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1

The toxicity of cerium nitrate to Elodea canadensis: subcellular distribution, chemical forms and physiological effects

100%
Chu W. Y., Cai S. J., Fu Y. Y., Li F. F., Xu T., Qiu H., Xu Q. S.
Acta Physiologiae Plantarum
|
2014
|
tom 36
|
nr 09
The rare earth elements are increasingly being used as trace supplements in different fields. In this study, subcellular distribution, the chemical forms and toxicity of cerium (Ce) were evaluated for Elodea canadensis. The effect of Ce (5–20 mg L⁻¹) applied for 7 days was assessed by measuring changes in the nutrient elements, photosynthetic pigments, malondialdehyde and antioxidant systems. Ce accumulation was greatest in the cell walls, followed by the organelles and the soluble fraction. Ce levels were higher in cellulose and pectin than in other biomacromolecules. The toxic effects caused by Ce were shown by a reduction in photosynthetic pigments, disruption of nutrient elements, and increases in MDA content. E. canadensis shows Ce-induced oxidative stress by modulating antioxidant enzymes, such as guaiacol peroxidase and catalase. Elevated Ce levels may represent a potential risk for aquatic ecosystems.
2

Bioavailability of zinc in different chemical forms for lambs and its influence on copper retention

84%
Slupczynska M., Kinal S.
Polish Journal of Natural Sciences. Supplement
|
2006
|
tom 03
235-241
3

Comparison of the influence of different chemical forms of selenium and the profiles of CLA isomers in the diet on the fatty acid and amino acid contents in the liver and femoral muscles of rats

84%
Czauderna M., Kowalczyk J., Korniluk K., Niedzwiedzka K. M.
Journal of Animal and Feed Sciences
|
2007
|
tom 16
|
nr 4
678-695
4
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Utilization of selenium compounds in nutrition of lambs

84%
Slupczynska M., Kinal S., Hadrys M., Krol B.
Journal of Elementology
|
2009
|
tom 14
|
nr 1
157-163
The level of mineral utilization depends on many factors related to animals as well as to the chemical form of given nutrients. It has been experimentally demonstrated that animals utilize inorganic forms of minerals less efficiently than organic ones. Hence, an attempt has been made to evaluate the bioavailability of selenium bound in different compounds to lambs. Selenium supplementation in fodder mixtures was another aspect included in our tests. Thus, an experiment was conducted on 48 growing lambs, testing the level and chemical forms of selenium in fodder mixtures for animals. In group I (the control) lambs received fodder mixture without any selenium supplement. In the experimental groups, selenium was supplemented as sodium selenite in the amount 0.2 mg Se kg-1 d.m. feeds (II), or selenium enriched yeast (Se-yeast) in the amounts of 0.1 and 0.2 mg Se kg-1 d.m. of feed groups III and IV, respectively. At the end of the experiment, when animals had reached 35 kilos of weight, blood samples were taken. The activity of glutathione peroxidase was estimated in heparinized blood samples. Eight lambs were chosen from each group and killed to collect samples of soft tissues (liver, kidney, brain, muscle). The content of selenium was determined in the tissue samples. Supplementation of feeds for lambs with selenium, both inorganic (sodium selenite) and organic (Se-yeast), increased the content of the element in soft tissues of animals. The highest level of the element was found in the liver and kidneys: 4.65 and 4.90 and 2.10 and 2.30 mg kg-1 fresh tissue, of the lambs receiving sodium selenine and Se-yeast in the amount 0.2 mg Se kg-1 D.M. of feed (groups II and IV), respectively. Selenium compounds added to feeds given to lambs significantly (P£0.01) increased activity of GSH-Px in blood, especially in the case of animals which received yeast enriched with selenium. In blood of the lambs which received feeds with Se-yeast in the amount 0.2 mg Se kg-1 d.m. of feed (group IV), the activity of glutathione peroxidase was by 129.71 U gHb-1 higher, and of the animals which received Se-yeast in the amount 0.1 mg kg-1 d.m. or sodium selenite, the activity of the enzyme was higher by 86.33 and 86.35 U gHb-1, respectively, than the activity of this enzyme in blood of animals from the control group. Supplementation of lambs’ rations with Se in the form of selenite or yeast enriched with selenium forms increased the content of Se in soft tissues and gluthatione peroxidase activity in comparison with animals which did not receive additional doses of this nutrient in fodder mixtures. The availability of Se was more profoundly affected by the amount of the element added rather than its form.
5

