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1.
Water Sci Technol ; 81(7): 1471-1478, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32616699

RESUMEN

SiO2 gel was formed on the grain surface of silica sand by hydrolysis and condensation of tetraethyl orthosilicate in water with the addition of 1-butylamine. The resultant product was a composite consisting of sand grains with mesoporous silica coating containing alkylamine inside. This composite exhibited basicity in the wastewater from copper electroplating due to its release of amine. As a result, the strongly acidic wastewater was neutralized and the co-precipitation of complex metal ions occurred. It was shown that up to 12 major metal ions in the wastewater could be simultaneously removed under static condition at room temperature by using the sand composite. The Fe and Cu in the wastewater could be removed completely, while the concentrations of Al, Cd, Ti, V, and Zn in the wastewater were reduced by two to three orders of magnitude. After the removal of multiple metal ions from the electroplating wastewater, the used sand was further applied as a raw material for making a silicate glass. The glass was chemically stable and thus the heavy metal ions from the wastewater were immobilized.


Asunto(s)
Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , Cobre , Galvanoplastia , Iones , Arena , Dióxido de Silicio , Aguas Residuales
2.
In Vivo ; 34(3 Suppl): 1567-1588, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32503814

RESUMEN

BACKGROUND: On March 11, 2020, the World Health Organization (WHO) declared the outbreak of coronavirus disease (COVID-19) a pandemic. Since then, thousands of people have suffered and died, making the need for a treatment of severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV-2) more crucial than ever. MATERIALS AND METHODS: The authors carried out a search in PubMed, ClinicalTrials.gov and New England Journal of Medicine (NEJM) for COVID-19 to provide information on the most promising treatments against SARS-CoV-2. RESULTS: Possible COVID-19 agents with promising efficacy and favorable safety profile were identified. The results support the combination of copper, N-acetylcysteine (NAC), colchicine and nitric oxide (NO) with candidate antiviral agents, remdesivir or EIDD-2801, as a treatment for patients positive for SARS-CoV-2. CONCLUSION: The authors propose to study the effects of the combination of copper, NAC, colchicine, NO and currently used experimental antiviral agents, remdesivir or EIDD-2801, as a potential treatment scheme for SARS-COV-2.


Asunto(s)
Acetilcisteína/uso terapéutico , Adenosina Monofosfato/análogos & derivados , Alanina/análogos & derivados , Antivirales/uso terapéutico , Colchicina/uso terapéutico , Cobre/uso terapéutico , Infecciones por Coronavirus/tratamiento farmacológico , Óxido Nítrico/uso terapéutico , Neumonía Viral/tratamiento farmacológico , Ribonucleósidos/uso terapéutico , Acetilcisteína/administración & dosificación , Acetilcisteína/farmacología , Adenosina Monofosfato/administración & dosificación , Adenosina Monofosfato/farmacología , Adenosina Monofosfato/uso terapéutico , Adyuvantes Inmunológicos/administración & dosificación , Adyuvantes Inmunológicos/uso terapéutico , Alanina/administración & dosificación , Alanina/farmacología , Alanina/uso terapéutico , Antiinflamatorios/administración & dosificación , Antiinflamatorios/uso terapéutico , Antivirales/administración & dosificación , Antivirales/farmacología , Autofagia/efectos de los fármacos , Betacoronavirus/efectos de los fármacos , Betacoronavirus/fisiología , Colchicina/administración & dosificación , Colchicina/farmacología , Cobre/administración & dosificación , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/fisiopatología , Sinergismo Farmacológico , Quimioterapia Combinada , Humanos , Inflamación , Óxido Nítrico/administración & dosificación , Óxido Nítrico/farmacología , Pandemias , Neumonía Viral/inmunología , Neumonía Viral/fisiopatología , Profármacos/administración & dosificación , Profármacos/uso terapéutico , Ribonucleósidos/administración & dosificación , Ribonucleósidos/farmacología , Internalización del Virus/efectos de los fármacos , Replicación Viral/efectos de los fármacos
3.
Water Sci Technol ; 81(5): 1063-1070, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32541122

