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1.
M. F. Frontasyeva S. S. Pavlov N. G. Aksenova L. M. Mosulishvili A. I. Belokobylskii E. I. Kirkesali E. N. Ginturi N. E. Kuchava 《Journal of Analytical Chemistry》2009,64(7):746-749
The interaction of different chromium species with blue-green microalga Spirulina platensis was studied by neutron activation analysis (NAA). It was found that, in contrast to other microorganisms, spirulina predominantly assimilates nontoxic, essential Cr(III) species rather than the toxic Cr(VI) species. Photometry and EPR proved the absence of toxic chromium species with high degrees of oxidation in the course of Cr(III) accumulation by S. platensis cells. The relationship between the Cr(III) concentration in the chromium-containing spirulina biomass and the chromium concentration in the nutrient medium was found; it can be used for the determination of Cr(III) concentrations necessary for cell cultivation. The control of the protein composition and cytological status of cells showed that the S. platensis biomass assimilated Cr(III) in necessary concentrations under the selected conditions retained its protein composition and useful natural properties, and, hence, could be used for medical and preventive purposes. 相似文献
2.
L. M. Mosulishvili Ye. I. Kirkesali A. I. Belokobylsky A. I. Khizanishvili M. V. Frontasyeva S. F. Gundorina C. D. Oprea 《Journal of Radioanalytical and Nuclear Chemistry》2002,252(1):15-20
To evaluate the potentiality of the blue-green algae Spirulina platensis as a matrix for the production of Se-containing pharmaceuticals, the background levels of 31 major, minor and trace elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni using (n,p) reaction), As, Br, Zn, Rb, Mo, Ag, Sb, I, Ba, Sm, Tb, Tm, Hf, Ta, W, Au, Hg, Th were determined in Spirulina platensis biomass by means of epithermal neutron activation analysis. The possibility of the purpose-oriented incorporation of Se into Spirulina platensis biomass was demonstrated. The polynomial dependence of the Se accumulation on nutritional medium loading was revealed. The analytical technique used allows to control the amount of toxic elements in algae Spirulina platensis. Based on this study, a conclusion of the possibility to use Spirulina platensisas a matrix for the production of Se-containing pharmaceutical was drawn. 相似文献
3.
O. Navrátil Z. Kobliha E. Halámek Z. Skaličan 《Journal of Radioanalytical and Nuclear Chemistry》2002,252(1):31-35
To evaluate the potentiality of the blue-green algae Spirulina platensis as a matrix for the production of Se-containing pharmaceuticals, the background levels of 31 major, minor and trace elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni using (n,p) reaction), As, Br, Zn, Rb, Mo, Ag, Sb, I, Ba, Sm, Tb, Tm, Hf, Ta, W, Au, Hg, Th were determined in Spirulina platensis biomass by means of epithermal neutron activation analysis. The possibility of the purpose-oriented incorporation of Se into Spirulina platensis biomass was demonstrated. The polynomial dependence of the Se accumulation on nutritional medium loading was revealed. The analytical technique used allows to control the amount of toxic elements in algae Spirulina platensis. Based on this study, a conclusion of the possibility to use Spirulina platensisas a matrix for the production of Se-containing pharmaceutical was drawn. 相似文献
4.
Marina Frontasyeva Elena Kirkesali 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(2):421-426
Some results from applying epithermal neutron activation analysis at FLNP JINR, Dubna, Russia, in medical biotechnology, environmental
biotechnology and industrial biotechnology are reviewed. In the biomedical experiments biomass from the blue-green alga Spirulina platensis (S. platensis) has been used as a matrix for the development of pharmaceutical substances containing such essential trace elements as selenium,
chromium and iodine. The feasibility of target-oriented introduction of these elements into S. platensis biocomplexes retaining its protein composition and natural beneficial properties was shown. The absorption of mercury on
growth dynamics of S. platensis and other bacterial strains was observed. Detoxification of Cr and Hg by Arthrobacter globiformis 151B was demonstrated. Microbial synthesis of technologically important silver nanoparticles by the novel actinomycete strain
Streptomyces glaucus 71 MD and blue-green alga S. platensis were characterized by a combined use of transmission electron microscopy, scanning electron microscopy and energy-dispersive
analysis of X-rays. It was established that the tested actinomycete S. glaucus 71 MD produces silver nanoparticles extracellularly when acted upon by the silver nitrate solution, which offers a great
advantage over an intracellular process of synthesis from the point of view of applications. The synthesis of silver nanoparticles
by S. platensis proceeded differently under the short-term and long-term silver action. 相似文献
5.
