of programmed cell death that occurs due to the disruption of mitochondrial metabolism caused by excessive copper toxicity. However, the relationship between cuproptosis-related genes (CRGs) in the tumor microenvironment (TME) and the prognosis of gliomas remains unclear. In this study, we utilized 32,293 cells obtained from three in-house single-cell RNA sequencing (scRNA-seq) datasets, along with 6,148 cells acquired from the Chinese Glioma Genome Atlas (CGGA) involving 14 glioma patients, to identify and validate the TME of gliomas. Based on an analysis of 32,293 single cells, we investigated intra-tumor heterogeneity, intercellular communication, and astrocyte differentiation trajectories in gliomas. Our findings revealed that the TGFβ signaling pathway exhibited a higher relative strength in astrocyte subpopulations. Additionally, we identified a novel three-gene signature (CDKN2A, SOX2, and MPC1) was identified for prognostic prediction. Furthermore, glioma patients with a high-risk score demonstrated poorer overall survival (OS) compared to those with a low-risk score in both training and testing datasets (P training set < 0.001; P test set = 0.037). Our study revealed the prognostic value of the CRGs in astrocytes exhibiting tumor immunosuppressive characteristics in glioma. We established a novel three-gene prognostic model that offers new insights into the prognosis and treatment strategies for gliomas.

Using the sorption properties of diatomite from the Aktobe deposit in improving the quality of drinking water in Western Kazakhstan

The paper describes the results of monitoring studies of the quality of tap water in the city of Uralsk. A solution was found to use natural reserves of the mineral diatomite in the purification of drinking water. The natural sorbent diatomite was modified with hydrochloric acid before testing. Natural and modified diatomite samples were studied using X-ray fluorescence analysis and electron microscopy. In acid-activated diatomite, the specific surface area and porosity increase by 2.5 times. Xray fluorescence analysis of the elemental composition showed an increase in the silicon content in the sorbent. Organoleptic and physicochemical properties were studied in the original and diatomite-treated water: turbidity, taste, smell, color, hardness, permanganate oxidation, pH, iron and copper ions. The efficiency of sorption with respect to heavy metals was tested using the model toxicant copper sulfate. Determinations of copper and iron ions were carried out using the atomic spectrometry method. Hardness, permanganate oxidation, pH and organoleptic parameters were determined by standard methods. Treatment of water with natural and modified diatomite made it possible to significantly reduce water pollution according to the studied parameters. Filtering water with a modified diatomite sorbent allows you not only to purify water from unwanted impurities, but also to adjust its salt composition due to the intake of silicon. Based on the results of the work, we can conclude that, compared to natural, modified diatomite has higher adsorption properties in relation to copper and iron cations, increases pH, and also contributes to more effective water purification from unwanted impurities.

Non-Metallic and Metallic Toxicant Exposures from Personal Care Products in Indonesian Male and Female Medical Students

Students can gain various benefits from their daily personal care products. However, the chemicals contained in these products may have adverse health effects. Regardless the inspection performed by regulatory agencies on these products, the products circulating in the market may still contain toxicants thus may jeopardize their safety for use. This study evaluated toxicant ingredients contained in personal care products used by male and female college students. This study was conducted from September to December 2022 on 23 male and 46 female college students of the Faculty of Medicine, Universitas Andalas, Indonesia. Data were collected using a 69-items validated questionnaire. Results were then presented as a distribution of products used categorized by body areas and potentially toxic metallic and non-metallic ingredients identified from their labels. Female college students used at least 10 personal care products, with a median of 19 products. Male students used at least four products and a median of eight products. Investigation on the label of skin, hair, eye, dental and oral, lips, and nail personal care products demonstrated the presence of metallic and non-metallic toxicants. Five metallic toxicants (aluminum, titanium, zinc, copper, and chromium) and 15 non-metallic toxicants (triclosan, talc, fragrance, parabens, butylated hydroxyanisole, butylated hydroxytoluene, diethanolamine, triethanolamine, butylene glycol, propylene glycol, polyethylene glycol, phthalates, benzophenone-3, acetone, and fluoride) were identified. Thus, numerous toxicants are present in marketed personal care products, and females are exposed more than males to these toxicants. Consumers need to be more critical in their choice of personal care products.