RESUMEN

A cross-linked chitosan-PVA spherical hydrogel (CSH) was synthesized and its structure was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The physical and chemical properties of CSH, such as acid resistance and swelling, were determined. Finally, Cu(II) ion removal by the CSH was investigated, and the effects of experimental parameters, including pH, adsorption time, and regeneration performance were examined. Results revealed that CSH has outstanding stability in strong acid solution, thus extending the useful pH range as an adsorbent material. The maximum capacity of CSH for Cu(II) was obtained to be 62.1 mg/g at 25 °C for 24 h. The adsorption process was best described by a pseudo-second-order kinetic model, while isotherm modeling revealed that the Langmuir equation better described the adsorption of Cu(II) on CSH. Moreover, the loaded CSH can be easily regenerated by the HCl-washing method and reused repeatedly for Cu(II) adsorption for up to five cycles.


Asunto(s)
Quitosano , Contaminantes Químicos del Agua , Adsorción , Cobre , Hidrogeles , Concentración de Iones de Hidrógeno , Iones , Cinética , Espectroscopía Infrarroja por Transformada de Fourier
4.
J Environ Manage ; 268: 110733, 2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-32510453

RESUMEN

Mineral exploration of copper (Cu) in the Amazon has significantly impacted the environment, leading to contamination of large areas that require remediation. Tropical tree species that can immobilize metals and restore plant cover should be selected for phytoremediation programs. The phytoremediation behavior of Khaya ivorensis and Cedrela fissilis was studied in Cu contaminated soil (60, 200, 400, and 600 mg kg-1). K. ivorensis absorbed extremely high amounts of Cu in the roots (329 mg kg-1) and excessive amounts in the shoot (52 mg kg-1), while maintaining similar growth to control plants. C. fissilis seedlings presented a higher Dickson quality index. Bioaccumulation (BCF) and translocation (TF) factors were low in both species, indicating that even with the high amounts of copper absorbed, these contents were lower than the soil concentration (BCF < 1) and that most of Cu was compartmentalized in the roots (TF < 1). The tolerance index of K. ivorensis (>1) and C. fissilis (~1) indicate their ability to grow in Cu contaminated soil. These results suggest that these species could potentially be used as phytoremediators.


Asunto(s)
Cedrela , Metales Pesados , Contaminantes del Suelo , Biodegradación Ambiental , Cobre , Suelo
5.
J Adhes Dent ; 22(3): 265-274, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32435767

RESUMEN

PURPOSE: To investigate whether dental adhesives modified with polyacrylic acid copper iodide particles could inhibit esterase activity in vitro and the copper release rate from resin matrices, as well as the correlation between the two variables. MATERIALS AND METHODS: Different concentrations of copper iodide (0.1, 0.5 and 1.0 mg/ml) were incorporated into three commercially available adhesives representative of each type. Disk specimens (n = 3) were fabricated and incubated in cholesterol esterase and pseudo-cholinesterase solutions for 16 days (37°C, pH 7.0). The enzymatic activity and rate of copper release from resin matrices were evaluated at different 4, 8, 12, and 16 days with a UV/visible-light spectrophotometer. RESULTS: Increased copper release and reduced enzymatic activity were observed with higher concentrations of copper iodide (p < 0.001). Greater copper release with reduced enzymatic activity was also demonstrated at the earlier time periods with this relationship reversing over time (p < 0.001). A moderate negative correlation between the variables was evident (-0.441; p = 0.01). CONCLUSIONS: Adhesives containing copper iodide can inhibit esterase activity in a dose- and time-dependent manner. The correlation between the variables suggests that enzymatic activity may depend on the availability of copper.