S. V. Pervushkin A. V. Voronin V. A. Kurkin A. A. Sokhina I. F. Shatalaev 《Chemistry of Natural Compounds》2001,37(5):476-481
The accumulation dynamics of total protein, its fractional composition, and the molecular forms of key oxidoreductases were studied during cultivation ofSpirulina platensisbiomass. 相似文献
6.
Canan Höçük Özkan Mehmet Atakay Bekir Salih Gülay Ertaş 《Journal of mass spectrometry : JMS》2024,59(5):e5020
Exposure to arsenic can cause various biological effects by increasing the production of reactive oxygen species (ROS). Selenium acts as a beneficial element by regulating ROS and limiting heavy metal uptake and translocation. There are studies on the interactive effects of As and Se in plants, but the antagonistic and synergistic effects of these elements based on their binding to glutathione (GSH) molecules have not been studied yet. In this study, we aimed to investigate the antagonistic or synergistic effects of As and Se on the binding mechanism of Se and As with GSH at pH 3.0, 5.0, or 6.5. The interaction of As and Se in Se(SG)2 + As(III) or As(SG)3 + Se(IV) binary systems and As(III) + Se(IV) + GSH ternary system were examined depending on their ratios via liquid chromatography diode array detector/electrospray mass spectrometry (LC-DAD/MS) and liquid chromatography–electrospray ionization–tandem mass spectrometry (LC-ESI-MS/MS). The results showed that the formation of As(GS)3 was not detected in the As(III) + Se(SG)2 binary system, indicating that As(III) did not affect the stability of Se(SG)2 complex antagonistically. However, in the Se(IV) + As(SG)3 binary system, the addition of Se(IV) to As(SG)3 affected the stability of As(SG)3 antagonistically. Se(IV) reacted with GSH, disrupting the As(SG)3 complex, and consequently, Se(SG)2 formation was measured using LC-MS/DAD. In the Se(IV) + GSH + As(III) ternary system, Se(SG)2 formation was detected upon mixing As(III), Se(IV), and GSH. The increase in the concentration of As(III) did not influence the stability of the Se(SG)2 complex. Additionally, Se(IV) has a higher affinity than As(III) to the GSH, regardless of the pH of the solution. In both binary and ternary systems, the formation of the by-product glutathione trisulfide (GSSSG) was detected using LC-ESI-MS/MS. 相似文献
7.
Keliang Shi Fuqiang Liu Yuanlv Ye Zhijun Guo Wangsuo Wu 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(3):1277-1283
Metal ions sorption can be significantly affected by the presence of other sorbates, especially of complexing ligands. In
this study, the effect of Se(IV) on Eu(III) sorption onto TiO2 at different pH and Eu(III) concentration was investigated. Se(IV) was found to enhance Eu(III) sorption as a function of
Se(IV) concentration. Constant capacitance model was successfully used to interpret the sorption experimental data. The solubility
product of Eu2(SeO3)3 at ambient temperature was investigated to highlight the sorption mechanism of ternary sorption system. The pK
sp value of Eu2(SeO3)3 was found to be 31.51 ± 0.95. 相似文献
8.
Zusammenfassung Titan(III)chlorid, Titan (IV)oxyperchlorat, Vanadin(III)chlorid, Vanadin(IV)oxyperchlorat, Chrom(III)chlorid und Chrom(III)perchlorat wurden in 1,2-Propandiolcarbonat polarographisch untersucht; die Art der Grenzströme, die Diffusionsstromkonstanten, die Diffusionskoeffizienten, die Art der Abscheidungsvorgänge und die Lage der Halbwellenpotentiale, bez. auf die gesätt. wäßr. Kalomelelektrode, wurden bei 25° in 0,1M-Lösungen von Tetraäthylammoniumperchlorat bestimmt. Es wurden die Reduktionsvorgänge Ti(IV)–Ti(III), V(III)–V(II), V(IV)–V(II), Cr(III)–Cr(II) und Cr(II)–Cr(0) aufgefunden, wobei nur V(III)–V(II) reversibel verläuft.
