Doses Of Cu Research Articles

Impact of Cu(II)-doping on the vulnerability of Escherichia coli ATCC 10536 revealed by Atomic Force Microscopy

E. coli strain is a gram-negative bacterium known to induce both extra-intestinal infections and intestinal infections. For survival of microbes, metal intake and accessibility should be according to their physiological requirements. Peculiarly, copper homeostasis is critical for E. coli survival and growth. Therefore in this study, an extensive work is conducted to investigate the impact of Cu(II)-doping on the susceptibility of Escherichia coli ATCC 10536 against Cu(II)-selective Cefaclor-silver nanoconjugates (i.e., Cf-AgNPs) and its organic precursor (i.e. Cefaclor). At first, the maximal non-cytotoxic dose of Cu(II) that was sub-lethal for Escherichia coli was determined by MTT assay and was found to be 100 μg/L. Afterwards, MICs of Cf-AgNPs and Cefaclor against controlled and Cu(II)-doped E. coli cells were determined by using Agar well diffusion method. The susceptibility of E. coli cells against Cf-AgNPs was increased upon Cu(II) doping, whereas the bactericidal activity of Cefaclor against Cu(II)-doped E. coli cells was retarded due to hydrolysis. In addition, morphological changes induced in controlled and Cu(II)-doped samples of E. coli after treatment with Cefaclor and Cf-AgNPs were also monitored by Atomic force microscopy (AFM). The obtained results from both Agar well diffusion method and AFM confirmed that Cf-AgNPs are more effective against Cu(II)-doped Escherichia coli. Moreover, thermal profile of Cu(II)-selective Cf-AgNPs was also demonstrated by TGA and DSC. This study can be an important part of the relevant state-of-the-art. Indeed, further clinical studies are necessary to determine the relevant role of Cf-AgNPs compared with that of the Cefaclor now available.

Assessment of intake of copper and lead by sheep grazing on a shooting range for small arms: a case study.

The Norwegian Armed Forces' shooting ranges contain contamination by metals such as lead (Pb) and copper (Cu) and are often used as grazing pastures for livestock. To determine whether the sheep were at risk from grazing at a shooting range in Nord-Trøndelag (the Leksdalen shooting field), a study was conducted wherein the aim was to determine the amount of soil the sheep were eating, the accumulation of Cu and Pb in the livers of lambs grazing on the shooting ranges, and the accumulation of Pb and Cu in the grass. The grazing behavior of the sheep was mapped using GPS tracking and wildlife cameras. Soil, grass, feces, and liver samples were collected. All the samples were analyzed for Pb, Cu, and molybdenum (Mo), and soil and feces were also analyzed for titanium (Ti). Mean concentrations in grass, soil, feces, and liver was 41-7189, 1.3-29, 4-5, and 0.3mg/kg Pb, respectively, and 42-580, 4.2-11.9, 19-23, and 273mg/kg Cu, respectively. The soil ingestion rate was calculated using Ti in feces and soil. From these results, the theoretical dose of Cu and Pb ingested by grazing sheep was calculated. The soil ingestion rate was found to be 0.1-0.4%, significantly lower than the soil ingestion rate of 5-30% usually used for sheep. Little or no accumulation of Cu and Pb in the grass was found. There was no difference between the metal concentrations in the washed and unwashed grass. According to the calculated dose, the sheep were at little or no risk of acute or chronic Pb and Cu poisoning from grazing on the Leksdalen shooting range. The analysis of liver samples showed that lambs grazing on the shooting range did not have higher levels of Cu or Pb than lambs grazing elsewhere. None of the lambs had concentrations of Cu or Pb in their livers indicating poisoning.

Trace element repletion following severe burn injury: A dose-finding cohort study