Asunto(s)
Cementos Dentales , Yoduros , Cobre , Esterasas , Ensayo de Materiales
6.
Waste Manag ; 108: 172-182, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32360998

RESUMEN

The coordinated treatment for two kinds of waste is an effective way to save energy and improve the recovery efficiency of resource. In worldwide, more than half of palladium is used to produce catalysts in automobile. However, with the increasing consumption of palladium, the scarcity of palladium resource is becoming prominent. This paper proposed an integrated process based on capture of copper scrap and electrodeposition process to recycle palladium in spent catalysis from automobile. The technological process mainly consisted of two procedures: capture of copper scrap with the purposes of enriching palladium and electrodeposition process with the purposes of separating and purifying palladium. Several highlights were summarized as follows: (i) a capture mechanism of palladium by copper scrap was studied by the calculation of surface thermodynamics and first principles. (ii) Optimum designs, parameter and product analysis were developed to guide industrial recycling. The appropriate parameters for capture of copper scrap are the melting temperature reached 1400 °C, adding 20% dosage of copper scrap and 2 of mass ratio of SiO2/Al2O3 and for the electrodeposition process, nearly 100% of palladium was deposited on the cathode under 0.1 M concentration of HNO3, -0.042 V of electrodeposition potential and 25 °C reaction temperature with 9 h. (iii) This process overcame the shortages of traditional process and showed its efficiency and environmental performance. This study is significant for high-efficient, low-cost and environment-friendly recycling of valuable resource in spent catalysis from automobile.


Asunto(s)
Cobre , Paladio , Automóviles , Catálisis , Galvanoplastia , Reciclaje , Dióxido de Silicio
7.
Science ; 368(6491): 584-585, 2020 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-32381707
8.
Sci Total Environ ; 730: 139119, 2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-32402973

RESUMEN

Biochars are widely used in the remediation of soil heavy metals, but there has been no clear understanding to the effects of novel co-pyrolysis biochars derived from biomass and orthophosphate on soil heavy metals. In this study, co-pyrolysis biochars derived from rape straw and orthophosphate (Ca (H2PO4)2·H2O/KH2PO4) were prepared and used to explore their effects on the speciations and ecological risks of Pb, Cd, and Cu in contaminated agricultural soil. The results showed that the addition of these co-pyrolysis biochars significantly decreased TCLP extracted concentrations (decreased by 5.9-81.7%) and ecological risks of heavy metals (Pb, Cd, and Cu) by transforming the metals from available speciation to stable speciation in soils. Co-pyrolysis biochar derived from rape straw and KH2PO4 showed the highest immobilization capacities, and the immobilization capacities of biochars for three metals were in the order of Pb > Cu > Cd. Co-pyrolysis biochars could precipitate and complex with heavy metals directly by the phosphate and -OH on their surface, and also could promote immobilization of heavy metals indirectly by increasing soil pH value and available P content. During incubation, the content of carboxyl groups on biochars increased significantly, which was beneficial to the further complexation of heavy metals. In summary, the application of co-pyrolysis biochar derived from rape straw and orthophosphate (especially for KH2PO4) could effectively reduce ecological risks of Pb, Cd, and Cu in contaminated soil.


Asunto(s)
Contaminantes del Suelo/análisis , Cadmio , Carbón Orgánico , Cobre , Plomo , Metales Pesados , Fosfatos , Pirólisis , Suelo
9.
Sci Total Environ ; 730: 138597, 2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-32428803

RESUMEN

Contamination by estrogens and heavy metals can cause great environment concern and necessitate efficient approaches for their removals. In this study, the combined effects of 17ß-estradiol (E2) and Cu(II) on microalgae growth and biochemical characteristics were investigated. Results showed that 1 mg/L Cu(II) promoted the growth of Scenedesmus dimorphus, while 2 mg/L Cu(II) exhibited growth inhibition, compared with the same concentration of E2. Biochemical characteristics including enzyme activities as well as the contents of chlorophyll, protein and carbohydrate were significantly affected by the coexistence of E2 and Cu(II) after 12 d of cultivation. S. dimorphus exhibited high E2 and Cu(II) removal efficiencies (89.9% of E2 and 76.6% Cu(II) under the coexistence of 0.5 mg/L E2 and 1 mg/L Cu(II), respectively). Lower concentration of Cu(II) might serve as a bridge during E2 removal by S. dimorphus while competitive adsorption of Cu(II) and E2 occurred under the condition of excessive Cu(II). Results could confirm that S. dimorphus was a potential bioresource for the effective removal of E2 and Cu(II).


