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1.
Summary Experiments on sitka-spruce seedlings grown in acidic peaty gley soils under green-house conditions, where the soils where doped with increasing amounts of Cd, Cu and Pb up to maximum levels of metal added of 16 ppm, 32 ppm and 400 ppm respectively, showed that the levels of Cd and Pb in shoots and roots increased with increasing levels in the soil, whereas levels of copper appeared to be independent. The addition of these three metals to the soils did not influence the uptake of other heavy metals, or of the nutrients potassium or calcium. Increases in the shoot cadmium levels significantly reduced the yields of the plant shoots. However, the plant yields were only affected by the highest level of lead that was added to the soil (400 ppm Pb) and unaffected by all the copper treatments (0–32 ppm Cu in the soil). The lengths of the sitka-spruce roots were reduced when cadmium and lead levels in the soil exceeded certain threshold concentrations (2.5 ppm total Cd, where 0.3 ppm was extractable with 0.5 M acetic acid; and 48 ppm total Pb, where 1.7 ppm was extractable). However, root lengths were not reduced by copper. This was probably related to the fact that copper appears to be relatively unavailable in the type of soil used, as only 1.1. ppm Cu was extractable from a total of 32 ppm Cu added. Root branching was apparently reduced by increases in the soil levels of cadmium, copper and lead. The roots of some control plants had symbiotic mycorrhizal associations (4 out of 19 plants), whereas the roots of all the plants grown in the soils with added heavy metals did not develop these.  相似文献   

2.
The vegetation of two copper clearings at Tenke Fungurumi in Zaire is described. The copper content ol the soil varied between 1000 to 130,000 ppm. Areas of highest soil copper (above 6–7000 ppni) were colonized primarily by grasses particularly Eragrostis boehmii, Sporobolus rangei and Loudetia simplex but also by other specialized cupriferous species including Becium aureoviride, Dasystachys pulchella, Anisopappus hoffmannianus and Pandiaka metallorum. Soils with 1000 to 7000 ppm copper were colonized by a community dominated by Loudetia simplex and a morphologically distinct form of Cryptosepalum maravieme. The percentage cover of Cryptosepalum was negatively correlated with soil copper. Uapaca robynsii , the most copper-tolerant woody plant, grew below 1500 ppm copper and was normally replaced by other species below approximately 1000 ppm.
The gross morphology oi Xerophyta equisetoides on three sites at Dikuluwe was investigated in relation to the soil characteristics. The growth form on Dikuluwe Hill (11,000 to 111,000 ppm copper) and a nearby non-cupriferous hill (100–200 ppm copper) were basically similar, although the morphology of the Dikuluwe Hill population was probably affected by soil copper and water stress. A distinct morphological form grew on a cupriferous (4000–5000 ppm copper) dembo site.  相似文献   

3.
The present study was focused on synthesis and characterization of copper nanoparticles to evaluate their efficacy against fruit rot pathogen of chilli crop. The green synthesis of nanoparticles was carried out by using extracts of Eucalyptus and Mint leaves. The synthesis of copper nanoparticles was confirmed by XRD, PSA, SEM and TEM. The average size of these particles synthesized by Eucalyptus leaf extract (CuNP-E) ranged from 10 to 130 nm, while as size of Mint leaf extract synthesized particles (CuNP-M) ranged from 23 to 39 nm, thus confirming their nano size. These green synthesized copper nanoparticles were evaluated against Colletotrichum capsici where Carbendazim 50 WP @ 500 ppm and copper oxychloride 50 WP @ 2500 ppm served as standard checks. The mycelia inhibition of Colletotrichum capsici caused by copper nanoparticles was studied on PDA medium. CuNP-M @ 1000 ppm showed highest mycelial inhibition of 99.78% followed by 93.75% at 500 ppm and CuNP-E @ 1000 ppm compared to standard fungicides, carbendazim 50 WP @ 500 ppm (72.82%), and copper oxychloride 50 WP @ 2500 ppm (85.85%). The CuNP-M @ 500 ppm were significantly superior to carbendazim 50 WP @ 500 ppm and copper oxychloride 50 WP @ 2500 ppm, but was statistically at par with CuNP-E @ 1000 ppm. This shows effectiveness of much lower concentration of copper nanoparticles compared to conventional fungicides. In detached fruit method, nanoparticles applied before inoculation of pathogen showed better results with regard to incubation period, lesion number and lesion size than after inoculation of pathogen. The present study reveals a simple, convenient, non-toxic and cost-efficient technique for the synthesis of nanoparticles and their effectiveness against Colletotrichum capsici. CuNP-M first time synthesized and evaluated against Colletotrichum capsici performed better than CuNP-E.  相似文献   

