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Transition metal complexes compounds with Schiff bases ligand representing an important class of compounds that could be used to develop new metal-based anticancer agents and as precursors of metal NPs. Herein, 2,3-bis-[(3-ethoxy-2-hydroxybenzylidene)amino]but-2-enedinitrile Schiff base ligand and its corresponding copper/nickel complexes were synthesized. Also, we reported a facile and rapid method for synthesis nickel/copper nanoparticles based on thermal reduction of their complexes. Free ligand, its metal complexes and metals nanoparticles have been characterized based on elemental analysis, transmission electron microscopy, powder X-ray diffraction, magnetic measurements and by various spectroscopic (UV–vis, FT-IR, 1H NMR, GC–MS) techniques. Additionally, the in vitro cytotoxic activity of free ligand and its complexes compounds were assessed against two cancer cell lines (HeLa and MCF-7 cells)and one healthy cell line (HEK293 cell). The copper complex was found to be active against these cancer cell lines at very low LD50 than the free ligand, while nickel complex did not show any anticancer activity against these cell lines. Also, the antibacterial activity of as-prepared copper nanoparticles were screened against Escherichia coli, which demonstrated minimum inhibitory concentration and minimum bactericidal concentration values lower than those values of the commercial Cu NPs as well as the previous reported values. Moreover, the synthesized nickel nanoparticles demonstrated remarkable catalytic performance toward hydrogenation of nitrobenzene that producing clean aniline with high selectivity (98%). This reactivity could be attributed to the high degree of dispersion of Ni nanoparticles. 相似文献
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Jing Wang Hua Yang Hong Lu Jiti Zhou Jing Wang Chunli Zheng 《World journal of microbiology & biotechnology》2009,25(5):875-881
An aerobic microbial consortium constructed by the combination of Rhodotorula mucilaginosa Z1, Streptomyces albidoflavus Z2 and Micrococcus luteus Z3 was immobilized in polyurethane foam and its ability to degrade nitrobenzene was investigated. Batch experimental results
showed that polyurethane-foam-immobilized cells (PFIC) more efficiently degrade 200–400 mg l−1 nitrobenzene than freely suspended cells (FSC). Kinetics of nitrobenzene degradation by PFIC was well described by the Andrews
equation. Compared with FSC, PFIC exhibited better reusability (over 100 times) and tolerated higher shock-loadings of nitrobenzene
(1,000 mg l−1). Moreover, In the presence of salinity (≤5% NaCl, w/v), phenol (≤150 mg l−1) and aniline (≤50 mg l−1), respectively, degradation efficiency of nitrobenzene by PFIC reached over 95%. Even in the presence of both 100 mg l−1 phenol and 50 mg l−1 aniline, over 75% nitrobenzene was removed by PFIC in 36 h. Therefore, the immobilization of the defined consortium in polyurethane
foam has application potential for removing nitrobenzene in industrial wastewater treatment system. 相似文献
4.
The adsorption and primary oxidation step for the photodegradation of nitrobenzene (NB) have been studied computationally
using MSINDO SCF MO method. The method performs efficiently for extended surface models such as Ti36O90H36. Molecular dynamics simulations have revealed that NB is linked to TiO2 surface at the titanium ion via the oxygen atoms of NO2 group. In addition, the computed vibrational density of states for the adsorbed NB molecule is in reasonably good agreement
with the available experimental data and theoretical results. In order to identify the primary photochemical and photocatalytic
•OH initiated photooxidation intermediates, we have employed two different theoretical approaches, frontier orbital theory
and Wheland localization theory. It has been found that the meta- hydroxynitrocyclohexadienyl radical is energetically more favored than para- and ortho-hydroxynitrocyclohexadienyl radicals for the photochemical photolysis, whereas in the case of photocatalysis, the •OH radical attack is unselective and all three possible isomers have comparable stabilities.
Figure Minimum energy adsorption conformation of nitrobenzene onto TiO2 (100) surface 相似文献
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《Inorganica chimica acta》2002,329(1):22-30
The preparation, characterization and catalytic properties of Rh2(CO)4Cl2 immobilized on poly(4-vinylpyridine) are reported. The polymer-immobilized Rh catalyst in contact with 80% aqueous 2-ethoxyethanol is active for the water gas shift reaction and nitrobenzene reduction to azoxybenzene under carbon monoxide at 100 °C. The polymer-immobilized Rh complex was found to be reusable. The Rh complex was coordinatively bonded to the pyridine groups of the organic polymer as suggested by UV-Vis/diffuse reflectance (UV-Vis/DR), Fourier transform infrared (FT-IR), and electron paramagnetic resonance (EPR) spectroscopies. The morphology and the elemental analysis of the immobilized catalyst were studied by scanning electron microscopy-energy dispersive X-ray (SEM-EDX) technique. 相似文献
7.
Responses of a novel salt-tolerant Streptomyces
albidoflavus DUT_AHX capable of degrading nitrobenzene to salinity stress 总被引:1,自引:0,他引:1
A novel salt-tolerant strain DUT_AHX, which was capable of utilizing nitrobenzene (NB) as the sole carbon source, was isolated
from NB-contaminated soil. Furthermore, it was identified as Streptomyces albidoflavus on the basis of physiological and biochemical tests and 16S ribosomal DNA (rDNA) sequence analysis. It can grow in the presence
of NaCl up to 12% (w/v) or NB up to 900 mg/l in mineral salts basal (MSB) medium. The exogenously added osmoprotectants such
as glycin, glutamic acid, proline, betaine and ectoine can improve growth of strain DUT_AHX in the presence of 10% (w/v) NaCl.