Major burn patients are characterized by large exudative losses of Cu, Se and Zn. Trace element (TE) repletion has been shown to improve clinical outcome. Having increased the TE doses over time, the study aimed at analysing if our repletion protocol corrected TE plasma concentrations and if the necessity for continuous renal replacement therapy (CRRT) might increase the TE needs. Retrospective analysis of prospectively collected data in burn patients requiring intensive care (ICU) between 1999 and 2015. Admission on day 1, full treatment, burned surface area (TBSA) ≥20% and ≥1 TE plasma determination during the stay. Four groups were constituted according to protocol changes. Period 1 (P1): 1999-2000, P2: 2001-2005, P3: 2006-2010, P4: 2011-2015. Changes consisted in increasing TE repletion doses and duration. Demographic data, daily TE intakes and weekly plasma concentrations were retrieved for the first 21 ICU-days. Data as median (IQR). 139 patients completed the criteria, aged 37 (28) years, burned on 35 (25) % TBSA. As a result of prescription, Cu, Se and Zn intakes increased significantly between P1 and P4, resulting in normalization of plasma Cu (16μmol/l) since P3 and Zn (13.5μmol/l) since P2. Median plasma Se were above reference range (1400nmol/l) during P3 and P4. CRRT patients required higher doses of Cu for maintenance within normal ranges. This dose finding study shows that the latest repletion protocol is safe and normalizes Cu and Zn concentrations. Se doses result in supra-normal Se concentrations, suggesting prescription reduction. CRRT patients are at high risk of Cu depletion and require specific monitoring.

Application of Mineral‐Based Amendments for Enhancing Phytostabilization in Lolium perenne L. Cultivation

An experimental investigation is conducted to explore the suitability of Lolium perenne L., diatomite, chalcedonite, dolomite, and limestone for the phytostabilization of Ni and Cu in contaminated soil. A controlled greenhouse study is conducted. The soil is enriched with rising dose of Cu and Ni, that is, (0, 150, 250, and 350 mg kg−1) and (0, 150, 300, and 450 mg kg−1), respectively. The phytostabilization potential of perennial ryegrass is evaluated using a bioaccumulation coefficient and translocation factor. Pseudo‐total and available metal content (0.01 M CaCl2) in soils and bioaccumulated content in plants are defined in laboratory experiments using spectrophotometry experimental technique. L. perenne is adequate in phytostabilization aided programs, simultaneously, diatomite, chalcedonite, dolomite, and limestone used as modifiers are effective in reducing the accessibility and mobility of metals in Cu‐ and Ni‐polluted soils. The finding of the present study suggests that the studied element in the roots and above‐ground parts of L. perenne differs significantly upon applying mineral‐based modifications to the soil, synchronously the effect of increasing Cu and Ni levels. Application of dolomite and limestone to the soil cause the highest percentage of the above‐ground biomass. Diatomite along with limestone cause a significant boost of Cu and Ni absorption in the roots. Limestone causes an increase in the contents of K, Na, and Ca, as well as a reduction in P in the above‐ground parts of L. perenne. Limestone and chalcedonite leads to the highest decrease in available Cu and Ni.

Effect of copper on the translocation and transformation of polychlorinated biphenyls in rice

Contamination of organic pollutants in the environment is usually accompanied by heavy metals. However, a little information on the influences of heavy metals on the uptake, translocation and transformation of organic pollutants in plants is available. In this study, ten-day hydroponic exposure was conducted to explore the influence of copper (Cu) on the bioaccumulation and biotransformation of polychlorinated biphenyls (PCBs) in intact young rice (Oryza sativa L.). Low dose of Cu (≤100 μmol/L) increased the accumulation of CB-61 in rice plants, while excess concentrations of Cu (>100 μmol/L) inhibited uptake and translocation of CB-61. Effect of Cu on the uptake of CB-61 was attributed to the Cu-triggered damage to the roots of rice plants. The presence of a moderate dose of Cu (50 μmol/L) enhanced the formation of hydroxylated polychlorinated biphenyls (OH-PCBs) and methoxylated polychlorinated biphenyls (MeO-PCBs), whereas excess concentrations of Cu (250 μmol/L) inhibited the metabolism of CB-61. The effect of Cu on the interconversion between 4′-OH-CB-61 and 4′-MeO-CB-61 was also concentration dependent: the biotransformation was promoted by a moderate concentration of Cu but inhibited by excess concentrations of Cu. The activities of Cytochrome P450 (CYP450) and S-adenosyl-l-methionine (SAM)-dependent methyltransferase in the roots of rice plants exposed to Cu and CB-61 or its derivatives were consistent with the pattern and trend of the metabolites observed in rice roots. These results could provide valuable insights into the interactions and combined effects of PCBs and heavy metals in plants.