Asunto(s)
Microalgas , Scenedesmus , Cobre , Contaminantes Ambientales , Estradiol , Agua Dulce
10.
Int J Nanomedicine ; 15: 2541-2553, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32368039

RESUMEN

Background: In the emerging field of nanotechnology, copper oxide (CuO) nanomaterials are considered to be one of the most important transition metal oxides owing to its fascinating properties. Its synthesis from green chemistry principles is gaining importance as next-generation antibiotics due to its simplicity, eco-friendliness, and cost-effectiveness. In the present study, CuO nanorods (CuO NRs) were synthesized from the aqueous fruit extract of Momordica charantia and characterized using different analytical techniques. Further, the biomedical therapeutic potential was evaluated against multi-drug resistant microbial strains. Materials and Methods: To synthesize CuO NRs, 0.1M of CuSO4.5H2O solution was added to aqueous extract of Momordica charantia in a 1:3 (v/v) ratio (pH=11) and heated at 50°C followed by washing and drying. The synthesized CuO NRs were subjected to characterization using different analytical techniques such as UV visible spectroscopy, zeta sizer equipped with zeta potential, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM). Further, the application as a biomedical therapeutic potential was evaluated in vitro using well diffusion method against eleven multidrug-resistant clinical bacterial strains, a fungus- Trichophyton rubrum and in ovo against the R2B virus using haemagglutination (HA) test. Results: Characterization was preliminarily done by the spectral study that confirms the absorbance band at 245nm. FTIR analysis at 628 cm-1 peak identified copper oxide vibration. SEM analysis revealed agglomerated particle clusters. However, with TEM clear nanorods of average diameter of 61.48 ± 2 nm were observed. EDAX confirmed CuO formation while XRD showed a typical monoclinic structure with 6 nm crystallite size. Biological screening of CuO NRs showed significant results against both in vitro and in ovo methods. Significant inhibitory activity (p<0.0001) was noted against most of the resistant human pathogenic strains including both Gram-positive and Gram-negative bacteria. The highest efficacy was observed against Bacillus cereus with a 31.66 mm zone of inhibition. Besides, the therapeutic potential of CuO NRs against Corynebacterium xerosis, Streptococcus viridians and R2B strain of Newcastle disease is reported for the first time. Conclusion: Based on the present results, it could be expected that green synthesized CuO NRs would find potential applications in the field of nanomedicine.


Asunto(s)
Antibacterianos/farmacología , Cobre/farmacología , Tecnología Química Verde , Momordica charantia/química , Nanoestructuras/química , Animales , Antifúngicos/farmacología , Bacterias/efectos de los fármacos , Pollos , Hongos/efectos de los fármacos , Pruebas de Hemaglutinación , Humanos , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana , Nanoestructuras/ultraestructura , Nanotubos/química , Nanotubos/ultraestructura , Tamaño de la Partícula , Espectrometría por Rayos X , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática , Difracción de Rayos X
11.
Int J Nanomedicine ; 15: 2583-2603, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32368042