Comparative subchronic toxicity of copper and a tertiary copper mixture to early life stage rainbow trout (Oncorhynchus mykiss): impacts on growth, development, and histopathology.

This research aimed to characterize and compare the subchronic impacts of Cu to a Cu, Cd, and Zn mixture in early life stages of rainbow trout (Oncorhynchus mykiss) by examining uptake, survival, growth, development, and histopathology parameters. To accomplish this, rainbow trout were exposed for 31 days from eyed embryos to the swim-up fry life stage to waterborne Cu (31, 47, 70, and 104 μg/L) individually or as mixture containing Cd (4.1, 6.2, 9.3, and 14 μg/L) and Zn (385, 578, 867, and 1300 μg/L). Exposures elicited pronounced effects on survival when Cu was administered as a mixture (LC25 = 32.9 μg/L Cu) versus individually (LC25 = 46.3 μg/L Cu). Mixtures of Cu, Cd, and Zn also elicited more pronounced sublethal toxicity relative to equivalent Cu treatments with respect to reduced yolk sac resorption and increased incidence and/or severity of gill, liver, and kidney lesions. Our findings of reduced body weight (EC10, Cu = 55.0 μg/L Cu; EC10, Cu+Cd+Zn = 58.9 μg/L Cu), yolk sac resorption (LOECCu = 70 μg/L Cu; LOECCu+Cd+Zn = 70 μg/L Cu), coelomic fat (LOECCu = 47 μg/L Cu; LOECCu+Cd+Zn = 70 μg/L Cu), and increased hepatocellular cytoplasmic vacuolation (LOECCu = 70 μg/L Cu; LOECCu+Cd+Zn = 47 μg/L Cu) collectively indicate a complicated metabolic interference by metals in exposed fish. These lethal and sublethal effects observed in the laboratory could translate to reduced survival and fitness of wild salmonid populations inhabiting waterbodies receiving wastewater or runoff containing multiple metals at elevated concentrations.

Protective Effects of Sanyar Prebiotic on Immunity and Tissue Changes of Common Carp (Cyprinus carpio) Exposed to CuSO4 Stress

Prebiotics, as feed additives, can activate the antioxidant and immune systems of fish and significantly improve the survival of aquaculture animals in stressful conditions. The exposure of fish to copper sulfate leads to oxidative stress, suppression of the immune system, and destruction of vital body tissues. This study aimed to investigate the protective effects of Sanyar prebiotic on the immunity and tissue changes of common carp (Cyprinus carpio) exposed to CuSO4 stress. Two hundred common carp fish with an average weight of 12.33 ± 0.93 g were stocked in four treatments (triplicates) for 60 days. The experimental treatments contained Sanyar commercial prebiotics in 100 g of food, which included P1 (1 ml prebiotic liquid), P2 (0.1 g prebiotic powder), P3 (0.5 ml liquid and 0.05 g powder), and treatment C (control treatment without any additives). At the end of the experimental period, the fish were exposed to acute toxicity of Cu (0.1 m/l) for 96 hours. Gill, kidney, and liver tissue samples were collected and evaluated after 96 hours. According to the results obtained, there were significant differences in specific growth rate (SGR) and final weight ( p &lt; 0.05). The lowest feed conversion ratio (FCR) was observed in the Sanyar treatments (1.56 ± 0.37), which had a significant difference from the control treatment (1.85 ± 0.35) ( p &lt; 0.05). The results showed that immunity indices such as lysozyme, cortisol, and ACH50 increased in the experimental treatments compared to the control treatment ( p &lt; 0.05). The highest and lowest lysozyme activities were observed in P2 (16.35 ± 0.57) and control treatments (13.15 ± 1.00), respectively ( p &lt; 0.05). Generally, no significant difference was observed between growth and nutrition indices in Sanyar treatments ( p &lt; 0.05). Symptoms of kidney, liver, and gill tissue damage were reported from mild (hyperemia and infiltration of inflammatory cells) to severe (hemorrhage and necrosis). The lowest severity of tissue damage was observed in the treatments fed with Sanyar food supplement. In general, the results of this study showed that the addition of Sanyar prebiotic to the diet of common carp improves the growth indicators and immune response and can also be beneficial in increasing fish resistance to copper toxicity.