Chloride-enhanced oxidation of organic contaminants by Cu(II)-catalyzed Fenton-like reaction at neutral pH

The Cu(II)-catalyzed Fenton-like reaction was found to be significantly accelerated in the presence of chloride ion (i.e., the Cu(II)/H2O2/Cl− system), enhancing the oxidative degradation of organic contaminants at neutral pH. The degradation of carbamazepine (a select target contaminant) by the Cu(II)/H2O2 system using 1μM Cu(II) and 10mM H2O2 was accelerated by 28-fold in the presence of 10,000mg/L Cl− at pH 7. The observed rate of carbamazepine degradation generally increased with increasing doses of Cu(II), H2O2, and Cl−, and exhibited an optimal value at around pH 7.5. Various other organic contaminants such as propranolol, phenol, acetaminophen, 4-chlorophenol, benzoic acid, and caffeine were also effectively degraded by the Cu(II)/H2O2/Cl− system. Experiments using oxidant probe compounds and electron paramagnetic spectroscopy suggested that cupryl (Cu(III)) species are the major reactive oxidants responsible for the degradation of these organic contaminants. The enhanced kinetics was further confirmed in natural seawater.

Response at Genetic, Metabolic, and Physiological Levels of Maize (Zea mays) Exposed to a Cu(OH)2 Nanopesticide

Nanopesticides are becoming more popular in modern agriculture to improve crop protection product efficacy. However, information on their implications for crop plants is needed. In this study, 3-week-old maize plants were exposed to different doses of Cu(OH)2 nanopesticide (0, 10, and 100 mg) for 7 days via foliar application. Gene expression of 9 antioxidant-related enzymes (CAT1, POD1, GST1, SOD-1A, SOD-B, GPX, APX1, HSP1, PER1) was determined using a quantitative real-time polymerase chain reaction. Using gas chromatography time-of-flight mass spectrometry, levels of 12 low-molecular-weight antioxidant compounds were measured. Results showed that a dose of 100 mg of Cu(OH)2 nanopesticide significantly decreased leaf chlorophyll content and biomass by 17–20%. In addition, potassium and phosphorus were up-regulated (14% and 13%, respectively) in response to this dose. Gene expression of POD1 and GST1 was significantly (p < 0.05) increased by 42.6% and 71.8%, respectively, at a dose of 10 mg, but declined...

Impacts of EDTA on uptake and accumulation of Cu 2+ by spinach ( Spinacia oleracea L.) seedlings replanted in hydroponic solutions

The effects of EDTA on Cu 2+ uptake by spinach ( spinacia oleracea L) seedlings replanted in hydroponic solutions in a greenhouse were investigated. Four week old seedlings were exposed to various doses of Cu 2+ (0, 5, 10, 15, and 20mg/L) and constant concentration of EDTA (10mM). During the exposure, the plant protected itself from the damage caused by Cu 2+ uptake by using the antioxidant,(proline). The photosynthetic pigments (i.e. chlorophyll a , chlorophyll b and Carotenoid) gradually declined. In this study, dry weights and lengths of roots, shoots and contents of the photosynthetic pigments of both chelated and unchelated hydroponic treatments were investigated. Changes in photosynthetic pigments, root and shoot weights and lengths were significant ( p < 0.05 ) with respect to addition of EDTA to different concentrations Cu 2+ compared to unchelated treatments of same Cu 2+ concentrations. Hence, chelation enhanced Cu 2+ uptake with adverse effects on the plant. Keywords: Photosynthetic, Chlorophyll, Chelation, Spinach, Hydroponic, Greenhouse

Sensitivity of two green microalgae to copper stress: Growth, oxidative and antioxidants analyses