Effect of copper supplementation in various chemical forms on the utilization of mineral components and on the health status of turkeys

84%
Makarski B., Zadura A.
Polish Journal of Natural Sciences. Supplement
|
2006
|
tom 03
459-465
6
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Effect of supplementation with copper in different chemical forms on selected physiological blood markers and content of minerals in selected tissues of turkeys

84%
Makarski B., Gortat M.
Journal of Elementology
|
2011
|
tom 16
|
nr 4
Scientific research has demonstrated that different compounds containing copper are capable of stimulating body weight gains, improving the health of animals and attaining high production performance without causing excessive accumulation of various chemical compounds in animal tissues. Besides, copper has been reported to exert a positive effect on the immune system, haematological blood markers and the microbiological balance in the gastrointestinal tract of turkeys. The experiment was conducted on 60 BUT-9 line turkeys. The birds were divided into 5 experimental groups. Each group included 12 turkeys kept in cages. The bird were reared for 19 weeks. The first group served as control. Group II received CuSO4 added to water in a dose of 10 mg Cu dm–3 H2O. Group III was com posed of birds administered a Cu chelate with lysine in a dose of 10 mg Cu dm–3 H2O. Group IV received CuSO4 in a dose of 20 mg Cu dm–3 H2O, whereas group V were given a Cu-lysine supplement in a dose of 20 mg Cu dm–3 H2O. The birds were fed commercial complete feed mixes. The copper preparations were added to drinking water since the 3rd week of rearing. The objective of this study has been to determine the effect of Cu supplementation in the organic and inorganic form and in two doses on the health of birds and on accumulation of minerals in their breast muscle and liver. Further analyses involved the determination of haematological and biochemical markers in blood as well as assays of selected minerals in the birds’ blood, breast muscle and liver. The analysis of the results indicated that the doses of copper improved the health of the turkeys, as verified by better haematological markers. Statistically significant difference appeared in the group receiving 20 mg Cu dm–3 H2O irrespective of the chemical form in which copper was administered. The study also shows that Cu supplementation has a significant effect on the metabolism of lipids and a non-significant impact on the content of mineral elements in the analyzed tissues. It was not until the 20 mg dose of Cu as a chelate had been applied that the accumulation of copper in the turkey’s liver was enhanced.
7

Chemical forms of iron in the composts obtained from municipal solid waste contaminated with pulverized metallic Fe, Fe2O3 or FeS

84%
Ciba J., Zolotajkin M.
Archiwum Ochrony Środowiska
|
2001
|
tom 27
|
nr 1
8

Validation and optimization of conditions for the sequential extraction of manganese from ash

84%
Kalembkiewicz J., Sitarz-Palczak E.
Polish Journal of Environmental Studies
|
2005
|
tom 14
|
nr 1
Methods of sequential extraction are used to determine various chemical forms of metals in environmental samples. With the variety of different sequential extraction procedures used in environmental exploration studies, it is difficult to compare results between studies. The attempt of validation of methods of analysis of chemical fraction of Mn in ashes by FAAS method for two procedures of sequential extraction (BCR and Tessier et al.) was perfomed. It was found that both tested procedures give comparable and reproducible results. The optimal conditions of BCR methods were established, which are: parameters of ash sample (grain diameter – 0.06 mm, drying temperature – 110°C for 24 hrs, mass sample – 1.00 g) and parameters of sequential extraction process (time – 6 hrs, relation of mass of sample to the volume of extraction solution – 1:4). The optimum conditions of sequential extraction of Mn from coal fly ash can be applied in the study of chemical fraction of Mn in fly ash in different research laboratories.
9

Chemical forms and distribution of heavy metals in core sediments from the Gdansk Basin, Baltic Sea