Mit 2 Abbildungen
1. Mitt.:V. Gutmann, M. Kogelnig undM. Michlmayr, Mh. Chem.99, 693 (1968).
2. Mitt.:V. Gutmann, M. Kogelnig undM. Michlmayr, Mh. Chem.99, 699 (1968). 相似文献
Polarographic investigation have been carried out on titanium(III)chloride, titanium(IV)oxoperchlorate, vanadium(III)chloride, vanadium(IV)oxoperchlorate, chromium(III)chloride and chromium(III)perchlorate in 1,2-propanediol-carbonate; the nature of the limiting currents, the diffusion current constants, the diffusion coefficients, the reversibility or irreversibility of the electrode process and the half-wave potentials vs. aqueous saturated calomel electrode have been determined in 0,1M solutions of tetraethylammonium perchlorate at 25°. Reduction waves were found corresponding to Ti(IV)–Ti(III), V(III)–V(II), V(IV)–V(II), Cr(III)–Cr(II) and Cr(II)–Cr(0)
Mit 2 Abbildungen
1. Mitt.:V. Gutmann, M. Kogelnig undM. Michlmayr, Mh. Chem.99, 693 (1968).
2. Mitt.:V. Gutmann, M. Kogelnig undM. Michlmayr, Mh. Chem.99, 699 (1968). 相似文献
9.
Mix cultivation of microalgae (Spirulina platensis) and yeast (Rhodotorula glutinis) for lipid production was studied. Mixing cultivation of the two microorganisms significantly increased the accumulation
of total biomass and total lipid yield. Dissolved oxygen and medium components in the mixed fermentation medium were analyzed.
Mix cultivation in monosodium glutamate wastewater was further studied. Result indicated 1,600 mg/L of biomass was obtained
and 73% of COD were removed. 相似文献
10.
Serezhkin V. N. Serezhkina L. B. Shishkina O. V. Pushkin D. V. 《Russian Journal of Coordination Chemistry》2003,29(3):203-218
Using the Voronoi–Dirichlet partition procedure and the method of intersecting spheres, it is demonstrated that in the crystal structures of chalcogen-containing compounds, Pt(IV) atoms form only PtX6 octahedra (X = S, Se, Te), whereas in the case of Pt(III) and Pt(II), square coordination by X atoms is typical. The Pt(II) atoms can also form PtX5 square pyramids (X = S, Se), PtS6 octahedra, and PtTe3Pt3 quasi-octahedra in which a platinum atom is located in the trans-position to each coordinated tellurium atom. It was found that Pt(II) atoms in the PtX4 squares (X = S, Se), unlike square-coordinated Pt(III) atoms, can form one or two Pt–M bonds (M is a d metal) and 1 to 4 secondary Pt–Q bonds, where Q is an s metal or hydrogen. The main features of platinum stereochemistry depending on the metal valence state and coordination number (CN) and on the nature of the chalcogen atom were quantitatively characterized in terms of the Voronoi–Dirichlet polyhedra. 相似文献
11.
Abuzer Çelekli Ali Topyürek Giorgos Markou Hüseyin Bozkurt 《Applied biochemistry and biotechnology》2016,180(4):728-739
The study was performed to investigate the effects of using cow effluent for the cultivation of Spirulina platensis on its biomass production and cell physiology. S. platensis was cultivated in three different cow effluents (CE) used as cultivation medium during 15 days. CE was prepared using dry cow manures, and it was further modified with supplement of NaNO3 (CEN) and NaNO3 + NaCl (CENS). High nitrate value stimulated chlorophyll-a and total protein content of the cyanobacterium and also biomass production in standards medium (SM) and CEN media. Total carbohydrate content of S. platensis grown in CE media was found to be higher (p < 0.05) than that of SM. Productions of biomass and biochemical compounds by the cyanobacterium grown on the CE and SM media were evaluated by using multivariate approach. Conductivity, oxidation reduction potential (ORP), salinity, pH, and TDS played important role (p < 0.01) in the biochemical composition. As an effective explanatory factor, ORP had a significant positive correlation with H2O2, whereas negatively correlated with chlorophyll-α, biomass production, filament length, and proline. Canonical correspondence analysis proposed that biochemical compounds of S. platensis were not only affected by salinity and nutrition of media but also by pH and ORP. The present study indicated that CEN as a low cost model medium had high potential for the production of biomass by S. platensis with high protein content. 相似文献
12.