Depending on species, heavy metals, including copper (Cu), differentially affect algal growth and metabolism. Here, we aim to evaluate the differential responses of two green microalgae, Chlorella sorokiniana and Scenedesmus acuminatus, exposed to sub-lethal doses of Cu (25 and 50µM, respectively) for 7 days. The changes in growth, oxidative damage markers, and antioxidants were analysed. We found that S. acuminatus could acclimatise during long-term exposure to Cu stress. S. acuminatus accumulated lower Cu content and showed a slight decrease in H2O2 levels when compared to C. sorokiniana. Cu stress induced membrane damage in the two microalgae species, however, this increase was slightly lower in S. acuminatus. To mitigate Cu stress impact, C. sorkiniana markedly increased proline, polyphenols, flavonoids, tocopherols, glutathione levels, as well as the activities of GST, APX, GR and SOD enzymes, which could explain less-stress sensitivity. On the other hand, S. acuminatus exhibited significant increases in proline, polyphenol, and tocopherol contents. Activity levels of POX, APX, GR and SOD enzymes, were also increased. These results suggest that the two microalgae differentially induced the antioxidant defence system to neutralise the oxidative damage induced by Cu stress. This study also provided new data for Cu tolerance and Cu removal abilities of two microalgal species, which commonly exist in surface water bodies, where low Cu uptake and efficient antioxidant defence system protected S. acuminatus against oxidative stress induced by Cu stress. This makes it feasible for treatment of Cu contaminated waters.

Variation in Copper Accumulation at the Tissue Level of Five Hybrid Poplars Subjected to Copper Stress

Heavy metal contamination causes significant environmental problems around the world and poses a threat to human health. Poplar hybrids present features for potential uses in phytoremediation systems in areas with heavy metal contamination. The purpose of this study was to assess the copper (Cu) accumulation level in five poplar inter-species hybrids [(Populus trichocarpa × Populus deltoides) × P. deltoides; P. deltoides × Populus nigra; P. trichocarpa × Populus maximowiczii; P. trichocarpa × P. nigra; and (P. trichocarpa × P. deltoides) × (P. trichocarpa × P. deltoides)] grown in a hydroponic system. The treatments entailed the application of low and high doses of Cu of 8.0 and 16.0 μM, respectively. Cu accumulation was observed in roots, stems, and leaves, which was determined using flame atomic absorption spectroscopy, prior acid digestion of each sample. The methodology was validated according to certified reference material (Cypress BIMEP 432). Significant differences in Cu accumulation were found among genotypes for both roots and leaves, but not for stems. In roots, the genotype P. deltoides × P. nigra had a Cu accumulation level of 169.8% higher than the average accumulation found in the other genotypes. The (P. trichocarpa × P. deltoides) × P. deltoides hybrid showed the least Cu accumulation in leaves. The results of this study can potentially be used for proper crossovers and hybrids selection within the genus Populus for phytoremediation of Cu contaminated land.

Tolerance and translocation of heavy metals in young grapevine (Vitis vinifera) grown in sandy acidic soil with interaction of high doses of copper and zinc

Vineyard soils may have high levels of copper due to frequent applications of Bordeaux mixture for the control of fungal diseases. Therefore, many winegrowers have used zinc-based fungicides instead of copper-based fungicides, resulting in high levels of Cu and Zn in vineyard soils. The aim of the study was to evaluate the tolerance of young grapevines grown in soil with interaction of high contents of Cu and Zn, and the translocation of these heavy metals from roots to shoots. We collected soil of a natural field of Rio Grande do Sul, the southernmost state of Brazil. Soil treatments were addition of 0, 30, and 60mg Cu kg−1, and addition of 0, 15, 30, 60, 120, and 180mg Zn kg−1 for each copper dose. A seedling of grapevine per pot was grown for 60days. After that, we measured root and shoot dry matter, Cu and Zn content in roots and shoots, chlorophyll a fluorescence, photosynthetic pigments, and peroxidase and superoxide dismutase activity. Young grapevines showed tolerance mechanisms to high concentrations of Cu and Zn by retaining these metals in the roots, decreasing translocation to the shoots. However, at the highest doses of Cu and Zn, we observed decrease in plant growth and in photochemical efficiency associated with the decrease in photosynthetic pigment content. Furthermore, the activity of antioxidant enzymes increased in intermediate doses of Zn, which indicates activation of the antioxidant system. However, the stress condition in treatments with high levels of Cu and Zn was not reversed.

