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151.
152.
153.
Magdalena Rakicka Zbigniew Lazar Anita Rywińska Waldemar Rymowicz 《Chemical Papers》2016,70(11):1452-1459
Inulin and glycerol were used as substrates for efficient erythritol and citric acid production by newly engineered Yarrowia lipolytica strains. Hydrolysis of inulin by the Y. lipolytica Wratislavia K1 strain was established by expressing the Kluyveromyces marxianus INU1 gene. Erythritol was produced in two stages: inulin was used for biomass formation, followed by erythritol biosynthesis initiated by glycerol addition. The highest titer of erythritol obtained, 120.9 g L?1 with the yield of 0.6 g g?1, was produced by the K1 INU 6 strain. Moreover, the K1 INU 6 strain in fed-batch culture produced a high amount of citric acid: 105.2 g L?1 after 235 h from 200 g L?1 of inulin. Maximum activity of inulinase during this culture was 14000 U g?1 of cell dry mass. The presented study proves the potential of new Y. lipolytica transformants for efficient erythritol and citric acid production from inexpensive raw materials such as inulin and glycerol. 相似文献
154.
Mihaela Badea Ioana Dorina Vlaicu Rodica Olar Madalina Constand Coralia Bleotu Mariana Carmen Chifiriuc Luminita Marutescu Veronica Lazar Maria Nicoleta Grecu Dana Marinescu 《Journal of Thermal Analysis and Calorimetry》2014,118(2):1119-1133
Four coordination compounds of copper(II) were synthesised and characterised in solid state by elemental analysis, infrared, electronic and EPR spectroscopy, as well as by thermal analysis (TG/DTA). The complexes were formulated on the basis of experimental data as: [Cu(BzIm)2(H2O)]·H2O (1), [Cu2(Acr)4(HBzIm)2] (2), [Cu(Acr)2(HBzIm)2] (3) and [Cu(Acr)2(HBzIm)2(H2O)]·H2O (4). IR data are in accordance with the unidentate nature of benzimidazole, in complexes (2), (3) and (4), and bridge bidentate nature of benzimidazole, in complex (1), while acrylato acts as uni- or bridge/chelate ligand. The electronic spectra display the characteristic pattern of square planar, square pyramidal, or octahedral stereochemistry, also confirmed by EPR spectra. Thermal decomposition evidenced several well-defined steps as dehydration of complexes (1) and (4), benzimidazole molecule releases for all complexes and acrylate decomposition in carbonate for complexes (3) and (4). In all four cases, the final residue after thermal treatment in air flow is copper(II) oxide, formed during the decomposition steps for complexes (3) and (4), and, respectively, after the oxidation of the metallic copper for complexes (1) and (2). Antimicrobial activities of the complexes have been determined by in vitro assays, against various Gram-negative and Gram-positive bacterial and fungal strains. Copper(II) complexes were also evaluated for their cytotoxicity on eukaryotic cells. 相似文献
155.
Rodica Olar Florentina Pătraşcu Mariana Carmen Chifiriuc Emilia Elena Iorgulescu Coralia Bleotu Luminiţa Măruţescu Veronica Lazar Dana Marinescu Nicolae Stanică Mihaela Badea 《Journal of Thermal Analysis and Calorimetry》2014,118(2):1159-1168
New species of type [MLCl2]·nH2O (M:Ni, n = 0; M:Cu, n = 1 and M:Zn, n = 0; L: 1,3,5,8,11-pentaazacyclotridecane-3-yl-(pyrid-3-yl)-methanone resulted by N,N’-bis(2-aminoethyl)ethane-1,2-diamine, nicotinamide and formaldehyde) were synthesised by one-pot condensation. Chemical analysis, ESI–MS, IR, 1H NMR, 13C NMR, UV–Vis–NIR, EPR spectroscopy as well as magnetic data at room temperature were used in order to characterise the compounds. The data provided by IR, ESI–MS and NMR spectra are consistent with the macrocycle formation. Electronic spectra indicate that both Ni(II) and Cu(II) adopt an octahedral stereochemistry data furthermore confirmed by magnetic moments and EPR spectrum at room temperature. The electrochemical behaviour of the compounds was investigated by cyclic voltammetry. Processes as water and chloride elimination as well as oxidative degradation of the macrocyclic ligand were observed by simultaneously TG–DTA measurements. The final residue as the most stable metallic oxide was identified by X-ray powder diffraction. The compound [CuLCl2]·H2O (2) exhibits fungicidal and anti-biofilm activity on Candida albicans strains. The complexes exhibit a low cytotoxicity on HEp 2 cells, except for Cu(II) species that induce the cellular cycle arrest in the G2/M phase. 相似文献
156.