Investigations into Increased Incidence of Severe Gizzard Erosions and Ulcerations in U.S. Commercial Broilers.

During a series of pathology surveys in four production complexes of a U.S. broiler integrator, the technical services veterinarians of an animal health company noted a high incidence of severe gizzard erosions and ulcerations (GEU), prompting further clinical investigation and a battery trial. No growth-promoting antibiotics or ionophore coccidiostats were used during the period of these surveys. All used tribasic copper chloride (TBCC) at ≤120 ppm added copper in broiler rations. Clostridium perfringens was isolated from 83% and 67% of gizzard lesions cultured in two complexes, and cecal C. perfringens most probable number determinations were higher in severely affected than in mildly affected or unaffected birds. Histopathology revealed both acellular koilin fusion defects characteristic of copper toxicity, as well as inflammatory cell infiltrates. Intralesional bacilli suggestive of C. perfringens were noted in 78% of affected flocks examined. Species E Aviadenovirus was isolated from one bird in one complex, and that bird had a single intranuclear inclusion body; no other flocks had Adenoviruses isolated or detected on PCR, nor any inclusion bodies. Other viruses detected were thought to be incidental. A pilot study using feed with supplemental copper from TBCC or copper sulfate and challenge with one of the isolated C. perfringens strains reproduced the lesions. A battery study was conducted with an unchallenged negative control group fed a diet with 16 ppm added copper, a group fed the control diet and orally challenged with 108 organisms of a field strain of C. perfringens at 21 and 22 days, and a group treated with the same diet containing 250 ppm added copper from TBCC and orally challenged with C. perfringens. Birds were necropsied at 23 and 28 days. All challenged groups developed lesions, with those receiving both TBCC and C. perfringens having significantly higher gross and histopathological lesion scores than the unchallenged negative controls. Lesions were qualitatively similar to those in the field and contained suspected C. perfringens bacilli. Because the levels of TBCC used in the commercial birds and in the battery trial generally have been considered safe, and because C. perfringens is usually regarded as a pathogen of the lower GI tract, the possible association of these two agents with GEU is a novel observation and warrants further investigation.

Co-Composting of Hop Bines and Wood-Based Biochar: Effects on Composting and Plant Growth in Copper-Contaminated Soils

Decades of intensive use of copper-based fungicides against downy mildew in hops has led to considerable accumulation of copper in topsoil, resulting in toxic effects on plants. Due to its high sorption capacity, the application of co-composted biochar compost might reduce copper toxicity, whereby a synergistic effect of the composting process is supposed to occur. Furthermore, biochar addition might improve the composting process itself. Therefore, hop bines were co-composted without as well as with 5 and 20 vol% biochar, respectively. During composting, the temperature and concentration of O2, CO2, H2S, CH4 and NH3 in the compost heaps were regularly recorded. The biochar-free compost as well as the two composts with the biochar addition were characterized with regard to their plant-growing properties and were mixed into soils artificially spiked with different amounts of copper as well as into copper-polluted hop garden and apple orchard soils. The respective soil without the compost addition was used as the control, and further treatments with biochar alone and in combination with biochar-free compost were included in a plant response test with Chinese cabbage. The biochar addition increased the temperature within the compost heaps by about 30 °C and extended the duration of the thermophilic phase by almost 30 days, resulting in a higher degree of hygienization. Furthermore, the application of co-composted biochar composts significantly improved plant biomass by up to 148% and reduced the copper concentration, especially of roots, by up to 35%. However, no significant differences in the biochar-free compost were found in the artificially copper-spiked soils, and the effect of co-composted biochar compost did not differ from the effect of biochar alone and in combination with biochar-free compost. Nevertheless, the co-composting of hop bines with biochar is recommended to benefit from the positive side effect of improved sanitization in addition to reducing copper toxicity.

Copper management strategies in obligate bacterial symbionts: balancing cost and benefit.