4.
Three groups (14 rats each) were fed one of the following diets for 8 wks: a control purified basal diet containing 12 ppm zinc, 5 ppm copper, and 35 ppm iron; the basal diet with less than 2 ppm zinc; or the basal diet supplemented with 1000 ppm zinc. Rats fed the zinc-deficient diet had decreased weight gain, moderate polydipsia, and intermittent mild diarrhea. The zinc-supplemented rats had a cyclical pattern of food intake and weight loss from weeks 5 to 8. Tissue concentrations suggest that zinc and copper were not mutually antagonistic with chronic dietary imbalances. If tissue element concentrations reflected intestinal uptake, then competition and/or inhibition of intestinal uptake occurred between zinc and iron. The fluctuations in tissue element concentrations that occurred with increased duration of the study were at variance with previous studies of shorter time periods. The dietary proportions of zinc, copper, and iron appear to influence zinc, copper, and iron metabolism at the intestinal and cellular transport levels over a given period of time.  相似文献   

5.
Methodologies were developed which provided resolution of deuterium oxide in water and sublimates of biological fluids to ±1 ppm over the range of background to 1000 ppm added D2O. These procedures involve a simple rapid sublimation procedure with infrared analyses, at 4.0 μm, using a simple Wilks infrared analyzer and 0.2-mm calcium fluoride cells with cell temperature regulated to ±0.005°C.  相似文献   

6.
M. Ugarte  K. Geraki  G. Jeffery 《Biometals》2018,31(6):1061-1073
We present further analyses of a previous experiment published in 2016 where the distribution, concentration and correlation of iron, zinc, copper and sulphur in the choroid of the eye in young and aged old world primates (Macaca fascicularis) was studied with synchrotron X-ray fluorescence with a 2 μm resolution. The results indicate that iron accumulates in hotspots in the choroid with age with fluorescence intensity ranging from 2- to 7-fold (1002–3752 ppm) the mean level in the choroidal stroma (500 ppm) and maximum iron levels in blood vessel lumina. Iron hotspots with iron ppm?>?1000 preferentially contained Fe3+ as demonstrated by Perls staining. There was a strong spatial co-localisation and correlation between copper and zinc (Pearson’s correlation coefficient 0.97), and both elements with sulphur in the choroid of young animals. However, these are reduced in the choroid of aged animals and lost in the iron hotspots. The lack of proportional co-distribution suggests that iron accumulation does not induce a concomitant increase in zinc, copper or zinc-, copper-metalloproteins. It is possible that the iron hotspots are ferritin or hemosiderin molecules loaded with Fe3+ in stable, insoluble, non-toxic complexes without a significant oxidative environment.  相似文献   

7.
Curcumin is a phytochemical with antiinflammatory, antioxidant and anticarcinogenic activities. Apparently, curcumin is not genotoxic in vivo, but in vitro copper and curcumin interactions induce genetic damage. The aim of this study was to test if in vivo copper excess induces DNA damage measured by comet and micronucleus assays in the presence of curcumin. We tested 0.2% curcumin in Balb-C mice at normal (13 ppm) and high (65, 130 and 390 ppm) copper ion concentrations. The comet and micronucleus assays were performed 48 hr after chemical application. Comet tail length in animals treated with 0.2% curcumin was not significantly different from the control. Animals exposed to copper cations (up to 390 ppm) exhibited higher oxidative DNA damage. Curcumin reduced the DNA damage induced by 390 ppm copper. We observed statistically significant increase in damage in individuals exposed to 390 ppm copper versus the control or curcumin groups, which was lowered by the presence of curcumin. Qualitative data on comets evidenced that cells from individuals exposed to 390 ppm copper had longer tails (categories 3 and 4) than in 390 ppm copper + curcumin. A statistically significant increase in frequency of micronucleated erythrocytes (MNE/10000TE) was observed only in 390 ppm copper versus the control and curcumin alone. Also cytotoxicity measured as the frequency of polychromatic erythrocytes (PE/1000TE) was attributable to 390 ppm copper. The lowest cytotoxic effect observed was attributed to curcumin. In vivo exposure to 0.2% curcumin for 48 hr did not cause genomic damage, while 390 ppm copper was genotoxic, but DNA damage induced by 390 ppm copper was diminished by curcumin. Curcumin seems to exert a genoprotective effect against DNA damage induced by high concentrations of copper cations. The comet and micronucleus assays prove to be suitable tools to detect DNA damage by copper in the presence of curcumin.  相似文献   