Comparison of the effect of dietary copper nanoparticles with copper (II) salt on bone geometric and structural parameters as well as material characteristics in a rat model

Copper is required for normal functioning of all basic biochemical and physiological processes in the body. The objective of this study was to compare the effect of two different chemical forms (carbonate and nanoparticles) of Cu administered in feed mixtures to growing rats on bone geometric and structural parameters as well as material characteristics in a rat model. For this purpose, five experimental treatments were used to evaluate the effects of different levels of Cu applied in the diet as a mineral mixture (the standard dose of 6.5mg/kg diet, half the standard dose, and no Cu in mineral mixture as a negative control) and two Cu sources (CuCO3 – commonly used in rodent laboratory diets and a Cu-NP nanoparticle preparation, 40nm). There were no changes in body weight and bone morphology, but significant alteration was noted in the geometry and mechanical parameters, which was Cu-NP-dose dependent. Our study showed an increase in the ultimate load and toughness in Cu-NP-treated rats at the standard concentration. The higher values of the studied parameters prove that there was a change in bone mineralization. Although bone mineral density and content were not changed, bone tissue density and ash increased. The XRD analysis revealed that some peaks did not originate from hydroxyapatite, and they indicated existence of other mineral phases. No studies conducted so far have provided a detailed mechanical X-ray diffraction analysis of bone tissue of growing rats administered with diet containing Cu nanoparticles. This study showed that Cu-NP given in low dose increased mechanical endurance of bone, without the changes in strain and stress compared to low dose of Cu given in traditional form.

Inducement of apoptosis by cucurbitacin E, a tetracyclic triterpenes, through death receptor 5 in human cervical cancer cell lines

Cervical cancer is the most common malignancy in women, for which conization or hysterectomy are the main therapy. Curcubitacin E (Cu E) is a natural compound-based drug which from the Guadi (climbing stem of Cucumic melo L). Previously shown to be an anti-tumor as well as a potent chemopreventive agent against several types of tumors. The present study, investigated anti-proliferation and apoptosis induced by Cu E in cervical cancer cell lines (HeLa and Ca Ski). The results indicate that the cytotoxicity is associated with accumulation in apoptosis but not necrosis. Cu E produced apoptosis as well as the up-regulation the expression of death receptor 5 (DR5). In addition, the DR5 gene activation in apoptosis, both effects increased proportionally with the dose of Cu E; however, mitosis delay was also dependant on the amount of Cu E treatment in the cancer cells. These results indicate that Cu E may delay cancer cell growth by apoptosis via upregulation of DR5 gene expression.

Avaliação do potencial fitorremediador de crisântemo em solo com excesso de cobre

Minimizing the harmful effects of copper (Cu) in the soil, using plants are slow and gradual, requiring the identification of species with fitorremediativa fitness for this process. Thus, the present work had as objective to evaluate the cultivation of chrysanthemum cv. Dark Fiji in soil added with Cu as promising phytoremediation. The experiment was conducted in the period from July to December 2014, in the greenhouse of the Floriculture UFSM. In a completely randomized experimental design, with five treatments composed of doses of Cu added to the soil, in the amounts of 250, 500, 750 and 1,000 mg kg-1 and control (without addition), with five replications. In two crop cycles both with duration of 104 days from the production of seedlings to harvest. Chrysanthemum cuttings were obtained from cuttings collected in the garden clonal itself, with 8 cm long, rooted in commercial substrate and transplanted into containers containing soil. They evaluated phytotechnical parameters and translocation factors of aerial part of bioaccumulation and bioconcentration factor of Cu in plant roots and metal extraction rate. It was observed that at all doses of Cu added to the soil, the plants showed low plant development and floriferous affecting its aesthetic quality in both crop cycles. The high accumulation of Cu in the roots is indicative of growing tolerance, cv. Dark Fiji in areas with excess of this, with phytoremediation potential.

Expression analysis of metallothioneins and mineral contents in tomato (Lycopersicon esculentum) under heavy metal stress.

Heavy metals are considered to be the most important pollutants in the contamination of soils; they adversely affect plant growth and development and cause some physiological and molecular changes. The contamination of agricultural soils by heavy metals has changed the mineral element content of vegetables. Plant metallothioneins (MTs) are thought to have the functional role in heavy metal homeostasis, and they are used as the biomarkers for evaluating environmental pollution. We aimed to evaluate the expression of MT isoforms (MT1, 2, 3 and 4) and some mineral element composition of tomato roots, leaves and fruits exposed to copper and lead. Heavy metal applications increased MT1 and MT2 gene expressions compared to the control in the tissues of tomato. The highest level of MT1 and MT2 transcripts was found in roots and leaves, respectively. The expression of MT3 is induced in roots, leaves and fruits except for Pb treatment in roots. MT4 expression increased in fruits; however, other tissues did not show a clear change. Our results indicated that Cu content was higher than Pb in all tissues of tomato. The lower doses of Cu (10 ppm) increased the content of Mg, Fe, Ca and Mn in roots. Pb generally increased the level of minerals in leaves and fruits, but it decreased Mg, Mn and Fe contents in roots. Both heavy metals not only moved to aerial parts but also caused alterations to mineral element levels. These results show that MT transcripts are regulated by Cu and Pb, and expression pattern changes to MT isoforms and tissue types. © 2016 Society of Chemical Industry.