Z. Djarmati R. M. Jankov J. Csanadi A. Djordjević B. Ribar D. Lazar P. Engel 《Journal of chemical crystallography》1992,22(5):585-590
The title compound 2H-10,4a-(epoxy-methano)-phenantren-12-one-l,3,4,9,10,10a-hexahydro-6-hydroxy-5-methoxy-9-keto-1,1-dimethyl-7-(1-methylethyl) isolated fromSalvia officinalis L. have been investigated by nuclear magnetic resonance (NMR) spectroscopy and X-ray analysis. Investigation of1H and13C NMR, homonuclear (COSY) (1H-1H) and heteronuclear (1H-13C) spectra, permitted the unambiguous assignment of the1H and13C spectra, what gave the possibility to resolve the signals of similar natural products. Crystal data are: C21H26O5,M
r=358.43, orthorhombic,P21,21,21, (No. 19),a=10.671(2),b=11.976(3),c=14.601(5)Å,V=1865.9(9)Å3,Z=4,D
x=1.276 mg–3, (MoK)=0.7107 Å,=0.84 cm–1, F(000)=768,T=293(1) K. The structure was solved by direct methods and refined toR=0.041 for 1832 observed reflections collected on CAD-4 diffractometer. 相似文献
157.
158.
H. Weiss B. J. Mair B. H. Moerbeck A. C. van Beest A. Lazar K. Weisselberg und W. L. Horner 《Fresenius' Journal of Analytical Chemistry》1936,106(4-6):232-234
Ohne Zusammenfassung 相似文献
159.
The application of subtractive mode differential pulse anodic stripping voltammetry (SDPASV) at a stationary mercury-coated glassy carbon electrode for the analysis of labile Zn(II), Cd(II), Pb(II) and Cu(II) is described. It is shown that the method has an improved sensitivity to Cu(II) owing to elimination of high background currents normally encountered in normal mode DPASV at the TFME. The sensitivity limits of the present method to Cd(II) and Cu(II) is estimated to be 0.025 and 0.067 ppb respectively, when a 2 min deposition time is used. It is suggested that the high sensitivity of the method coupled to the relative simplicity of the stationary electrodes could make the method useful in environmental and natural water studies. 相似文献
160.
Lazar Balint Irena Vedrina-Dragojević Blaženka Šebečić Jelena Momirović-Čuljat Marija Horvatić 《Mikrochimica acta》1997,127(1-2):61-65
A highly selective spectrofluorometric method for the determination of total mercury (Hg) in waste waters is described. Fluorescence quenching of rhodamine B with Hg(II) in the presence of iodide, after a concentration step, is the basis of this sensitive method. All forms of mercury, including organic compounds, are pre-oxidized to ionic mercury by acidic potassium permanganate. The final and complete oxidation is achieved by adding potassium persulphate and heating. Hg(II) was reduced by tin(II) chloride and Hg vapour driven by an air stream into an absorption solution containing potassium permanganate and sulphuric acid, using a closed, recirculating air stream. In this solution fluorescence quenching of rhodamine B at an excitation wavelength of 485 nm and emission wavelength of 586 nm was measured. The recoveries were done by adding 3.0 g Hg/100 ml to each sample before the digestion. It was indicated that the recoveries for determining mercury in waste waters were 98.3%–102.7%. The method gives reliable results down to a concentration of 10 ng Hg/ml waste water. 相似文献