8.
In the context of the proposed work, two different amino acids (Glycine, Phenylalanine) have interacted with copper ions in a phosphate buffer (PBS) in place of enzymes. This interaction resulted in the nucleation of copper phosphate crystals and the formation of flower-shaped amino acid-copper hybrid nanostructures (AA-hNFs), which grew through self-assembly. While Cu (II) ions in the structure of AA-hNFs were used as Fenton's agent for the catalytic activity. SEM, energy dispersive X-ray spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy measurements were used to define the AA-hNFs′ characterisation. The peroxidase-like activities of AA-hNFs were investigated by UV/VIS spectrophotometer. Metal nanoparticles have peroxidase-like activity. A class of enzymes known as peroxidases is able to catalyze the conversion of hydrogen peroxide into hydroxyl radicals. These radicals also take part in electron transfers with substrates, which results in color during oxidation. When cupric oxide nanoparticles are added to the peroxidase substrate while H2O2 is present, a blue color product with a maximum absorbance at=652 nm can result, demonstrating the catalytic activity of a peroxidase. The morphology and composition of AA-hNFs were carefully characterized and the synthesized parameters were optimized systematically. Results showed that the nanoparticles were dispersed with an average diameter of 7–9 μm and indicated a uniform flower shape. The results of the investigation are anticipated to significantly advance a number of technical and scientific sectors.  相似文献   

9.
A new method for the determination of copper in biological materials by graphite furnace atomic absorption spectroscopy is presented. This new procedure is an extension of the classic method of standard additions, where the analyte concentration is determined in a series of identical samples to which various amounts of metal standard have been added. The concentration of metal in the original sample is determined from an extrapolation of a plot of absorbance versus added analyte. In the new method, the amount of copper is determined by the method of standard additions for different concentrations of the sample under investigation as well. From an extrapolation of the data, the concentration of copper in the absence of interfering matrix is obtained. Studies with fetal bovine serum demonstrate that the new extrapolation technique is precise. Furthermore, considerably more copper is detected than by the classic method of standard additions applied to a nitric acid treated sample. The matrix effects of phosphate, nitrate, albumin, and serum were also examined. Both phosphate and serum, at physiological pH, decrease the detectability of added copper, while nitrate and albumin were without effect. The accuracy of this method has been verified by determining the extinction coefficients of stellacyanin and azurin. The values obtained, 4.33 X 10(3) and 3.75 X 10(3) M-1 cm-1, respectively, are considerably different from those determined by the method of standard additions on nitric acid digests of these proteins, but were close to values previously reported and determined colorimetrically.  相似文献   

10.
Summary Manure from finishing pigs fed diets with and without a growth stimulating level of added copper (250 ppm in 1972, 370 ppm in 1973 and 300 ppm in 1974) was incorporated into a Groseclose silt loam at the rate of 15.5, 12.9 and 15.7 metric tons of dry matter per hectare, respectively, for 1972, 1973 and 1974. A third treatment was no manure. The manure was applied between rows when corn was about 10 cm tall and worked into the surface 10 cm of the soil with a rotary tiller. The average composition of the manure for the three years on a dry basis was 3.6 per cent nitrogen, 2.87 per cent calcium, 0.93 per cent magnesium, 2.22 per cent phosphorus, 1.30 per cent potassium, 648 ppm zinc, 2191 ppm iron. The copper content was 73 ppm for control manure and 1719 ppm for high copper manure. The copper content in the upper 10 cm of the soil was significantly increased each year when high copper manure was applied. During one growing season, copper did not appear to move down, however, plowing after the first year increased the copper level in the 10–20 cm depth with a small increase in the 20–30 cm depth. Potassium, zinc, phosphorus, calcium and magnesium levels of the soil were increased when manure was applied. There was a small increase in the copper content of the maize ear leaf (average of one ppm per year) when manure from pigs fed diets containing high copper was applied. Copper in the washed roots of the mature maize plants was doubled (5.6 vs 11.2 ppm) when the high copper manure was added. The copper content of grain from plants grown on soil receiving high copper manure was not different from that of grain from soil receiving no manure. The zinc, potassium and phosphorus contents of the maize ear leaf were increased a small amount when both control and high copper manure were applied with the effect of potassium and phosphorus carrying over to the grain. The iron and calcium contents of the ear leaf were not affected by application of manure, but there was a decrease in calcium content of the grain from the application of control and high copper manure. re]19750305Department of Animal ScienceDepartment of AgronomyDepartment of Statistics  相似文献   