Black Oat (Avena strigosa Schreb.) Growth and Root Anatomical Changes in Sandy Soil with Different Copper and Phosphorus Concentrations

Successive applications of copper-based (Cu) fungicides have increased Cu concentration in vineyard soils, inducing Cu toxicity in young vines and cover crops such as black oat, thus inhibiting growth and development. However, increasing soil phosphorus (P) content can reduce Cu toxicity symptoms. In this context, the aim of this study was to evaluate the effect of Cu toxicity and its alleviation by P fertilization in black oat cultivated in sandy soil. For the experiment, Typic Hapludalf soil samples were air-dried, prepared, and subjected to increasing doses of Cu (0, 30, and 60 mg kg−1) and P (0 and 100 mg kg−1). Subsequently, the soil was incubated and stored in pots, where black oat seedlings were grown for 30 days in a greenhouse. Plant roots subjected to Cu, especially with the highest Cu concentration and without P addition decreased the root cap size, showing early tissue differentiation and lateral root formation near the apical region. Decrease in dry matter (DM) production of roots (50 %) and shoots (67 %) was also observed in the highest Cu concentration. Plants without P addition, regardless of Cu concentration, also had lower root (33 %) and shoot (65 %) DM production. P addition in soil and its increased concentration reduced root anatomical changes and stimulated plant DM production. Therefore, we conclude that excessive Cu concentration alters black oat root anatomical structure, affecting plant growth, especially in sandy soils with low organic matter content. However, P supply can reduce root Cu toxicity symptoms, thus increasing plant dry matter production.

Physiological and nutritional status of black oat (Avena strigosa Schreb.) grown in soil with interaction of high doses of copper and zinc

Vineyard sandy acid soils from South Brazil have experienced heavy metal contamination due to replacement of copper (Cu)-based by zinc (Zn)-based products to control foliar diseases. Thus, we evaluate physiological and nutritional status of black oat (Avena strigosa Schreb.), a common interrow crop in vineyards from this region. Soil was collected in a natural field from Santana do Livramento, in Rio Grande do Sul, the southernmost state of Brazil. Black oat was cultivated for 30 days in a greenhouse with application of 0, 30, and 60 mg Cu kg−1 combined with 0, 15, 30, 60, 120, and 180 mg Zn kg−1. After the trial period, dry matter accumulation of roots and shoots, Cu and Zn contents in roots and shoots, chlorophyll a fluorescence, photosynthetic pigments and catalase (CAT, EC 1.11.1.6) and peroxidase (POD, EC 1.11.1.7) activity were determined. Cu and Zn toxicity was evidenced by the decrease in plant growth of black oat as well as by the decrease of photochemical efficiency associated with the decrease in photosynthetic pigment content, especially with the highest doses of Cu and Zn. Furthermore, the activity of antioxidant enzymes (CAT and POD) was increased in intermediate doses of Zn, indicating the activation of the antioxidant system, but the stress condition in treatments with high levels of Cu and Zn was not reversed.

Effects of zinc addition to a copper-contaminated vineyard soil on sorption of Zn by soil and plant physiological responses