Bacteria employ diverse mechanisms to manage toxic copper in their environments, and these evolutionary strategies can be divided into two main categories: accumulation and rationalization of metabolic pathways. The strategies employed depend on the bacteria's lifestyle and environmental context, optimizing the metabolic cost-benefit ratio. Environmental and opportunistically pathogenic bacteria often possess an extensive range of copper regulation systems in order to respond to variations in copper concentrations and environmental conditions, investing in diversity and/or redundancy as a safeguard against uncertainty. In contrast, obligate symbiotic bacteria, such as Neisseria gonorrhoeae and Bordetella pertussis, tend to have specialized and more parsimonious copper regulation systems designed to function in the relatively stable host environment. These evolutionary strategies maintain copper homeostasis even in challenging conditions like encounters within phagocytic cells. These examples highlight the adaptability of bacterial copper management systems, tailored to their specific lifestyles and environmental requirements, in the context of an evolutionary the trade-off between benefits and energy costs.

Assessing the disparity: comparative toxicity of Copper in zebrafish larvae exposes alarming consequences of permissible concentrations in Brazil

ABSTRACT Copper (Cu) is a naturally occurring metal with essential micronutrient properties. However, this metal might also pose increased adverse environmental and health risks due to industrial and agricultural activities. In Brazil, the maximum allowable concentration of Cu in drinking water is 2 mg/L. Despite this standard, the impact of such concentrations on aquatic organisms remains unexplored. This study aimed to evaluate the toxicity of CuSO4 using larval zebrafish at environmentally relevant concentrations. Zebrafish (Danio rerio) larvae at 72 hr post-fertilization (hpf) were exposed to nominal CuSO4 concentrations ranging from 0.16 to 48 mg/L to determine the median lethal concentration (LC50), established at 8.4 mg/L. Subsequently, non-lethal concentrations of 0.16, 0.32, or 1.6 mg/L were selected for assessing CuSO4 -induced toxicity. Morphological parameters, including body length, yolk sac area, and swim bladder area, were adversely affected by CuSO4 exposure, particularly at 1.6 mg/L (3.31 mm ±0.1, 0.192 mm2 ±0.01, and 0.01 mm2 ±0.05, respectively). In contrast, the control group exhibited values of 3.62 mm ±0.09, 0.136 mm2 ±0.013, and 0.3 mm2 ±0.06, respectively. Behavioral assays demonstrated impairments in escape response and swimming capacity, accompanied by increased levels of reactive oxygen species (ROS) and lipid peroxidation. In addition, decreased levels of non-protein thiols and reduced cellular viability were noted. Data demonstrated that exposure to CuSO4 at similar concentrations as those permitted in Brazil for Cu adversely altered morphological, biochemical, and behavioral endpoints in zebrafish larvae. This study suggests that the permissible Cu concentrations in Brazil need to be reevaluated, given the potential enhanced adverse health risks of exposure to environmental metal contamination.

A first estimation of the role of penguin guano on copper cycling and organic speciation in Antarctic coastal waters

Cu is a vital micronutrient, but free Cu ions (Cu2+) in seawater, even at subnanomolar concentrations, can impede phytoplankton growth. Natural Cu complexation with organic ligands regulates Cu acquisition and, in most instances, reduces Cu2+ concentrations below toxic thresholds. Along the Antarctic coast, the sources and sinks of Cu and its associated ligands remain poorly defined. Despite the high productivity in the area, there are no studies on the role of trophic transfer in Cu cycling.This study explores penguin guano release of Cu and Cu ligands and its potential in neutralizing copper toxicity along the Antarctic coast. We collected guano in a Chinstrap penguin nesting location in the West coast of Deception Island and extracted its components into aqueous solution imitating natural processes. Copper concentration in guano was 0.4 mg (dry weight g)−1 constituting a potential toxic threat and showed biomagnification with respect to krill. Surface seawater samples collected from various locations varying in penguin activity, were analyzed to assess the potential influence of guano on the area. Visual examination and elevated levels of Al suggested that a substantial portion of guano was lithogenic. Consequently, only a modest 16 % of the total Cu present in guano could be extracted using mechanical methods. Notably, the concentrations of the extracted organic ligands were approximately 23 times higher than the concentrations of the extracted Cu. This significant presence of ligands effectively nullifies any potential toxicity that could have arisen from free Cu2+ ions. Guano ligands' conditional stability constants were lower than those in surface seawater suggesting phytoplankton exudation was the main ligand source in the area. Overall, guano acts as a key node for Cu cycling in coastal Antarctic waters but its deleterious potential is neutralized by ligands from krill digestion and the high background concentration of phytoplankton exudates.