RESUMEN

Introduction: Over the past several years, nano-based therapeutics were an effective cancer drug candidate in order to overcome the persistence of deadliest diseases and prevalence of multiple drug resistance (MDR). Methods: The main objective of our program was to design organosilane-modified Fe3O4/SiO2/APTS(~NH2) core magnetic nanocomposites with functionalized copper-Schiff base complex through the use of (3-aminopropyl)triethoxysilane linker as chemotherapeutics to cancer cells. The nanoparticles were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), field emission scanning electron microscopy (FE-SEM), TEM, and vibrating sample magnetometer (VSM) techniques. All analyses corroborated the successful synthesis of the nanoparticles. In the second step, all compounds of magnetic nanoparticles were validated as antitumor drugs through the conventional MTT assay against K562 (myelogenous leukemia cancer) and apoptosis study by Annexin V/PI and AO/EB. The molecular dynamic simulations of nanoparticles were further carried out; afterwards, the optimization was performed using MM+, semi-empirical (AM1) and Ab Initio (STO-3G), ForciteGemo Opt, Forcite Dynamics, Forcite Energy and CASTEP in Materials studio 2017. Results: The results showed that the anti-cancer activity was barely reduced after modifying the surface of the Fe3O4/SiO2/APTS nanoparticles with 2-hydroxy-3-methoxybenzaldehyde as Schiff base and then Cu(II) complex. The apoptosis study by Annexin V/PI and AO/EB stained cell nuclei was performed that apoptosis percentage of the nanoparticles increased upon increasing the thickness of Fe3O4 shell on the magnetite core. The docking studies of the synthesized compounds were conducted towards the DNA and Topoisomerase II via AutoDock 1.5.6 (The Scripps Research Institute, La Jolla, CA, USA). Conclusion: Results of biology activities and computational modeling demonstrate that nanoparticles were targeted drug delivery system in cancer treatment.


Asunto(s)
Cobre/química , Compuestos Férricos/síntesis química , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Propilaminas/síntesis química , Bases de Schiff/síntesis química , Silanos/síntesis química , Dióxido de Silicio/síntesis química , Apoptosis , Núcleo Celular/metabolismo , ADN/química , ADN-Topoisomerasas de Tipo II/química , Compuestos Férricos/química , Humanos , Células K562 , Magnetismo , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/ultraestructura , Propilaminas/química , Bases de Schiff/química , Silanos/química , Dióxido de Silicio/química , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
12.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 32(3): 290-293, 2020 Apr 26.
Artículo en Chino | MEDLINE | ID: mdl-32468792

RESUMEN

OBJECTIVE: To evaluate the effects of Cu2+ and Cd2+ at different concentrations on superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) activity in Oncomelania hupensis. METHODS: Cu2+- and Cd2+-containing solutions were prepared at 7 concentrations, and O. hupensis snails were exposed to the solutions for 24 h, of 15 snails in each concentration. Then, the snail body was collected following removal of the snail shell and homogenated, and the SOD, CAT and POS activities were detected in the supernatants. RESULTS: With the increase of the Cu2+ concentration, the SOD activity appeared a rise followed by a reduction in O. hupensis snails, and the CTA activity appeared a decline-rise-decline tendency, while the POD activity showed a tendency towards rise followed by decline. With the increase of the Cd2+ concentration, the SOD activity appeared a rise followed by a reduction in O. hupensis snails, and the CTA activity appeared a decline- rise- decline tendency, while the POD activity showed a decline-rise-decline tendency. CONCLUSIONS: Exposure to Cu2+ and Cd2+ at high concentrations results in a decline in the activity of SOD, CAT and POD in O. hupensis at the same time.


Asunto(s)
Cadmio , Cobre , Oxidorreductasas , Caracoles , Animales , Cadmio/toxicidad , Catalasa/metabolismo , Cobre/toxicidad , Activación Enzimática/efectos de los fármacos , Iones/toxicidad , Oxidorreductasas/metabolismo , Peroxidasa/metabolismo , Caracoles/efectos de los fármacos , Caracoles/enzimología , Superóxido Dismutasa/metabolismo
13.
Environ Pollut ; 260: 113925, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32369894

