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1

Quaternary liquid/liquid equilibria of sodium sulfate, sodium sulfite and water with two solvents: Acetone and 2-propanol  

SciTech Connect

Aqueous solutions of sodium sulfate and sodium sulfite are produced from sodium carbonate in flue-gas scrubbers; recovery of these salts often requires multi-effect evaporators; however, a new energy-efficient unit operation called extractive crystallization has been shown to have reduced energy costs. In this process, an organic solvent is added to the aqueous salt solution to precipitate salt. Acetone is a suitable solvent for this process, better than 2-propanol. Liquid/liquid/solid equilibria for ternary systems containing a salt, water, and an organic solvent were measured. Systems investigated were sodium sulfite/water/acetone and sodium sulfite/water/2-propanol. Experiments were conducted at salt saturation covering a temperature range between the lower consolute temperature and 48.6{degrees}C. In the attempt to improve the extractive crystallization process for recovery of sodium sulfate from flue-gas scrubbers, attention was given to a feed containing a mixture of sodium sulfite and sodium sulfate. Liquid-liquid equilibria for quaternary systems containing two salts, water, and an organic solvent were experimentally determined at 35{degrees}C. The systems investigated were sodium sulfate/sodium sulfite/water/acetone and sodium sulfate/sodium sulfite/water/2propanol. The systems were studied at three salt ratios. For each salt ratio, experiments were conducted starting at saturation, water was then added until the one-phase region was reached. Mixtures of the two salts proved to have a small disadvantage relative to the 100 % sulfate feed process. Therefore, a sulfate-based extractive crystallization process is recommended.

Schiozer, A.L.

1994-03-01

2

Phylogeny of Dissimilatory Sulfite Reductases Supports an Early Origin of Sulfate Respiration  

Microsoft Academic Search

Microorganisms that use sulfate as a terminal electron acceptor for anaerobic respiration play a central role in the global sulfur cycle. Here, we report the results of comparative sequence analysis of dissimilatory sulfite reductase (DSR) genes from closely and distantly related sulfate-reducing organisms to infer the evolutionary history of DSR. A 1.9-kb DNA region encoding most of the a and

MICHAEL WAGNER; ANDREW J. ROGER; JODI L. FLAX; GREGORY A. BRUSSEAU; DAVID A. STAHL

1998-01-01

3

Biodesulfurization of flue gases and other sulfate/sulfite waste streams using immobilized mixed sulfate-reducing bacteria.  

PubMed

Sulfur dioxide (SO2) is one of the major pollutants in the atmosphere that cause acid rain. Microbial processes for reducing SO2 to hydrogen sulfide (H2S) have previously been demonstrated by utilizing mixed cultures of sulfate-reducing bacteria (SRB) with municipal sewage digest as the carbon and energy source. To maximize the productivity of the bioreactor for SO2 reduction in this study, various immobilized cell bioreactors were investigated: a stirred tank with SRB flocs and columnar reactors with cells immobilized in either potassium-carrageenan gel matrix or polymeric porous BIO-SEP beads. The maximum volumetric productivity for SO2 reduction in the continuous stirred-tank reactor (CSTR) with SRB flocs was 2.1 mmol of SO2/(h.L). The potassium-carrageenan gell matrix used for cell immobilization was not durable at feed sulfite concentrations greater than 2000 mg/L (1.7 mmol/(h.L)). A columnar reactor with mixed SRB cells that had been allowed to grow into highly stable BIO-SEP polymeric beads exhibited the highest sulfite conversion rates, in the range 16.5 mmol/(h.L) (with 100% conversion) to 20 mmol/(h.L) (with 95% conversion). The average specific activity for sulfite reduction in the column, in terms of dry weight of SRB biomass, was 9.5 mmol of sulfite/(h.g). In addition to flue gas desulfurization, potential applications of this microbial process include the treatment of sulfate/sulfite-laden wastewater from the pulp and paper, petroleum, mining, and chemical industries. PMID:9376112

Selvaraj, P T; Little, M H; Kaufman, E N

1997-01-01

4

Geochemical and cosmochemical cycles involving sulfur, sulfide, sulfite and sulfate  

Microsoft Academic Search

Raman spectra of aqueous systems containing sulfur dioxide, elemental sulfur and sulfate indicate that the equilibrium between these species is catalyzed by elemental sulfur. Therefore, dynamic equilibrium can be expected under conditions prevalent on Venus, on Io and in epigenic sulfur deposits.

B. Meyer; L. Peter; M. Ospina

1979-01-01

5

Phylogeny of Dissimilatory Sulfite Reductases Supports an Early Origin of Sulfate Respiration  

PubMed Central

Microorganisms that use sulfate as a terminal electron acceptor for anaerobic respiration play a central role in the global sulfur cycle. Here, we report the results of comparative sequence analysis of dissimilatory sulfite reductase (DSR) genes from closely and distantly related sulfate-reducing organisms to infer the evolutionary history of DSR. A 1.9-kb DNA region encoding most of the ? and ? subunits of DSR could be recovered only from organisms capable of dissimilatory sulfate reduction with a PCR primer set targeting highly conserved regions in these genes. All DNA sequences obtained were highly similar to one another (49 to 89% identity), and their inferred evolutionary relationships were nearly identical to those inferred on the basis of 16S rRNA. We conclude that the high similarity of bacterial and archaeal DSRs reflects their common origin from a conserved DSR. This ancestral DSR was either present before the split between the domains Bacteria, Archaea, and Eucarya or laterally transferred between Bacteria and Archaea soon after domain divergence. Thus, if the physiological role of the DSR was constant over time, then early ancestors of Bacteria and Archaea already possessed a key enzyme of sulfate and sulfite respiration. PMID:9603890

Wagner, Michael; Roger, Andrew J.; Flax, Jodi L.; Brusseau, Gregory A.; Stahl, David A.

1998-01-01

6

Sodium sulfite-formaldehyde pretreatment of mixed hardwoods and its effect on enzymatic hydrolysis.  

PubMed

In this work, mixed hardwoods were pretreated by sodium sulfite-formaldehyde (SF). The effects of SF pretreatment on the chemical compositions and enzymatic hydrolysis of mixed hardwoods were investigated. SF pretreatment temperature had a significant effect on pulp yield and delignification, resulting in an increased efficiency of enzymatic hydrolysis. After 96 h of enzymatic hydrolysis at the cellulase loading of 40 FPU/g substrate, the yields of glucan and xylan on the basis of original wood were 37% and 11% for the pulp produced with 12% sulfite charge at 170 °C for 2 h. The total sugar recovery based on the sugar in original wood was 74%. These results indicate that sulfite-formaldehyde cooking is of great potential to be a pretreatment method for a greenfield mill to produce fuel ethanol from hardwood. PMID:23127844

Jin, Yongcan; Yang, Linfeng; Jameel, Hasan; Chang, Hou-min; Phillips, Richard

2013-05-01

7

21 CFR 582.1131 - Aluminum sodium sulfate.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Aluminum sodium sulfate. 582.1131 Section 582...General Purpose Food Additives § 582.1131 Aluminum sodium sulfate. (a) Product. Aluminum sodium sulfate. (b) Conditions of...

2011-04-01

8

21 CFR 182.1131 - Aluminum sodium sulfate.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Aluminum sodium sulfate. 182.1131 Section 182...Purpose GRAS Food Substances § 182.1131 Aluminum sodium sulfate. (a) Product. Aluminum sodium sulfate. (b) Conditions of...

2011-04-01

9

21 CFR 182.1131 - Aluminum sodium sulfate.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Aluminum sodium sulfate. 182.1131 Section 182...Purpose GRAS Food Substances § 182.1131 Aluminum sodium sulfate. (a) Product. Aluminum sodium sulfate. (b) Conditions of...

2013-04-01

10

21 CFR 182.1131 - Aluminum sodium sulfate.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 2009-04-01 true Aluminum sodium sulfate. 182.1131 Section 182...Purpose GRAS Food Substances § 182.1131 Aluminum sodium sulfate. (a) Product. Aluminum sodium sulfate. (b) Conditions of...

2010-04-01

11

21 CFR 582.1131 - Aluminum sodium sulfate.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Aluminum sodium sulfate. 582.1131 Section 582...General Purpose Food Additives § 582.1131 Aluminum sodium sulfate. (a) Product. Aluminum sodium sulfate. (b) Conditions of...

2013-04-01

12

21 CFR 582.1131 - Aluminum sodium sulfate.  

...2014-04-01 2014-04-01 false Aluminum sodium sulfate. 582.1131 Section 582...General Purpose Food Additives § 582.1131 Aluminum sodium sulfate. (a) Product. Aluminum sodium sulfate. (b) Conditions of...

2014-04-01

13

21 CFR 182.1131 - Aluminum sodium sulfate.  

...2014-04-01 2014-04-01 false Aluminum sodium sulfate. 182.1131 Section 182...Purpose GRAS Food Substances § 182.1131 Aluminum sodium sulfate. (a) Product. Aluminum sodium sulfate. (b) Conditions of...

2014-04-01

14

21 CFR 582.1131 - Aluminum sodium sulfate.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Aluminum sodium sulfate. 582.1131 Section 582...General Purpose Food Additives § 582.1131 Aluminum sodium sulfate. (a) Product. Aluminum sodium sulfate. (b) Conditions of...

2012-04-01

15

21 CFR 182.1131 - Aluminum sodium sulfate.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Aluminum sodium sulfate. 182.1131 Section 182...Purpose GRAS Food Substances § 182.1131 Aluminum sodium sulfate. (a) Product. Aluminum sodium sulfate. (b) Conditions of...

2012-04-01

16

21 CFR 582.1131 - Aluminum sodium sulfate.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Aluminum sodium sulfate. 582.1131 Section 582...General Purpose Food Additives § 582.1131 Aluminum sodium sulfate. (a) Product. Aluminum sodium sulfate. (b) Conditions of...

2010-04-01

17

Multiple Lateral Transfers of Dissimilatory Sulfite Reductase Genes between Major Lineages of Sulfate-Reducing Prokaryotes  

PubMed Central

A large fragment of the dissimilatory sulfite reductase genes (dsrAB) was PCR amplified and fully sequenced from 30 reference strains representing all recognized lineages of sulfate-reducing bacteria. In addition, the sequence of the dsrAB gene homologs of the sulfite reducer Desulfitobacterium dehalogenans was determined. In contrast to previous reports, comparative analysis of all available DsrAB sequences produced a tree topology partially inconsistent with the corresponding 16S rRNA phylogeny. For example, the DsrAB sequences of several Desulfotomaculum species (low G+C gram-positive division) and two members of the genus Thermodesulfobacterium (a separate bacterial division) were monophyletic with ?-proteobacterial DsrAB sequences. The most parsimonious interpretation of these data is that dsrAB genes from ancestors of as-yet-unrecognized sulfate reducers within the ?-Proteobacteria were laterally transferred across divisions. A number of insertions and deletions in the DsrAB alignment independently support these inferred lateral acquisitions of dsrAB genes. Evidence for a dsrAB lateral gene transfer event also was found within the ?-Proteobacteria, affecting Desulfobacula toluolica. The root of the dsr tree was inferred to be within the Thermodesulfovibrio lineage by paralogous rooting of the alpha and beta subunits. This rooting suggests that the dsrAB genes in Archaeoglobus species also are the result of an ancient lateral transfer from a bacterial donor. Although these findings complicate the use of dsrAB genes to infer phylogenetic relationships among sulfate reducers in molecular diversity studies, they establish a framework to resolve the origins and diversification of this ancient respiratory lifestyle among organisms mediating a key step in the biogeochemical cycling of sulfur. PMID:11567003

Klein, Michael; Friedrich, Michael; Roger, Andrew J.; Hugenholtz, Philip; Fishbain, Susan; Abicht, Heike; Blackall, Linda L.; Stahl, David A.; Wagner, Michael

2001-01-01

18

Multiple sulfur isotope signatures of sulfite and thiosulfate reduction by the model dissimilatory sulfate-reducer, Desulfovibrio alaskensis str. G20  

PubMed Central

Dissimilatory sulfate reduction serves as a key metabolic carbon remineralization process in anoxic marine environments. Sulfate reducing microorganisms can impart a wide range in mass-dependent sulfur isotopic fractionation. As such, the presence and relative activity of these organisms is identifiable from geological materials. By extension, sulfur isotope records are used to infer the redox balance of marine sedimentary environments, and the oxidation state of Earth's oceans and atmosphere. However, recent work suggests that our understanding of microbial sulfate reduction (MSRs) may be missing complexity associated with the presence and role of key chemical intermediates in the reductive process. This study provides a test of proposed metabolic models of sulfate reduction by growing an axenic culture of the well-studied MSRs, Desulfovibrio alaskensis strain G20, under electron donor limited conditions on the terminal electron acceptors sulfate, sulfite or thiosulfate, and tracking the multiple S isotopic consequences of each condition set. The dissimilatory reduction of thiosulfate and sulfite produce unique minor isotope effects, as compared to the reduction of sulfate. Further, these experiments reveal a complex biochemistry associated with sulfite reduction. That is, under high sulfite concentrations, sulfur is shuttled to an intermediate pool of thiosulfate. Site-specific isotope fractionation (within thiosulfate) is very large (34? ~ 30‰) while terminal product sulfide carries only a small fractionation from the initial sulfite (34? < 10‰): a signature similar in magnitude to sulfate and thiosulfate reduction. Together these findings show that microbial sulfate reduction (MSR) is highly sensitive to the concentration of environmentally important sulfur-cycle intermediates (sulfite and thiosulfate), especially when thiosulfate and the large site-specific isotope effects are involved. PMID:25505449

Leavitt, William D.; Cummins, Renata; Schmidt, Marian L.; Sim, Min S.; Ono, Shuhei; Bradley, Alexander S.; Johnston, David T.

2014-01-01

19

Multiple sulfur isotope signatures of sulfite and thiosulfate reduction by the model dissimilatory sulfate-reducer, Desulfovibrio alaskensis str. G20.  

PubMed

Dissimilatory sulfate reduction serves as a key metabolic carbon remineralization process in anoxic marine environments. Sulfate reducing microorganisms can impart a wide range in mass-dependent sulfur isotopic fractionation. As such, the presence and relative activity of these organisms is identifiable from geological materials. By extension, sulfur isotope records are used to infer the redox balance of marine sedimentary environments, and the oxidation state of Earth's oceans and atmosphere. However, recent work suggests that our understanding of microbial sulfate reduction (MSRs) may be missing complexity associated with the presence and role of key chemical intermediates in the reductive process. This study provides a test of proposed metabolic models of sulfate reduction by growing an axenic culture of the well-studied MSRs, Desulfovibrio alaskensis strain G20, under electron donor limited conditions on the terminal electron acceptors sulfate, sulfite or thiosulfate, and tracking the multiple S isotopic consequences of each condition set. The dissimilatory reduction of thiosulfate and sulfite produce unique minor isotope effects, as compared to the reduction of sulfate. Further, these experiments reveal a complex biochemistry associated with sulfite reduction. That is, under high sulfite concentrations, sulfur is shuttled to an intermediate pool of thiosulfate. Site-specific isotope fractionation (within thiosulfate) is very large ((34)? ~ 30‰) while terminal product sulfide carries only a small fractionation from the initial sulfite ((34)? < 10‰): a signature similar in magnitude to sulfate and thiosulfate reduction. Together these findings show that microbial sulfate reduction (MSR) is highly sensitive to the concentration of environmentally important sulfur-cycle intermediates (sulfite and thiosulfate), especially when thiosulfate and the large site-specific isotope effects are involved. PMID:25505449

Leavitt, William D; Cummins, Renata; Schmidt, Marian L; Sim, Min S; Ono, Shuhei; Bradley, Alexander S; Johnston, David T

2014-01-01

20

Thermal energy storage composition comprising sodium sulfate decahydrate; sodium carbonate decahydrate; and sodium tetraborate decahydrate  

SciTech Connect

A thermal energy storage composition is disclosed that stores heat upon melting and releases heat upon solidification. It is composed of a mixture of sodium sulfate decahydrate, sodium carbonate decahydrate, sodium borate decahydrate and a thickening agent. Its good heat transfer characteristics, relatively high latent heat of fusion, low cost, and favorable melting point allow this material to be particularly useful for space heating applications.

Chen, J.C.

1981-09-29

21

Protective performances of two anti-graffiti treatments towards sulfite and sulfate formation in SO 2 polluted model environment  

NASA Astrophysics Data System (ADS)

Specific strategies for protection are being developed to counter both the staining and corrosive effects of polluted air in cities, as well as to allow for efficient removal of unwanted graffiti paintings. These protection strategies employ molecules with tailored functionalities, e.g. being hydrophobic, while maintaining porosity for molecular water vapour permeation. The present study employs SO 2 and water to probe the behaviors of two anti-graffiti treatments, a water-base fluoroalkylsiloxane ("Protectosil Antigraffiti" marketed by Degussa) and an organically modified silicate (Ormosil) synthesized from a polymer chain (polydimethyl siloxane, PDMS) and two network forming alkoxides (Zr propoxide and methyl triethoxy silane, MTES) dissolved in n-propanol, on five building materials, comprising limestone, aged lime mortar, hydrated cement mortar, granite, and brick material. The materials were exposed to a synthetic atmosphere for 20 h in a climate chamber, 0.78 ± 0.03 ppm of SO 2 and 95% RH. Diffuse reflectance Fourier transform infrared (DR-FTIR) spectra were registered before and after exposure in the climate chamber in the cases of both treated and untreated samples. DR-FTIR, scanning electron microscope (SEM) images and energy dispersive X-ray (EDX) analyses, suggest the anti-graffiti Ormosil to suppress formation of calcium sulfite hemihydrate (the primary initial product of the reaction of calcium compounds with SO 2 and water) on carbonate materials (limestone and lime mortar). In case of the granite, brick and cement mortar, Ormosil has a negligible influence on the SO 2 capture. While no sulfite formation was detected by DR-FTIR, gypsum is inferred to form due to metal oxides and minority compounds catalysed oxidation of sulfite to sulfate. In case of brick, this understanding finds support from SEM images as well as EDX. A priori presence of gypsum in hydrated cement mortars prevents positive identification by SEM. However, support for sulfur accumulation in hydrated cement mortar is provided by means of EDX. In case of a second anti-graffiti considered, Protectosil, no influence of the anti-graffiti treatment on the SO 2 uptake of any of the building materials was observed.

Carmona-Quiroga, Paula María; Panas, Itai; Svensson, Jan-Erik; Johansson, Lars-Gunnar; Blanco-Varela, María Teresa; Martínez-Ramírez, Sagrario

2010-11-01

22

21 CFR 173.385 - Sodium methyl sulfate.  

...Sodium methyl sulfate may be present in pectin in accordance with the following conditions...present as the result of methylation of pectin by sulfuric acid and methyl alcohol...exceed 0.1 percent by weight of the...

2014-04-01

23

21 CFR 173.385 - Sodium methyl sulfate.  

Code of Federal Regulations, 2013 CFR

...Sodium methyl sulfate may be present in pectin in accordance with the following conditions...present as the result of methylation of pectin by sulfuric acid and methyl alcohol...exceed 0.1 percent by weight of the...

2013-04-01

24

21 CFR 173.385 - Sodium methyl sulfate.  

Code of Federal Regulations, 2012 CFR

...Sodium methyl sulfate may be present in pectin in accordance with the following conditions...present as the result of methylation of pectin by sulfuric acid and methyl alcohol...exceed 0.1 percent by weight of the...

2012-04-01

25

21 CFR 173.385 - Sodium methyl sulfate.  

Code of Federal Regulations, 2011 CFR

...Sodium methyl sulfate may be present in pectin in accordance with the following conditions...present as the result of methylation of pectin by sulfuric acid and methyl alcohol...exceed 0.1 percent by weight of the...

2011-04-01

26

21 CFR 173.385 - Sodium methyl sulfate.  

Code of Federal Regulations, 2010 CFR

...Sodium methyl sulfate may be present in pectin in accordance with the following conditions...present as the result of methylation of pectin by sulfuric acid and methyl alcohol...exceed 0.1 percent by weight of the...

2010-04-01

27

Fluorescence Probe Studies of Gelatin-Sodium Dodecyl Sulfate Interactions  

E-print Network

Fluorescence Probe Studies of Gelatin-Sodium Dodecyl Sulfate Interactions P. C. Griffiths* and J. A dodecyl sulfate (SDS) micelles bound to gelatin have been studied by fluorescence using 8-anilino-1-naphththalene sulfonic acid (ANS) as probe. Like gelatin, ANS binds in the region of the micelle occupied

Bales, Barney

28

21 CFR 186.1797 - Sodium sulfate.  

Code of Federal Regulations, 2010 CFR

...7757-82-6), also known as Glauber's salt, occurs naturally and exists as colorless crystals or as a fine, white crystalline powder. It is prepared by the neutralization of sulfuric acid with sodium hydroxide. (b) The ingredient is...

2010-04-01

29

Synthesis and solid state properties of the 4-naphthyloxymethyl-2,2-dioxo-1,3,2-dioxathiolane, cyclic sulfate not available through sulfite oxidation procedure  

NASA Astrophysics Data System (ADS)

The chiral adrenoblocker propranolol precursor 4-naphthyloxymethyl-2,2-dioxo-1,3,2-dioxathiolane, 2, was obtained in racemic and scalemic form. It was found that sulfates 2 are practically unavailable through the standard Ru-catalyzed sulfite oxidation procedure, but could be obtained by the direct action of SO 2Cl 2 on the corresponding vicinal diols 3. The published properties of the sulfate were corrected. Thermodynamic characteristics and binary melting phase diagram were evaluated for compound 2 by DSC. The crystal structure of rac- and scal- 2 was established by single crystal X-ray analysis and the absolute configuration of scal- 2 was established by the Flack method. The flexible nature of the sulfur-containing cycle, and the sensitivity of the compound conformation to homo- and heterochiral crystal environment was demonstrated.

Bredikhina, Zemfira A.; Gubaidullin, Aidar T.; Bredikhin, Alexander A.

2010-12-01

30

Sodium sulfate - Deposition and dissolution of silica  

NASA Technical Reports Server (NTRS)

The hot-corrosion process for SiO2-protected materials involves deposition of Na2SO4 and dissolution of the protective SiO2 scale. Dew points for Na2SO4 deposition are calculated as a function of pressure, sodium content, and sulfur content. Expected dissolution regimes for SiO2 are calculated as a function of Na2SO4 basicity. Controlled-condition burner-rig tests on quartz verify some of these predicted dissolution regimes. The basicity of Na2SO4 is not always a simple function of P(SO3). Electrochemical measurements of an (Na2O) show that carbon creates basic conditions in Na2SO4, which explains the extensive corrosion of SiO2-protected materials containing carbon, such as SiC.

Jacobson, Nathan S.