Zinc’s Role in Mitigating Copper Toxicity for Plants and Microorganisms in Industrially Contaminated Soils: A Review

Zinc’s Role in Mitigating Copper Toxicity for Plants and Microorganisms in Industrially Contaminated Soils: A Review

Copper and nanocopper toxicity using integrated biomarker response in Pangasianodon hypophthalmus.

The current study focused on assessing the toxicological effects of copper (Cu) and copper nanoparticles (Cu-NPs) in acute condition on Pangasianodon hypophthalmus. The median lethal concentration (LC50 ) for Cu and Cu-NPs were determined as 8.04 and 3.85 mg L-1 , respectively. For the subsequent definitive test, varying concentrations were selected: 7.0, 7.5, 8.0, 8.5, and 9.0 mg L-1 for Cu, and 3.0, 3.3, 3.6, 3.9, and 4.2 mg L-1 for Cu-NPs. To encompass these concentration levels and assess their toxic effects, biomarkers associated with toxicological studies like oxidative stress, neurotransmission, and cellular metabolism were measured in the liver, kidney, and gill tissues. Notably, during the acute test, the activities of catalase, superoxide dismutase, glutathione-s-transferase, glutathione peroxidase, and lipid peroxide in the liver, gill, and kidney tissues were significantly increased due to exposure to Cu and Cu-NPs. Similarly, acetylcholinesterase activity in the brain was notably inhibited in the presence of Cu and Cu-NPs when compared to the control group. Cellular metabolic stress was greatly influenced by the exposure to Cu and Cu-NPs, evident from the considerable elevation of cortisol, HSP 70, and blood glucose levels in the treated groups. Furthermore, integrated biomarker response, genotoxicity, DNA damage in gill tissue, karyotyping in kidney tissue, and histopathology in gill and liver were investigated, revealing tissue damage attributed to exposure to Cu and Cu-NPs. In conclusion, this study determined that elevated concentrations of essential trace elements, namely Cu and Cu-NPs, induce toxicity and disrupt cellular metabolic activities in fish.

Copper – a scoping review for Nordic Nutrition Recommendations 2023

Copper functions as a structural component in many proteins involved in energy and iron metabolism, production of neurotransmitters, formation of connective tissue and endogenous antioxidant defence. Several biochemical indices have been suggested and used to assess copper status, but none of these has been found suitable for the detection of marginal copper deficiency or marginal copper toxicity. Copper imbalances have been linked to the pathogenesis of several chronic inflammatory diseases. During the last decade, a number of meta-analyses and systematic reviews have been published shedding light on the association between copper imbalances and some of these pathologies. Most of these meta-analyses are based on case–control studies. All show that blood copper concentrations are higher in cases than in controls, but there is inconclusive evidence to change the recommendations.

Amino-functionalized SiO2 microbeads optimize photosynthetic performance, gene expression, ROS production and antioxidant status in chromium and copper-exposed Zea mays

The objective of the current study was to assess the potential of the amino-functionalized SiO2 microbeads (S) in improving the tolerance of maize to chromium and/or copper toxicity. For this purpose, Zea mays L. cv. DKC5685 was grown by exposure at different S concentrations (100–500 mg L-1) alone and with 200 µM chromium (Cr stress) and 100 µM copper (Cu stress) for 7 days. The photosynthesis-related parameters (Fv/Fm, Fv/Fo), relative growth rate (RGR), and relative water content (RWC) levels were suppressed under Cr and/or Cu stresses. In addition, stress altered antioxidant activities and gas exchange parameters. S applications abolished the negative impacts of stress on the physiological state of the photosynthetic system, potential photochemical efficiency and chlorophyll fluorescence. S increased the performance index by reversing the detrimental effects on the electron flow rate through the PSII electron transport flux and electron transfer from the decreased plastoquinone pool to the PSI reaction center. Following exposure to S, the effects of stress on photosystem I-associated reaction center proteins were rearranged by induced expression levels of PsaA and PsaB genes. S treatments had potent ROS scavengers in maize leaves. In the Cr+S groups, the AsA-GSH cycle was regulated by increasing the activities of all the responsible enzymes mentioned above, such as SOD, CAT, APX and GR, and the accumulation of H2O2 and TBARS effectively removed. CAT and POX activities in Cu+S groups were not effective in these adjustments. In Cr+Cu+S applications, although H2O2 and TBARS contents were reduced as evidenced by ROS visualization using fluorescence of dye, AsA regeneration could not be achieved, and low tAsA/DHA levels were detected. Our results show that amino-functionalized SiO2 microbeads have significant promise to offer resistance to maize by minimizing oxidative damage brought on by heavy metal uptake and preserving the metabolic processes involved in photosynthesis.