RESUMEN

Copper is known to interfere with fish olfaction. Although the chemosensory detection and olfactory toxicity of copper ions (Cu2+) has been heavily studied in fish, the olfactory-driven detection of copper nanoparticles (CuNPs)-a rapidly emerging contaminant to aquatic systems-remains largely unknown. This study aimed to investigate the olfactory response of rainbow trout to equitoxic concentrations of CuNPs or Cu2+ using electro-olfactography (EOG, a neurophysiological technique) and olfactory-mediated behavioural assay. In the first experiment, the concentration of contaminants known to impair olfaction by 20% over 24 h (EOG-based 24-h IC20s of 220 and 3.5 µg/L for CuNPs and Cu2+, respectively) were tested as olfactory stimuli using both neurophysiological and behavioural assays. In the second experiment, to determine whether the presence of CuNPs or Cu2+ can affect the ability of fish to perceive a social cue (taurocholic acid (TCA)), fish were acutely exposed to one form of Cu-contaminants (approximately 15 min). Following exposure, olfactory sensitivity was measured by EOG and olfactory-mediated behaviour within a choice maze was recorded in the presence of TCA. Results of neurophysiological and behavioural experiments demonstrate that rainbow trout can detect and avoid the IC20 of CuNPs. The IC20 of Cu2+ was below the olfactory detection threshold of rainbow trout, as such, fish did not avoid Cu2+. The high sensitivity of behavioural endpoints revealed a lack of aversion response to TCA in CuNP-exposed fish, despite this change not being present utilizing EOG. The reduced response to TCA during the brief exposure to CuNPs may be a result of either olfactory fatigue or blockage of olfactory sensory neurons (OSNs) by CuNPs. The observed behavioural interference caused by CuNP exposure may indicate that CuNPs have the ability to interfere with other behaviours potentially affecting fitness and survival. Our findings also revealed the differential response of OSNs to CuNPs and Cu2+.


Asunto(s)
Cobre/toxicidad , Nanopartículas/toxicidad , Oncorhynchus mykiss , Trucha/fisiología , Contaminantes Químicos del Agua/toxicidad , Animales , Iones
14.
Environ Pollut ; 260: 114051, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32369896

RESUMEN

Soil contamination by toxic heavy metals such as copper is a serious problem. In this study, the extracellular polymeric substance (EPS) extracted from Rahnella sp. LRP3 was found with the potential of immobilizing Cu-polluted in soil. The EPS could bond to Cu (II) through functional groups (polysaccharides, amide, proteins, and carboxyl groups), which further developed into the porous sphere with a diameter of 20 µm. Besides, EPS could induce the formation of Cu5(PO4)2(OH)4 crystal by the biomineralization process. Finally, the EPS in the culture solution reduced 89.4 mg/kg of DTPA-Cu content by 78.99% in soil for 10 d under the condition of 25 °C via biomineralization. The results demonstrated that EPS produced by Rahnella sp. LRP3 will be a promising factor in the remediation of Cu contaminated soil.


Asunto(s)
Biomineralización , Cobre/química , Matriz Extracelular de Sustancias Poliméricas , Rahnella/fisiología , Suelo/química , Rahnella/efectos de los fármacos
15.
Chemosphere ; 251: 126309, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32443244

RESUMEN

Conventional techniques used for reduction of Cr(VI) in wastewater product great amounts of metal sludge due to the use of reducing chemicals. Since in electrochemical process, the reducing agent is the electron, so the main advantage of this method is its adaptability to the environment. The aim of the current study is to reduce Cr(VI) from electroplating wastewater by the electrochemical method and to adsorb Cr(III) by cellulose sulfate adsorbent. Furthermore, to enhance the reduction efficiency of Cr(VI), the cathode was modified with Pd nanoparticles. In the present study, recovery in the electrochemical column was conducted continuously and semi-continuously. In addition, the effect of pH, amperage, flow rate, and initial concentration of Cr(VI) was investigated. To remove Cr(III) from the wastewater, the cellulose sulfate adsorbent was provided from modification of cotton health wastes. The highest recovery rate (99.63%) was witnessed at pH = 1.5, 1 A amperage, flow rate of 4.24 mL min-1, and initial concentration of 50 mg L-1. The sewage was removed from the system after several consecutive cycles and during 20-55 min reached recovery efficiency of 99.99%. Based on the results, pH had the highest effect on the process. The optimum removal percentage was 85.74% occurred at a pH of 5.6, chromium concentration of 150 mg L-1, and adsorbent concentration of 400 mg L-1. The removal rate of the pollutant was 97.32%, done by cellulose sulfate adsorbent.


