Effects of non-ionic surfactants on the uptake and hydrolysis of fluoresceindiacetate by alkane-oxidizing bacteria

2000 ◽  
Vol 46 (4) ◽  
pp. 387-390 ◽  
Author(s):  
Per Bruheim ◽  
Kjell Eimhjellen
Keyword(s):  
Cell Surface ◽  
Uptake Rate ◽  
Biological Effects ◽  
Quantitative Difference ◽  
Chemical Properties ◽  
Ionic Surfactants ◽  
Physico Chemical ◽  
Hydrolysis Of

Biological effects of non-ionic surfactants on alkane-oxidizing bacteria were studied by assessing their influence on the uptake of prefluorochrome fluoresceindiacetate (FDA) and its intracellular hydrolysis to fluorescein. Both decreasing and increasing rates of hydrolysis as a consequence of the presence of surfactants were observed. The surfactants influenced the uptake of FDA, but not its intracellular hydrolysis. The effects of the surfactants on the uptake rate depended strongly on the structure and physico-chemical properties of the surfactants. There was no qualitative or significant quantitative difference in surfactant susceptibility between induced (alkane grown) and non-induced bacteria (acetate grown), even though the induced cells possess greater cell surface hydrophobicity.Key words: fluoresceindiacetate, bacteria, surfactants, alkane.

Physico-chemical properties and biological effects of diesel and biomass particles

2016 ◽  
Vol 215 ◽  
pp. 366-375 ◽  
Author(s):  
Eleonora Longhin ◽  
Maurizio Gualtieri ◽  
Laura Capasso ◽  
Rossella Bengalli ◽  
Steen Mollerup ◽  
...  
Keyword(s):  
Biological Effects ◽  
Chemical Properties ◽  
Physico Chemical ◽  
Biomass Particles

scholarly journals Tryptic phosphopeptides from whole casein. II. Physicochemical properties related to the solubilization of calcium

1989 ◽  
Vol 56 (3) ◽  
pp. 335-341 ◽  
Author(s):  
Rafael Berrocal ◽  
Serge Chanton ◽  
Marcel A. Juillerat ◽  
Blaise Favillare ◽  
Jean-Claude Scherz ◽  
...  
Keyword(s):  
Binding Sites ◽  
Calcium Phosphates ◽  
Chemical Properties ◽  
Sodium Caseinate ◽  
Ph Values ◽  
Physico Chemical ◽  
Casein Phosphopeptides ◽  
Hydrolysis Of ◽  
Phosphate Solutions ◽  
Tryptic Hydrolysis

SummaryCasein phosphopeptides (GPP) were produced by tryptic hydrolysis of sodium caseinate and further purified by precipitation and chromatography on QAE-Sephadex A-25. Their physico-chemical properties were compared with the properties of an enzymically dephosphorylated equivalent preparation (DPP). Binding of Ca2+ to the peptides was measured using a Ca selective electrode and was found to increase with pH and to show 1/1 stoicheiometry Ca/Porg in CPP at pH 6·5 a.nd 7·6. Klotz plots indicated equivalent binding sites at these two pH values, but some heterogeneity was seen at pH 3·5. In contrast, DPP did not bind significant amounts of Ca2+.CPP effectively inhibited the formation of insoluble calcium phosphates at different Ca/P ratios. The effective CPP concentration was 10 mg/1 and complete stability of calcium phosphate solutions was obtained at about 100 mg/1. This stabilizing effect was dependent on the presence of organic P.

The Effect of Calcinations Temperature on the Performance of TiO2 Aggregates-Based Dye Solar Cells (DSCs)

2011 ◽  
Vol 364 ◽  
pp. 248-253 ◽  
Author(s):  
Nur Azella Zaine Siti ◽  
Muti Mohamed Norani ◽  
Mohamad Azmi Bustam
Keyword(s):  
Conversion Efficiency ◽  
Chemical Properties ◽  
Energy Conversion Efficiency ◽  
Synthesis Process ◽  
Solar Simulator ◽  
Electron Generation ◽  
Physico Chemical ◽  
Vis Spectroscopy ◽  
Dye Solar Cells ◽  
Hydrolysis Of