The occurrence of high levels of Cu in vineyard soils is often the result of intensive use of fungicides for the preventive control of foliar diseases and can cause toxicity to plants. Nowadays many grape growers in Southern Brazil have replaced Cu-based with Zn-based products. The aim of the study was to evaluate whether the increase in Zn concentration in a soil with high Cu contents can interfere with the dynamics of these elements, and if this increase in Zn may cause toxicity to maize (Zea mays L.). Soil samples were collected in two areas, one in a vineyard with more than 30 years of cultivation and high concentration of Cu and the other on a natural grassland area adjacent to the vineyard. Different doses of Cu and Zn were added to the soil, and the adsorption isotherms were built following the Langmuir's model. In a second experiment, the vineyard soil was spiked with different Zn concentrations (0, 30, 60, 90, 180, and 270mg Zn kg−1) in 3kg pots where maize was grown in a greenhouse for 35 days. When Cu and Zn were added together, there was a reduction in the quantities adsorbed, especially for Zn. Zn addition decreased the total plant dry matter and specific leaf mass. Furthermore, with the increase in the activity of catalase, an activation of the antioxidant system was observed. However, the system was not sufficiently effective to reverse the stress levels imposed on soil, especially in plants grown in the highest doses of Zn. At doses higher than 90Znmgkg−1 in the Cu-contaminated vineyard soil, maize plants were no longer able to activate the protection mechanism and suffered from metal stress, resulting in suppressed dry matter yields due to impaired functioning of the photosynthetic apparatus and changes in the enzymatic activity of plants. Replacement of Cu- by Zn-based fungicides to avoid Cu toxicity has resulted in soil vineyards contaminated with these metals and damaging of plant photosynthetic apparatus and enzyme activity.

A novel class of copper(II)- and zinc(II)-bound non-steroidal anti-inflammatory drugs that inhibits acute inflammation in vivo.

BackgroundThe ability of Zn(II) and Cu(II) metal complexes of non-steroidal anti-inflammatory drugs (NSAIDs) to inhibit acute arterial inflammation in vivo has been studied. ResultsWhen acute vascular inflammation was induced in normocholesterolemic New Zealand White rabbits by inserting a non-occlusive silastic collar around the common carotid artery, a single oral dose of Cu(II)-indomethacin (Cu(II)Indo, 3 mg/kg) administered by laparotomy achieved a 67 % (8.2 ± 1.7 vs. 2.7 ± 0.4 image units, p < 0.05) reduction in endothelial expression of vascular cell adhesion molecule-1 (VCAM-1) but did not inhibit endothelial intercellular adhesion molecule (ICAM-1) expression significantly. Treatment with Cu(II)-acemetacin (Cu(II)ACM, 3 mg/kg) led to a profound 88 % (8.2 ± 1.7 vs. 1.0 ± 0.5 image units, p < 0.01) reduction in endothelial VCAM-1 expression but did not inhibit ICAM-1 expression, while treatment with Zn(II)-acemetacin (Zn(II)ACM, 3 mg/kg) led to an 84 % (19.3 ± 1.0 vs. 3.1 ± 1.2 image units, p < 0.01) reduction in endothelial ICAM-1 expression and did not inhibit VCAM-1 expression. No adverse gastric, hepatic or renal effects were observed in treated animals. ConclusionThese findings provide the “proof of concept” that this novel class of drug, where there is complexation of NSAIDs with metal ions, has substantial anti-inflammatory effects in an animal model of acute vascular inflammation with the possibility of low rates of adverse effects.

Copper phytoremediation potential of Calandula officinalis L. and the role of antioxidant enzymes in metal tolerance

Cu phytoremediation potential of an ornamental plant, Calandula officinalis, was explored in terms of growth responses, photosynthetic activities and antioxidant enzymes such as SOD, CAT and GPX. The results showed that this plant had high Cu tolerance of up to 400mg/kg, which is far above the phytotoxic range for non hyperaccumulators. It grew normally in soils at all the doses (150–400mg/kg) without showing external signs of phytotoxicity. At 150mg/kg, flowering was augmented; root and shoot biomass, root lengths and leaf soluble protein contents remained same as that of the control. However, chlorophyll and carotenoid pigment contents declined significantly along with significant elevations in lipid peroxidation, at all the doses. Elevations of antioxidant enzymes reflected stress as well as probable mitigation of reactive oxygen species due to Cu stress. Except for the highest conc. (400mg/kg), leaf accumulation of Cu was higher than root accumulations. The Cu accumulation peaked at 300mg/kg Cu in soil, with leaf and root accumulations to be respectively, 4675 and 3995µg/g dry wt., far more than the minimum of 1000µg/g dry wt. for a Cu hyperaccumulator. The plant root at all the doses tolerated Cu, with the tolerance index ranging from 94–62.7. The soil to plant metal uptake capacity, indicated by extraction coefficient and the root to shoot translocation, indicated by translocation factor, at all the doses of Cu were >1, pointed towards efficient phytoremediation potential.