Cadmium and copper-induced metabolic and proteomic changes in the root tip during early maize growth.

In this study, the metabolic adjustments performed by maize (Zea mays L.) seminal roots exposed to 25µM Cd2+ or 25µM Cu2+ at pre-emergence are compared, focusing on the proteomic changes after metal exposure. Root width was increased, and root length was decreased after 72h of metal treatment. Both metals induced H2O2 accumulation and lipid peroxidation in the root tip. These changes were accompanied by increases in lipoxygenase activity and 4-hydroxy-2-nonenal content. NMR spectroscopy revealed that the abundance of 38 water-soluble metabolites was significantly modified by Cd and Cu exposure; this set of metabolites comprised carboxylic acids, amino acids, carbohydrates, and unidentified phenolic compounds. Linoleic acid content significantly decreased in Cu-treated samples. The total amount of proteins detected in maize root apexes was 2,171. Gene ontology enrichment analysis of the differentially accumulated proteins was performed to detect pathways probably affected by metal additions. Both metals altered redox homeostasis, up-regulated oxylipins biosynthetic process, and shifted metabolism towards the oxidative pentose-phosphate in the root apexes. However, the methionine salvage pathway appears as a key metabolic module only under Cd stress. The integrative analysis carried out in this study suggests that most molecular features behind the reprogramming of maize root tips to cope with cadmium and copper toxicity are common, but some are not.

Waste biomass derived highly-porous carbon material for toxic metal removal: Optimisation, mechanisms and environmental implications

Toxic elements, lead, and copper are often found in wastewater discharged from industries such as mining. The discharge of untreated effluent poses severe environmental challenges and sorption methods using agricultural waste materials are proposed as an efficient and cost-effective solution. For this research, activated sunflower material (ASM) was prepared from abundantly available agricultural sunflower waste residues and utilised to remove Pb2+ and Cu2+ ions from an aqueous medium. To begin, we examine variables that may have an impact on the adsorption process, such as pH, contact time, adsorbent dose, and initial concentration using Box-Behnken Design (BBD) to find optimal conditions. Maximum removal efficiency was found at a pH of 5, contact time of 180 min, and initial concentration of 50 mg/L for Pb2+ and 150 mg/L for Cu2+. Additionally, adsorbent dose differed by element, for Cu2+ it was 200 mg, whilst for Pb2+ it was 124 mg. Features of activated carbon such as morphology, elemental composition, textural properties, and surface functionalities were characterised using SEM-EDS, BET, FTIR, and XPS. The adsorption equilibrium data were analysed by Langmuir, Freundlich, and Dubinin-Radushkevich isotherm models. It was found that the obtained results for Pb2+ adsorption were better described with the Freundlich isotherm model. Maximum adsorption capacities for Pb2+ and Cu2+ were 91.8 mg/g and 20.5 mg/g, respectively. Furthermore, kinetic studies confirmed that the adsorption process followed a pseudo-first-order kinetic model for Pb2+, but for Cu2+ all applied kinetic models fitted experimental data with the same values of the correlation coefficient (R2 = 0.99). After comprehensive analysis using the methods mentioned above, ASM was tested for the removal of Cu2+ from mining wastewater sample, and the obtained removal efficiency was 98.6% ± 2.0%. The results of desorption experiments conducted, confirm that ASM has good potential to be reused for the purpose of removing Cu2+ from wastewater.

Histological features of liver disease development in the Atp7b−/− mouse: a model of Wilson’s disease

AimsWilson’s disease (WD) is caused by mutations in the ATP7B gene, resulting in copper accumulation and toxicity in liver and brain tissues. Due to the initial asymptomatic liver involvement, the...