11.
Summary The effects of adding 100, 1,000, and 10,000 ppm of copper, manganese, zinc and chromium as sulphates and of copper and zinc as carbonates on ammonification and nitrification during incubation (3) weeks) of an initially neutral soil under aerobic and anaerobic conditions were studied. Some stimulating but more usually inhibitory effects of trace elements on both processes were found. These effects varied considerably depending on the level and type of the cation added, whether the conditions were aerobic or anaerobic, and on the extent to which pH was altered by the treatments.  相似文献   

12.
Two 42-d experiments were conducted with weanling male rats to study interactions between nickel and copper. In Experiment 1, a low-copper basal diet was supplemented with copper at 0 or 30 ppm and nickel at 0 or 30 ppm. Copper was added in Experiment 2 to a basal copper-deficient diet at a level of 0 or 15 ppm and nickel was supplemented at 0, 15, or 225 ppm. Responses to dietary nickel were dependent upon copper nutriture and experimental duration. Nickel had little effect on growth during the first 21 d of either study when added at low levels (15 or 30 ppm) to copper-deficient diets. Nickel supplementation depressed gains between 21 and 42 d in rats fed copper-deficient, but not copper-adequate, diets. Hematocrits and hemoglobin concentrations were not significantly affected by dietary nickel at 21 d. Nickel supplementation decreased hematocrits and hemoglobin values in copper deficient rats at 42 d in Experiment 1, but not in Experiment 2. Absorption of copper apparently was not reduced by nickel, since tissue copper concentrations were generally not decreased by increasing dietary nickel. Nickel supplementation increased lung and heart copper concentrations in Experiment 2. Liver iron was not affected by nickel, but spleen iron concentrations were reduced by nickel supplementation in copper-deficient rats in Experiment 2. The present studies suggest that nickel acts antagonistically to copper in certain biological processes.  相似文献   

13.
Soil dilution plates were prepared from different soil samples using a solid synthetic selective medium containing (i). glucose as carbon source, (ii). thymine as nitrogen source, (iii). vitamins, (iv). minerals, and (v). chloramphenicol as antibacterial agent. Using the Diazonium Blue B colour reaction, it was found that both ascomycetous and basidiomycetous yeasts were able to grow on this medium. Subsequently, the medium was used to enumerate yeasts in soil microcosms prepared from four different soil samples, which were experimentally treated with the fungicide copper oxychloride, resulting in copper (Cu) concentrations of up to 1000 ppm. The selective medium supplemented with 32 ppm of Cu was used to enumerate Cu-resistant yeasts in the microcosms. The results showed that the addition of Cu at concentrations >or=approximately 1000 ppm did not have a significant effect on total number of yeasts in the soil. Furthermore, it was found that Cu-resistant yeasts were present in all the soil samples, regardless of the amount of Cu that the soil was challenged with. At the end of the incubation period, yeasts in the microcosms with zero and approximately 1000 ppm of additional Cu were enumerated, isolated, and identified with sequence analyses of the D1/D2 600-650 bp region of the large subunit of ribosomal DNA. Hymenomycetous species dominated in the control soil, while higher numbers of the urediniomycetous species were found in the soil that received Cu. These observations suggest that urediniomycetous yeasts may play an important role in re-establishing overall microbial activity in soils, following perturbations, such as the addition of Cu-based fungicides.  相似文献   

14.
Summary Effect of yeast autolyzate on the growth of vineless pea plant was investigated.The yield was increased remarkably when yeast autolyzate was added, as compared with the control area in which the plants received only mineral fertilizer solution.The yield stimulation was the highest where 0.1 ppm of the autolyzate was added, the yield increasing by more than 80%. The reason why the yields were lower in the areas where the amount of yeast autolyzate added was incrased to 1 ppm and to 10 ppm, was presumed to be due to the fact that the substances may have been absorbed, decomposed, and utilized by soil microorganisms.  相似文献   

15.
Composts were produced from rice straw enriched with rock phosphate and inoculated with Aspergillus niger, Trichoderma viride and/or farmyard manure (FYM). The resulting composts were evaluated as organic phosphate fertilizers for cowpea plants in pot experiments. The results showed that the maximum amount of soluble phosphorous (1000 ppm) was produced in composts inoculated with A. niger+T. viride with or without FYM. Any of the produced composts was much better than superphosphate fertilizer in providing the growing cowpea plants with phosphorous. Fertilization of the cowpea plants with the compost inoculated with FYM+A. niger+T. viride resulted in maximum amount of phosphorous uptake (295 ppm). The highest phosphate dissolving fungi numbers in rhizosphere soils of cowpea plants were obtained after fertilization with composts which received A. niger and T. viride treatments, while the highest phosphate dissolving bacterial numbers were found after fertilization with composts which received FYM treatments.  相似文献   