1989-01-01

31

Thermodynamics of Lipid Membrane Solubilization by Sodium Dodecyl Sulfate  

Microsoft Academic Search

We provide a comprehensive thermodynamic description of lipid membrane dissolution by a charged detergent. To this end, we have studied the interactions between the anionic detergent sodium dodecyl sulfate (SDS) and the zwitterionic phospholipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) in dilute aqueous solution (10mM phosphate buffer, 154mM NaCl, pH 7.4). Thermodynamic parameters of vesicle solubilization and reconstitution, membrane partitioning, and micelle formation were

Sandro Keller; Heiko Heerklotz; Nadin Jahnke; Alfred Blume

2006-01-01

32

Stimulation of F 1ATPase activity by sodium dodecyl sulfate  

Microsoft Academic Search

F1-ATPase is a rotary molecular motor in which the ? subunit rotates inside the cylinder made of ?3?3 subunits. We have studied the effects of sodium dodecyl sulfate (SDS) on the rotational and ATP hydrolysis activities of F1-ATPase. Bulk hydrolysis activity at various SDS concentrations was examined at 2mM ATP. Maximal stimulation was obtained at 0.003% (w\\/v) SDS, the initial

Mohammad Delawar Hossain; Shou Furuike; Yasuhiro Onoue; Kengo Adachi; Masasuke Yoshida; Kazuhiko Kinosita Jr.

2010-01-01

33

Microorganisms with Novel Dissimilatory (Bi)Sulfite Reductase Genes Are Widespread and Part of the Core Microbiota in Low-Sulfate Peatlands ? †  

PubMed Central

Peatlands of the Lehstenbach catchment (Germany) house as-yet-unidentified microorganisms with phylogenetically novel variants of the dissimilatory (bi)sulfite reductase genes dsrAB. These genes are characteristic of microorganisms that reduce sulfate, sulfite, or some organosulfonates for energy conservation but can also be present in anaerobic syntrophs. However, nothing is currently known regarding the abundance, community dynamics, and biogeography of these dsrAB-carrying microorganisms in peatlands. To tackle these issues, soils from a Lehstenbach catchment site (Schlöppnerbrunnen II fen) from different depths were sampled at three time points over a 6-year period to analyze the diversity and distribution of dsrAB-containing microorganisms by a newly developed functional gene microarray and quantitative PCR assays. Members of novel, uncultivated dsrAB lineages (approximately representing species-level groups) (i) dominated a temporally stable but spatially structured dsrAB community and (ii) represented “core” members (up to 1% to 1.7% relative abundance) of the autochthonous microbial community in this fen. In addition, denaturing gradient gel electrophoresis (DGGE)- and clone library-based comparisons of the dsrAB diversity in soils from a wet meadow, three bogs, and five fens of various geographic locations (distance of ?1 to 400 km) identified that one Syntrophobacter-related and nine novel dsrAB lineages are widespread in low-sulfate peatlands. Signatures of biogeography in dsrB-based DGGE data were not correlated with geographic distance but could be explained largely by soil pH and wetland type, implying that the distribution of dsrAB-carrying microorganisms in wetlands on the scale of a few hundred kilometers is not limited by dispersal but determined by local environmental conditions. PMID:21169452

Steger, Doris; Wentrup, Cecilia; Braunegger, Christina; Deevong, Pinsurang; Hofer, Manuel; Richter, Andreas; Baranyi, Christian; Pester, Michael; Wagner, Michael; Loy, Alexander

2011-01-01

34

Microorganisms with novel dissimilatory (bi)sulfite reductase genes are widespread and part of the core microbiota in low-sulfate peatlands.  

PubMed

Peatlands of the Lehstenbach catchment (Germany) house as-yet-unidentified microorganisms with phylogenetically novel variants of the dissimilatory (bi)sulfite reductase genes dsrAB. These genes are characteristic of microorganisms that reduce sulfate, sulfite, or some organosulfonates for energy conservation but can also be present in anaerobic syntrophs. However, nothing is currently known regarding the abundance, community dynamics, and biogeography of these dsrAB-carrying microorganisms in peatlands. To tackle these issues, soils from a Lehstenbach catchment site (Schlöppnerbrunnen II fen) from different depths were sampled at three time points over a 6-year period to analyze the diversity and distribution of dsrAB-containing microorganisms by a newly developed functional gene microarray and quantitative PCR assays. Members of novel, uncultivated dsrAB lineages (approximately representing species-level groups) (i) dominated a temporally stable but spatially structured dsrAB community and (ii) represented "core" members (up to 1% to 1.7% relative abundance) of the autochthonous microbial community in this fen. In addition, denaturing gradient gel electrophoresis (DGGE)- and clone library-based comparisons of the dsrAB diversity in soils from a wet meadow, three bogs, and five fens of various geographic locations (distance of ?1 to 400 km) identified that one Syntrophobacter-related and nine novel dsrAB lineages are widespread in low-sulfate peatlands. Signatures of biogeography in dsrB-based DGGE data were not correlated with geographic distance but could be explained largely by soil pH and wetland type, implying that the distribution of dsrAB-carrying microorganisms in wetlands on the scale of a few hundred kilometers is not limited by dispersal but determined by local environmental conditions. PMID:21169452

Steger, Doris; Wentrup, Cecilia; Braunegger, Christina; Deevong, Pinsurang; Hofer, Manuel; Richter, Andreas; Baranyi, Christian; Pester, Michael; Wagner, Michael; Loy, Alexander

2011-02-01

35

Sulfite suppresses the mutagenic property of coffee.  

PubMed

The mutagenicity of instant and freshly brewed coffee on Salmonella typhimurium TA100 and TA98 without S9 mix was inactivated by sodium sulfite. Sulfite ion at a dose of 200 ppm almost completely inactivated the mutagenicity of coffee made in the ordinary way (5-15 mg dry weight/ml). Sodium bisulfite and potassium metabisulfite had similar effects. On the contrary, L-ascorbic acid enhanced the mutagenicity of coffee. Sodium sulfite also inactivated the phage-inducing activity of coffee in inductest III. Sodium sulfite completely suppressed the mutagenicities of 1,2-dicarbonyls, namely diacetyl and glyoxal. Diacetyl is present in coffee, beer, butter and other foods and drinks. Because sodium sulfite, sodium bisulfite and potassium metabisulfite are widely used as food additives, they should be useful in reducing the levels of mutagens in foods. PMID:6217422

Suwa, Y; Nagao, M; Kosugi, A; Sugimura, T

1982-12-01

36

40 CFR 63.444 - Standards for the pulping system at sulfite processes.  

Code of Federal Regulations, 2010 CFR

... false Standards for the pulping system at sulfite processes...Pollutants from the Pulp and Paper Industry § 63.444 Standards for the pulping system at sulfite processes...or sodium-based sulfite pulping process shall: (i)...

2010-07-01

37

Destabilization of yttria-stabilized zirconia induced by molten sodium vanadate-sodium sulfate melts  

NASA Technical Reports Server (NTRS)

The extent of surface destabilization of ZrO2 - 8 wt percent Y2O3 ceramic disks was determined after exposure to molten salt mixtures of sodium sulfate containing up to 15 mole percent sodium metavanadate (NaVO3) at 1173 K. The ceramic surface was observed to transform from the cubic/tetragonal to monoclinic phase, concurrent with chemical changes in the molten salt layer in contact with the ceramic. Significant attack rates were observed in both pure sulfate and metavanadate sulfate melts. The rate of attack was found to be quite sensitive to the mole fraction of vanadate in the molten salt solution and the partial pressure of sulfur trioxide in equilibrium with the salt melt. The observed parabolic rate of attack is interpreted to be caused by a reaction controlled by diffusion in the salt that penetrates into the porous layer formed by the destabilization. The parabolic rate constant in mixed sodium metavanadate - sodium sulfate melts was found to be proportional to the SO3 partial pressure and the square of the metavanadate concentration. In-situ Raman spectroscopic measurements allowed simultaneous observations of the ceramic phases and salt chemistry during the attack process.

Nagelberg, A. S.; Hamilton, J. C.

1985-01-01

38

Flow-injection analysis of two fluoquinolones by the sensitizing effect of terbium(III) on chemiluminescence of the potassium permanganate–sodium sulfite system  

Microsoft Academic Search

A simple, rapid and sensitive method for the determination of two fluoquinolones (FQs), enoxacin (ENX) and ofloxacin (OFLX) is described by using flow injection analysis with potassium permanganate–sodium sulfite chemiluminescence detection. The calibration graphs for ENX and OFLX are linear in the range of 8.0×10?10–1.0×10?5 and 1.0×10?9–1.0×10?6 mol l?1, respectively. The 3? limits of detection are 2.4×10?10 mol l?1 for

Lin Yi; Huichun Zhao; Shilv Chen; Linpei Jin; Dongdong Zheng; Zhenglong Wu

2003-01-01

39

Sulfite Reductase Defines a Newly Discovered Bottleneck for Assimilatory Sulfate Reduction and Is Essential for Growth and Development in Arabidopsis thaliana[C][W  

PubMed Central

The role of sulfite reductase (SiR) in assimilatory reduction of inorganic sulfate to sulfide has long been regarded as insignificant for control of flux in this pathway. Two independent Arabidopsis thaliana T-DNA insertion lines (sir1-1 and sir1-2), each with an insertion in the promoter region of SiR, were isolated. sir1-2 seedlings had 14% SiR transcript levels compared with the wild type and were early seedling lethal. sir1-1 seedlings had 44% SiR transcript levels and were viable but strongly retarded in growth. In mature leaves of sir1-1 plants, the levels of SiR transcript, protein, and enzymatic activity ranged between 17 and 28% compared with the wild type. The 28-fold decrease of incorporation of 35S label into Cys, glutathione, and protein in sir1-1 showed that the decreased activity of SiR generated a severe bottleneck in the assimilatory sulfate reduction pathway. Root sulfate uptake was strongly enhanced, and steady state levels of most of the sulfur-related metabolites, as well as the expression of many primary metabolism genes, were changed in leaves of sir1-1. Hexose and starch contents were decreased, while free amino acids increased. Inorganic carbon, nitrogen, and sulfur composition was also severely altered, demonstrating strong perturbations in metabolism that differed markedly from known sulfate deficiency responses. The results support that SiR is the only gene with this function in the Arabidopsis genome, that optimal activity of SiR is essential for normal growth, and that its downregulation causes severe adaptive reactions of primary and secondary metabolism. PMID:20424176

Khan, Muhammad Sayyar; Haas, Florian Heinrich; Allboje Samami, Arman; Moghaddas Gholami, Amin; Bauer, Andrea; Fellenberg, Kurt; Reichelt, Michael; Hänsch, Robert; Mendel, Ralf R.; Meyer, Andreas J.; Wirtz, Markus; Hell, Rüdiger

2010-01-01

40

Amperometric Determination of Sulfite by Gas Diffusion-Sequential Injection with Boron-Doped Diamond Electrode  

PubMed Central

A gas diffusion sequential injection system with amperometric detection using a boron-doped diamond electrode was developed for the determination of sulfite. A gas diffusion unit (GDU) was used to prevent interference from sample matrices for the electrochemical measurement. The sample was mixed with an acid solution to generate gaseous sulfur dioxide prior to its passage through the donor channel of the GDU. The sulfur dioxide diffused through the PTFE hydrophobic membrane into a carrier solution of 0.1M phosphate buffer (pH 8)/0.1% sodium dodecyl sulfate in the acceptor channel of the GDU and turned to sulfite. Then the sulfite was carried to the electrochemical flow cell and detected directly by amperometry using the boron-doped diamond electrode at 0.95 V (versus Ag/AgCl). Sodium dodecyl sulfate was added to the carrier solution to prevent electrode fouling. This method was applicable in the concentration range of 0.2-20 mg SO32?/L and a detection limit (S/N = 3) of 0.05 mg SO32?/L was achieved. This method was successfully applied to the determination of sulfite in wines and the analytical results agreed well with those obtained by iodimetric titration. The relative standard deviations for the analysis of sulfite in wines were in the range of 1.0-4.1 %. The sampling frequency was 65 h?1.

Chinvongamorn, Chakorn; Pinwattana, Kulwadee; Praphairaksit, Narong; Imato, Toshihiko; Chailapakul, Orawon

2008-01-01

41

Growth and physiological responses of five cotton genotypes to sodium chloride and sodium sulfate saline water irrigation  

Technology Transfer Automated Retrieval System (TEKTRAN)

This study was conducted to investigate the salt tolerance of five cotton genotypes [three Gossypium hirsutum L. (DN 1, DP 491, and FM 989) and two G. barbadense L. (Cobalt and Pima S-7)] under sodium chloride or sodium sulfate salinity conditions at similar osmotic potentials (100 mM sodium chlorid...

42

Dynamics of sodium dodecyl sulfate micelles in polyacrylamide gels  

NASA Astrophysics Data System (ADS)

Hydrophilic polyacrylamide gels exhibit interesting elastic properties which can be probed by dynamic light scattering. The dynamic structure factors of such gels and of gels which were polymerized in the presence of high concentrations of sodium dodecyl sulfate (SDS) micelles were measured. It was found that the gels containing SDS decay initially according to a stretched exponential, followed by a long time simple exponential decay, whereas the pure gel decay is single exponential at all times. Furthermore, the initial decays of all SDS/gel systems are nearly identical, while the long-time decays are clearly a function of SDS concentration. We interpret the initial decay as associated with local polyacrylamide elasticity unaffected by the presence of the micelles and the long time decays as characteristic of gel modes slowed by the various densities of SDS micelles.

Reyna, A.; Liu, Yingjie; van Winkle, David H.

1998-03-01

43

Sodium Dodecyl Sulfate Induces Plasminogen Activator Inhibitor Type 2 Expression in Epidermal Keratinocytes In Vivo and In Vitro  

Microsoft Academic Search

The detergent sodium dodecyl sulfate is a well-known inducer of irritant contact dermatitis. In this study we show that sodium dodecyl sulfate induces the serine proteinase inhibitor, plasminogen activator inhibitor type 2, in epidermal keratinocytes. The enhancement in plasminogen activator inhibitor type 2 mRNA and antigen is observed both when sodium dodecyl sulfate is applied topically to normal human skin

Nancy M Chung; Christine M Marshall; James J Leyden; Robert M Lavker; Pamela J Jensen; Barbara C Risse Marsh

2001-01-01

44

Microcapsules based on glycinin-sodium dodecyl sulfate complex coacervation.  

PubMed

Microcapsules processed by complex coacervation were prepared using hexadecane for the oil phase and glycinin (a soybean storage protein)-sodium dodecyl sulfate (SDS) as the main wall-forming material. The study underlines the essential role of SDS, which, by the way of [glycinin(+)-SDS(-)] insoluble complex formation, allowed the precipitation of proteins around oil droplets. Moreover, particular attention was attributed to the study of suitable conditions of glycinin cross-linking with glutaraldehyde. The reticulation step was performed at pH 4.0 and it was observed that the precipitated state of proteins increased considerably the efficiency of the cross-linking reaction. Analysis of the reactional medium after each main step of the process (emulsification, complex coacervation, cross-linking) allowed the follow-up and characterization of microcapsule formation. Optimization of different process parameters such as glycinin concentration, glycinin/SDS/glutaraldehyde ratios, pH and the kinetics of cross-linking allowed the encapsulation of the totality of oil and the use of more than 98% of initially introduced proteins for the microcapsule wall formation. PMID:14718186

Lazko, J; Popineau, Y; Renard, D; Legrand, J

2004-02-01

45

Agaricus bisporus Attenuates Dextran Sulfate Sodium-Induced Colitis.  

PubMed

Abstract Agaricus bisporus (white button mushroom, WBM) is widely consumed in most countries and is reported to have anti-inflammatory and antioxidant activities. However, little is known regarding its effects in dextran sulfate sodium (DSS)-induced colitis, which are related to dysfunction of intestinal immunity. The aim of the present study was to investigate the effects of WBMs in an animal model of DSS-induced colitis. Male, 4-week-old ICR mice (n=10 per group) were fed a normal diet with or without 10% WBM for 4 weeks, and colitis was induced by 3% DSS in drinking water for 7 days. WBMs prevented DSS-induced shortening of colon length (P=.033) and diminished diarrhea (P=.049) and gross bleeding (P=.001), resulting in a decreased disease activity index. Results of histological analysis showed that WBMs suppressed mucosal damage. In addition, WBMs attenuated the DSS-induced increase in myeloperoxidase activity (P=.012) and upregulation of proinflammatory cytokine tumor necrosis factor-? (P=.020) in the colon segment. Taken together, these findings suggest a possible role for the WBM as an immunomodulator that can prevent and/or treat ulcerative colitis. PMID:25357009

Um, Min Young; Park, Jae Ho; Gwon, So Young; Ahn, Jiyun; Jung, Chang Hwa; Ha, Tae Youl

2014-12-01

46

Dextran sulfate sodium inhibits alanine synthesis in Caco-2 cells.  

PubMed

To understand and characterize the pathogenic mechanisms of inflammatory bowel disease, dextran sulfate sodium (DSS) has been used to induce acute and chronic colitis in animal models by causing intestinal epithelium damage. The mechanism of action of DSS in producing this outcome is not well understood. In an effort to understand how DSS might impact epithelial cell metabolism, we studied the intestinal epithelial cell line Caco-2 incubated with 1% DSS over 56 hours using (1)H NMR spectroscopy. We observed no difference in cell viability as compared to control cultures, and an approximately 1.5-fold increase in IL-6 production upon incubation with 1% DSS. The effect on Caco-2 cell metabolism as measured through changes in the concentration of metabolites in the cell supernatant included a three-fold decrease in the concentration of alanine. Given that the concentrations of other amino acids in the cell culture supernatant were not different between treated and control cultures over 56 hours suggest that DSS inhibits alanine synthesis, specifically alanine aminotransferase, without affecting other key metabolic pathways. The importance of alanine aminotransferase in inflammatory bowel disease is discussed. PMID:21731444

Ye, Zhong; Mishchuk, Darya O; Stephens, Natasha S; Slupsky, Carolyn M

2011-01-01

47

Sodium sulfate heptahydrate: a synchrotron energy-dispersive diffraction study of an elusive metastable hydrated salt   

E-print Network

We describe an unusual application of synchrotron energy-dispersive diffraction with hard X-rays to obtain structural information on metastable sodium sulfate heptahydrate. This hydrate was often mentioned in nineteenth ...

Hamilton, Andrea; Hall, Christopher

2008-01-01

48

Structural Insights into Sulfite Oxidase Deficiency  

SciTech Connect

Sulfite oxidase deficiency is a lethal genetic disease that results from defects either in the genes encoding proteins involved in molybdenum cofactor biosynthesis or in the sulfite oxidase gene itself. Several point mutations in the sulfite oxidase gene have been identified from patients suffering from this disease worldwide. Although detailed biochemical analyses have been carried out on these mutations, no structural data could be obtained because of problems in crystallizing recombinant human and rat sulfite oxidases and the failure to clone the chicken sulfite oxidase gene. We synthesized the gene for chicken sulfite oxidase de novo, working backward from the amino acid sequence of the native chicken liver enzyme by PCR amplification of a series of 72 overlapping primers. The recombinant protein displayed the characteristic absorption spectrum of sulfite oxidase and exhibited steady state and rapid kinetic parameters comparable with those of the tissue-derived enzyme. We solved the crystal structures of the wild type and the sulfite oxidase deficiency-causing R138Q (R160Q in humans) variant of recombinant chicken sulfite oxidase in the resting and sulfate-bound forms. Significant alterations in the substrate-binding pocket were detected in the structure of the mutant, and a comparison between the wild type and mutant protein revealed that the active site residue Arg-450 adopts different conformations in the presence and absence of bound sulfate. The size of the binding pocket is thereby considerably reduced, and its position relative to the cofactor is shifted, causing an increase in the distance of the sulfur atom of the bound sulfate to the molybdenum.

Karakas,E.; Wilson, H.; Graf, T.; Xiang, S.; Jaramillo-Busquets, S.; Rajagopalan, K.; Kisker, C.

2005-01-01

49

Comparison of Solubilization Capacity of Resveratrol in Sodium 3?,12?-Dihydroxy-7-oxo-5?-cholanoate and Sodium Dodecyl Sulfate  

PubMed Central

In this study we investigated resveratrol (trans-3,5,4?-trihydroxystilbene) solubilization with sodium 3?,12?-dihydroxy-7-oxo-5?-cholanoate (S7-OD) and sodium dodecyl sulfate (SDS). The investigation was aimed at determining whether large spherical micelles (SDS) or small longitudinal micelles (S7-OD) are more convenient for incorporation of resveratrol. Also, we studied resveratrol behavior in mixed micelles with mentioned surfactants using spectroflourimetric method as well as the effects of sodium chloride and urea on resveratrol solubilization capacity in the applied surfactants. Resveratrol solubilization curve was different in the investigated surfactants. Resveratrol solubilization curve for sodium 3?,12?-dihydroxy-7-oxo-5?-cholanoate at concentration 0.9 CMC reached saturation level of 60% dissolved resveratrol. The curve for sodium dodecyl sulfate was linear within the whole range of the investigated concentration; resveratrol solubilization rate reached 13% at 2 CMC. In S7-OD, NaCl increased capacity of resveratrol solubilization up to 1.4 CMC surfactant concentration, whilst maximum level of dissolved resveratrol (90%) was observed at 0.9 CMC. In SDS, NaCl decreased resveratrol solubilization capacity. Urea reduced resveratrol solubilization rate in sodium 3?,12?-dihydroxy-7-oxo-5?-cholanoate, whereas it had inverse effect in sodium dodecyl sulfate. The obtained results strongly suggest that structure, that is, shape, of the surfactant micelles significantly affects their capacity of resveratrol solubilization. Also, presence of NaCl and urea influences solubilization capacities of investigated surfactants. PMID:24688374

Cveji?, Jelena; Poša, Mihalj

2014-01-01

50

Time measurement-visual analysis of L-cysteine using the autocatalytic sodium sulfite/hydrogen peroxide reaction system and its application to length detection-flow analysis.  

PubMed

Trace amounts of L-cysteine can function as a trigger, i.e., reaction initiator, in the autocatalytic sodium sulfite/hydrogen peroxide reaction system. Rapidly changing of pH after induction time is visually confirmed by color changing of bromothymol blue in this autocatalytic reaction. Based on this finding, microg L(-1) levels of L-cysteine were measured over time using the autocatalytic reaction system. The determination range using the above method was 5.0 x 10(-8)-2.5 x 10(-6)M, the detection limit (3 sigma) was 1.8 x 10(-8)M (1.94 microg L(-1)), and the relative standard deviation was 2.41% at an l-cysteine concentration of 5 x 10(-7)M (n=5). This method was also applied to length detection-flow injection analysis. The determination range for the flow injection analysis was 2.0 x 10(-7)-1.0 x 10(-5)M. The detection limit (3 sigma) was 1.4 x 10(-7)M (17.0 microg L(-1)), and the relative standard deviation was 0.91% at an initial L-cysteine concentration of 10(-6)M (n=5). PMID:19615525

Kato, Jun; Chiba, Michihito; Igarashi, Shukuro

2009-09-15

51

Comparative study on the mechanisms of rotavirus inactivation by sodium dodecyl sulfate and ethylenediaminetetraacetate.  

