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1

Microbiological oxidation of the waste ferrous sulphate

100%
Nowaczyk K., Juszczak A., Domka F.
Polish Journal of Environmental Studies
|
1999
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tom 08
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nr 6
The ferrous sulphate, which is a waste product in titanium white production at the Chemical Plant "Police" S.A., was subjected to microbiological oxidation with Thiobacillus ferrooxidans bacteria. The kinetic parameters of the culture growth were calculated on the basis of the Monod equation. The process was found to be best described by the model of the autocatalytic 1st order reaction with respect to the product and 1st order reaction with respect to the substrate. The effect of temperature and pH on the course of the process was studied. The kinetics of oxidation of ferrous ions coming from the waste ferrous sulphate was studied in the process with laboratory bacteria strain as well as the strain adapted to the waste product and compared with that of pure substrate oxidation. Analysis of the precipitates formed during microbiological oxidation of the waste ferrous sulphate proved that (NH4)Fe3(SO4)2(OH)6 with the admixture of NaFe3(SO4)2(OH)6 and KFe3(SO4)2(OH)6 are formed.
2
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The influence of black currant [Ribes nigrum] seed extract on effectiveness of human ceruloplasmin in Fe[II] ions elimination

84%
Budzyn M., Iskra M., Wielkoszynski T., Malecka M., Gryszczynska B.
Journal of Elementology
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2009
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tom 14
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nr 2
217-227
Ions of irons, especially ferrous ions may be harmful for living organisms, because they generate reactive oxygen species like O2 •- or •OH. Probability of the risk rises especially in pathological conditions, in which high level of iron is observed. For this reason scientists try to establish new methods that can support organism in eliminating reactive ferrous ions. Nowadays, attention focuses on substances present in plants, especially polyphenols, whose administration prevents oxidative damages in iron overloading. This new approach requires some research on behavior of plant-derived compounds in human organism, within a system containing other biomolecules involved in iron metabolism. The aim of this study has been to investigate the influence of black currant (Ribes nigrum) seed extract, a source of polyphenols, on the activity of ceruloplasmin, an enzyme participating in Fe(II) elimination from blood plasma in human organism. Depletion of Fe(II) caused by ceruloplasmin isolated from healthy blood donors was compared to its decrease in a system containing both ceruloplasmin and the extract. The results have shown that addition of a particular amount of the extract elevates the effectiveness of ceruloplasmin in eliminating Fe(II) from the sample but only under physiological condition (pH 7.4; T 37°C). In a weak acidic solution, addition of the extract does not lead to any change in Fe(II) concentration.
3
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Changes in the sorption of manganese and iron ions under the effect of differentiated oxygenation and reaction of the soil

84%
Jackowska I., Gaszczyk R.
Zeszyty Problemowe Postępów Nauk Rolniczych
|
1993
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tom 400
The study is concerned with the course of sorption of Fe²⁺, Fe³⁺ and Mn²⁺ ions and with their washing, out with distilled water in sandy, loess, and loamy soils. Sorption was conducted according to the idynamic method. ODR and Eh were measured as indices of soil oxygenation. It was found that oxygen deficiency of the soils under study, with a change in their reaction from acid to neutral, resulted in: 1. an increase in the sorption of Fe²⁺ and Fe³⁺ ions, 2. an increase in the sorption of Mn²⁺ ions in the loamy soil only.
4

The effect of copper, zinc and iron ions on induction of the reactive oxygen species production in tobacco by-2 cell suspension culture

84%
Zrobek-Sokolnik A., Gorecki R. J.
Polish Journal of Natural Sciences. Supplement
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2003
|
tom 01
5

Generation of OH initiated by interaction of Fe2plus and Cuplus with dioxygen; comparison with the Fenton chemistry

84%
Urbanski N. K., Beresewicz A.
Acta Biochimica Polonica
|
2000
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tom 47
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nr 4
Iron and copper toxicity has been presumed to involve the formation of hydroxyl radical (.OH) from H2O2 in the Fenton reaction. The aim of this study was to verify that Fe2+-O2 and Cu+-O2 chemistry is capable of generating .OH in the quasi physiological environment of Krebs-Henseleit buffer (KH), and to compare the ability of the Fe2+-O2 system and of the Fenton system (Fe2+ + H2O2) to produce .OH. The addition of Fe2+ and Cu+ (0-20 µM) to KH resulted in a concentration-dependent increase in .OH formation, as measured by the salicylate method. While Fe3+ and Cu2+ (0-20 µM) did not result in .OH formation, these ions mediated significant .OH production in the presence of a number of reducing agents. The .OH yield from the reaction mediated by Fe2+ was increased by exogenous Fe3+ and Cu2+ and was prevented by the deoxygenation of the buffer and reduced by superoxide dismutase, catalase, and desferrioxamine. Addition of 1 µM, 5 µM or 10 µM Fe2+ to a range of H2O2 concentrations (the Fenton system) resulted in a H2O2-concentration-dependent rise in .OH formation. For each Fe2+ concentration tested, the .OH yield doubled when the ratio [H2O2]:[Fe2+] was raised from zero to one. In conclusion: (i) Fe2+-O2 and Cu+-O2 chemistry is capable of promoting .OH generation in the environment of oxygenated KH, in the absence of pre-existing superoxide and/or H2O2, and possibly through a mechanism initiated by the metal autoxidation; (ii) The process is enhanced by contaminating Fe3+ and Cu2+; (iii) In the presence of reducing agents also Fe3+ and Cu2+ promote the .OH formation; (iv) Depending on the actual [H2O2]:[Fe2+] ratio, the efficiency of the Fe2+-O2 chemistry to generate .OH is greater than or, at best, equal to that of the Fe2+-driven Fenton reaction.
6
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Wpływ metali na brunatnienie roztworów glikozy z lizyną