16.
Bovine monocyte-derived macrophage function in induced copper deficiency   总被引:4,自引:0,他引:4  
The effect of molybdenum-induced copper deficiency on monocyte-derived macrophage function was examined. Five female calves were given molybdenum (30 ppm) and sulphate (225 ppm) to induce experimental secondary copper deficiency. Oxidant production by bovine macrophages was measured after stimulation with phorbol myristate acetate (PMA) and opsonized zymosan (OpZ). Lipoperoxidative effects inside of macrophage, superoxide dismutase activity, superoxide anion and hydrogen peroxide formation were determined. Copper deficiency was confirmed from decreased serum copper levels, and animals with values less than 5.9 micromol/l were considered deficient. The content of intracellular copper decreased about 40% in deficient cells compared with the controls. The respiratory burst activity determined by nitroblue tetrazolium reduction was significantly impaired with both stimulants used. Superoxide anion formation was less affected than hydrogen peroxide generation. In addition, increased lipid peroxidation was observed. It could be concluded that the effect of these changes may impair the monocyte-derived macrophage function in the immune system.  相似文献   

17.
How zinc oxide influences copper release has been tested and the lowest release rate of copper from various combinations of copper and zinc in a paint matrix evaluated, whilst still deterring macrofouling, including barnacles and bryozoans. Copper (I) oxide was added to a generic AF paint in 0, 8.5, 11.7 or 16.3 wt% copper oxide in combination with 0, 10 or 20 wt% zinc oxide and applied on PMMA panels. The results show that zinc influences the release rate of copper. When 10 and 20 wt% zinc was added, the total amount of copper released significantly increased by on average 32 and 47% respectively. All treatments that included copper were successful in deterring macrofouling, including the treatment with the lowest average Cu release rate, ie 4.68 μg cm?2 day?1.  相似文献   

18.
The influence of different doses of boron (100, 500 and 1000 ppm) and cadmium (50, 100, 500, 1000 and 2000 ppm) on the activity of nitrogen fixation in the sandy and alluvial soil has been studied. Almost all doses of boron stimulated this process except 1000 ppm of B added to the sandy soil. All the doses of cadmium also exerted a positive effect on the nitrogen fixation, but only during the first 3 months of the experiment, later (after 12 months) Cd decreased the activity of this process. The most marked effect to the examined elements was pronounced in the sandy soil.  相似文献   

19.
The influence of inoculation with phosphate-solubilizing bacteria (Enterobacter agglomerans) on maize growth, P uptake and root exudation was studied. Plants were grown in an axenic culture device where P was supplied as soluble phosphate at different contents (0, 5, 15 or 25 ppm) in the nutrient solution and as insoluble rock phosphate added to the culture sand. Experimental device was successfully used to obtain axenic root systems or good establishment of the inoculated strain in the rhizosphere of maize (109 bact. g−1 dry rhizospheric material). Plant growth was promoted by inoculation only for 5 or 15 ppm of soluble P in the nutrient medium without any significant effect on P uptake by the plant, suggesting that the quantities of P released by bacterial rhizospheric activity were very small. Amounts of organic compounds (total C and water-soluble C) exuded were relatively low (3.0 to 6.4% of the total plant biomass) and were reduced by bacterial inoculation when plant growth was largely promoted. Carbon balance modification and plant growth hormone production by the inoculated strain were suspected and discussed.  相似文献   

20.
Highest Mg concentration in whole intermoult, 7th growth-stage Porcellio spinicornis, exposed for 7 days to various Mg [367.39 ppb (carrot powder-control), 217.6 ppb (apple powder-control), 100, 150, 500, and 1000 ppm Mg, as well as two mixtures containing 500 ppm Mn + 150 ppm Mg and 500 ppm Mg + 500 ppm Mn)], and Mn concentrations [97.9 ppb (carrot powder-control), 2.0 ppb (apple powder-control), 100, 150, 500 and 1000 ppm)], was observed in males feeding on 500 ppm Mn + 150 ppm Mg, and lowest in females on 500 ppm dietary Mg. Highest tissue Mn concentration, on the other hand, was observed in males exposed to 1000 ppm dietary Mn, and lowest in females on 500 ppm Mg. Approximately 42% of the total tissue Mg was present in hepatopancreas and the remaining in other body tissues, including exoskeleton. In contrast, 78.55% Mn was stored in hepatopancreas and 21.4% in remaining body tissues. Differences between hepatopancreatic Mg levels were not significant between the two sexes, but differences in Mn levels between males and females were significant at P less than 0.01.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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