Asunto(s)
Cromo/análisis , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Adsorción , Celulosa/análogos & derivados , Cromo/química , Cobre , Electrodos , Galvanoplastia , Concentración de Iones de Hidrógeno , Nanopartículas del Metal , Paladio , Aguas del Alcantarillado , Contaminantes Químicos del Agua/química
16.
Sci Total Environ ; 734: 139434, 2020 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-32454337

RESUMEN

The long-term use of Cu-based fungicides at doses of several kilograms per hectare stimulated a wide debate about the human health and environmental risks of the progressive accumulation of Cu in agricultural soils. Here, the health risks due to copper accumulation in agricultural soils were evaluated with a survey in intensive agricultural land of the Campania region (Italy), aiming to evaluate Cu accumulation in food crops. The health risk due to dietary exposure was estimated by using the Hazard Quotient (HQ), calculated as the ratio between the average daily dose and the reference dose of copper, suggesting that when HQ > 1 there is a potential risk for consumers. According to a survey of soils with a Cu content up to 217 mg kg-1, no foodstuffs showed dietary risks. Nevertheless, the contribution of Cu contained in these foodstuffs to the overall intake of Cu by consumers could increase health risks since such risks must be evaluated on the basis of the whole standard diet by quantifying the Cu content not only in vegetables and fruits but also in other sources, such as cereals, not cultivated in the study area and thus not considered in this paper. The environmental risks due to copper accumulation in agricultural soils were then evaluated with a field experiment in a soil characterized by a very high Cu concentration (up to 1700 mg kg-1), aiming to study the impacts of Cu on native soil microorganisms. The study of the microbiota highlighted that the presence of Cu in soil did not reduce the total richness and diversity of microorganisms, which were not related to increasing concentrations of Cu in the soil. Nevertheless, Cu contamination was found to exert significant selection pressure on the soil microbiota, as shown by beta diversity and correlation analysis between taxa and Cu content.


Asunto(s)
Suelo , Cobre , Cadena Alimentaria , Italia , Medición de Riesgo , Microbiología del Suelo , Contaminantes del Suelo
17.
Chemosphere ; 251: 126424, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32443239

RESUMEN

Phytoremediation via phyto-extraction is well recognized and sustainable principle for the economical removal of heavy metals from contaminated water and soil. The twofold objective of the present research work was to investigate the remediation potential of fenugreek for Cu under the influence of ascorbic acid (AA). The effect of copper-ascorbic acid chelation on the growth regulation of fenugreek (Trigonella foenum-graceum L.) and its potential to accumulate Cu was investigated in hydroponic medium to optimize concentration with complete randomized design (CRD). Juvenile fenugreek plants were treated with different treatments of AA (5 mM) and Cu (100, 250 and 500 µM). The different morpho-physiological parameters of fenugreek plant such as growth, biomass and chlorophylls were significantly reduced under Cu stress. However, the activities of antioxidant enzymes, electrolyte leakage and reactive oxygen species enhanced with increasing concentration of applied Cu. Results indicated significant increase in plant growth, biomass, physiology and antioxidant enzymes and decrease in reactive oxygen species and electrolyte production in AA mediated fenugreek plants compared to controls and Cu only treated plants. However, it was also found that AA enhanced Cu concentration maximum up to 42% in leaf, 18% in stem and 45% in roots as compared to Cu treated only plants. Moreover, application of AA signified the research results revealing to act as growth regulator and chelator under Cu stress.