Kinetics and mechanism of the cerium(IV) oxidation of Cr(III) complexes of a series of macrocyclic (or pseudomacrocyclic) ligands with [14]-membered intraligand ring-sizes have now been investigated at I = 1.0 M (LiClO4) Temp. 30°C. The complexes of the formulation Cr(macrocycle)(X)(H2O) where X = CHCl2 and H2O, n = 0 or 1 undergo oxidation to Cr(VI) with the formation of chromium(IV) intermediates. The observed kinetic parameters for the Ce(IV) oxidation of Cr(III) macrocyclic complexes have been discussed in terms of changes brought about by the macrocyclic ligands on the Cr(III)—Cr(IV) redox potentials and in specific rates for Cr(IV)—Cr(V) conversion. On the basis of this study, it has been suggested that the trapping of Cr(IV) is easier when a macrocyclic ligand having a symmetrical intra-ligand ring size and unsaturation in the cyclic structure is coordinated equatorially. Cyclic voltammetric studies indicate the formation of Cr(IV) transient in the case of electrochemical oxidation of trans-Cr(Me4[14]tetraene)(H2O). 相似文献
13.
The synthesis of a new Schiff base derived from 2-hydroxy-5-chloroacetophenone and 4-amino-5-mercapto-3-methyl-1,2,4-triazole
and its coordination compounds with Ti(III), VO(IV), Cr(III), Mn(III), Fe(III), Zr(IV), MoO2(VI), and UO2(VI) are described. The ligand and the complexes have been characterized on the basis of analytical, electrical conductance,
molecular weight, IR and electronic spectra, magnetic susceptibility measurements, and thermogravimetric analysis. The ligand
acts as a dibasic tridentate molecule. Antibacterial activities of the ligand and its metal complexes have been determined
by screening the compounds against E. coli, S. typhi, P. aeruginosa, and S. aureus. The solid state de electrical conductivity of the ligand and its complexes have been measured over 313–403 K, and the complexes
were found to be of semiconducting nature.
The article was submitted by the authors in English. 相似文献
14.
Absorption spectra, emission spectra, and magnetic susceptibility from 4.2 to 300°K have been measured for β-alumina doped with chromium. Chromium-doped β-alumina sintered in air was found to contain only Cr(IV) even though Cr(III) was the oxidation state initially present. Heating air-sintered samples at 1200°C in for 5 hr reduced the Cr(IV) to Cr(III). The absorption spectra for Cr(IV) and Cr(III) have been fitted to the Tanabe-Sugano diagram and Dq and B were calculated. Results are consistent with the assignment of both Cr(III) and Cr(IV) to octahedral coordination sites in β-alumina. A parallel study of chromium doped α-alumina also showed the existence of Cr(IV) and Cr(III) in that host lattice depending on the firing atmosphere. 相似文献
15.
Oximidobenzotetronic acid is recommended for the separation and gravimetric determination of palladium and cobalt An ethanolic solution of the reagent quantitatively precipitates palladium(II) from solutions which are 0.75 N in acid up to pH 5.1, the complex is weighed as Pd(C9H5NO4)2. Cobalt(II) can be determined in the filtrate after the precipitation of palladium. With 0.5 N acid solutions, no interference was found from Pt(IV), Ir(IV), Rh(III), Ru(III), Os(IV), Au(III), Ag(I), Cu(II), Fe(III), Ni(II), Hg(II). Pb(II), Bi(III), Cd(II), As(V), Se(VI), Te(IV), Mo(VI), Sb(III), Al(III), Cr(III), Zn(II), Ti(IV), Zr(IV). acetate, oxalate, citrate, tartrate, phosphate and fluoride. 相似文献
16.
The present study is performed to examine the accumulation efficiency of 51Cr(III) and 51Cr(VI) by the alkaloid piperine, derived from the fruits of Piper nigrum (Family Piperaceae) as well as using the fruit commonly known as black pepper by radiometric technique. The pH dependence
and the effect of the concentration of chromium on the accumulation have also been examined. The maximum accumulation (52%)
of Cr(III) is found by black pepper at pH 4 whereas piperine shows slight accumulation at this condition. Accumulation of
Cr(VI) by black pepper is always negligible. It has also been observed that some other constituents of the black pepper like
gum, terpenoid, etc., besides piperine is responsible for the accumulation of chromium. 相似文献
17.