67%
Belzunce S. M. J., Szefer P., Wilson M. J., Bacon J., Bolalek J.
Polish Journal of Environmental Studies
|
2007
|
tom 16
|
nr 4
505-515
Short sediment cores (30 cm length) were taken along a transect of the Gdansk Basin from the mouth of the Vistula River out into the Baltic Sea in June 1996. The chemistry and mineralogy of surficial and buried sediments were determined and Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn were analyzed in total and in fractions using a sequential extraction procedure. The bulk and clay mineralogy of the sediments were determined by XRD and SEM. The concentrations of some of the trace metals in sediments are above pre-anthropogenic background. In particular, the surficial samples are substantially enriched in Cu, Pb and Zn, suggesting an anthropogenic origin. The concentrations of Cu, Pb and Zn range from 21-71 ^g-g"1, 56-210 ^g-g"1 and 21-83 ^g-g-1, respectively. Unexpectedly, the concentrations of trace metals increase seawards within the Gdańsk Basin. The forms of binding are different for each metal. Cobalt, Cr and Fe are mainly associated with the residual mineral fraction of the sediment, although in samples with high Fe concentrations there is a significant correlation with organic compounds. In contrast, Mn, Ni, Pb and Zn are predominantly associ­ated with oxides and the organic fractions, with a significant percentage associated with the carbonate and exchangeable cation fractions, whilst Cu is mainly bound with the organic fraction.
10

Chemical forms of heavy metals in agricultural landscape water

67%
Szpakowska B., Karlik B.
Polish Journal of Environmental Studies
|
1996
|
tom 05
|
nr 6
A procedure for determining the chemical forms of zinc, cadmium, lead and copper in surface and ground waters located in Agricultural Landscape Park (ALP) is outlined. Heavy metals were differentiated into ionic, labile forms and moreover on stable complexes and chelates. In the studied waters, concentrations of ionic forms were 17.9-45.2 μgZn/l, 0.003-0.038 μgCd/l, 0.28-6.29 μgPb/I. Labile complexes in these waters constituted: 3.8-24.1% for Zn, 25.9-35.8% for Cd and 24.3-57.8% for Pb of the total metal concentration. Copper concentration in studied melioration ditch amounted to 24.4 μg/l. The ionic and colloidal forms constituted 39.1% and 24.8% of its total concentration, respectively.
11

Analiza wspolzaleznosci pomiedzy metalami w krwawniku pospolitym [Achillea millefolium L.] a ich zawartoscia w glebie

59%
Kwapulinski J., Paukszto A., Rochel R., Rzepka J., Ahnert B., Bogunia M., Linkarczyk G., Labedzka J.
Bromatologia i Chemia Toksykologiczna
|
2005
|
tom 38
|
nr Supl.
309-313
Wzajemne interakcje pomiędzy Pb, Cd, Mn, Ni, Fe, Cr, Cu i Zn przedstawiono za pomocą stosunku ich zawartości w czterech częściach morfologicznych krwawnika pospolitego (Achillea millefolium L.) w odniesieniu do ich chemicznych form występowania w glebie. Badania przeprowadzono na terenach przemysłowych (Mysłowice) oraz rekreacyjnych (Niżna Łąka, Sierpc i Czernie).
12
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Przydatnosc metody BCR do oceny mobilnosci cynku w osadzie sciekowym kompostowanym roznymi metodami. Cz. II

51%
Patorczyk-Pytlik B.
Zeszyty Problemowe Postępów Nauk Rolniczych
|
2006
|
tom 512
|
nr 2
457-464
W przeprowadzonym doświadczeniu wazonowym oceniono zależności pomiędzy formą chemiczną Zn wprowadzonego do gleby wraz z kompostowanym czterema metodami osadem ściekowym a zawartością tego metalu w uprawianej kukurydzy. Komposty z: samego osadu, osadu z dodatkiem węgla brunatnego, wermikompost z osadu oraz z osadu z dodatkiem węgla zastosowanego w dawkach odpowiadających 5 i 10% masy gleby. Chemiczną specjację cynku przeprowadzono metodą BCR. Stwierdzono, że zawartość cynku w roślinach była istotnie dodatnio skorelowana z całkowitą i rozpuszczalną w mol HCl·dm³ zawartością Zn oraz ilością tego metalu występującego w glebach we frakcji FI, F2 i F3.
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