67%
Markuze Z.
Roczniki Państwowego Zakładu Higieny
|
1963
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tom 14
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nr 1
7
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Characterization of outer membrane proteins participating in iron transport in Pasteurella multocida serotype A3

67%
Puchalski A., Dec M., Wernicki A., Urban-Chmiel R., Gieral A.
Polish Journal of Veterinary Sciences
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2010
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tom 13
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nr 1
121-127
Iron-regulated outer membrane proteins (IROMPs) of P. multocida serotype A3, which function as receptors for complexes containing iron ions, are induced by iron deficiency in the bacterial growth environment. Analysis of an electrophoresis image of proteins isolated from bacteria grown on medium supplemented with 2,2'-dipyridyl revealed expression of 16 new proteins that were not noted in the case of the bacteria grown in standard conditions, with molecular weights from 30 to 160 kDa. Induction of IROMP expression occurred within 30 minutes after restricted iron conditions were established. In immunoblotting, distinct reactions were noted for proteins of molecular weight ranges of 25-49 kDa, 61-95 kDa, and 108-214 kDa. Proteins of the molecular weight of 68, 75 and 86 kDa were analysed using mass spectrometry and matched with the highest probability to proteins in the NCBI data base. Several dozen different proteins with similar amino acid sequences were matched to each sample.
8

The influence of pH and Fe(II) ions on physicochemical properties of oxidised potato starch

67%
Pietrzyk S., Fortuna T., Ras L.
Electronic Journal of Polish Agricultural Universities. Series Food Science and Technology
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2007
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tom 10
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nr 4
9
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Oddzialywanie jonow platyny [IV] na jony zelaza [II] w glebie lessowej

67%
Bojanowska M., Jackowska I.
Acta Agrophysica
|
2003
|
tom 02
|
nr 3[97]
509-517
10

Concentrations of macroelements, zinc and iron ions in water of the Upper Narew basin, NE Poland

67%
Skorbilowicz M.
Polish Journal of Environmental Studies
|
2010
|
tom 19
|
nr 2
397-405
The purpose of present research was to evaluate the dynamics of concentration changes of macroelements as well as iron and zinc ions in the upper Narew River catchment (northeastern Poand). The following rivers and streams were selected: Narew, Supraśl, Horodnianka, Ruda, Małynka, Łoknica, and Rudnia. Calcium, magnesium, sodium, potassium, iron and zinc analyses were made using the flame AAS method. A gradual increase of macroelement contents in Narew water was found, which was the consequence of water supplies and surface runoffs. Our study revealed the differentiation of macroelements, iron and zinc concentrations in water of the upper Narew River, depending on the catchment character as well as spatial distribution of their point sources.
11

The role of labile iron pool in cardiovascular diseases

67%
Kruszewski M.
Acta Biochimica Polonica
|
2004
|
tom 51
|
nr 2
Although multiple factors are associated with cardiovascular pathology, there is now an impressive body of evidence that free radicals and nonradical oxidants might cause a number of cardiovascular dysfunctions. Both direct damage to cellular com­ponents and/or oxidation of extracellular biomolecules, e.g. LDL, might be involved in the aetiology of cardiovascular diseases. The key molecules in this process seem to be iron and copper ions that catalyse formation of the highly reactive hydroxyl radi­cal. Chelation of iron ions has a beneficial effect on the processes associated with the development of atherosclerosis and formation of post-ischemic lesions. These find­ings are indirectly supported by the increasing body of evidence that stored body iron plays a crucial role in pathogenesis of atherosclerosis and ischemia/reperfusion injury.
12

Jakosc wod powierzchniowych w gorskich mikrozlewniach rolniczo-lesnych

34%
Kanownik W., Pijanowski Z.
Acta Scientiarum Polonorum. Formatio Circumiectus
|
2002
|
tom 01
|
nr 1-2
61-70
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