NB-grown cells of strain DUT_AHX in modified MSB medium can degrade NB with the concomitant release of ammonia. Moreover,
crude extracts of NB-grown strain DUT_AHX mainly contained 2-aminophenol 1,6-dioxygenase activity. These indicate that NB
degradation by strain DUT_AHX might involve a partial reductive pathway. The proteins induced by salinity stress or NB were
analyzed by native-gradient polyacrylamide gel electrophoresis (PAGE) and sodium dodecyl sulfate (SDS)-PAGE. In NB-induced
proteins de novo, 141 kDa protein on the native-gradient PAGE gel was excised and electroeluted. Furthermore, enzyme tests
exhibit the 2-aminophenol 1,6-dioxygenase activity of purified 141 kDa protein is 11-fold that of the cell-free extracts.
The exploitation of strain DUT_AHX in salinity stress will be a remarkable improvement in NB bioremediation and wastewater
treatment in high salinity. 相似文献
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Nitrobenzene exposure is known to produce red blood cell damage as well as engorgement and sinusoidal congestion of the spleen in male Fischer-344 (F-344) rats but not in male B6C3F1 mice. These studies were conducted to investigate the species differences in the covalent binding of [14C]nitrobenzene in the erythrocyte and spleen and to assess the contribution of nitrobenzene-induced erythrocytic damage to the splenic effects. Total and covalently bound 14C concentrations in erythrocytes of rats were 6–13 times greater than those of mice following a single oral dose of 75, 150, 200 or 300 mg/kg [14C]nitrobenzene, suggesting that species differences in nitrobenzene-induced red blood cell toxicity may be related to differences in erythrocytic accumulation of nitrobenzene and its metabolites. Covalently bound 14C in erythrocytes of rats peaked 24 h following administration of 200 mg [14C]nitrobenzene/kg; in contrast, bound radio-label in erythrocytes from mice plateaued at 10 h. Splenic engorgement increased in a time-related manner in treated rats but not in mice. Species specificity was also observed in the accumulation of bound radiolabel in the spleen. Gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of lysed, dialyzed erythrocytes from treated rats revealed that hemoglobin was the primary, if not the exclusive, site of macromolecular covalent binding following nitrobenzene treatment. SDS-PAGE of dialyzed rat spleens revealed that 82% of total bound 14C migrated identically to hemoglobin. These data indicate that covalent binding of [14C]nitrobenzene and its metabolites in the spleen is primarily derived from bound 14C from scavenged erythrocytes. Therefore, the species differences in splenic engorgement and accumulation of [14C]nitrobenzene may be related to differences in susceptibility to nitrobenzene-induced red blood cell damage. 相似文献
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Nitrobenzene is degraded by Pseudomonas pseudoalcaligenes JS45 via 2-aminophenol to 2-aminomuconic semialdehyde, which is further degraded to pyruvate and acetaldehyde. Comamonas sp. JS765 degrades nitrobenzene via catechol to 2-hydroxymuconic semialdehyde. In this study we examined and compared the
late steps of degradation of nitrobenzene by these two microorganisms in order to reveal the biochemical relationships of
the two pathways and to provide insight for further investigation of their evolutionary history. Experiments showed that 2-hydroxymuconate,
the product of the dehydrogenation of 2-hydroxymuconic semialdehyde, was degraded to pyruvate and acetaldehyde by crude extracts
of Comamonas sp. JS765, which indicated the operation of a classical catechol meta-cleavage pathway. The semialdehyde dehydrogenases from Comamonas sp. JS765 and P. pseudoalcaligenes JS45 were able to metabolize both 2-amino- and 2-hydroxymuconic semialdehyde, with strong preference for the physiological
substrate. 2-Aminomuconate was not a substrate for 4-oxalocrotonate decarboxylase from either bacterial strain. The close
biochemical relationships among the classical catechol meta-cleavage pathway in Comamonas sp. JS765, 2-aminophenol meta-cleavage pathways in P. pseudoalcaligenes JS45, and an alternative 2-aminophenol meta-cleavage pathway in Pseudomonas sp. AP-3 suggest a common evolutionary origin.
Received: 23 November 1998 / Accepted: 3 February 1999 相似文献
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M. Auxiliadora Dea-Ayuela Encarna Castillo Marta Gonzalez-Alvarez Celeste Vega Miriam Roln Francisco Bols-Fernndez Joaquín Borrs M. Eugenia Gonzlez-Rosende 《Bioorganic & medicinal chemistry》2009,17(21):7449-7456
A series of compounds containing the nitrobenzene and sulfonamido moieties were synthesized and their leishmanicidal effect was assessed in vitro against Leishmania infantum promastigotes. Among the compounds evaluated, the p-nitrobenzenesulfonamides 4Aa and 4Ba, and the p-nitroaniline 5 showed significant activity with a good selectivity index. In a Balb/c mice model of L. Infantum, administration of compounds 4Aa, 4Ba or 5 (5 mg/kg/day for 10 days, injected ip route) led to a clear-cut parasite burden reduction (ca. 99%). In an attempt to elucidate their mechanism of action, the DNA interaction of 4Aa and 5 was investigated by means of viscosity studies, thermal denaturation and nuclease activity assay. Both compounds showed nuclease activity in the presence of copper salt. The results suggest that compounds 4Aa, 4Ba and 5 represent possible candidates for drug development in the therapeutic control of leishmaniasis. 相似文献