PubMed Central

This report describes a comparative study on the effects of the anionic detergent sodium dodecyl sulfate and the chelating agent ethylenediaminetetraacetate on purified rotavirus SA-11 particles. Both chemicals readily inactivated rotavirus at quite low concentrations and under very mild conditions. In addition, both agents modified the viral capsid and prevented the adsorption of inactivated virions to cells. Capsid damage by ethylenediaminetetraacetate caused a shift in the densities of rotavirions from about 1.35 to about 1.37 g/ml and a reduction in their sedimentation coefficients. Sodium dodecyl sulfate, on the other hand, did not detectably alter either of these physical properties of rotavirions. Both agents caused some alteration of the isoelectric points of the virions. Finally, analysis of rotavirus proteins showed that ethylenediaminetetraacetate caused the loss of two protein peaks from the electrophoretic pattern of virions but sodium dodecyl sulfate caused the loss of only one of these same protein peaks. PMID:6250474

Ward, R L; Ashley, C S

1980-01-01

52

Structure-Based Alteration of Substrate Specificity and Catalytic Activity of Sulfite Oxidase from Sulfite Oxidation to Nitrate Reduction  

SciTech Connect

Eukaryotic sulfite oxidase is a dimeric protein that contains the molybdenum cofactor and catalyzes the metabolically essential conversion of sulfite to sulfate as the terminal step in the metabolism of cysteine and methionine. Nitrate reductase is an evolutionarily related molybdoprotein in lower organisms that is essential for growth on nitrate. In this study, we describe human and chicken sulfite oxidase variants in which the active site has been modified to alter substrate specificity and activity from sulfite oxidation to nitrate reduction. On the basis of sequence alignments and the known crystal structure of chicken sulfite oxidase, two residues are conserved in nitrate reductases that align with residues in the active site of sulfite oxidase. On the basis of the crystal structure of yeast nitrate reductase, both positions were mutated in human sulfite oxidase and chicken sulfite oxidase. The resulting double-mutant variants demonstrated a marked decrease in sulfite oxidase activity but gained nitrate reductase activity. An additional methionine residue in the active site was proposed to be important in nitrate catalysis, and therefore, the triple variant was also produced. The nitrate reducing ability of the human sulfite oxidase triple mutant was nearly 3-fold greater than that of the double mutant. To obtain detailed structural data for the active site of these variants, we introduced the analogous mutations into chicken sulfite oxidase to perform crystallographic analysis. The crystal structures of the Mo domains of the double and triple mutants were determined to 2.4 and 2.1 {angstrom} resolution, respectively.

Qiu, James A.; Wilson, Heather L.; Rajagopalan, K.V. (Duke)

2012-04-18

53

Oxidation and Reduction of Sulfite by Chloroplasts and Formation of Sulfite Addition Compounds 1  

PubMed Central

After exposing intact chloroplasts isolated from spinach (Spinacia oleracea L. cv Yates) and capable of photoreducing CO2 at high rates to different concentrations of radioactive sulfite in the light or in the dark, 35SO2 and H235S were removed from the acidified suspensions in a stream of nitrogen. Remaining activity could be fractionated into sulfate, organic sulfides, and sulfite addition compounds. When chloroplast suspensions contained catalase, superoxide dismutase and O-acetylserine, the oxidation of sulfite to sulfate was slower in the light than the reductive formation of sulfides that exhibited a maximum rate of about 2 micromoles per milligram chlorophyll per hour, equivalent to about 1% of maximum carbon assimilation. Botht the oxidative and the reductive detoxification of sulfite were very slow in the dark. Oxidation was somewhat, but not much, accelerated in the light in the absence of O-acetylserine, which caused a dramatic decrease in the formation of organic sulfides and an equally dramatic increase in the concentration of sulfite addition compounds whose formation was light-dependent. The sulfite addition compounds were not identified. Addition compounds did not accumulate in the dark. In the light, the electron transport inhibitor 3-(3,4-dichlorophenyl)-1,1-dimethylurea, diuron, decreased not only the reduction, but also the oxidation of sulfite and the formation of addition compounds. PMID:16668703

Dittrich, Andreas P. M.; Pfanz, Hardy; Heber, Ulrich

1992-01-01

54

Thermodynamics of aqueous sodium sulfate from the temperatures 273 K to 373 K and mixtures of aqueous sodium sulfate and sulfuric acid at 298.15 K  

SciTech Connect

New isopiestic vapor-pressure measurements on the aqueous system {l_brace}(1{minus}y)H{sub 2}SO{sub 4}+yNA{sub 2}SO{sub 4}{r_brace} along with earlier experimental investigations that span the range from y=0 to y=1 and infinitely dilute to supersaturated molalities have been analyzed in terms of the Pitzer ion-interaction model. Refined ion-interaction parameters for aqueous sodium sulfate valid over the temperature range 273 K to 373 K have been calculated and used for analyzing results for mixtures containing sulfuric acid and sodium sulfate at 298.15 K. Analysis of experimental results for these aqueous mixtures required explicit consideration of the dissociation reaction of bisulfate ion. Previous treatments of aqueous sulfuric acid and subsequently the bisulfate dissociation equilibrium valid in the range 273 K to 343 K were employed as a first approximation in representing the mixed solutions. Two sets of Pitzer ion-interaction parameters are presented for (sodium sulfate + sulfuric acid). The validity of the first set is limited in ionic strength and molality to saturated solutions of pure aqueous sodium sulfate (4 mol{center_dot}kg{sup {minus}1}). The second set of parameters corresponds to a slightly less precise representation but is valid over the entire range of experimental results considered. Both sets of parameters provide a more complete description of pure sulfuric acid solutions because of the removal of various redundancies of ion-interaction parameters. The specific ion-interaction terms used and the overall fitting procedure are described as well as selected examples of relevant thermodynamic calculations in the mixed system Na{sub 2}SO{sub 4}-H{sub 2}SO{sub 4}-H{sub 2}O. 33 refs., 6 figs., 5 tabs.

Hovey, J.K.; Pitzer, K.S. [Lawrence Berkeley Lab., CA (United States); Rard, J.A. [Lawrence Livermore National Lab., CA (United States)

1991-07-01

55

Thermodynamics of aqueous sodium sulfate from the temperatures 273 K to 373 K and mixtures of aqueous sodium sulfate and sulfuric acid at 298. 15 K  

SciTech Connect

New isopiestic vapor-pressure measurements on the aqueous system {l brace}(1{minus}y)H{sub 2}SO{sub 4}+yNA{sub 2}SO{sub 4}{r brace} along with earlier experimental investigations that span the range from y=0 to y=1 and infinitely dilute to supersaturated molalities have been analyzed in terms of the Pitzer ion-interaction model. Refined ion-interaction parameters for aqueous sodium sulfate valid over the temperature range 273 K to 373 K have been calculated and used for analyzing results for mixtures containing sulfuric acid and sodium sulfate at 298.15 K. Analysis of experimental results for these aqueous mixtures required explicit consideration of the dissociation reaction of bisulfate ion. Previous treatments of aqueous sulfuric acid and subsequently the bisulfate dissociation equilibrium valid in the range 273 K to 343 K were employed as a first approximation in representing the mixed solutions. Two sets of Pitzer ion-interaction parameters are presented for (sodium sulfate + sulfuric acid). The validity of the first set is limited in ionic strength and molality to saturated solutions of pure aqueous sodium sulfate (4 mol{center dot}kg{sup {minus}1}). The second set of parameters corresponds to a slightly less precise representation but is valid over the entire range of experimental results considered. Both sets of parameters provide a more complete description of pure sulfuric acid solutions because of the removal of various redundancies of ion-interaction parameters. The specific ion-interaction terms used and the overall fitting procedure are described as well as selected examples of relevant thermodynamic calculations in the mixed system Na{sub 2}SO{sub 4}-H{sub 2}SO{sub 4}-H{sub 2}O. 33 refs., 6 figs., 5 tabs.

Hovey, J.K.; Pitzer, K.S. (Lawrence Berkeley Lab., CA (United States)); Rard, J.A. (Lawrence Livermore National Lab., CA (United States))

1991-07-01

56

In situ characterization of elusive salt hydrates. The crystal structures of the heptahydrate and octahydrate of sodium sulfate.  

PubMed

An important intermediate phase in the crystallization of aqueous solutions of sodium sulfate is the highly metastable sodium sulfate heptahydrate (Na(2)SO(4).7H(2)O). This has been structurally characterized for the first time by in situ single crystal X-ray diffraction. The crystal structure shows that each sodium cation is octahedrally coordinated to water molecules, with a slight distortion due to one of the water molecules being disordered. The hydrated sodium cations are hydrogen-bonded to form a three-dimensional bonded network, which is markedly different from the architecture of one-dimensional bonded chains observed in sodium sulfate decahydrate (mirabilite). This major structural difference explains the reconstructive nature of the transformation observed between the heptahydrate and mirabilite. High-pressure crystallization of a 3.41 mol/kg water aqueous solution of sodium sulfate at 1.54 GPa in a diamond-anvil cell resulted in the formation of a previously unknown sodium sulfate hydrate, which we have determined by single crystal X-ray diffraction methods to be an octahydrate, Na(2)SO(4).8H(2)O. In this structure the sulfate ions are coordinated directly to sodium ions. This resembles anhydrous sodium sulfate (thenardite) but contrasts with the heptahydrate and decahydrate in which the sodium ions are coordinated exclusively by water molecules. This observation demonstrates how the delicate balance of inter- and intramolecular bonds in the crystal structure can be significantly altered by the application of pressure. PMID:19053442

Oswald, Iain D H; Hamilton, Andrea; Hall, Christopher; Marshall, William G; Prior, Timothy J; Pulham, Colin R

2008-12-31

57

Sulfate Flux in High Sodium Cat Red Cells  

Microsoft Academic Search

The transport of radioactive sulfate in cat red cells has been studied. The rate constant for 3 5SO4 inward movement under steady-state conditions is 0.24 -- 0.02\\/hr. This movement was found to be sensitive to osmotic changes in cell volume and to the nature of anions in the incubation medium; it in- creases with increasing cell volume and decreases with

R. I. Sha'afi; E. PASCOE

1972-01-01

58

Multiple sulfur isotope signatures of sulfite and thiosulfate reduction by the model dissimilatory sulfate-reducer, Desulfovibrio alaskensis str. G20  

E-print Network

Dissimilatory sulfate reduction serves as a key metabolic carbon remineralization process in anoxic marine environments. Sulfate reducing microorganisms can impart a wide range in mass-dependent sulfur isotopic fractionation. ...

Leavitt, William D.

59

Analysis of sperm antigens by sodium dodecyl sulfate gel/protein blot radioimmunobinding method  

SciTech Connect

A radioimmunobinding method based on the blotting of renatured proteins from sodium dodecyl sulfate gels on to nitrocellulose filter papers was developed to analyze the sperm antigens that elicit serum anti-sperm antibodies. In rabbits, serum anti-sperm antibodies were raised by immunization with homologous epididymal spermatozoa mixed with complete Freund's adjuvant. The raised antisera from either male or female rabbits were shown to react with three major sperm protein bands on sodium dodecyl sulfate gels with the corresponding molecular weights of about 70,000 +/- 5000, 14,000, and 13,000, respectively. In humans, the monoclonal antibodies against human sperm were raised by a hybridoma technique. Out of six independent hybrid cell lines that were generated, three of them were shown to secrete immunoglobulins that react with the same two protein bands on sodium dodecyl sulfate gels, which have the approximate molecular weight of 10,000. The same procedure was also used to analyze human serum samples that were shown to contain anti-sperm antibodies by the known techniques. Unique sperm antigens that elicit anti-sperm antibodies in humans were identified and correlated. The results of this study suggest that sodium dodecyl sulfate gel/protein blot radioimmunobinding method may be a sensitive and useful tool for the study of sperm antigens that elicit autoimmune responses and their association with human infertility.

Lee, C.Y.G. (Univ. of British Columbia, Vancouver, Canada); Huang, Y.S.; Hu, P.C.; Gomel, V.; Menge, A.C.

1982-06-01

60

Temperature-Controlled Vesicle Aggregation in the Mixed System of Sodium n-Dodecyl Sulfate/  

E-print Network

Temperature-Controlled Vesicle Aggregation in the Mixed System of Sodium n-Dodecyl Sulfate/ n. In Final Form: January 27, 2005 Temperature-controlled vesicle aggregation was investigated in a catanionic place as the temperature reached the critical value (Tc). Tc can be adjusted by the variations

Huang, Jianbin

61

Thermodynamics of Sodium Dodecyl Sulfate (SDS) Micellization: An Undergraduate Laboratory Experiment  

ERIC Educational Resources Information Center

An undergraduate laboratory experiment is presented that allows a thermodynamic characterization of micelle formation of sodium dodecyl sulfate (SDS) in aqueous solutions. The critical micelle concentration (CMC) and the degree of micelle ionization (alpha) are obtained at different temperatures by conductimetry. The molar standard free energy…

Marcolongo, Juan P.; Mirenda, Martin

2011-01-01

62

NUCLATION PAR LE BORAX DU SULFATE DE SODIUM DISPERS. APPLICATION POSSIBLE AU STOCKAGE THERMIQUE  

E-print Network

L-359 NUCL�ATION PAR LE BORAX DU SULFATE DE SODIUM DISPERS�. APPLICATION POSSIBLE AU STOCKAGE un intérêt pour la réalisation de stockage thermique. Abstract. 2014 The crystallization of droplets stockage thermique. Mais sous forme macroscopique le rendement du stockage baisse a chaque cycle du fait de

Boyer, Edmond

63

DETERMINATION OF SURFACTANT SODIUM LAURYL ESTHER SULFATE BY ION PAIRING CHROMATOGRAPHY WITH SUPPRESED CONDUCTIVITY DETECTION  

EPA Science Inventory

A method for the determination of the anionic Steol CS-330 surfactant is described. S-330 is a complex mixture of oligomers due to the various sizes of fatty alcohols and the number of moles of the ethoxylation. he main component of CS-330 is sodium lauryl ether sulfate (SLES). i...

64

DETERMINATION OF SURFACTANT SODIUM LAURYL ETHER SULFATE BY ION PAIRING CHROMATOGRAPHY WITH SUPPRESSED CONDUCTIVITY DETECTION  

EPA Science Inventory

A method for the determination of the anionic Steol CS-330 surfactant is described. CS-330 is a complex mixture of oligomers due to the various sizes of fatty alcohols and the number of moles of the ethoxylation. The main component of CS-330 is sodium lauryl ether sulfate (SLES)....

65

Modulation of heparan sulfate biosynthesis by sodium butyrate in recombinant CHO cells.  

PubMed

Sodium butyrate, a histone deacetylase inhibitor, has been used to improve transgene expression in Chinese hamster ovary (CHO) cells. The current study explores the impact of butyrate treatment on heparan sulfate (HS) biosynthesis and structural composition in a recombinant CHO-S cell line expressing enzymes in the heparin (HP)/(HS) biosynthetic pathway (Dual-10 stably expressing NDST2 and HS3st1). Flow cytometric analysis showed that antithrombin binding was increased in Dual-10 cells and basic fibroblast growth factor binding was decreased in response to sodium butyrate treatment. The results were in agreement with the AMAC-LCMS (2-aminoacridine-tagged HS/HP analysis by liquid chromatography mass spectrometry) data that showed that there was an increase in heparan sulfate tri-sulfated disaccharides and a decrease in N-sulfated disaccharides in the butyrate-treated cells. However, we could not detect any changes in the chondroitin sulfate pathway in Dual-10 cells treated with butyrate. The current study is the first to report the effect of butyrate on glycosaminoglycan profiles. PMID:24468831

Datta, Payel; Yang, Bo; Linhardt, Robert J; Sharfstein, Susan T

2015-03-01

66

Effect of sodium sulfate on the gelling behavior of agarose and water structure inside gel networks.  

PubMed

Agarose hydrogels which constitute a special class of soft matter are undoubtedly one of the most studied biopolymer gels. However, certain issues such as why the sulfate salts and sulfate content in the agarose molecules reduce the gel strength are still not very clear. The present work provides a detailed analysis of structural changes with respect to coil-helix transition or aggregation of helices in the aqueous agarose solutions and hydrogels that accompanied the systematic addition of sodium sulfate. A combined approach which includes the differential scanning calorimetry and temperature-dependent vacuum-ultraviolet circular dichroism measurements permitted the accurate estimates of the energy changes for coil-helix transition and helix-helix interactions. The hydration process of agarose molecule investigated from differential scanning calorimetry and concentration-dependent ultrasonic measurements indicated the loss of both the freeze bound and nonfreezable water molecules with the increase of sulfate content in the solution. Temperature-dependent fluorescence measurements using pyrene as a probe indicated polarity changes when the gel network is created in waters of different salt concentration. Changes in the hydrogen bonding of the water molecules confined in the gel network have been monitored from the intensity ratios of ice-like and liquid-like -OH stretching band of water Fourier transform infrared (FTIR) spectra. Analysis of the -OH stretching band showed the strengthening of hydrogen bonding of water molecules in the gel which tend to weaken with the subsequent addition of sodium sulfate. PMID:19193039

Singh, Tejwant; Meena, Ramavtar; Kumar, Arvind

2009-02-26

67

Positive Cooperative Mechanistic Binding of Proteins at Low Concentrations: A Comparison of poly (sodium N-undecanoyl sulfate) and Sodium Dodecyl Sulfate  

PubMed Central

The interactions of the negatively charged achiral molecular micelle, poly (sodium N-undecanoyl sulfate) (poly-SUS), with four different proteins using intrinsic and extrinsic fluorescence spectroscopic probes, are studied. A comparison of poly-SUS with the conventional surfactant, sodium dodecyl sulfate (SDS), and the monomeric species, SUS, is also reported. In this work, we observed that poly-SUS preferentially binds to acidic proteins, exhibiting positive cooperativity at concentrations less than 1 mM for all proteins studied. Moreover, it appears that the hydrophobic microdomain formed through polymerization of the terminal vinyl group of the monomer, SUS, is largely responsible for the superior binding capacity of poly-SUS. From these results, we conclude that the interactions of poly-SUS with the acidic proteins are predominantly hydrophobic and postulate that poly-SUS would produce superior interactions relative to SDS at low concentrations in polyacrylamide gel electrophoresis (PAGE). As predicted, use of poly-SUS allowed separation of the His-tagged tumor suppressor protein, p53, at sample buffer concentrations as low as 0.08% w/v (2.9 mM), which is 24 times lower than required for SDS in the standard reducing PAGE protocol. This work highlights the use of poly-SUS as an effective surfactant in 1D biochemical analysis. PMID:21855885

Das, Susmita; Sylvain, Monica R.; Fernand, Vivian E.; Losso, Jack N.; El-Zahab, Bilal; Warner, Isiah M.

2011-01-01

68

Reactions in microemulsion formed by sodium dodecyl sulfate, water, and hexanol  

SciTech Connect

The reactions, oxidation of iodide by persulfate and basic hydrolysis of crystal violet, were investigated in the w/o microemulsion formed by sodium dodecyl sulfate, water, and hexanol. The second order rate constants were measured as a function of emulsion formed by sodium dodecyl sulfate, water, and hexanol. The second order rate constants were measured as a function of water to surfactant molar ratio and hexanol content. The increased rates were attributed to the smaller droplet size of the water pools. The rates are shown to be controlled by the water content as well as the hexanol content. It is shown that the manner in which the rate is affected applies to the catalyzed as well as the retarded reactions. This system is shown to be more effective than the AOT/water/decane system.

Valaulikar, B.S. (Bhabha Atomic Research Centre, Bombay (India). Chemistry Div.)

1993-11-01

69

Specific staining of sialic acid components on sodium dodecyl sulfate polyacrylamide gel.  

PubMed

Specific staining of sialic acid components after sodium dodecyl sulfate polyacrylamide gel electrophoresis can be carried out as follows: 1) extract glycoprotein of erythrocyte membranes or serum by the phenol-saline method, 2) electrophorese the extract on 5% polyacrylamide gel containing 0.1% sodium dodecyl sulfate at constant current, 3) treat the gel with chilled 0.04 M HIO4 for 45 minutes, 4) replace the periodic acid solution with one containing resorcinol 0.6 g, conc. HCl 50 ml, 0.1 M CuSO4 0.5 ml and H2O 50 ml, 5) warm the container in boiling water until blue violet sialic acid bands become clear, 6) replace the staining solution with a mixture of equal parts water and concentrated HCl and observe at once. PMID:6166103

Umezu, C; Yoshioka, N; Takahashi, K

1981-03-01

70

Effects of Proteoglycan on Dextran Sulfate Sodium-Induced Experimental Colitis in Rats  

Microsoft Academic Search

Proteoglycans (PG) are macromolecules composed of glycosaminoglycan chains covalently attached to a protein core. In this\\u000a study, we examined the effects of PG on dextran sulfate sodium (DSS)-induced experimental colitis in rats. First, to examine\\u000a whether PG may ameliorate acute established DSS colitis, PG was administered orally for 5 days to the model animals. We evaluated\\u000a the effects of PG on

Sakae Ota; Shuichi Yoshihara; Keinosuke Ishido; Masanori Tanaka; Keiichi Takagaki; Mutsuo Sasaki

2008-01-01

71

Healing Impairment Effect of Cyclooxygenase Inhibitors on Dextran Sulfate Sodium-Induced Colitis in Rats  

Microsoft Academic Search

We examined the effects of various cyclooxygenase (COX) inhibitors on the healing of colonic lesions induced by dextran sulfate sodium (DSS) in the rat. Colonic lesions were induced by 2.5% DSS in the drinking water for 7 days, and then the animals were fed with tap water for subsequent 7 days. Indomethacin (a nonselective COX inhibitor), SC-560 (a selective COX-1

Ryoichi Tsubouchi; Shusaku Hayashi; Yoko Aoi; Hikaru Nishio; Shun Terashima; Shinichi Kato; Koji Takeuchi

2006-01-01

72

Surface characterization of polyelectrolyte complex membranes based on sodium cellulose sulfate and various cationic components  

Microsoft Academic Search

Polyelectrolyte complex membranes based on sodium cellulose sulfate as a polyanion and various types of cationic components - poly(dimethyldiallylammonium chloride), poly(ethyleneimine hydrochloride) as polycations; or (2-(N-undecylamidocarbonyl)-ethyl)-dimethylbenzyl ammonium chloride, N-dodecylpyridinium chloride as cationic surfactants - were prepared. The membrane performances and selectivities in two pervaporation processes were tested. Results are discussed with respect to the surface characteristics of membranes, obtained from

Jaromír Lukáš; Klaus Richau; Hans-Hartmut Schwarz; Dieter Paul

1997-01-01

73

Micellization and synergistic interaction of binary surfactant mixtures based on sodium nonylphenol polyoxyethylene ether sulfate.  