Development of novel TiO2 nanostructures as the photo-electrode material is one possible solution to control the competition between electron generation and recombination which is the main constraint of obtaining higher conversion efficiency of dye solar cell (DSC). By manipulating the synthesis process, desired TiO2 nanostructure with specific properties can be obtained to enhance solar energy conversion efficiency. In this study, the effect of calcinations temperature towards physico-chemical properties of synthesized TiO2 aggregates and their influence on overall light conversion efficiency of DSC has been investigated. TiO2 aggregates (0.45 µm) composing of nanocrystallites (10-40 nm), were synthesized through hydrolysis of dilute titanium alkoxide in ethanol. The synthesized samples have been characterized using FESEM, XRD and UV-Vis spectroscopy. DSCs were then assembled and evaluated using solar simulator under 100 mW/cm2 illuminations. The size of nanocrystallites was found to increase with increasing calcinations temperature where the 500°C produced the 21 nm sized nanocrystallites, the optimum size for highest absorption of the dye resulting in the highest efficiency. TiO2 aggregates-based DSC demonstrated better performance compared to nanoparticles (P-25)-based DSC. This is attributed to the enhanced scattering introduced by micron-sized aggregates.

Biological effects and physico-chemical properties of extremely diluted aqueous solutions as a function of aging-time

2011 ◽  
Vol 5 (3-4) ◽  
pp. 117-126 ◽  
Author(s):  
Lucietta Betti ◽  
Vittorio Elia ◽  
Elena Napoli ◽  
Grazia Trebbi ◽  
Michela Zurla ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Aging Time ◽  
Biological Effects ◽  
Chemical Properties ◽  
Physico Chemical ◽  
Extremely Diluted Aqueous Solutions

scholarly journals Organosolv lignin properties and their effects on enzymatic hydrolysis

BioResources ◽  
2020 ◽  
Vol 15 (4) ◽  
pp. 8909-8924
Author(s):  
Yang Huang ◽  
Chenhuan Lai ◽  
Shaolong Sun ◽  
Qiang Yong ◽  
Brian K. Via ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Distribution Coefficient ◽  
Chemical Properties ◽  
Structural Features ◽  
Hydrolysis Yield ◽  
Pure Cellulose ◽  
Organosolv Lignin ◽  
Physico Chemical ◽  
Enzyme Distribution ◽  
Hydrolysis Of

Lignin plays a crucial role in enzymatic hydrolysis of lignocellulosic biomass. To evaluate the correlation between lignin properties and its effects on enzymatic hydrolysis, five organosolv lignins (OLs) were isolated from woody biomass, and their physico-chemical properties and structural features were characterized. The effects of OL addition on enzymatic hydrolysis of microcrystalline cellulose (pure cellulose) were assessed first, which showed their disparate effects. The addition of three OLs increased the 72 h hydrolysis yield by 7.4% to 10.1%, while the addition of other two OLs reduced the 72 h hydrolysis yield by 3.2% to 20.4%. A strong correlation between the enzyme distribution coefficient on lignins and the 72 h hydrolysis yields indicated that the enzyme-lignin interaction played a significant role in determining the lignin effects. More importantly, a correlation between lignin properties (hydrophobicity, zeta potential, and particle size) and the enzyme distribution coefficient was established. Identifying the key lignin properties will give insights to reduce the lignin inhibition by altering the lignin properties, thereby promoting enzymatic hydrolysis of lignocellulose.

Consequences of Fluoride Incorporation on Properties of Apatites

2006 ◽  
Vol 309-311 ◽  
pp. 697-700 ◽  
Author(s):  
Racquel Z. LeGeros ◽  
Dindo Q. Mijares ◽  
Fang Yao ◽  
John P. LeGeros ◽  
T. Bromage ◽  
...  
Keyword(s):  
Crystal Size ◽  
Chemical Properties ◽  
Calcium Deficiency ◽  
X Ray Diffraction ◽  
X Ray ◽  
Physico Chemical ◽  
Lower Solubility ◽  
Ft Ir ◽  
Hydrolysis Of ◽  
Ft Ir Spectroscopy

Fluoride, when incorporated in the apatite, stabilizes the structure. The purpose of this study was to determine the consequences of fluoride (F) substitution on the physico-chemical properties of apatites. F-containing apatites were prepared by precipitation or by hydrolysis of CaHPO4 in solutions containing different F concentrations and characterized using x-ray diffraction, FT-IR spectroscopy, scanning electron microscopy, thermogravimetry and chemical analyses. Results showed that F incorporation have the following effects: (a) decrease in a-axis dimension, (b) increase in crystal size and thickness, (c) decrease in calcium deficiency, and (d) lower solubility.

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