Asunto(s)
Biodegradación Ambiental , Cobre/metabolismo , Contaminantes del Suelo/metabolismo , Trigonella/metabolismo , Antioxidantes/metabolismo , Ácido Ascórbico/farmacología , Biomasa , Clorofila , Cobre/análisis , Metales Pesados/metabolismo , Hojas de la Planta/química , Raíces de Plantas/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Suelo , Contaminantes del Suelo/análisis
18.
Science ; 368(6491): 620-625, 2020 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-32381719

RESUMEN

Loss-of-function mutations in the copper (Cu) transporter ATP7A cause Menkes disease. Menkes is an infantile, fatal, hereditary copper-deficiency disorder that is characterized by progressive neurological injury culminating in death, typically by 3 years of age. Severe copper deficiency leads to multiple pathologies, including impaired energy generation caused by cytochrome c oxidase dysfunction in the mitochondria. Here we report that the small molecule elesclomol escorted copper to the mitochondria and increased cytochrome c oxidase levels in the brain. Through this mechanism, elesclomol prevented detrimental neurodegenerative changes and improved the survival of the mottled-brindled mouse-a murine model of severe Menkes disease. Thus, elesclomol holds promise for the treatment of Menkes and associated disorders of hereditary copper deficiency.


Asunto(s)
Cobre/metabolismo , Hidrazinas/uso terapéutico , Síndrome del Pelo Ensortijado/tratamiento farmacológico , Animales , Transporte Biológico/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/patología , Línea Celular , Transportador de Cobre 1/genética , Modelos Animales de Enfermedad , Complejo IV de Transporte de Electrones/metabolismo , Hidrazinas/farmacología , Masculino , Síndrome del Pelo Ensortijado/metabolismo , Síndrome del Pelo Ensortijado/patología , Ratones , Ratones Noqueados , Mitocondrias/metabolismo , Enfermedades Neurodegenerativas/prevención & control , Ratas
19.
Sheng Wu Gong Cheng Xue Bao ; 36(3): 471-480, 2020 Mar 25.
Artículo en Chino | MEDLINE | ID: mdl-32237541

RESUMEN

With the acceleration of industrialization and agriculture, soil heavy metal pollution has become increasingly serious. Copper, though an essential trace element for the growth and development of living organisms, is one of the main heavy metal pollutants. Excess copper in soil is toxic to plants and threatens human health via food chain. Bioremediation has received extensive attention as a novel technology for heavy-metal-contaminated soils. Here, we review the development of bioremediation technologies, including phytoremediation, microbial remediation, plant-microbe combined remediation, and animal remediation, for copper-contaminated soils, in order to provide a theoretical basis for the effective management of heavy-metal-contaminated soils and the sustainable development of agriculture.


Asunto(s)
Biodegradación Ambiental , Cobre , Contaminantes del Suelo , Cobre/metabolismo , Suelo , Contaminantes del Suelo/metabolismo
20.
Bioresour Technol ; 307: 123264, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32244076

RESUMEN

Nanoparticles and antibiotics, the two most frequently detected emerging pollutants from different wastewater sources, are eventually discharged into wastewater treatment plants. In this study, the widely used materials CuNPs and oxytetracycline (OTC) were selected as target pollutants to investigate their joint effects on anaerobic ammonium oxidation (anammox). The results indicated that the environmental concentration slightly inhibited the performance of the reactors, while the performance rapidly deteriorated within a week under high-level combined shocks (5.0 mg L-1 CuNPs and 2.0 mg L-1 OTC). After the second shock (2.5 mg L-1 CuNPs and 2.0 mg L-1 OTC), the resistance of anammox bacteria was enhanced, with an elevated relative abundance of Candidatus Kuenenia and absolute abundance of hzsA, nirS, and hdh. Moreover, the extracellular polymeric substance (EPS) content and specific anammox activity (SAA) showed corresponding changes. Improved sludge resistance was observed with increasing CuNP and OTC doses, which accelerated the recovery of performance.


Asunto(s)
Nanopartículas , Oxitetraciclina , Reactores Biológicos , Cobre , Matriz Extracelular de Sustancias Poliméricas , Nitrógeno , Oxidación-Reducción , Aguas del Alcantarillado
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