PubMed

Mixed micelle formation and synergistic interactions of binary surfactant combinations of sodium nonylphenol polyoxyethylene ether sulfate (NPES) with typical surfactants such as sodium dodecyl sulfate (SDS), Triton X-100 (TX100), cetyl trimethyl ammonium bromide (CTAB), and sodium bis(2-ethylhexyl) sulfosuccinate (AOT) at 25 degrees C in the presence of NaCl have been investigated. The critical micelle concentration of the binary mixtures has been quantitatively estimated by steady-state fluorescence measurements. The micellar characteristics such as composition, activity coefficients, and mutual interaction parameters have been estimated following different theoretical treatments. Investigation on the micellization and synergistic interaction of NPES with four kinds of surfactants showed that the behavior of the binary mixture deviated from the ideal state. The analysis revealed that the interaction parameter values (beta) varied with variation of solvent composition. Besides the strong electrostatic attraction between the oppositely charged surfactant NPES-CTAB mixture, the interaction between NPES and SDS also showed far more deviation from ideal behavior than that of TX100 and AOT. The reason for the synergism is also discussed and the results show that an ionic and a nonionic surfactant character existed concurrently in NPES due to the combination of a sulfate group and polyoxyethylene as a hydrophilic moiety. Zeta potential and diffusion coefficient measurements of micelles confirmed the synergistic interaction between the binary surfactants. PMID:18005979

Chen, Zhong-Xiu; Deng, Shao-Ping; Li, Xiao-Kui

2008-02-15

74

Stopped-flow kinetic studies of sphere-to-rod transitions of sodium alkyl sulfate micelles induced by hydrotropic salt  

Microsoft Academic Search

The kinetics and mechanism of sphere-to-rod transitions of sodium alkyl sulfate micelles induced by hydrotropic salt, p-toluidine hydrochloride (PTHC), were investigated by stopped-flow with light scattering detection. Spherical sodium dodecyl sulfate (SDS) micelles transform into short ellipsoidal shapes at low salt concentrations ([PTHC]\\/[SDS], ?PTHC=0.3 and 0.4). Upon stopped-flow mixing aqueous solutions of spherical SDS micelles with PTHC, the scattered light

Jingyan Zhang; Zhishen Ge; Xiaoze Jiang; P. A. Hassan; Shiyong Liu

2007-01-01

75

Sulfonates as Terminal Electron Acceptors for Growth of Sulfite-Reducing Bacteria (Desulfitobacterium spp.) and Sulfate-Reducing Bacteria: Effects of Inhibitors of Sulfidogenesis  

PubMed Central

This study demonstrates the ability of Desulfitobacterium spp. to utilize aliphatic sulfonates as terminal electron acceptors (TEA) for growth. Isethionate (2-hydroxyethanesulfonate) reduction by Desulfitobacterium hafniense resulted in acetate as well as sulfide accumulation in accordance with the expectation that the carbon portion of isethionate was oxidized to acetate and the sulfur was reduced to sulfide. The presence of a polypeptide, approximately 97 kDa, was evident in isethionate-grown cells of Desulfitobacterium hafniense, Desulfitobacterium sp. strain PCE 1, and the two sulfate-reducing bacteria (SRB)—Desulfovibrio desulfuricans IC1 (T. J. Lie, J. R. Leadbetter, and E. R. Leadbetter, Geomicrobiol. J. 15:135–149, 1998) and Desulfomicrobium norvegicum; this polypeptide was not detected when these bacteria were grown on TEA other than isethionate, suggesting involvement in its metabolism. The sulfate analogs molybdate and tungstate, effective in inhibiting sulfate reduction by SRB, were examined for their effects on sulfonate reduction. Molybdate effectively inhibited sulfonate reduction by strain IC1 and selectively inhibited isethionate (but not cysteate) reduction by Desulfitobacterium dehalogenans and Desulfitobacterium sp. strain PCE 1. Desulfitobacterium hafniense, however, grew with both isethionate and cysteate in the presence of molybdate. In contrast, tungstate only partially inhibited sulfonate reduction by both SRB and Desulfitobacterium spp. Similarly, another inhibitor of sulfate reduction, 1,8-dihydroxyanthraquinone, effectively inhibited sulfate reduction by SRB but only partially inhibited sulfonate reduction by both SRB and Desulfitobacterium hafniense. PMID:10508097

Lie, Thomas J.; Godchaux, Walter; Leadbetter, Edward R.

1999-01-01

76

Hydrothermal synthesis of sodium tungstate nanorods and nanobundles in the presence of sodium sulfate  

SciTech Connect

Sodium tungstate nanorods and nanobundles have been successfully prepared, for the first time, through a simple salt-assisted hydrothermal route based on the reaction between Na{sub 2}WO{sub 4} and HCl in aqueous solution. The resultant sodium tungstate nanorods and nanobundles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and selected area electronic diffraction (SAED) techniques. The ingredients of the sample have been detected by energy-dispersive spectrum (EDS) method. It is found that hydrothermal temperature and time play important roles in the control of the morphology and size of the products.

Cao Guangxiang [Department of Chemistry and Chemical Engineering, Shandong University, 27 Shanda South Road, Jinan 250100 (China); Song Xinyu [Department of Chemistry and Chemical Engineering, Shandong University, 27 Shanda South Road, Jinan 250100 (China); Yu Haiyun [Department of Chemistry and Chemical Engineering, Shandong University, 27 Shanda South Road, Jinan 250100 (China); Fan Chunhua [Department of Chemistry and Chemical Engineering, Shandong University, 27 Shanda South Road, Jinan 250100 (China); Yin Zhilei [Department of Chemistry and Chemical Engineering, Shandong University, 27 Shanda South Road, Jinan 250100 (China); Sun Sixiu [Department of Chemistry and Chemical Engineering, Shandong University, 27 Shanda South Road, Jinan 250100 (China)]. E-mail: ssx@sdu.edu.cn

2006-02-02

77

Structure-based Alteration of Substrate Specificity and Catalytic Activity of Sulfite Oxidase from Sulfite Oxidation to Nitrate Reduction†  

PubMed Central

Eukaryotic sulfite oxidase is a dimeric protein that contains the molybdenum cofactor and catalyzes the metabolically essential conversion of sulfite to sulfate as the terminal step in the metabolism of cysteine and methionine. Nitrate Reductase is an evolutionally related molybdoprotein in lower organisms that is essential for growth on nitrate. In this study we describe human and chicken sulfite oxidase variants in which the active site has been modified to alter substrate specificity and activity from sulfite oxidation to nitrate reduction. Based on sequence alignments and the known crystal structure of chicken sulfite oxidase two residues are conserved in nitrate reductases that align with residues in the active site of sulfite oxidase. Based on the crystal structure of yeast nitrate reductase, both positions were mutated in human sulfite oxidase and chicken sulfite oxidase. The resulting double mutant variants demonstrated a marked decrease in sulfite oxidase activity but gained nitrate reductase activity. An additional methionine residue in the active site was proposed to be important in nitrate catalysis, and therefore the triple variant was also produced. The nitrate-reducing ability of the human sulfite oxidase triple mutant was nearly three-fold higher than that of the double mutant. In order to obtain detailed structural data on the active site of these variants, the analogous mutations in chicken sulfite oxidase were generated in order to perform crystallographic analysis. The crystal structures of the Mo domains of the double and triple mutants were solved to 2.4 Å and 2.1Å resolution, respectively. PMID:22263579

Qiu, James A.; Wilson, Heather L.; Rajagopalan, K.V.

2012-01-01

78

Influence and hydrolysis kinetics in titanyl sulfate solution from the sodium hydroxide molten salt method  

NASA Astrophysics Data System (ADS)

Hydrated titanium dioxide (HTD) was precipitated by thermal hydrolysis in purified titanyl sulfate solution (TSS) obtained through the sodium hydroxide molten salt clean method. Various factors including the stirring speed and initial concentrations of TiOSO4, sulfuric acid, and sodium ion were studied. The main influence factors in the hydrolysis process were the initial concentrations of TiOSO4 and sulfuric acid. Contrary to the ferrous ion, the sodium ion improved the ionic activity of Ti4+, but did not decrease the crystal size. The Boltzman growth model (x=A2+(A1-A2)/{1+exp[(t-t0)/dt)]}, which focuses on two main parameters (CTiOSO4 and CH2SO4), fits the hydrolysis process well with R2>0.97. An increase in sulfuric acid concentration negatively affected the hydrolysis rates and the value of A2, while t0 increased. An increase in titanyl sulfate concentration directly reduced the hydrolysis rates and particle size of HTD, contrary to the trend for the value of t0. A simulation software called 1stopt was used to observe the relationship between Z (A1, A2, t0, dt) and a, b (CTiO2 and CH2SO4).

Wang, Weijing; Chen, Desheng; Chu, Jinglong; Li, Jie; Xue, Tianyan; Wang, Lina; Wang, Dong; Qi, Tao

2013-10-01

79

Oral sodium phosphate versus sulfate-free polyethylene glycol electrolyte lavage solution in outpatient preparation for colonoscopy: a prospective comparison  

Microsoft Academic Search

Background: Biochemical abnormalities induced by oral sodium phosphate and the risk of cardiac arrhythmias as potential sequelae have yet to be investigated. Methods: We studied 98 outpatients scheduled to undergo diagnostic colonoscopy and prospectively randomized them to receive oral sodium phosphate or sulfate-free polyethylene glycol electrolyte lavage solution (SF-PEG-ELS) as recommended by the manufacturers. Results: Forty-nine patients received sodium phosphate

Wendell K. Clarkston; Tony N. Tsen; David F. Dies; C. Lynn Schratz; Surender K. Vaswani; Preben Bjerregaard

1996-01-01

80

Purification and characterization of an inducible dissimilatory type sulfite reductase from Clostridium pasteurianum.  

PubMed

An inducible sulfite reductase was purified from Clostridium pasteurianum. The pH optimum of the enzyme is 7.5 in phosphate buffer. The molecular weight of the reductase was determined to be 83,600 from sodium dodecyl sulfate gel electrophoresis with a proposed molecular structure: alpha 2 beta 2. Its absorption spectrum showed a maximum at 275 nm, a broad shoulder at 370 nm and a very small absorption maximum at 585 nm. No siroheme chromophore was isolated from this reductase. The enzyme could reduce the following substrates in preferential order: NH2OH greater than SeO3 (2-) greater than NO(2-) 2 at rates 50% or less of its preferred substrate SO3(2-). The proposed dissimilatory intermediates, S3O6 (2-) or S2O3(2-), were not utilized by this reductase while KCN inhibited its activity. Varying the substrate concentration [SO3(2-)] from 1 to 2.5 mumol affected the stoichiometry of the enzyme reaction by alteration of the ratio of H2 uptake to S2- formed from 2.5:1 to 3.1:1. The inducible sulfite reductase was found to be linked to ferredoxin which could be completely replaced by methyl viologen or partially by benzyl viologen. Some of the above-mentioned enzyme properties and physiological considerations indicated that it was a dissimilatory type sulfite reductase. PMID:6742957

Harrison, G; Curle, C; Laishley, E J

1984-05-01

81

Conformational study of papain in the presence of sodium dodecyl sulfate in aqueous medium.  

PubMed

The interactions between a globular protein, papain and the anionic surfactant, sodium dodecyl sulfate (SDS) have been investigated in aqueous medium using fluorimetric, circular dichroism, Fourier transform infra-red, UV-vis spectrophotometric, dynamic light scattering, and nuclear magnetic resonance techniques. The conformational change of papain in aqueous solution has been studied in the presence of SDS. The results show the high alpha-helical content and unfolded structure of papain in the presence of SDS due to strong electrostatic repulsion leading to a "necklace and bead model" in protein-surfactant complexes. PMID:15737549

Ghosh, Soumen

2005-03-25

82

Adsorption of sodium dodecyl sulfate on functionalized graphene measured by conductometric titration.  

PubMed

We report on the adsorption of sodium dodecyl sulfate (SDS) onto functionalized graphene sheets (FGSs) in an aqueous system, measured at broad SDS and FGS concentration ranges by conductometric surfactant titration. At dilute SDS concentrations (<12 ?M in bulk solution), there is evidence of a counterion exchange between hydronium ions (from the dissociation of acidic chemical functionalities on FGS) and sodium ions coadsorbing with dodecyl sulfate monomers onto FGSs. We find that, for FGS with a carbon-to-oxygen ratio of ~18, monolayer adsorption of SDS on FGS reaches full surface coverage by ~12 ?M SDS. Additionally, the critical surface aggregation concentration (csac) for surface micelle formation on FGS is measured to be ~1.5 mM SDS. The transition from monolayer adsorption to surface micelle formation appears to occur at a similar SDS concentration on FGSs as on graphite, suggesting there is little difference in the surfactant adsorption behavior on both materials. We estimate that the FGS surface area available for SDS adsorption is ~600 m(2)/g, which is significantly less than expected for FGSs in suspension and indicates the presence of regions on FGS on which SDS adsorption does not occur. PMID:23734569

Hsieh, Andrew G; Punckt, Christian; Korkut, Sibel; Aksay, Ilhan A

2013-07-01

83

Isolated sulfite oxidase deficiency.  

PubMed

Isolated sulfite oxidase (SO) deficiency is an autosomal recessively inherited inborn error of sulfur metabolism. In this report of a ninth patient the clinical history, laboratory results, neuropathological findings and a mutation in the sulfite oxidase gene are described. The data from this patient and previously published patients with isolated sulfite oxidase deficiency and molybdenum cofactor deficiency are summarized to characterize this rare disorder. The patient presented neonatally with intractable seizures and did not progress developmentally beyond the neonatal stage. Dislocated lenses were apparent at 2 months. There was increased urine excretion of sulfite and S-sulfocysteine and a decreased concentration of plasma cystine. A lactic acidemia was present for 6 months. Liver sulfite oxidase activity was not detectable but xanthine dehydrogenase activity was normal. The boy died of respiratory failure at 32 months. Neuropathological findings of cortical necrosis and extensive cavitating leukoencephalopathy were reminiscent of those seen in severe perinatal asphyxia suggesting an etiology of energy deficiency. A point mutation that resulted in a truncated protein missing the molybdenum-binding site has been identified. PMID:9050047

Rupar, C A; Gillett, J; Gordon, B A; Ramsay, D A; Johnson, J L; Garrett, R M; Rajagopalan, K V; Jung, J H; Bacheyie, G S; Sellers, A R

1996-12-01

84

Electrophoretic separation of alginic sodium diester and sodium hexametaphosphate in chondroitin sulfate that interfere with the cetylpyridinium chloride titration assay.  

PubMed

The most commonly used chondroitin sulfate (CS) assay method is cetylpyridinium chloride (CPC) titration. Cellulose acetate membrane electrophoresis (CAME) is the technique used for detection of impurities in the U.S. Pharmacopeia's CS monograph. Because CPC titration is a relatively nonspecific quantitative technique, the apparent amount of CS as determined by CPC titration alone may not reflect the true amount of CS due to possible interference with the CPC assay by impurities that contain CPC titratable functional groups. When CAME is used in conjunction with CPC titration, certain non-CS and adulterants can be visualized and estimated, and a true value for CS can be assigned once the presence of these non-CS impurities has been ruled out. This study examines conjunct application of CPC and CAME in ascertaining CS assay and purity in the presence of certain adulterants. These include propylene glycol alginate sulfate sodium, known in commerce as alginic sodium diester (ASD), and Zero One (Z1), a water-soluble agent newly reported in the CS marketplace and subsequently identified as sodium hexametaphosphate. ASD, Z1, and CS are similar in physical appearance and solubility in water and ethanol. They are also titratable anions and form ionic pairs with CPC, therefore interfering with the CPC titration assay for CS CAME separates these adulterants from each other and from CS by differences in their electrophoretic mobility. CAME is able to detect these impurities in CS at levels as low as 0.66% by weight. Although it is recommended that a method for detecting impurities (e.g., CAME) be used in cormbination with relatively nonspecific assay methods such as CPC titration, this is seldom done in practice. Assay results for CS derived fromn CPC titration may, therefore, be misleading, leaving the CS supply chain vulnerable to adulteration. In this study, the authors investigated ASD and Z1 adulteration of CS and developed an electrophoretic separation of these adulterants in CS and procedures to isolate ASD from CS matrixes containing these adulterants. The authors describe in this paper utilization of an orthogonal approach to establish the identity of Z1 as sodium hexametaphosphate and to confirm the identity of ASD, including ethanol fractionation, FTIR spectroscopy, differential scanning calorimetry, and NMR spectroscopy. The authors suggest that CAME is a cost-effective and easy to use methodfor detecting certain impurities in CS raw ingredients and recommend that CPC and CAME be used in combination by QC laboratories as a means of effectively deterring the practice of adulterating CS raw materials with the known adulterants ASD and Z1 and/or other non-chondroitin substances that can be separated from CSby CAME and that exhibit CPC titration behavior similar to CS. PMID:25372663

Weiguo, Zhang; Giancaspro, Gabriel; Adams, Kristie M; Neal-Kababick, James; Hildreth, Jana; Li, Aishan; Roman, Mark C; Betz, Joseph M

2014-01-01

85

In vitro effects of dextran sulfate sodium on a Caco-2 cell line and plausible mechanisms for dextran sulfate sodium-induced colitis.  

PubMed

Pathogenic mechanisms responsible for inflammatory bowel disease (IBD) are poorly understood. In an IBD animal model, the oral administration of polysaccharides such as dextran sulfate sodium (DSS) induces colitis, which exhibit several clinical and histological features for IBD. However, pathogenic factors in the development of colitis remain unclear. Therefore, we investigated possible mechanisms for DSS-induced colitis, and mainly focused on biological responses from an intestinal epithelial cell line, Caco-2. Cytotoxicity and cytokine release were measured using MTS assays and ELISA, respectively. The effect of DSS on the transepithelial electrical resistance (TEER) of Caco-2 cell monolayers was also evaluated. Cell cycle progression was estimated using antibodies directed against p53 and cdc-2 proteins. The generation of reactive oxygen species (ROS) was measured using a DCFH-DA method. Pyridylamino-DSS (PA-DSS) was used as a fluorometric label in order to investigate fluorescence-microscopically the location of DSS in Caco-2 cells. DSS induced cytotoxicity on Caco-2 cells at 5%. DSS also induced strong TEER decrease at 3%. DSS induced the weak release of IL-8, IL-6, and TGF-beta1. Remarkably DSS arrested Caco-2 cell cycle and reduced the intracellular generation of ROS. Under fluorescence microscopy, PA-DSS entered cells and bound to the nucleus, indicating this binding of DSS may be involved in the cell cycle arrest of Caco-2 cells. The cell cycle arrest and reduced intracellular generation of ROS may be involved during initiation or throughout the early stages of DSS-induced colitis. PMID:17089061

Araki, Yoshio; Sugihara, Hiroyuki; Hattori, Takanori

2006-12-01

86

Enzymes Induced in a Bacterium by Growth on Sodium Dodecyl Sulfate  

PubMed Central

Alkyl sulfatase was induced by growth on nutrient broth plus sodium dodecyl sulfate (SDS) in a bacterium we have designated Pseudomonas C12B. Measurement of the radioactivity of S35O4= released from SDS35 by the enzyme in cell-free extracts provided an effective assay technique. The barium chloranilate assay for release of SO4= from SDS was somewhat less sensitive but effective if analyzed at 332 m?. This test was only approximately 55% as sensitive if analyzed at 530 m?. The activity of the glyoxylate bypass enzymes, isocitrate lyase and malate synthetase, was significantly stimulated by growth of the bacteria on SDS as the sole carbon source, but not by growth on nutrient broth or nutrient broth plus SDS. PMID:14201090

Williams, Joy; Payne, W. J.

1964-01-01

87

High energy ultracapacitor based on carbon xerogel electrodes and sodium sulfate electrolyte  

NASA Astrophysics Data System (ADS)

An ultracapacitor (UCap) based on carbon xerogel electrodes and sodium sulfate electrolyte was investigated in the voltage range between 0 and 1.8 V. Notwithstanding the high value of maximum voltage (1.8 V) the UCap exhibited excellent stability during 20000 of cycling test. Moreover, the achievement of this high voltage made possible to obtain high value of specific energy. The stability was possible because the potential limits of electrode-electrolyte decomposition at positive and negative electrodes were never achieved. This is because an asymmetric UCap with different amounts of carbon xerogel in the electrodes was used. The UCap with the carbon xerogel of BET specific surface area of 3100 m2 g-1 demonstrated a specific energy of 17.5 Wh kg-1 and a specific capacitance of 156 F g-1 and, retained 91% of initial capacitance after 20000 cycles of duration test.

Staiti, P.; Arenillas, A.; Lufrano, F.; Menéndez, J. Á.

2012-09-01

88

Adsorption of Sodium Dodecyl Sulfate on Ge Substrate: The Effect of a Low-Polarity Solvent  

PubMed Central

This paper describes the adsorption of sodium dodecyl sulfate (SDS) molecules in a low polar solvent on Ge substrate by using Fourier transform infrared-attenuated total reflection (FTIR-ATR) spectroscopy and atomic force microscopy (AFM). The maximum SDS amount adsorbed is (5.0 ± 0.3) × 1014 molecules cm?2 in CHCl3, while with the use of CCl4 as subphase the ability of SDS adsorbed is 48% lower. AFM images show that depositions are highly disordered over the interface, and it was possible to establish that the size of the SDS deposition is around 30–40 nm over the Ge surface. A complete description of the infrared spectroscopic bands for the head and tail groups in the SDS molecule is also provided. PMID:22942685

Viana, Rommel B.; da Silva, Albérico B. F.; Pimentel, André S.

2012-01-01

89

Inhibition effects of inorganic multivalent cations on iron corrosion in aerated sodium sulfate solution  

SciTech Connect

Inhibition effects of inorganic multivalent cations on corrosion of Fe in an aerated 0.5 M sodium sulfate (Na{sub 2}So{sub 4}) solution were investigated using polarization measurements. The cations formed deposit layers of their hydroxides on the Fe surface by reactions with hydroxide ions (OH{sup {minus}}) afforded through the cathodic process of Fe corrosion. Some layers on the surface were analyzed by x-ray photoelectron spectroscopy (XPS) and electron probe microanalysis (EPMA). Since the cations suppressed the cathodic process but stimulated the anodic one, their inhibition efficiencies were not markedly high. Inhibition effects of the cations on the cathodic process were related closely to the hard and soft acids and bases (HSAB) principle because the effect increased with the hardness of a cation as an acid.

Aramaki, K. [Keio Univ., Hiyoshi, Yokomama (Japan). Faculty of Science and Technology

1999-02-01

90

Renaturation of enzymes after polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate  

SciTech Connect

A number of enzymes, including amylases, dehydrogenases, and proteases, were shown to be renaturable after polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. Enzyme activity was detected in situ by action on substrates introduced into the gel and subsequent staining of either the product or unreacted substrate. Enzymes appeared to recover activity as soon as the detergent diffused out of the gel. Renatured enzymes were retained in gels after electrophoresis longer than native enzymes which had been subjected to electrophoresis in the absence of detergent. Re-electrophoresis of the renatured enzymes showed that part of the retained activity was physically anchored to the gel, possibly by the folding of polypeptides around the gel matrix as the enzymes were renatured.

Lacks, S.A.; Springhorn, S.S.

1980-08-10

91

Toxicity detection of sodium nitrite, borax and aluminum potassium sulfate using electrochemical method.  

PubMed

Based on the inhibition effect on the respiratory chain activity of microorganisms by toxicants, an electrochemical method has been developed to measure the current variation of a mediator in the presence of microorganisms contacted with a toxicant. Microelectrode arrays were adopted in this study, which can accelerate the mass transfer rate of an analyte to the electrode and also increase the total current signal, resulting in an improvement in detection sensitivity. We selected Escherichia coli as the testee and the standard glucose-glutamic acid as an exogenous material. Under oxygen restriction, the experiments in the presence of toxicant were performed at optimum conditions (solution pH 7.0, 37 degrees C and reaction for 3 hr). The resulting solution was then separated from the suspended microorganisms and was measured by an electrochemical method, using ferricyanide as a mediator. The current signal obtained represents the reoxidation of ferrocyanide, which was transformed to inhibiting efficiency, IC50, as a quantitative measure of toxicity. The IC50 values measured were 410, 570 and 830 mg/L for sodium nitrite, borax and aluminum potassium sulfate, respectively. The results show that the toxicity sequence for these three food additives is consistent with the value reported by other methods. Furthermore, the order of damage degree to the microorganism was also observed to be: sodium nitrite > borax > aluminum potassium sulfate > blank, according to the atomic force microscopy images of E. coli after being incubated for 3 hr with the toxic compound in buffer solutions. The electrochemical method is expected to be a sensitive and simple alternative to toxicity screening for chemical food additives. PMID:23923788

Yu, Dengbin; Yong, Daming; Dong, Shaojun

2013-04-01

92

Preparation, characterization and pharmacokinetics of fluorescence labeled propylene glycol alginate sodium sulfate  

NASA Astrophysics Data System (ADS)

A rapid and sensitive fluorescence labeling method was developed and validated for the microanalysis of a sulfated polysaccharide drug,namely propylene glycol alginate sodium sulfate (PSS), in rat plasma. Fluorescein isothiocyanate (FITC) was selected to label PSS, and 1, 6-diaminohexane was used to link PSS and FITC in order to prepare FITC-labeled PSS (F-PSS) through a reductive amination reaction. F-PSS was identified by UV-Vis, FT-IR and 1H-NMR spectrum. The cell stability and cytotoxicity of F-PSS were tested in Madin-Darby canine kidney (MDCK) cells. The results indicated that the labeling efficiency of F-PSS was 0.522% ± 0.0248% and the absolute bioavailability was 8.39%. F-PSS was stable in MDCK cells without obvious cytotoxicity. The method was sensitive and reliable; it showed a good linearity, precision, recovery and stability. The FITC labeling method can be applied to investigating the absorption and metabolism of PSS and other polysaccharides in biological samples.