M N Matos Reyes M L Cervera M de la Guardia 《Analytical and bioanalytical chemistry》2009,394(6):1557-1562
A sensitive and simple analytical method has been developed for determination of Sb(III), Sb(V), Se(IV), Se(VI), Te(IV), Te(VI),
and Bi(III) in garlic samples by using hydride-generation–atomic-fluorescence spectrometry (HG–AFS). The method is based on
a single extraction of the inorganic species by sonication at room temperature with 1 mol L−1 H2SO4 and washing of the solid phase with 0.1% (w/v) EDTA, followed by measurement of the corresponding hydrides generated under two different experimental conditions directly
and after a pre-reduction step. The limit of detection of the method was 0.7 ng g−1 for Sb(III), 1.0 ng g−1 for Sb(V), 1.3 ng g−1 for Se(IV), 1.0 ng g−1 for Se(VI), 1.1 ng g−1 for Te(IV), 0.5 ng g−1 for Te(VI), and 0.9 ng g−1 for Bi(III), in all cases expressed in terms of sample dry weight. 相似文献
18.
The paper presents a procedure for the multi-element inorganic speciation of As(III, V), Se(IV, VI) and Sb(III, V) in natural water with GF-AAS using solid phase extraction technology. Total As(III, V), Se(IV, VI) and Sb(III, V) were determined according to the following procedure: titanium dioxide (TiO2) was used to adsorb inorganic species of As, Se and Sb in sample solution; after filtration, the solid phase was prepared to be slurry for determination. For As(III), Se(IV) and Sb(III), their inorganic species were coprecipitated with Pb-PDC, dissolved in dilute nitric acid, and then determined. The concentrations of As(V), Se(VI) and Sb(V) can be calculated by the difference of the concentrations obtained by the above determinations. For the determination of As(III), Se(IV) and Sb(III), palladium was chosen as a modifier and pyrolysis temperature was 800 °C. Optimum conditions for the coprecipitation were listed for 100 ml of sample solution: pH 3.0, 15 min of stirring time, 40.0 μg l−1 Pb(NO3)2 and 150.0 μg l−1 APDC. The proposed method was applied to the determination of trace amounts of As(III, V), Se(IV, VI) and Sb(III, V) in river water and seawater. 相似文献
19.
Biphasic Oxidation of cis‐Diaquabis(1,10‐phenanthroline)chromium(III) by N‐Bromosuccinimide and the Formation of Chromium(IV) and Chromium(V)
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The oxidation of cis‐diaquabis(1,10‐phenanthroline)chromium(III) [cis‐CrIII(phen)2(H2O)2]3+ by ‐bromosuccinimide (NBS) to yield cis‐dioxobis(1,10‐phenanthroline)chromium(V) has been studied spectrophotometrically in the pH 1.57–3.56 and 5.68–6.68 ranges at 25.0°C. The reaction displayed biphasic kinetics at pH < 4.0 and a simple first order at the pH > 5.0. In the low pH range, the reaction proceeds by two successive steps; the first faster step corresponds to the oxidation of Cr(III) to Cr(IV), and the second slower one corresponds to the oxidation of Cr(IV) to Cr(V), the final product of the reaction. The formation of both Cr(IV) and Cr(V) has been detected by electron spin resonance (ESR). The ESR clearly showed the formation and decay of Cr(IV) as well as the formation of Cr(V). Each oxidation process exhibited a first‐order dependence on the initial [Cr(III)]. The pseudo–first‐order rate constants k34 and k45, for the faster and slower steps, respectively, were obtained by a computer program using Origin7.0. Both rate constants showed first‐order dependence on [NBS] and increased with increasing pH. 相似文献
20.
The kinetics of oxidation of diaquadichloro(1,10-phenanthroline)chromium(III) complex, [CrIII(phen)(H2O)2Cl2]+, by N-bromosuccinimide (NBS) is biphasic. The first faster step involves the oxidation of Cr(III) to Cr(IV). The second slower step is due to the oxidation of Cr(IV) to Cr(V). The reaction product is isolated and characterized by electron spin resonance (ESR), IR, and elemental analysis. The chromium(V) product is consistent with the formula [CrV(phen)Cl2(O)]Br. The rate constants kf and ks, for the faster and the slower steps respectively, were obtained using an Origin 9.0 software program. Values of both kf and ks, varied linearly with [NBS] at constant reaction conditions. The effect of pH on the reaction rate is investigated over the pH (4.11–6.01) range at 25.0°C. The rate constants kf and ks increased with increasing pH. This is consistent with hydroxo forms of the chromium species being more reactive than the aqua forms. Chromium(III) complexes, more often than not, are inert. The oxidation of the Cr(III) complex to Cr(IV), most likely, proceeds by an outer sphere mechanism. Since chromium(IV) is labile the mechanism of its oxidation to chromium(V) is not certain. 相似文献