Li, Pengli; Li, Chunxia; Xue, Yiting; Zhang, Yang; Liu, Hongbing; Zhao, Xia; Yu, Guangli; Guan, Huashi

2014-08-01

93

Effect of Long Chain Alcohols on Micellar Relaxation Time and Foaming Properties of Sodium Dodecyl Sulfate Solutions  

Microsoft Academic Search

The effect of long chain alcohols (5 mol% CnOH forn= 8, 10, 12, 14, and 16) on the micellar stability of sodium dodecyl sulfate (SDS) solutions (SDS concentration ranging from 25 to 200 mM) was investigated and related to foaming properties, such as foamability, dynamic and equilibrium surface tension, and surface viscosity. The slow micellar relaxation time ?2, which is

Alexander Patist; Teri Axelberd; Dinesh O. Shah

1998-01-01

94

Modification of an acetone-sodium dodecyl sulfate disruption method for cellular protein extraction from neuropathogenic Clostridium botulinum  

Technology Transfer Automated Retrieval System (TEKTRAN)

An acetone-sodium dodecyl sulfate (SDS) disruption method was used for the extraction of cellular proteins from neurotoxigenic Clostridium botulinum. The amount of protein extracted per gram of dry weight and the protein profile as revealed by polyacrylamide gel electrophoresis (PAGE) was comparabl...

95

Small angle neutron scattering study of sodium dodecyl sulfate micellar growth driven by addition of a hydrotropic salt  

Microsoft Academic Search

The structures of aggregates formed in aqueous solutions of an anionic surfactant, sodium dodecyl sulfate (SDS), with the addition of a cationic hydrotropic salt, p-toluidine hydrochloride (PTHC), have been investigated by small angle neutron scattering (SANS). The SANS spectra exhibit a pronounced peak at low salt concentration, indicating the presence of repulsive intermicellar interactions. Model-independent real space information about the

P. A Hassan; Gerhard Fritz; Eric W Kaler

2003-01-01

96

Use of a Ferrous Sulfate - Sodium Dithionite Blend to Treat a Dissolved Phase Cr(VI) Plume  

EPA Science Inventory

A field study was conducted to evaluate the use of a combination of sodium dithionite and ferrous sulfate in creating an in situ redox zone for treatment of a dissolved phase Cr(VI) plume at a former industrial site. The reductant blend was injected into the path of a dissolved ...

97

Characterization of implant materials in fetal bovine serum and sodium sulfate by electrochemical impedance spectroscopy. II. Coarsely sandblasted samples.  

PubMed

Electrochemical impedance spectroscopy is used to investigate the corrosion resistance of coarsely sandblasted implant alloys, commercially pure titanium, Ti6Al4V, Ti6Al7Nb, and CoCrMo in 0.1M sodium sulfate and fetal bovine serum. Coarsely sandblasted samples have a heterogeneous surface constituted by a large number of protrusions and recessions. Impedance spectra collected in sodium sulfate present two time constants (maxima in the phase-angle of the bode plot) associated with the total surface and with the tips, respectively. In bovine serum, the two maxima in the impedance spectra cannot be distinguished because of the formation of an adsorption layer of organic molecules, which causes a decrease in the values of both the total and tips' capacitances as well as an increase in the polarization resistance. Ti6Al4V and Ti6Al7Nb show the highest corrosion rate both in serum and in sodium sulfate. Based on the capacitance values obtained in sodium sulfate, the real surface area of the coarsely sandblasted electrodes has been estimated relative to mechanically polished surfaces. The values of the effective electrode area correlate with the mechanical properties of the samples: in fact, the softest electrode (commercially pure titanium) shows the largest effective electrode area, whereas the hardest material (CoCrMo alloy) shows the smallest surface area. PMID:14517883

Contu, F; Elsener, B; Böhni, H

2003-10-01

98

Effect of potassium sodium tartrate and sodium citrate on the preparation of {alpha}-calcium sulfate hemihydrate from flue gas desulfurization gypsum in a concentrated electrolyte solution  

SciTech Connect

Flue gas desulfurization (FGD) gypsum mainly composed of calcium sulfate dihydrate (DH) was used as a raw material to obtain alpha-calcium sulfate hemihydrate ({alpha}-HH) through dehydration in a Ca-Mg-K-Cl-solution medium at 95{sup o}C under atmospheric pressure. The effects of potassium sodium tartrate and sodium citrate on the preparation of alpha-HH in the electrolyte solution were investigated. The results revealed that the addition of potassium sodium tartrate (1.0 x 10{sup -2} - 2.5 x 10{sup -2}M) decreased the dehydration rate of FGD gypsum and increased the length/width (l/w) ratio of {alpha}-HH crystals, which could yield unfavorable strength properties. Addition of sodium citrate (1.0 x 10{sup -5} - 2.0 x 10{sup -5}M) slightly increased the dehydration rate of FGD gypsum and decreased the l/w ratio of {alpha}-HH crystals, which could be beneficial to increase strength. However, it also led to a partial formation of anhydrite (AH) crystals. AH was also the only dehydration product when the concentration of sodium citrate increased to 1.0 x 10{sup -4}M. Therefore, sodium citrate rather than potassium sodium tartrate could be used as an additive in Ca-Mg-K-Cl electrolyte solutions if alpha-HH with a shorter l/w ratio is the desired product from FGD gypsum dehydration. The concentration of sodium citrate should be properly controlled to reduce the formation of AH.

Shen, Z.X.; Guan, B.H.; Fu, H.L.; Yang, L.C. [Zhejiang University, Hangzhou (China). Dept. of Environmental Engineering

2009-12-15

99

Enoxaparin improves the course of dextran sodium sulfate-induced colitis in syndecan-1-deficient mice.  

PubMed

Syndecan-1 (Sdc1) plays a major role in wound healing and modulates inflammatory responses. Sdc1 expression is reduced in lesions of patients with ulcerative colitis. The aim of this study was to investigate the role of Sdc1 in murine dextran sodium sulfate (DSS)-induced colitis. DSS colitis was induced in Sdc1-deficient (knockout (KO)) and wild-type mice by oral administration of 3% DSS. KO mice exhibited a significantly increased lethality as compared with wild-type controls (61 versus 5%, P < 0.05). Impaired mucosal healing and prolonged recruitment of inflammatory cells in KO mice were accompanied by significant up-regulation of tumor necrosis factor-alpha, CC chemokine ligand 3/macrophage inflammatory protein-1alpha, and vascular cell adhesion molecule-1, as determined by histological correlation between 0 and 15 days after colitis induction, TaqMan low-density array analysis, and quantitative real-time PCR. Treatment from days 7 through 14 with enoxaparin, a functional analogue of the Sdc1 heparan sulfate chains, significantly reduced lethality of KO mice due to DSS-induced colitis, which was correlated with improved mucosal healing. In vitro, Sdc1-deficient polymorphonuclear cells displayed increased adhesion to endothelial cells and intercellular adhesion molecule-1, and enoxaparin reverted adhesion to wild-type levels. Small interfering RNA-mediated knockdown of Sdc1 expression resulted in reduced basic fibroblast growth factor-mediated mitogen-activated protein kinase signaling and reduced Caco-2 cell proliferation. We conclude that Sdc1 has a protective effect during experimental colitis. The modification of missing Sdc1 function by heparin analogues may emerge as a promising anti-inflammatory approach. PMID:20008145

Floer, Martin; Götte, Martin; Wild, Martin K; Heidemann, Jan; Gassar, Ezeddin Salem; Domschke, Wolfram; Kiesel, Ludwig; Luegering, Andreas; Kucharzik, Torsten

2010-01-01

100

40 CFR Appendix A to Subpart Hhhh... - Method for Determining Free-Formaldehyde in Urea-Formaldehyde Resins by Sodium Sulfite (Iced...  

Code of Federal Regulations, 2010 CFR

...8Disposable pipettes. 2.1.9Several 5-ounce (oz.) plastic cups. 2.1.10Ice cube trays (small cubes). 2.2Materials Required. 2.2.1Ice cubes (made with distilled water). 2.2.2A solution of 1 molar (M) sodium...

2010-07-01

101

40 CFR Appendix A to Subpart Hhhh... - Method for Determining Free-Formaldehyde in Urea-Formaldehyde Resins by Sodium Sulfite (Iced...  

Code of Federal Regulations, 2013 CFR

...8Disposable pipettes. 2.1.9Several 5-ounce (oz.) plastic cups. 2.1.10Ice cube trays (small cubes). 2.2Materials Required. 2.2.1Ice cubes (made with distilled water). 2.2.2A solution of 1 molar (M) sodium...

2013-07-01

102

40 CFR Appendix A to Subpart Hhhh... - Method for Determining Free-Formaldehyde in Urea-Formaldehyde Resins by Sodium Sulfite (Iced...  

Code of Federal Regulations, 2012 CFR

...8Disposable pipettes. 2.1.9Several 5-ounce (oz.) plastic cups. 2.1.10Ice cube trays (small cubes). 2.2Materials Required. 2.2.1Ice cubes (made with distilled water). 2.2.2A solution of 1 molar (M) sodium...

2012-07-01

103

40 CFR Appendix A to Subpart Hhhh... - Method for Determining Free-Formaldehyde in Urea-Formaldehyde Resins by Sodium Sulfite (Iced...  

Code of Federal Regulations, 2011 CFR

...8Disposable pipettes. 2.1.9Several 5-ounce (oz.) plastic cups. 2.1.10Ice cube trays (small cubes). 2.2Materials Required. 2.2.1Ice cubes (made with distilled water). 2.2.2A solution of 1 molar (M) sodium...

2011-07-01

104

40 CFR Appendix A to Subpart Hhhh... - Method for Determining Free-Formaldehyde in Urea-Formaldehyde Resins by Sodium Sulfite (Iced...  

...8Disposable pipettes. 2.1.9Several 5-ounce (oz.) plastic cups. 2.1.10Ice cube trays (small cubes). 2.2Materials Required. 2.2.1Ice cubes (made with distilled water). 2.2.2A solution of 1 molar (M) sodium...

2014-07-01

105

Mechanism for stabilization of the molten globule state of papain by sodium n-alkyl sulfates: spectroscopic and calorimetric approaches.  

PubMed

Papain exists in a molten globule (MG) state at pH 2 and in this state protein tends to aggregate in the presence of lower concentrations of guanidine hydrochloride (GuHCl). Such aggregation is prevented if low concentrations of sodium n-alkyl sulfates are also present in the buffer; in addition, stabilization of the protein is also induced. The guanidine hydrochloride and temperature-induced unfolding of papain, in the presence of n-alkyl sulfates, indicate stabilization of the protein as seen from the higher transition midpoints when monitored by fluorescence, circular dichroism, and differential scanning calorimetry. However, a similar phenomenon is not seen under neutral conditions in the presence of n-alkyl sulfate concentrations. The effect of n-alkyl sulfates on the structure of the MG state of papain was utilized to investigate the contribution of hydrophobic interaction to the stability of the MG state. The Td values of the MG states of papain in the presence of n-alkyl sulfates at different concentrations showed substantial variation. The enhancement of Td values at the stability criterion of MG states corresponded with increasing chain length of the cited n-alkyl sulfates. The present results suggest that the hydrophobic interactions play important roles in stabilizing and preventing the aggregation of the MG state of papain. PMID:18405913

Chamani, J; Heshmati, M

2008-06-01

106

Curcumin Inhibits STAT3 Signaling in the Colon of Dextran Sulfate Sodium-treated Mice  

PubMed Central

Turmeric (Curcuma longa L., Zingiberaceae) has a long history of use in medicine for the treatment of inflammatory conditions. One of the major constituents of turmeric is curcumin (diferuloylmethane), which is responsible for its characteristic yellow color. In the present study, we have examined the chemoprotective effects of curcuminon dextran sulfate sodium (DSS)-induced mouse colitis. For this purpose, we pre-treated male ICR mice with curcumin (0.1 or 0.25 mmol/kg in 0.05% carboxymethyl cellulose) by gavage for a week and then co-treated the animals with curcumin by gavage and 3% DSS in drinking water for another 7 days. Our study revealed that administration of curcumin significantly attenuated the severity of DSS-induced colitis and STAT3 signaling in mouse colon. The levels of the cell cycle regulators CDK4 and cylinD1 were significantly reduced by curcumin administration. Moreover, the expression of p53, which is an upstream regulator of the CDK4-cylinD1 complex, was inhibited by curcumin treatment. PMID:25337545

Yang, Joon-Yeop; Zhong, Xiancai; Yum, Hye-Won; Lee, Hyung-Jun; Kundu, Joydeb Kumar; Na, Hye-Kyung; Surh, Young-Joon

2013-01-01

107

Self-aggregation of sodium dodecyl sulfate within (choline chloride + urea) deep eutectic solvent.  

PubMed

Deep eutectic solvents (DESs) have shown tremendous promise as green solvents with low toxicity and cost. Understanding molecular aggregation processes within DESs will not only enhance the application potential of these solvents but also help alleviate some of the limitations associated with them. Among DESs, those comprising choline chloride and appropriate hydrogen-bond donors are inexpensive and easy to prepare. On the basis of fluorescence probe, electrical conductivity, and surface tension experiments, we present the first clear lines of evidence for self-aggregation of an anionic surfactant within a DES containing a small fraction of water. Namely, well-defined assemblies of sodium dodecyl sulfate (SDS) apparently form in the archetype DES Reline comprising a 1:2 molar mixture of choline chloride and urea. Significant enhancement in the solubility of organic solvents that are otherwise not miscible in choline chloride-based DESs is achieved within Reline in the presence of SDS. The remarkably improved solubility of cyclohexane within SDS-added Reline is attributed to the presence of spontaneously formed cyclohexane-in-Reline microemulsions by SDS under ambient conditions. Surface tension, dynamic light scattering (DLS), small-angle X-ray scattering (SAXS), density, and dynamic viscosity measurements along with responses from the fluorescence dipolarity and microfluidity probes of pyrene and 1,3-bis(1-pyrenyl)propane are employed to characterize these aggregates. Such water-free oil-in-DES microemulsions are appropriately sized to be considered as a new type of nanoreactor. PMID:25314953

Pal, Mahi; Rai, Rewa; Yadav, Anita; Khanna, Rajesh; Baker, Gary A; Pandey, Siddharth

2014-11-11

108

Sodium dodecyl sulfate-polyacrylamide gel protein electrophoresis of freshwater photosynthetic sulfur bacteria.  

PubMed

Sodium dodecyl sulfate-polyacrylamide gel protein electrophoresis (SDS-PAGE) was carried out using different bacterial strains of the photosynthetic sulfur bacteria Chlorobium, Thiocapsa, Thiocystis, and Chromatium cultured in the laboratory, and the natural blooms in two karstic lakes (Lake Cisó and Lake Vilar, NE Spain) where planktonic photosynthetic bacteria (purple and green sulfur bacteria) massively developed accounting for most of the microbial biomass. Several extraction, solubilization, and electrophoresis methods were tested to develop an optimal protocol for the best resolution of the SDS-PAGE. Protein composition from different water depths and at different times of the year was visualized within a molecular mass range between 100 and 15 kDa yielding up to 20 different protein bands. Protein banding patterns were reproducible and changed in time and with depth in agreement with changes in photosynthetic bacteria composition. When a taxonomically stable community was followed in time, differences were observed in the intensity but not in the composition of the SDS-PAGE banding pattern. Three environmental variables directly related to the activity of sulfur bacteria (light, oxygen, and sulfide concentrations) had a significant effect on protein banding patterns and explained 33% of the variance. Changes in natural protein profiles of the bacterial blooms agreed with changes in species composition and in the in situ metabolic state of the populations. PMID:20524118

Osuna, M Begoña; Casamayor, Emilio O

2011-01-01

109

Sodium dodecyl sulfate monomers induce XAO peptide polyproline II to ?-helix transition.  

PubMed

XAO peptide (Ac-X2A7O2-NH2; X: diaminobutyric acid side chain, -CH2CH2NH3(+); O: ornithine side chain, -CH2CH2CH2NH3(+)) in aqueous solution shows a predominantly polyproline II (PPII) conformation without any detectable ?-helix-like conformations. Here we demonstrate by using circular dichroism (CD), ultraviolet resonance Raman (UVRR) and nuclear magnetic resonance (NMR) spectroscopy that sodium dodecyl sulfate (SDS) monomers bind to XAO and induce formation of ?-helix-like conformations. The stoichiometry and the association constants of SDS and XAO were determined from the XAO-SDS diffusion coefficients measured by pulsed field gradient NMR. We developed a model for the formation of XAO-SDS aggregate ?-helix-like conformations. Using UVRR spectroscopy, we calculated the Ramachandran ? angle distributions of aggregated XAO peptides. We resolved ?-, ?- and 3(10)-helical conformations and a turn conformation. XAO nucleates SDS aggregation at SDS concentrations below the SDS critical micelle concentration. The XAO4-SDS16 aggregates have four SDS molecules bound to each XAO to neutralize the four side chain cationic charges. We propose that the SDS alkyl chains partition into a hydrophobic core to minimize the hydrophobic area exposed to water. Neutralization of the flanking XAO charges enables ?-helix formation. Four XAO-SDS4 aggregates form a complex with an SDS alkyl chain-dominated hydrophobic core and a more hydrophilic shell where one face of the ?-helix peptide contacts the water environment. PMID:25121643

Hong, Zhenmin; Damodaran, Krishnan; Asher, Sanford A

2014-09-11

110

Allyl Isothiocyanate Ameliorates Angiogenesis and Inflammation in Dextran Sulfate Sodium-Induced Acute Colitis  

PubMed Central

Allyl isothiocyanate (AITC) is a phytochemical found in cruciferous vegetables that has known chemopreventive and chemotherapeutic activities. Thus far, the antiangiogenic activity of AITC has not been reported in in vivo studies. Herein, we investigated the effect of AITC on angiogenesis and inflammation in a mouse model of colitis. Experimental colitis was induced in mice by administering 3% dextran sulfate sodium via drinking water. To monitor the activity of AITC in this model, we measured body weight, disease activity indices, histopathological scores, microvascular density, myeloperoxidase activity, F4/80 staining, inducible nitric oxide synthase (iNOS) expression, cyclooxygenase-2 (COX-2) expression, and vascular endothelial growth factor (VEGF)-A/VEGF receptor 2 (VEGFR2) expression in the mice. We found that AITC-treated mice showed less weight loss, fewer clinical signs of colitis, and longer colons than vehicle-treated mice. AITC treatment also significantly lessened the disruption of colonic architecture that is normally associated with colitis and repressed the microvascularization response. Further, AITC treatment reduced both leukocyte recruitment and macrophage infiltration into the inflamed colon, and the mechanism these activities involved repressing iNOS and COX-2 expression. Finally, AITC attenuated the expression of VEGF-A and VEGFR2. Thus, AITC may have potential application in treating conditions marked by inflammatory-driven angiogenesis and mucosal inflammation. PMID:25051185

Davaatseren, Munkhtugs; Hwang, Jin-Taek; Park, Jae Ho; Kim, Myung-Sunny; Wang, Shuaiyu; Sung, Mi Jeong

2014-01-01

111

Effect of Arctium lappa L. in the dextran sulfate sodium colitis mouse model  

PubMed Central

AIM: To analyze the possible protective role of Arctium lappa L. (AL) in a murine model of ulcerative colitis (UC). METHODS: BALB/c mice were administered 100 mg/kg AL powder orally each day. After 7 d, colitis was induced by administration of dextran sulfate sodium (DSS) (5% W/V) in drinking water for a further 8 consecutive days. Diarrhea and bloody stools as well as colonic histology were observed. The level of interleukin-6 (IL-6) and tumor necrosis factor-? (TNF-?) in colonic sections were detected by immunohistochemistry. RESULTS: There were significant differences in mean body weight values and disease activity indices between controls and AL-treated animals. Moreover, the histological findings showed that AL treatment can prevent mucosal edema, submucosal erosions, ulceration, inflammatory cell infiltration and colon damage. In addition, immunohistochemistry analysis showed that the levels of the inflammatory cytokines, IL-6 and TNF-? were also decreased in AL-treated groups. CONCLUSION: We suggest that AL can prevent intestinal damage and decrease inflammatory cytokines in mice with DSS-induced colitis. Thus, AL could prove to be a useful food for UC. PMID:20806438

Huang, Tzou-Chi; Tsai, Shinn-Shyong; Liu, Li-Fang; Liu, Yu Lin; Liu, Hung-Jen; Chuang, Kuo Pin

2010-01-01

112

Comparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis and restricted fragment length polymorphism among fenugreek accessions.  

PubMed

Protein and DNA polymorphismswere surveyed among seven accessions of wild fenugreek (Trigonellafoenum-graecum L.) to estimate their genetic diversity and relationships. Samples were obtained from diverse ecogeographical areas in Saudi Arabia and Yemen. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis of seed storage protein showed genetic variations among fenugreek germplasms, both quantitatively and qualitatively, generating a total of 168 polypeptide bands with different molecular weights ranging from 4.5 to 300 kDa. Twenty-six of these bands were polymorphic, with a considerable polymorphism value (80.00%). Furthermore, restriction fragment length polymorphism (RFLP) analysis was also employed, which was based on the ability of four restriction enzymes (EagI, EcoRI, FspI, and HindIII) to cleave genomic DNA of the plant materials at specific target nucleotide sequences into different numbers of DNA fragments. RFLP analysis revealed 166 fragments with known sequences and variable lengths ranging from 80 to 4000 bp with a highly degree of polymorphism (88.71%). Data derived from SDS-PAGE or RFLP analyses were used to produce dendrograms, which clustered the studied fenugreek accessions into different groups based on the unweighted pair group method with arithmetic mean (UPGMA). The resulting relationships indicated that these two marker techniques were nearly equivalent, but not identical, with respect to phylogenetic information. In conclusion, SDS-PAGE analysis of seed proteins should be augmented with RFLP analysis of DNA for reliable estimates of genetic diversity among fenugreek germplasms. PMID:24338424

Haliem, E A; Al-Huqail, A A

2013-01-01

113

Effect of sodium dodecyl sulfate on protein separation by hollow fiber flow field-flow fractionation.  

PubMed

Effects of protein denaturation and formation of protein-sodium dodecyl sulfate (SDS) complexes on protein separation and identification were investigated using hollow fiber flow field-flow fractionation (HF5) and nanoflow liquid chromatography-electrospray ionization-tandem mass spectrometry (nLC-ESI-MS-MS). Denaturation and formation of protein-SDS complexes prior to HF5 separation resulted an increase in the retention of few protein standards due to unfolding of the protein structures and complexation, yielding ~30% increase in hydrodynamic diameter. In addition, low molecular weight proteins which could be lost from the HF membrane due to the pore size limitation showed an increase of peak recovery about 2-6 folds for cytochrome C and carbonic anhydrase. In the case of proteins composed of a number of subunits, denaturation resulted in a decrease in retention due to dissociation of protein subunits. A serum proteome sample, denatured with dithiothreitol and SDS, was fractionated by HF5, and the eluting protein fractions after tryptic digestion were analyzed for protein identification using nLC-ESI-MS-MS. The resulting pools of identified proteins were found to depend on whether the serum sample was treated with or without denaturation prior to the HF5 run due to differences in the aqueous solubility of the proteins. The enhancement of protein solubility by SDS also increased the number of identified membrane proteins (54 vs. 31). PMID:20963232

Kim, Ki Hun; Lee, Ju Yong; Moon, Myeong Hee

2011-01-21

114

Microfluidic integration of Western blotting is enabled by electrotransfer-assisted sodium dodecyl sulfate dilution.  

PubMed

We integrate sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) with subsequent antibody probing in a single, monolithic microdevice to realize microfluidic Western blotting. A hurdle to successful on-chip Western blotting lies in restoring antibody recognition of previously sized (denatured, reduced) proteins. To surmount this hurdle, we locally dilute free SDS from SDS-protein complexes using differential electromigration of the species during electrotransfer between SDS-PAGE and blotting regions of a microchamber. Local dilution of SDS minimizes re-association of SDS with proteins offering means to restore antibody binding affinity to proteins after SDS-PAGE. To achieve automated, programmable operation in a single instrument, we utilize a 1 × 2 mm(2) glass microchamber photopatterned with spatially distinct, contiguous polyacrylamide regions for SDS-PAGE, electrotransfer, and antibody blotting. Optimization of both the SDS-PAGE and electrotransfer conditions yields transfer distances of <1 mm (40 s). The Western blot is completed in 180 s, with fully automated assay operation using programmable voltage control. After SDS-PAGE and electrotransfer, we observe ~80% capture of protein band mass on the blotting region for a model protein, C-reactive protein. This novel microfluidic Western blot approach introduces fine transport control for in-transit protein handling to form the basis for an automated, rapid alternative to conventional slab-gel Western blotting. PMID:23042290

Hou, Chenlu; Herr, Amy E

2013-01-01

115

Simple Sodium Dodecyl Sulfate-Assisted Sample Preparation Method for LC-MS-based Proteomic Applications  

SciTech Connect

Sodium dodecyl sulfate (SDS) is one of the most popular laboratory reagents used for highly efficient biological sample extraction; however, SDS presents a significant challenge to LC-MS-based proteomic analyses due to its severe interference with reversed-phase LC separations and electrospray ionization interfaces. This study reports a simple SDS-assisted proteomic sample preparation method facilitated by a novel peptide-level SDS removal protocol. After SDS-assisted protein extraction and digestion, SDS was effectively (>99.9%) removed from peptides through ion substitution-mediated DS- precipitation with potassium chloride (KCl) followed by {approx}10 min centrifugation. Excellent peptide recovery (>95%) was observed for less than 20 {mu}g of peptides. Further experiments demonstrated the compatibility of this protocol with LC-MS/MS analyses. The resulting proteome coverage from this SDS-assisted protocol was comparable to or better than those obtained from other standard proteomic preparation methods in both mammalian tissues and bacterial samples. These results suggest that this SDS-assisted protocol is a practical, simple, and broadly applicable proteomic sample processing method, which can be particularly useful when dealing with samples difficult to solubilize by other methods.

Zhou, Jianying; Dann, Geoffrey P.; Shi, Tujin; Wang, Lu; Gao, Xiaoli; Su, Dian; Nicora, Carrie D.; Shukla, Anil K.; Moore, Ronald J.; Liu, Tao; Camp, David G.; Smith, Richard D.; Qian, Weijun

2012-03-10

116

Immunological alteration and changes of gut microbiota after dextran sulfate sodium (DSS) administration in mice.  

PubMed

Ulcerative colitis (UC) is characterized by chronic inflammation of the colonic mucosa. Administration of dextran sulfate sodium (DSS) to animals is a frequently used model to mimic human colitis. Deregulation of the immune response to the enteric microflora or pathogens as well as increased intestinal permeability have been proposed as disease-driving mechanisms. To enlarge the understanding of the pathogenesis, we have studied the effect of DSS on the immune system and gut microbiota in mice. Intestinal inflammation was verified through histological evaluation and myeloperoxidase activity. Immunological changes were assessed by flow cytometry in spleen, Peyer's patches and mesenteric lymph nodes and through multiplex cytokine profiling. In addition, quantification of the total amount of bacteria on colonic mucosa as well as the total amount of lactobacilli, Akkermansia, Desulfovibrio and Enterobacteriaceae was performed by the use of quantitative PCR. Diversity and community structure were analysed by terminal restriction fragment length polymorphism (T-RFLP) patterns, and principal component analysis was utilized on immunological and T-RFLP patterns. DSS-induced colitis show clinical and histological similarities to UC. The composition of the colonic microflora was profoundly changed and correlated with several alterations of the immune system. The results demonstrate a relationship between multiple immunological changes and alterations of the gut microbiota after DSS administration. These data highlight and improve the definition of the immunological basis of the disease and suggest a role for dysregulation of the gut microbiota in the pathogenesis of colitis. PMID:24414342

Håkansson, Å; Tormo-Badia, N; Baridi, A; Xu, J; Molin, G; Hagslätt, M-L; Karlsson, C; Jeppsson, B; Cilio, C M; Ahrné, S

2015-02-01

117

Self-assembly of ionic detergents: a simulation study of sodium dodecyl sulfate micellization  

NASA Astrophysics Data System (ADS)

Detergents, amphiphilic molecules used to separate and dissolve molecular aggregates and also as cleaning agents, consist of a polar head group and one or more hydrophobic tails. Above a critical concentration, they self-aggregate in an aqueous solution to form micelles. While industrially extremely important, surprisingly little is known about molecular details of the self-assembly of detergents. Here we extend our previous work of modeling and model construction of charged soft-matter systems [1] by a description of an anionic detergent, sodium dodecyl sulfate (SDS) [2]. We present the results of large-scale Molecular Dynamics simulations of the formation dynamics and structure of SDS micelles. We demonstrate that temperature affects micelle morphologies through the packing and discuss the effect of SDS concentration on the micellization. [1] M. Patra et al., Biophys. J. 84, 3636 (2003); A. A. Gurtovenko et al., J. Phys. Chem. B 109, 21126 (2005); A. A. Gurtovenko et al., Biophys. J. 86, 3461 (2004). [2] The SDS parameters are available at www.softsimu.org.

Sammalkorpi, Maria; Karttunen, Mikko; Haataja, Mikko

2007-03-01

118

Nociceptin/orphanin FQ inhibition with SB612111 ameliorates dextran sodium sulfate-induced colitis.  

PubMed

Inflammatory bowel diseases, primarily Crohn's disease and ulcerative colitis, are chronic inflammatory disorders of the gastrointestinal tract with unknown etiology. The majority of current therapeutic agents focus on controlling proinflammatory molecules. The neuropeptide nociceptin/orphanin FQ (N/OFQ) has been described as a potential immunomodulator for inflammatory bowel diseases. In this study, we asked whether the small molecule N/OFQ antagonist (-)-cis-1-methyl-7-[[4-(2,6-dichlorophenyl)piperidin-1-yl]methyl]-6,7,8,9-tetrahydro-5H-benzocyclohepten-5-ol (SB612111) would inhibit the development of dextran sodium sulfate-induced colitis in C57BL/6 mice. Inhibition of the N/OFQ receptor (NOP) by SB612111 significantly ameliorated the clinical disease course in these animals, as indicated by reduced fecal bleeding, improved recovery from diarrhea and weight loss, and a reduction in histopathological alterations. In addition, the inflammatory response in the colon was diminished, as demonstrated by reduced cytokine protein and messenger RNA expression for CXCL1/keratinocyte-derived chemokine, interferon-?, interleukin-1?, interleukin-6, and tumor necrosis factor-?, some of which are known targets for the treatment of this devastating disease. Our results strongly support a role for the receptor-ligand pair NOP-N/OFQ in the pathogenesis of colitis. We conclude that inhibition of NOP receptors with small molecule inhibitors may constitute a novel, urgently needed approach for the treatment of inflammatory bowel diseases. PMID:22449384

Alt, Carsten; Lam, Jennifer S; Harrison, M Travis; Kershaw, Kathleen M; Samuelsson, Steven; Toll, Lawrence; D'Andrea, Annalisa

2012-05-15

119

Panax notoginseng attenuates experimental colitis in the azoxymethane/dextran sulfate sodium mouse model.  

PubMed

Patients suffering from inflammatory bowel disease are at a high risk of developing colorectal cancer. To assess the anticancer potential of botanicals, in this study, we evaluated the effects of Panax notoginseng on azoxymethane/dextran sulfate sodium (DSS)-induced colitis. One week after A/J mice received azoxymethane, the animals received DSS for 8?days or were supplemented with P.?notoginseng extract, at 30 or 90?mg/kg. DSS-induced colitis was scored with the disease activity index. The severity of the inflammatory lesions was evaluated by a colon tissue histological assessment. The expression of inducible nitric oxide synthase and cyclooxygenase-2 (COX-2) were also explored. We observed that the effects of P.?notoginseng on the reduction of colon inflammation, expressed in disease activity index score, were in a dose-related manner (p?

Wen, Xiao-Dong; Wang, Chong-Zhi; Yu, Chunhao; Zhao, Lei; Zhang, Zhiyu; Matin, Adiba; Wang, Yunwei; Li, Ping; Xiao, Shu-Yuan; Du, Wei; He, Tong-Chuan; Yuan, Chun-Su

2014-06-01

120

Mass and surface fractal in supercritical dried silica aerogels prepared with additions of sodium dodecyl sulfate.  

PubMed

Silica wet gels were prepared from hydrolysis of tetraethoxysilane (TEOS) with additions of sodium dodecyl sulfate (SDS). The surfactant was removed after gelation. Wet gels exhibited mass-fractal structure with mass-fractal dimension D (typically around 2.25) in a length scale extending from a characteristic size ? (typically about 10 nm) of the mass-fractal domains to a characteristic size a0 (typically between 0.3 and 0.4 nm) of the primary particles building up the fractal domains. ? increased while D and a0 diminished slightly as the SDS quantity increased. Aerogels with typical specific surface of 1000 m(2)/g and density of 0.20 g/cm(3) were obtained by supercritical drying of the wet gels after washing with ethanol and n-hexane. The pore volume and the mean pore size increased with the increase of the SDS quantity. The aerogels presented most of the mass-fractal characteristics of the original wet gels at large length scales and exhibited at a higher resolution level at about 0.7 nm a crossover to a mass-surface fractal structure, with apparent mass-fractal dimension Dm ? 2.4 and surface-fractal dimension Ds ? 2.6, as inferred from small-angle X-ray scattering (SAXS) and nitrogen adsorption data. PMID:25513729

Perissinotto, Amanda P; Awano, Carlos M; Donatti, Dario A; de Vicente, Fabio S; Vollet, Dimas R

2015-01-13

121

Platelets to rings: Influence of sodium dodecyl sulfate on Zn-Al layered double hydroxide morphology  

SciTech Connect

In the current study, influence of sodium dodecyl sulfate (SDS) on the crystallization of Zn-Al layered double hydroxide (LDH) was investigated. Depending on the SDS concentration coral-like and for the first time ring-like morphologies were obtained in a urea-hydrolysis method. It was revealed that the surfactant level in the starting solution plays an important role in the morphology. Concentration of surfactant equal to or above the anion exchange capacity of the LDH is influential in creating different morphologies. Another important parameter was the critical micelle concentration (CMC) of the surfactant. Surfactant concentrations well above CMC value resulted in ring-like structures. The crystallization mechanism was discussed. - Graphical abstract: Dependence of ZnAl LDH Morphology on SDS concentration. Highlights: Black-Right-Pointing-Pointer In-situ intercalation of SDS in ZnAl LDH was achieved via urea hydrolysis method. Black-Right-Pointing-Pointer Morphology of ZnAl LDH intercalated with SDS depended on the SDS concentration. Black-Right-Pointing-Pointer Ring like morphology for SDS intercalated ZnAl LDH was obtained for the first time. Black-Right-Pointing-Pointer Growth mechanism was discussed. Black-Right-Pointing-Pointer Template assisted growth of ZnAl LDH was proposed.

Yilmaz, Ceren [Graduate School of Science and Engineering, Koc University, Rumelifeneri Yolu, Sariyer 34450, Istanbul (Turkey); Unal, Ugur [Graduate School of Science and Engineering, Koc University, Rumelifeneri Yolu, Sariyer 34450, Istanbul (Turkey); Koc University, Chemistry Department, Rumelifeneri yolu, Sariyer 34450, Istanbul (Turkey); Koc University, Surface Science and Technology Center, KUYTAM, Rumelifeneri yolu, Sariyer 34450, Istanbul (Turkey); Yagci Acar, Havva, E-mail: fyagci@ku.edu.tr [Graduate School of Science and Engineering, Koc University, Rumelifeneri Yolu, Sariyer 34450, Istanbul (Turkey); Koc University, Chemistry Department, Rumelifeneri yolu, Sariyer 34450, Istanbul (Turkey); Koc University, Surface Science and Technology Center, KUYTAM, Rumelifeneri yolu, Sariyer 34450, Istanbul (Turkey)

2012-03-15

122

Structural transition of the sodium dodecyl sulfate (SDS) surfactant induced by changes in surfactant concentrations.  

PubMed

Molecular dynamics simulations were used to investigate aggregation of surfactants at the solid-liquid interface at different surfactant concentrations. For these studies simulations of the sodium dodecyl sulfate (SDS) surfactant with a graphite surface were carried out. At low concentrations the SDS molecules aggregated in slices of cylinders attached to the solid surface, whereas at slightly higher concentrations the structures showed irregular shapes. When the concentration was again increased to a higher value, the molecules aggregated in a more complex structure, an irregular aggregate on the top of a semicylinder adsorbed on the graphite surface. From the present results more insights about the internal structure of the aggregates were observed than in actual experiments, e.g., it was found that the SDS tails arrayed in well-defined layers close to the graphite surface. More over, from the internal structure it was possible to show a structural transition driven by an increment in the surfactant concentration which, to the best of our knowledge, has not been studied from a molecular point of view. Therefore the transition was studied in terms of the height of the structures. Along with these studies adsorption of the aggregates, by calculating contact angles, and adsorption isotherms were also analyzed. Finally, investigations of the surface coverage with the concentration showed that this quantity did not change considerably with the concentration. PMID:21923149

Domínguez, Hector

2011-11-01

123

Electrochemistry of cytochrome P450 BM3 in sodium dodecyl sulfate films.  

PubMed

Direct electrochemistry of the cytochrome P450 BM3 heme domain (BM3) was achieved by confining the protein within sodium dodecyl sulfate (SDS) films on the surface of basal-plane graphite (BPG) electrodes. Cyclic voltammetry revealed the heme FeIII/II redox couple at -330 mV (vs Ag/AgCl, pH 7.4). Up to 10 V/s, the peak current was linear with the scan rate, allowing us to treat the system as surface-confined within this regime. The standard heterogeneous rate constant determined at 10 V/s was estimated to be 10 s-1. Voltammograms obtained for the BM3-SDS-BPG system in the presence of dioxygen exhibited catalytic waves at the onset of FeIII reduction. The altered heme reduction potential of the BM3-SDS-graphite system indicates that SDS is likely bound in the enzyme active-site region. Compared to other P450-surfactant systems, we find redox potentials and electron-transfer rates that differ by approximately 100 mV and >10-fold, respectively, indicating that the nature of the surfactant environment has a significant effect on the observed heme redox properties. PMID:17129070

Udit, Andrew K; Hill, Michael G; Gray, Harry B

2006-12-01

124

Dispersion stability of functionalized graphene in aqueous sodium dodecyl sulfate solutions.  

PubMed

The colloidal stability of functionalized graphene sheets (FGSs) in aqueous sodium dodecyl sulfate (SDS) solutions of different concentrations was studied by optical microscopy and ultraviolet-visible light absorption after first dispersing the FGSs ultrasonically. In up to ?10 ?M SDS solutions, FGSs reaggregated within a few minutes, forming ramified structures in the absence of SDS and increasingly compact structures as the amount of SDS increased. Above ?10 ?M, the rate of reaggregation decreased with increasing SDS concentration; above ?40 ?M, the suspensions were colloidally stable for over a year. The concentration of ?40 ?M SDS lies 2 orders of magnitude below the critical surface aggregation concentration of ?1.8 mM SDS on FGSs but above the concentration (?18 ?M) at which SDS begins to form a monolayer on FGSs. Neither surface micelle nor dense monolayer coverage is therefore required to obtain stable aqueous FGS dispersions. We support our experimental results by calculating the van der Waals and electrostatic interaction energies between FGSs as a function of SDS concentration and show that the experimentally observed transition from an unstable to a stable dispersion correlates with a transition from negative to positive interaction energies between FGSs in the aggregated state. Furthermore, our calculations support experimental evidence that aggregates tend to develop a compact structure over time. PMID:24188504

Hsieh, Andrew G; Korkut, Sibel; Punckt, Christian; Aksay, Ilhan A

2013-12-01

125

American ginseng attenuates azoxymethane/dextran sodium sulfate-induced colon carcinogenesis in mice  

PubMed Central

Background Colorectal cancer is a leading cause of cancer-related death, and inflammatory bowel disease is a risk factor for this malignancy. We previously reported colon cancer chemoprevention potential using American ginseng (AG) in a xenograft mice model. However, the nude mouse model is not a gut-specific colon carcinogenesis animal model. Methods In this study, an experimental colitis and colitis-associated colorectal carcinogenesis mouse model, chemically induced by azoxymethane/dextran sodium sulfate (DSS) was established and the effects of oral AG were evaluated. The contents of representative ginseng saponins in the extract were determined. Results AG significantly reduced experimental colitis measured by the disease activity index scores. This suppression of the experimental colitis was not only evident during DSS treatment, but also very obvious after the cessation of DSS, suggesting that the ginseng significantly promoted recovery from the colitis. Consistent with the anti-inflammation data, we showed that ginseng very significantly attenuated azoxymethane/DSS-induced colon carcinogenesis by reducing the colon tumor number and tumor load. The ginseng also effectively suppressed DSS-induced proinflammatory cytokines activation using an enzyme-linked immunosorbent assay array, in which 12 proinflammatory cytokine levels were assessed, and this effect was supported subsequently by real-time polymerase chain reaction data. Conclusion AG, as a candidate of botanical-based colon cancer chemoprevention, should be further investigated for its potential clinical utility.

Yu, Chunhao; Wen, Xiao-Dong; Zhang, Zhiyu; Zhang, Chun-Feng; Wu, Xiao-Hui; Martin, Adiba; Du, Wei; He, Tong-Chuan; Wang, Chong-Zhi; Yuan, Chun-Su

2014-01-01

126

Management of stomal varices with transvenous obliteration utilizing sodium tetradecyl sulfate foam sclerosis.  

PubMed

The management of parastomal varices is not established. Transjugular intrahepatic portosystemic shunt (TIPS) creation is the most commonly described treatment; however, the rebleed rate after TIPS is 21-37%. The purpose of the study is to determine the effectiveness of transvenous obliteration using sodium tetradecyl sulfate (STS) and to describe a new simplified technique in obliterating these varices. Four patients are presented who underwent transvenous obliteration using STS. One was obliterated using balloon occlusion from the systemic veins, the second was obliterated without balloon from a transhepatic antegrade approach, and the last two patients were obliterated using the direct antegrade technique. This simplified technique requires only a micropuncture kit (not requiring balloons or coils) and ultrasound transducer compression of the systemic draining veins, relying on high portal pressure to keep the sclerosant confined to the varices. The sclerosant is essentially trapped between the portal pressure and the ultrasound-transducer compression (10-15 min). Technical success was achieved in all four patients without procedural or postprocedural complications and no rebleeding for a mean follow-up of 17 (range 2-33) months. Transvenous obliteration of parastomal varices utilizing STS as a sclerosant is safe and effective. The newly described technique is simple, feasible, and requires minimal equipment (no balloons or coils or catheters). PMID:24798128

Saad, Wael E A; Schwaner, Sandra; Lippert, Allison; Sabri, Saher S; Al-Osaimi, Abdullah; Matsumoto, Alan H; Angle, John F; Caldwell, Stephen

2014-12-01

127

Effects of Sodium Dodecyl Sulfate on Structures of Poly(N-isopropylacrylamide) at the Particle Surface.  

PubMed

The effect of sodium dodecyl sulfate (SDS) on the poly(N-isopropylacrylamide) (PNIPAM) tethered to nanoparticles was experimentally investigated using dynamic light scattering below the lower critical solution temperature. A mean-field analytical model was used to calculate the parameters of interfacial PNIPAM-SDS complexes. Particularly, the magnitude of SDS adsorption energy obtained decreases with decreasing excluded volume parameter, implying that the partially collapsed PNIPAM brush virtually favors the adsorption of SDS onto the PNIPAM chains. A self-consistent field theory (SCFT) model was used to get a detailed quantitative description of monomer density distribution. By lowering the solvent quality, a number of phenomena related to the noncontinuity of monomer density are revealed. These phenomena are either referred to as the vertical phase separation or as its precursor, which can be delayed and eventually eliminated as the SDS coverage is increased. The distribution of free chain ends was calculated using the SCFT model. Increasing the SDS coverage gives rise to a broader and more asymmetric distribution of free chain ends, accompanied by a considerable expansion of the dead zone (below which the free chain ends do not exist), but lowering the solvent quality has opposite influences. The relative thickness of the dead zone can be scaled to a master curve, regardless of SDS coverage. PMID:25493920

Zhu, Peng Wei

2015-01-01

128

Proteus mirabilis sp. intestinal microflora grow in a dextran sulfate sodium-rich environment.  

PubMed

The pathogenic mechanisms responsible for inflammatory bowel disease, especially ulcerative colitis (UC), are poorly understood. As an animal model, the oral administration of dextran sulfate sodium (DSS) induces colitis, which exhibits several clinical and histological features similar to UC. However, the pathogenic factors responsible for DSS-induced colitis and above all, the intestinal microflora in this colitis remain unclear. Therefore, we investigated the relationships between DSS and the intestinal microflora in this study. First, the depolymerization of DSS in mouse feces was analyzed using a pyridylamino-labeling (PA-DSS) and HPLC system. Next, a bacteriological study of the fecal contents using DSS-rich media and subsequently a classification using 16S rRNA were performed. Surprisingly, DSS was depolymerized in mouse feces under aerobic conditions, not under anaerobic conditions. Several kinds of microflora were suggested to be involved in this depolymerization. In particular, Proteus mirabilis can grow in DSS-rich media and has an ability to desulfonate and depolymerize DSS. Then, we produced chemically-modified Mr 2500 DSS from native Mr 5000 DSS. This depolymerized Mr 2500 DSS was administered orally to mice and the colitis was evaluated histologically. The cytotoxicity of Mr 2500 DSS on Caco-2 cells was also investigated. Mr 2500 DSS induced weaker colitis in mice and weak cytotoxicity on Caco-2 cells as compared to Mr 5000 DSS. These findings give insight into the mechanisms responsible for DSS-induced colitis, especially with respect to the molecular mass of DSS. PMID:20043128

Araki, Yoshio; Mukaisho, Kenichi; Sugihara, Hiroyuki; Fujiyama, Yoshihide; Hattori, Takanori

2010-02-01

129

Dietary taurine attenuates dextran sulfate sodium (DSS)-induced experimental colitis in mice.  

PubMed

Effects of dietary taurine on the experimental colitis induced by dextran sulfate sodium (DSS) were studied. C57BL/6 mice administrated taurine or placebo for 5 days were given 3% DSS to induce acute. The colitis was as-sessed using indices such as diarrhea/bleeding scores, colon length change, histological score and tissue myeloperoxidase (MPO) activity. Further, tissue mRNA levels of interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha and macrophage inflammatory protein (MIP)-2, were determined by real-time PCR. Taurine supplementation significantly attenuated the severity of diarrhea, colon shortening, histological score, MPO activity elevation and abnormal MIP-2 gene expression, indicating that taurine prevents DSS-induced colitis. Taurine also inhibited the TNF-alpha-induced secretion of IL-8 (a human homologue of MIP-2) from human intestinal epithelial Caco-2 cells. Inhibition of chemokine secretion from intestinal cells may be involved in the mechanisms underlying the cytoprotective function of taurine in the intestinal epithelium. PMID:19239157

Shimizu, Makoto; Zhao, Zhaohui; Ishimoto, Yoko; Satsu, Hideo

2009-01-01

130

Dietary Uptake of Wedelia chinensis Extract Attenuates Dextran Sulfate Sodium-Induced Colitis in Mice  

PubMed Central

Scope Traditional medicinal herbs are increasingly used as alternative therapies in patients with inflammatory diseases. Here we evaluated the effect of Wedelia chinensis, a medicinal herb commonly used in Asia, on the prevention of dextran sulfate sodium (DSS)-induced acute colitis in mice. General safety and the effect of different extraction methods on the bioactivity of W. chinensis were also explored. Methods and Results C57BL/6 mice were administrated hot water extract of fresh W. chinensis (WCHF) orally for one week followed by drinking water containing 2% DSS for nine days. WCHF significantly attenuated the symptoms of colitis including diarrhea, rectal bleeding and loss of body weight; it also reduced the shortening of colon length and histopathological damage caused by colonic inflammation. Among four W. chinensis extracts prepared using different extraction techniques, WCHF showed the highest anti-colitis efficacy. Analyses of specific T-cell regulatory cytokines (TNF-?, IL-4, IFN-?, IL-17, TGF-?, IL-12) revealed that WCHF treatment can suppress the Th1 and Th17, but not Th2, responses in colon tissues and dendritic cells of DSS-induced colitis mice. A 28-day subacute toxicity study showed that daily oral administration of WCHF (100, 500, 1000 mg/kg body weight) was not toxic to mice. Conclusion Together, our findings suggest that specific extracts of W. chinensis have nutritional potential for future development into nutraceuticals or dietary supplements for treatment of inflammatory bowel disease. PMID:23734189

Chen, Yung-Hsiang; Huang, Wen-Ching; Huang, Li-Ting; Lin, Wen-Ching; Arulselvan, Palanisamy; Liao, Jiunn-Wang; Lin, Shu-Hui; Hsiao, Pei-Wen; Kuo, Sheng-Chu; Yang, Ning-Sun

2013-01-01

131

Quasi-elastic light scattering study of intermicellar interactions in aqueous sodium dodecyl sulfate solutions  

SciTech Connect

Quasi-elastic light scattering measurement have been performed on aqueous sodium dodecyl sulfate solutions in the 0.1 to 0.6 mole NaCl concentration range at 25 and 40 C. The aggregation number M, the hydrodynamic radius Rh, and the amphiphile concentration dependence of static and transport coefficients of micellar solutions are obtained from the experimental data. The micellar parameters M and Rh increase with salt concentration and slightly decrease with temperature. The concentration dependence of the apparent molecular weight and of the mass diffusion coefficient is interpreted on the basis of Derjaguin-Landau-Verwey-Overbeek theory of colloid stability. The fit to the experimental data, performed with the assumption that the Hamaker constant for micellar attraction A and the micellar electric charge Q do not depend on the salt concentration, is satisfactory and gives A = 4.5 x 10/sup -20/ J and Q = 37 electronic charges. The electric potential at the shear surface of the micelle goes from 70 MV at 0.1 mole NaCl to approximately 30 MV at 0.5 to 0.6 mole NaCl. 45 references.

Corti, M.; Deglorgio, V.

1981-03-19

132

Modification of an acetone-sodium dodecyl sulfate disruption method for cellular protein extraction from neurotoxigenic Clostridium botulinum.  

PubMed

An acetone-sodium dodecyl sulfate disruption method was used for the extraction of cellular proteins from neurotoxigenic Clostridium botulinum. The amount of protein extracted per gram of dry weight and the protein profile as revealed by polyacrylamide gel electrophoresis was comparable to the extracts prepared by established methods, namely, sonication or agitation with beads. This method allows safer handling of C. botulinum by avoiding mechanical disruption, the generation of aerosols, and contamination of the apparatus. PMID:22044259

Bhaduri, Saumya

2012-02-01

133

Corrosion resistance of sodium sulfate coated cobalt-chromium-aluminum alloys at 900 C, 1000 C, and 1100 C  

NASA Technical Reports Server (NTRS)

The corrosion of sodium sulfate coated cobalt alloys was measured and the results compared to the cyclic oxidation of alloys with the same composition, and to the hot corrosion of compositionally equivalent nickel-base alloys. Cobalt alloys with sufficient aluminum content to form aluminum containing scales corrode less than their nickel-base counterparts. The cobalt alloys with lower aluminum levels form CoO scales and corrode more than their nickel-base counterparts which form NiO scales.

Santoro, G. J.

1979-01-01

134

A paper-based electroelution system for protein recovery from stained sodium dodecyl sulfate-polyacrylamide gels.  

PubMed

Electroelution is a widely used methodology for protein purification. In this study, a practical and low-cost system for protein electroelution from stained polyacrylamide gels was developed. For this, a horizontal protein electroelution cuve was constructed with glass plates, 1.5-ml capacity microcentrifuge tubes, and dialysis membrane. Analyses of the system efficiency showed high protein recovery from nonfixed and fixed sodium dodecyl sulfate (SDS)-polyacrylamide gels. PMID:18396142

Branco, Alan T; Ferreira, Beatriz dos S; de Souza Filho, Gonçalo A

2008-10-15

135

Solubilization Site of Organic Perfume Molecules in Sodium Dodecyl Sulfate Micelles: New Insights from Proton NMR Studies  

Microsoft Academic Search

The site of incorporation of solubilizates in sodium dodecyl sulfate (SDS) micellar systems has been investigated by proton NMR spectroscopy. The solubilizate molecules chosen for the present study are phenol, 4-methylphenol, 4-allyl-2-methoxyphenol, anisole, 4-methylanisole, 4-propenylanisole, 1,8-cineole, and limonene. These molecules possess a wide variety of functional groups with different degrees of hydrophilic\\/hydrophobic character and are thereby solubilized at different micellar

Varsha Suratkar; Samiran Mahapatra

2000-01-01

136

Sulfite Oxidation in Chlorobaculum Tepidum  

PubMed Central

The green sulfur bacterium Chlorobaculum tepidum is proposed to oxidize sulfide and elemental sulfur via sulfite as an obligate intermediate. The sulfite pool is predicted to be contained in the cytoplasm and be oxidized by the concerted action of ApsBA, which directly oxidizes sulfite, and QmoABC, which transfers electrons from ApsBA to the quinone pool. Like other green sulfur bacteria, C. tepidum was unable to use exogenously provided sulfite as the sole electron donor. However, exogenous sulfite significantly stimulated the growth yield of sulfide limited batch cultures. The growth of C. tepidum mutant strains, CT0867/qmoB::TnOGm and CT0868/qmoC::TnOGm, was not increased by sulfite. Furthermore, these strains accumulated sulfite and displayed a growth yield decrease when grown on sulfide as the sole electron donor. These results support an obligate, cytoplasmic sulfite intermediate as part of the canonical sulfur oxidation pathway in C. tepidum that requires the Qmo complex for oxidation. PMID:21747809

Rodriguez, Jesse; Hiras, Jennifer; Hanson, Thomas E.

2011-01-01

137

Transport Pathways and Enhancement Mechanisms within Localized and Non-Localized Transport Regions in Skin Treated with Low-Frequency Sonophoresis and Sodium Lauryl Sulfate  

E-print Network

Recent advances in transdermal drug delivery utilizing low-frequency sonophoresis (LFS) and sodium lauryl sulfate (SLS) have revealed that skin permeability enhancement is not homogenous across the skin surface. Instead, ...

Polat, Baris E.

138

A novel sulfite alternative scavenger and benefits for the use of traced oxygen scavengers  

SciTech Connect

Dissolved oxygen in boiler systems is known to cause corrosion. Mechanical deaeration removes the majority of the dissolved oxygen while oxygen scavengers remove the remaining trace level. Sodium sulfate is a commonly used scavenger, but has several use limitations, such as high solids contribution to boiler water and decomposition products that are corrosive gases which can cause downstream equipment problems. A novel sulfite replacement oxygen scavenger has been developed which addresses the limitations of sulfite. Identification and demonstrated performance of the new scavenger is presented using both research and field data. In addition to oxygen scavenger performance, the success of a boiler water treatment program is dependent upon the correct dosage added to the feedwater. Plant managers and operators often struggle with indirect or inaccurate methods to determine what is occurring within their system. An oxygen scavenger product containing a proprietary fluorescent tracer has been developed. This technology for boilers provides a breakthrough in measurement capability for monitoring the dynamics of a boiler system. These two oxygen scavenger developments represent the result of maintaining desirable performance characteristics and significantly improving current technology. Laboratory and field data supporting these results are presented.

Batton, C.B.; Riede, R.F. [Nalco Chemical Co., Naperville, IL (United States)

1994-12-31

139

Investigation of the chemical pathway of gaseous nitrogen dioxide formation during flue gas desulfurization with dry sodium bicarbonate injection  

NASA Astrophysics Data System (ADS)

The chemical reaction pathway for the viable flue gas desulfurization process, dry sodium bicarbonate injection, was investigated to mitigate undesirable plume discoloration. Based on a foundation of past findings, a simplified three-step reaction pathway was hypothesized for the formation of the plume-discoloring constituent, NO2. As the first step, it was hypothesized that sodium sulfite formed by sodium bicarbonate reaction with flue gas SO 2. As the second step, it was hypothesized that sodium nitrate formed by sodium sulfite reaction with flue gas NO. And as the third step, it was hypothesized that NO2 and sodium sulfate formed by sodium nitrate reaction with SO2. The second and third hypothesized steps were experimentally investigated using an isothermal fixed bed reactor. As reported in the past, technical grade sodium sulfite was found to be un-reactive with NO and O2. Freshly prepared sodium sulfite, maintained unexposed to moist air, was shown to react with NO and O2 resulting in a mixture of sodium nitrite and sodium nitrate together with a significant temperature rise. This reaction was found to proceed only when oxygen was present in the flue gas. As reported in the past, technical grade sodium nitrate was shown to be un-reactive with SO2. But freshly formed sodium nitrate kept unexposed to humidity was found to be reactive with SO2 and O 2 resulting in the formation of NO2 and sodium sulfate polymorphic Form I. The NO2 formation by this reaction was shown to be temperature dependent with maximum formation at 175°C. Plume mitigation methods were studied based on the validated three-step reaction pathway. Mitigation of NO2 was exhibited by limiting oxygen concentration in the flue gas to a level below 5%. It was also shown that significant NO2 mitigation was achieved by operating below 110°C or above 250°C. An innovative NO2 mitigation method was patented as a result of the findings of this study. The patented process incorporated a process step of sodium sulfite injection to remove flue gas NO prior to sodium bicarbonate injection.

Stein, Antoinette Weil

140

Dextran sulfate sodium leads to chronic colitis and pathological angiogenesis in Endoglin heterozygous mice  

PubMed Central

Background Pathological angiogenesis is an intrinsic component of chronic intestinal inflammation, which results in remodeling and expansion of the gut microvascular bed. Endoglin is essential for endothelial cell function and physiological angiogenesis. In this study, we investigated its potential role in the regulation of inflammation by testing the response of Endoglin heterozygous (Eng+/-) mice to experimental colitis. Methods C57BL/6 Eng+/- and littermate control mice drank water supplemented with 3% dextran sulfate sodium (DSS) for 5 days and were monitored for up to 26 days for clinical signs of colitis. Inflammation, crypt damage and angiogenic index were scored on histological sections of distal colon. Levels of the vascular endothelial growth factor (VEGF) and angiopoietins were measured by real time polymerase chain reaction, ELISA and/or Western blots. Vascular permeability was assessed using Evans Blue. Results Eng+/- and control mice developed acute colitis, which peaked at day 9. While control mice recovered by days 19-26, Eng+/- mice progressed to chronic colitis and showed numerous vascular protrusions penetrating into the serosa of the inflamed distal colon. Prior to DSS induction, VEGF levels and vascular permeability were higher in the distal colon of Eng+/- mice, while angiopoietin 1 and 2 levels were unchanged. In the chronic phase of colitis, VEGF levels were increased in both groups of mice and remained significantly higher in the Eng+/- mice. Conclusions Higher VEGF levels and increased vascular permeability in the distal colon may predispose Eng+/- mice to progress to chronic and persistent bowel inflammation, associated with pathological angiogenesis. PMID:20848471

Jerkic, Mirjana; Peter, Madonna; Ardelean, Daniela; Fine, Michael; Konerding, Moritz A; Letarte, Michelle

2010-01-01

141

Pathway for Unfolding of Ubiquitin in Sodium Dodecyl Sulfate, Studied by Capillary Electrophoresis  

PubMed Central

This paper characterizes the complexes formed by a small protein, ubiquitin (UBI), and a negatively charged surfactant, sodium dodecyl sulfate (SDS), using capillary electrophoresis (CE), circular dichroism (CD), and amide hydrogendeuterium exchange (HDX; as monitored by mass spectroscopy, MS). Capillary electrophoresis of complexes of UBI and SDS, at apparent equilibrium, at concentrations of SDS ranging from sub-micellar and sub-denaturing to micellar and denaturing, revealed multiple complexes of UBI and SDS of the general composition UBI-SDSn. Examination of electrophoretic mobilities of complexes of UBI and SDS as a function of the concentration of SDS provided a new way to characterize the interaction of this protein with SDS and established key characteristics of this system: e.g., the reversibility of the formation of the complexes, their approximate chemical compositions, and the pathway of SDS binding to UBI. The work identified, in addition to SDS-saturated UBI, at least six groups of complexes of UBI with SDS, within which four groups were populated with complexes of distinct stoichiometries: UBI-SDS?11, UBI-SDS?25, UBI-SDS?33, and UBI-SDS?42. CD spectroscopy and amide HDX of the UBI-SDSn complexes suggested that many of the UBI-SDSn complexes (n > 11) have greater ?-helical content than native UBI. Capillary electrophoresis provides a level of detail about interactions of proteins and SDS that has not previously been accessible, and CE is an analytical and biophysical method for studies of interactions of proteins and surfactants that is both convenient and practical. This study sheds light on the formation of the enigmatic protein-SDS complexes formed during SDS polyacrylamide gel electrophoresis and brings a new tool to the study of proteins and detergents. PMID:19035631

Schneider, Grégory F.; Shaw, Bryan F.; Lee, Andrew; Carillho, Emanuel; Whitesides, George M.

2009-01-01

142

Transcatheter Foam Sclerotherapy of Symptomatic Female Varicocele with Sodium-Tetradecyl-Sulfate Foam  

SciTech Connect

To evaluate the efficacy of transcatheter foam sclerotherapy (TCFS) in pelvic varicocele using sodium-tetradecyl-sulfate foam (STSF), we conducted a retrospective study in 38 patients (mean age, 36.9 years; range, 22-44 years) with pelvic congestion syndrome (PCS) treated between January 2000 and June 2005 by TCFS. Pelvic pain was associated with dyspareunia in 23 (60.5%) patients, urinary urgency in 9 (23.7%) patients, and worsening of pain during menstruation and at the end of a day of work in 7 (18.4%) and 38 (100%) patients, respectively. Diagnosis was made by pelvic and transvaginal color Doppler ultrasound examination, demonstrating ovarian or pelvic varices with a diameter >5 mm presenting venous reflux. TCFS was performed in all patients, using 3% STSF. Follow-up was performed by physical examination, pelvic and transvaginal Doppler ultrasound examination and by a questionnaire-based assessment of pain at 1, 3, 6, and 12 months after the procedure. Technical success was achieved in all patients (100%). In three patients a pelvic colic-like pain occurred immediately after sclerotic agent injection, disappearing spontaneously after a few minutes. No recurrent varicoceles were observed during a 12-month follow-up. A statistically significant improvement in each category of specific symptoms was observed at 1, 3, 6, and 12 months after the procedure. We conclude that TCFS of female varicocele using a 3% STSF is safe and effective for the treatment of PCS. It is associated with a significant reduction of symptoms and can be regarded as a valid alternative to other endovascular and surgical techniques.

Gandini, Roberto; Chiocchi, Marcello, E-mail: marcello.chiocchi@fastwebnet.it; Konda, Daniel; Pampana, Enrico; Fabiano, Sebastiano; Simonetti, Giovanni [Nuclear Medicine and Radiation Therapy, University of Rome 'Tor Vergata', Department of Diagnostic and Molecular Imaging, Interventional Radiology (Italy)

2008-07-15

143

Bifidobacterium breve Attenuates Murine Dextran Sodium Sulfate-Induced Colitis and Increases Regulatory T Cell Responses  

PubMed Central

While some probiotics have shown beneficial effects on preventing or treating colitis development, others have shown no effects. In this study, we have assessed the immunomodulating effects of two probiotic strains, Lactobacillus rhamnosus (L. rhamnosus) and Bifidobacterium breve (B. breve) on T cell polarization in vitro, using human peripheral blood mononuclear cells (PBMC), and in vivo, using murine dextran sodium sulfate (DSS) colitis model. With respect to the latter, the mRNA expression of T cell subset-associated transcription factors and cytokines in the colon was measured and the T helper type (Th) 17 and regulatory T cell (Treg) subsets were determined in the Peyer's patches. Both L. rhamnosus and B. breve incubations in vitro reduced Th17 and increased Th2 cell subsets in human PBMCs. In addition, B. breve incubation was also able to reduce Th1 and increase Treg cell subsets in contrast to L. rhamnosus. In vivo intervention with B. breve, but not L. rhamnosus, significantly attenuated the severity of DSS-induced colitis. In DSS-treated C57BL/6 mice, intervention with B. breve increased the expression of mRNA encoding for Th2- and Treg-associated cytokines in the distal colon. In addition, intervention with B. breve led to increases of Treg and decreases of Th17 cell subsets in Peyer's patches of DSS-treated mice. B. breve modulates T cell polarization towards Th2 and Treg cell-associated responses in vitro and in vivo. In vivo B. breve intervention ameliorates DSS-induced colitis symptoms and this protective effect may mediated by its effects on the T-cell composition. PMID:24787575

Zheng, Bin; van Bergenhenegouwen, Jeroen; Overbeek, Saskia; van de Kant, Hendrik J. G.; Garssen, Johan; Folkerts, Gert; Vos, Paul; Morgan, Mary E.; Kraneveld, Aletta D.

2014-01-01

144

Runx1-deficient afferents impair visceral nociception, exacerbating dextran sodium sulfate-induced colitis.  

PubMed

Colitis is a group of inflammatory and auto-immune disorders that affect the tissue lining of the gastrointestinal (GI) system. Studies of chemically-induced animal models of colitis have indicated that nociceptive afferents or neuropeptides have differing effects on GI inflammation. However, the molecular mechanisms involved in visceral pain and the role of visceral sensory afferents involved in the modulation of colitis remains unclear. A previous study demonstrated that Runx1, a Runt domain transcription factor, is restricted to nociceptors. In these neurons, Runx1 regulates the expression of numerous ion channels and receptors, controlling the lamina-specific innervation patterns of nociceptive afferents in the spinal cord. Moreover, mice that lack Runx1 exhibit specific defects in thermal and neuropathic pain. To examine the function of Runx1 in visceral nociception, we employed double-transgenic mice (WntCre: Runx1(F)(/)(F)), in which the expression of Runx1 was specifically disrupted in the sensory neurons. To determine the role of Runx1 in visceral pain sensation, the WntCre: Runx1(F)(/)(F) mice and their control littermates (Runx1(F)(/)(F)) were treated using dextran sodium sulfate (DSS) to induce colitis. The results indicated that disrupted Runx1 in the sensory afferents resulted in: (1) impairment of the visceral pain sensation in murine DSS-induced colitis; (2) exacerbating the phenotypes in murine DSS-induced colitis; (3) a differential effect on the production of pro- and anti-inflammatory cytokines in the colon tissues isolated from mice treated using DSS and 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis; and (4) alteration of the distribution of lymphocytes and mast cells in mucosa. These results show that the function of Runx1 in sensory afferents is vital for modulating visceral pain and the neuro-immune axis. PMID:24041578

Hung, Shih-Ping; Sheu, Ming-Jen; Ma, Ming Chieh; Hu, Jui-Ting; Sun, Ya-Yun; Lee, Chin-Cheng; Chung, Yuan-Chiang; Tsai, Yi-Ju; Wang, Jing-Yuan; Chen, Chih-Li

2013-09-13

145

Sodium Dodecyl Sulfate Adsorption onto Positively Charged Surfaces: Monolayer Formation With Opposing Headgroup Orientations  

PubMed Central

The adsorption and structure of sodium dodecyl sulfate (SDS) layers onto positively charged films have been monitored in situ with vibrational sum-frequency-generation (SFG) spectroscopy and surface plasmon resonance (SPR) sensing. Substrates with different charge densities and polarities used in these studies include CaF2 at different pH values as well as allylamine and heptylamine films deposited onto CaF2 and Au substrates by radio frequency glow discharge deposition. The SDS films were adsorbed from aqueous solutions ranging in concentration from 0.067 to 20 mM. In general the SFG spectra exhibited well resolved CH and OH peaks. However, at SDS concentrations between 1–8 mM the SFG CH and OH intensities decreased close to background levels. Combined data sets from molecular conformation, orientation, and order sensitive SFG with mass sensitive SPR suggest that the observed changes in SFG intensities above 0.2 mM are related to structural arrangements in the SDS layer. A model is proposed where the SFG intensity minimum between 1–8 mM is associated with a monolayer containing two head group orientations, one pointing towards the substrate and one pointing towards the solution phase. The SFG peaks observed at concentrations below 0.2 mM are dominated by the presence of adsorbed contaminants such as fatty alcohols (e.g., dodecanol), which are more surface active than SDS. As SDS solution concentration is increased above 1 mM SDS molecules are incorporated in the surface layer, with dodecanol continuing to be present in the surface layer for solution concentrations up to at least critical micelle concentration. PMID:24024777

Song, Sang-Hun; Koelsch, Patrick; Weidner, Tobias; Wagner, Matthew S.; Castner, David G.

2013-01-01

146

Lactococcus lactis subsp. cremoris FC alleviates symptoms of colitis induced by dextran sulfate sodium in mice.  

PubMed

Probiotics have been used to treat human gastrointestinal inflammations including inflammatory bowel disease (IBD). However, the exact mechanisms by which probiotics act to protect against intestinal inflammation have yet to be fully elucidated. The aim of this study was to evaluate anti-inflammatory effects of Lactococcus lactis subsp. cremoris FC using in vivo and in vitro inflammation models. Colitis was induced in C57BL/6 mice by administration of 3% dextran sulfate sodium to drinking water. In the cellular level assessment, a gut inflammation model with the co-culture system consisting Caco-2 cells and RAW264.7 cells stimulated by LPS was used. Administration of L. lactis subsp. cremoris FC significantly ameliorated shortening of colon length and histological score of the colon in DSS-induce colitis mice. In addition, the treatment of L. lactis subsp. cremoris FC improved the aberrant mRNA expression in inflamed tissue near to control level through notable suppression of TNF-alpha (P<0.05), IFN-gamma (P<0.05), IL-6, iNOS, and MIP-2 mRNA expression. In addition, in a gut inflammation model, treatment with L. lactis subsp. cremoris FC resulted in significant down-regulation of IL-8 mRNA expression in Caco-2 cells and inhibition of NF-kappaB nuclear translocation in RAW264.7 cells. Our findings indicate that administration of L. lactis subsp. cremoris FC improves negative effects of DSS-induced colitis in mice through the inhibition of inflammatory cell infiltration. PMID:19733697

Nishitani, Yosuke; Tanoue, Takeshi; Yamada, Katsushige; Ishida, Tsukasa; Yoshida, Masaru; Azuma, Takeshi; Mizuno, Masashi

2009-11-01

147

Porcine ?-Defensin 2 Attenuates Inflammation and Mucosal Lesions in Dextran Sodium Sulfate-Induced Colitis.  

PubMed

Intestinal permeability plays a critical role in the etiopathogenesis of ulcerative colitis. Defensins, including porcine ?-defensin (pBD)2, are crucial antimicrobial peptides for gut protection owing to their antibacterial and immunomodulatory activities. The purpose of this study was to investigate the protective effects of pBD2 on mucosal injury and the disruption of the epithelial barrier during the pathological process of dextran sodium sulfate (DSS)-induced colitis. The effects and mechanism of pBD2 were evaluated both using a DSS-induced C57BL/6 mouse model and, in vitro, using Caco-2 and RAW264.7 cells. DSS-induced colitis was characterized by higher disease activity index, shortened colon length, elevated activities of myeloperoxidase and eosinophil peroxidase, histologic evidence of inflammation, and increased expression levels of TNF-?, IL-6, and IL-8. pBD2 increased the expression of zonula occludens-1, zonula occludens-2, claudin-1, mucin-1, and mucin-2 mRNA and proteins, and it decreased permeability to FITC-D, as well as apoptosis, in DSS-treated mice. pBD2 also decreased inflammatory infiltrates of the colon epithelium. In Caco-2 cells, pBD2 increased transepithelial electrical resistance and mucin mRNA expression, and it decreased the permeability of FITC-D while preserving the structural integrity of the tight junctions. The effects of pBD2 appeared to be through upregulation of the expression of genes associated with tight junctions and mucins, and by suppressing DSS-induced increases in inflammation, inducible NO synthase, cyclooxygenase-2, and apoptosis. These results show that pBD2 improves DSS-induced changes in mucosal lesions and paracellular permeability, possibly by affecting the activation of NF-?B signaling. The present study demonstrates that intrarectal administration of pBD2 may be a novel preventive option for ulcerative colitis. PMID:25601921

Han, Feifei; Zhang, Haiwen; Xia, Xi; Xiong, Haitao; Song, Deguang; Zong, Xin; Wang, Yizhen

2015-02-15

148

Tapeworm Infection Reduces Epithelial Ion Transport Abnormalities in Murine Dextran Sulfate Sodium-Induced Colitis  

PubMed Central

The rat tapeworm Hymenolepis diminuta was used to test the hypothesis that helminth infection could modulate murine colitis. Mice were infected with five H. diminuta cysticercoids, and colitis was evoked via free access to 4% (wt/vol) dextran sulfate sodium (DSS)-containing drinking water for 5 days. BALB/c mice were either infected with H. diminuta and 7 days later exposed to DSS (prophylactic strategy) or started on DSS and infected with H. diminuta 48 h later (treatment strategy). Naive and H. diminuta-only-infected mice served as controls. On autopsy, colonic segments were processed for histological examination and myeloperoxidase (MPO) measurement or mounted in Ussing chambers for assessment of epithelial ion transport. Cytokines (gamma interferon [IFN-?], interleukin 12 [IL-12], and IL-10) were measured in serum and colonic tissue homogenates. DSS treatment resulted in reduced ion responses (indicated by short-circuit current [Isc]) to electrical nerve stimulation, the cholinergic agonist carbachol, and the adenylate cyclase activator forskolin compared to controls. H. diminuta infection, either prophylactic or therapeutic, caused a significant (P < 0.05) amelioration of these DSS-induced irregularities in stimulated ion transport. In contrast, the histopathology (i.e., mixed immune cell infiltrate, edema, and ulcerative damage) and elevated MPO levels that accompany DSS colitis were unaffected by concomitant H. diminuta infection. Similarly, there were no significant differences in levels of IFN-?, IL-12, or IL-10 in serum or tissue from any of the treatment groups at the time of autopsy. We suggest that abolishment of colitis-induced epithelial ion transport abnormalities by H. diminuta infection provides proof-of-principle data and speculate that helminth therapy may provide relief of disease symptoms in colitis. PMID:11401981

Reardon, Colin; Sanchez, Ana; Hogaboam, Cory M.; McKay, Derek M.

2001-01-01

149

Molecular dynamics simulations of sodium dodecyl sulfate micelles in water-the effect of the force field.  

PubMed

Molecular dynamic (MD) simulations of preassembled sodium dodecyl sulfate (SDS) micelles are carried out using three versions of GROMOS, as well as CHARMM36, OPLS-AA, and OPLS-UA force fields at different aggregation numbers and box sizes. The differences among force fields have little effect on the overall micelle structure of small aggregates of size 60 or 100, but for micelles of an aggregation number of 300 or higher, bicelle structures with ordered tails, rather than the more realistic rodlike or cylindrical micelles with disordered tails, occur when using versions of GROMOS45A3 or the OPLS-AA force fields that are adapted to model the sulfate head group atoms using methods given in the literature. We find that the Lennard-Jones (L-J) parameters for the sodium ions and the ionic oxygens of the SDS head group, as well as the water model, control the transition to bicelles, regardless of other L-J parameters. A closer binding of the sodium ions to the head group ionic oxygens screens the electrostatic repulsions more strongly, resulting in condensation of SDS head groups, leading to unphysical bicelles for GROMOS45A3 or the OPLS-AA force fields, when the aggregation number is large. A telltale sign that the sodium-oxygen interaction is too strong shows up in high nearest neighbor peaks (height >8 and height >20 for micelles with 60 and 100 surfactants, respectively) in the radial distribution functions (RDFs) of sodium ions to ionic oxygens. In the 100-surfactant micelles, the high RDF peak is accompanied by "crystal-like" layering of sodium ions onto the surface of the micelle. The distance between the sodium ions and micelle also depends on the number of waters binding to sodium ions in the presence of surfactant head groups, which depends on both the sodium ion and water models, and for the same sodium model increases as the water model is changed in the order: TIP4P, SPC/E, SPC, and TIP3P. PMID:24620851

Tang, Xueming; Koenig, Peter H; Larson, Ronald G

2014-04-10

150

A study of the structure of mixed micellar solutions based on heptaethylene glycol monotetradecyl ether and sodium (lithium) dodecyl sulfate by the small-angle neutron scattering method  

SciTech Connect

The micellization in mixed aqueous systems based on a new nonionic surfactant, namely, heptaethylene glycol monotetradecyl ether (C{sub 14}E{sub 7}), and an anionic surfactant, namely, sodium dodecyl sulfate, sodium decyl sulfate, or lithium dodecyl sulfate, is studied by small-angle neutron scattering. Preliminary results of the investigation into the behavior of C{sub 14}E{sub 7} aqueous solutions (at two concentrations, 0.17 and 0.50%) upon addition of small amounts of three different classical anionic surfactants are reported.

Rajewska, A. [Joint Institute for Nuclear Research (Russian Federation)], E-mail: aldonar@jinr.ru; Medrzycka, K.; Hallmann, E. [Gdansk University of Technology (Poland)

2007-09-15

151

Structural analysis of protein complexes with sodium alkyl sulfates by small-angle scattering and polyacrylamide gel electrophoresis.  

PubMed

Small-angle X-ray (SAXS) and neutron (SANS) scattering is used to probe the structure of protein-surfactant complexes in solution and to correlate this information with their performance in gel electrophoresis. Proteins with sizes between 6.5 to 116 kDa are denatured with sodium alkyl sulfates (SC(x)S) of variable tail lengths. Several combinations of proteins and surfactants are analyzed to measure micelle radii, the distance between micelles, the extension of the complex, the radius of gyration, and the electrophoretic mobility. The structural characterization shows that most protein-surfactant complexes can be accurately described as pearl-necklace structures with spherical micelles. However, protein complexes with short surfactants (SC(8)S) bind with micelles that deviate significantly from spherical shape. Sodium decyl (SC(10)S) and dodecyl (SC(12)S, more commonly abbreviated as SDS) sulfates result in the best protein separations in standard gel electrophoresis. Particularly, SC(10)S shows higher resolutions for complexes of low molecular weight. The systematic characterization of alkyl sulfate surfactants demonstrates that changes in the chain architecture can significantly affect electrophoretic migration so that protein-surfactant structures could be optimized for high resolution protein separations. PMID:21182321

Ospinal-Jiménez, Mónica; Pozzo, Danilo C

2011-02-01

152

Solubilization of Aliphatic Carboxylic Acids (C3-C6) by Sodium Dodecyl Sulfate and Brij 35 Micellar Pseudophases  

Microsoft Academic Search

The apparent dissociation constants of 1-propanoic, 1-butanoic, 1-pentanoic and 1-hexanoic acids were obtained for the first\\u000a time in Brij 35 micellar solutions with concentration from 0.03 to 0.20 mol?L?1 and sodium dodecyl sulfate (SDS) micellar solutions with concentrations from 0.01 to 0.30 mol?L?1. A pronounced effect of Brij 35 micelles on the acid-base properties of aliphatic acids was observed. The binding constants,

Alexander P. Boichenko; Le Thi Kim Dung; Lidia P. Loginova

2011-01-01

153

Electrochemical measurements on the binding of sodium dodecyl sulfate and dodecyltrimethylammonium bromide with {alpha}- and {beta}-cyclodextrins  

SciTech Connect

The binding of ionic surfactants (S) to {alpha}- and {beta}-cyclodextrins (CD) has been investigated using surfactant-selective electrodes. These electrochemical measurements have shown that S(CD) and S(CD){sub 2} inclusion complexes are formed between sodium dodecyl sulfate and both {alpha}- and {beta}-cyclodextrins and also between dodecyltrimethylammonium bromide and {alpha}-cyclodextrin. On the other hand, the cationic surfactant only forms a 1:1 complex with {beta}-cyclodextrin. From the data the equilibrium binding constants for the formation of each of the complexes have been evaluated. 29 refs., 5 figs., 1 tab.

Wan Yunus, W.M.Z.; Taylor, J.; Bloor, D.M.; Hall, D.G.; Wyn-Jones, E. [Univ. of Salford (United Kingdom)

1992-10-29

154

The effects of sodium sulfate in the water of nursery pigs and the efficacy of nonnutritive feed additives to mitigate those effects.  

PubMed

Two experiments were conducted to investigate the effects of sodium sulfate water and the efficacy of nonnutritive feed additives in nursery pig diets. In Exp. 1, 320 barrows (5.4 ± 0.1 kg BW and 21 d of age) were allotted to 1 of 8 treatments for 24 d in a 2 × 4 factorial with 2 levels of sodium sulfate water (control or 3,000 mg sodium sulfate/L added), and 4 dietary zeolite (clinoptilolite) levels (0, 0.25, 0.50, or 1%). Fecal samples were collected on d 5, 9, 16, and 23; visually scored for consistency (1 = firm and 5 = watery); and analyzed for DM. No interactions of sodium sulfate × zeolite were observed for any response criteria. Overall (d 0 to 24), pigs drinking sodium sulfate water had decreased (P < 0.01) ADG, ADFI, and G:F compared with pigs drinking control water. Pigs drinking sodium sulfate water also had increased (P < 0.01) fecal scores and lower (P < 0.04) fecal DM on d 5, 9, and 16 compared with pigs drinking control water. Increasing dietary zeolite increased (linear; P < 0.05) ADG and ADFI but had no effect on G:F. In Exp. 2, 350 barrows (5.7 ± 0.1 kg BW and 21 d of age) were allotted to 1 of 10 treatments in a 2 × 5 factorial for 21 d with 2 levels of sodium sulfate water (control or 2,000 mg sodium sulfate/L added) and 5 dietary treatments (control, 1 or 2% zeolite, 1% humic acid substance [HA], and 1% humic and fulvic acid substance [HFB]). Fecal samples were collected on d 5, 8, 15, and 21; visually scored for consistency (1 = firm and 5 = watery); and analyzed for DM. Overall (d 0 to 21), a water source × diet interaction was observed for ADG and G:F because pigs fed the 1% HA had decreased (P < 0.01) ADG and G:F when drinking sodium sulfate water compared with other treatments but increased ADG and G:F when drinking control water. Pigs drinking sodium sulfate water had decreased (P < 0.01) ADG and G:F and tended (P < 0.08) to have decreased ADFI compared with pigs drinking control water. Pigs drinking sodium sulfate water had increased (P < 0.01) fecal scores and decreased (P < 0.01) fecal DM on d 5 and 8. In conclusion, water high in sodium sulfate concentrations decreased growth performance and increased fecal moisture in newly weaned pigs. Although zeolite improved growth performance in the first experiment, it did not influence growth in the second study. The nonnutritive feed additives used in both experiments were unsuccessful in ameliorating the increased osmotic diarrhea observed from high sodium sulfate water. PMID:24981569

Flohr, J R; Tokach, M D; Dritz, S S; DeRouchey, J M; Goodband, R D; Nelssen, J L

2014-08-01

155

Formation of Reactive Sulfite-Derived Free Radicals by the Activation of Human Neutrophils: An ESR Study  

PubMed Central

The objective of the present study is to determine the effect of (bi)sulfite (hydrated sulfur dioxide) on human neutrophils and the ability of these immune cells to produce reactive free radicals due to (bi)sulfite oxidation. Myeloperoxidase (MPO) is an abundant heme protein in neutrophils that catalyzes the formation of cytotoxic oxidants implicated in asthma and inflammatory disorders. In the present study sulfite (•SO3?) and sulfate (SO4•?) anion radicals are characterized with the ESR spin-trapping technique using 5,5-dimethyl-1-pyrroline N-oxide (DMPO) in the reaction of (bi)sulfite oxidation by human MPO and human neutrophils via sulfite radical chain reaction chemistry. After treatment with (bi)sulfite, PMA-stimulated neutrophils produced DMPO-sulfite anion radical, -superoxide, and -hydroxyl radical adducts. The latter adduct probably resulted, in part, from the conversion of DMPO-sulfate to DMPO-hydroxyl radical adduct via a nucleophilic substitution reaction of the radical adduct. This anion radical (SO4•?) is highly reactive and, presumably, can oxidize target proteins to protein radicals, thereby initiating protein oxidation. Therefore, we propose that the potential toxicity of (bi)sulfite during pulmonary inflammation or lung-associated diseases such as asthma may be related to free radical formation. PMID:22326772

Ranguelova, Kalina; Rice, Annette B.; Khajo, Abdelahad; Triquigneaux, Mathilde; Garantziotis, Stavros; Magliozzo, Richard S.; Mason, Ronald P.

2012-01-01

156

Effect of crown ether 1,4,7,10,13,16-hexaoxacyclooctadecane on the structure of sodium dodecyl sulfate and dodecyltrimethylammonium bromide aqueous micellar solutions  

SciTech Connect

The effects of the addition of crown ether 1,4,7,10,13,16-hexaoxacyclooctadecane on the structure of aqueous solutions of surfactants sodium dodecyl sulfate and dodecyltrimethylammonium bromide have been studied by small angle neutron scattering. In the case of sodium dodecyl sulfate, an appreciable amount of crown ether was found to be localized in the micellar phase, though it was not possible to establish whether it was in the core or in the shell; there was no evidence of crown ether localization in dodecyltrimethylammonium bromide micelles. The above observations indicate that although, at least in principle, the crown ether methylene groups could interact hydrophobically in the micellar core with the surfactant alkyl chains, the ability of crown ethers to form metal complexes might also lead, in sodium dodecyl sulfate solutions, to electrostatic interactions in the external palisade between the crown ether-sodium ion complex and the surfactant head groups. The absence of crown ether from dodecyltrimethylammonium bromide micelles indicates that the macrocyclic molecules interact with sodium dodecyl sulfate micelles via the formation of a complex between the sodium ion and the crown ether and rules out the possibility of hydrophobic interaction in the micellar core. 40 refs., 8 figs., 3 tabs.

Caponetti, E.; Martino, D.C.; Floriano, M.A. [Universita di Palermo (Italy); Triolo, R.; Wignall, G.D. [Oak Ridge National Lab., TN (United States)

1995-07-01

157

Oxidation inhibition of sulfite in dual alkali flue gas desulfurization system  

Microsoft Academic Search

A laboratory-scale well-mixed thermostatic reactor with continuously blasting air was used to investigate the oxidation inhibition of sulfite in dual alkali flue gas desulfurization (FGD) system. The effects of operating parameters such as pH value and catalyst concentration on the oxidation were studied. Sodium thiosulfate was used in the system, and was found that it significantly inhabited the sulfite oxidation.

Jian-song MO; Zhong-biao WU; Chang-jie CHENG; Bao-hong GUAN; Wei-rong ZHAO

2007-01-01

158

Stopped-flow kinetic studies of sphere-to-rod transitions of sodium alkyl sulfate micelles induced by hydrotropic salt.  

PubMed

The kinetics and mechanism of sphere-to-rod transitions of sodium alkyl sulfate micelles induced by hydrotropic salt, p-toluidine hydrochloride (PTHC), were investigated by stopped-flow with light scattering detection. Spherical sodium dodecyl sulfate (SDS) micelles transform into short ellipsoidal shapes at low salt concentrations ([PTHC]/[SDS], chi(PTHC)=0.3 and 0.4). Upon stopped-flow mixing aqueous solutions of spherical SDS micelles with PTHC, the scattered light intensity gradually increases with time. Single exponential fitting of the dynamic traces leads to characteristic relaxation time, tau(g), for the growth process from spherical to ellipsoidal micelles, and it increases with increasing SDS concentrations. This suggests that ellipsoidal micelles might be produced by successive insertion of unimers into spherical micelles, similar to the case of formation of spherical micelles as suggested by Aniansson-Wall (A-W) theory. At chi(PTHC) > or = 0.5, rod-like micelles with much higher axial ratio form. The scattered light intensity exhibits an initially abrupt increase and then levels off. The dynamic curves can be well fitted with single exponential functions, and the obtained tau(g) decreases with increasing SDS concentration. Thus, the growth from spherical to rod-like micelles might proceed via fusion of spherical micelles, in agreement with mechanism proposed by Ikeda et al. At chi(PTHC)=0.3 and 0.6, the apparent activation energies obtained from temperature dependent kinetic studies for the micellar growth are 40.4 and 3.6 kJ/mol, respectively. The large differences between activation energies for the growth from spherical to ellipsoidal micelles at low chi(PTHC) and the sphere-to-rod transition at high chi(PTHC) further indicate that they should follow different mechanisms. Moreover, the sphere-to-rod transition kinetics of sodium alkyl sulfate with varying hydrophobic chain lengths (n=10, 12, 14, and 16) are also studied. The longer the carbon chain lengths, the slower the sphere-to-rod transition. PMID:17904570

Zhang, Jingyan; Ge, Zhishen; Jiang, Xiaoze; Hassan, P A; Liu, Shiyong

2007-12-15

159

Immunological comparison of sulfite oxidase  

SciTech Connect

Polyclonal antibodies (rabbit), elicited against FPLC-purified chicken and rat liver sulfite oxidase (SO), have been examined for inhibition and binding to purified chicken (C), rat (R), bovine (B), alligator (A) and shark (S) liver enzymes. Anti-CSO IgG cross-reacted with all five enzymes, with varying affinities, in the order CSO=ASO{gt}RSO{gt}BSO{gt}SSO. Anti-ROS IgG also cross-reacted with all five enzymes in the order RSO{gt}CSO=ASO{gt}BSO{gt}SSO. Anti-CSO IgG inhibited sulfite:cyt. c reductase (S:CR), sulfite:ferricyanide reductase (S:FR) and sulfite:dichlorophenolindophenol reductase (S:DR) activities of CSO to different extents (S:CR{gt}S:FR=S:DR). Similar differential inhibition was found for anti-ROS IgG and RSO S:CR, S:FR and S:DR activities. Anti-CSO IgG inhibited S:CR activities in the order CSO=ASO{much gt}SSO{gt}BSO. RSO was uninhibited. For anti-RSO IgG the inhibition order was RSO{gt}SSO{gt}BSO{gt}ASO. CSO was uninhibited. Anti-CSO and RSO IgGs partially inhibited Chlorella nitrate reductase (NR). Minor cross-reactivity was found for xanthine oxidase. Common antigenic determinants for all five SO's and NR are indicated.

Pollock, V.; Barber, M.J. (Univ. South Florida College, Tampa (United States))

1991-03-11

160

Determination of vegetal proteins in milk powder by sodium dodecyl sulfate-capillary gel electrophoresis: interlaboratory study.  

PubMed

An interlaboratory study, with the participation of 8 laboratories, was conducted to evaluate a sodium dodecyl sulfate-capillary gel electrophoresis method for determination of adulteration of milk powder with soy and pea proteins. Calibration standards (0-8%, w/w, soy and pea protein in total protein) and adulterated skim milk powders (0-5%, w/w, soy and pea proteins in total protein) were produced. Vegetal proteins were determined after removal of milk proteins by pretreatment of the samples with tetraborate-EDTA buffer, pH 8.3. Repeatability standard deviations ranged from 9 to 15% and reproducibility standard deviations ranged from 25 to 30% in the samples containing 5% vegetal protein in total protein. PMID:12374408

Manso, María A; Cattaneo, Tiziana Maria; Barzaghi, Stefania; Olieman, Cornelis; López-Fandiño, Rosina

2002-01-01

161

Comparative study of photoluminescence of single-walled carbon nanotubes wrapped with sodium dodecyl sulfate, surfactin and polyvinylpyrrolidone  

NASA Astrophysics Data System (ADS)

Single-walled carbon nanotubes (SWCNTs) have been dispersed with three types of amphiphilic materials in aqueous solutions: (i) an anionic aliphatic surfactant, sodium dodecyl sulfate (SDS), (ii) a cyclic lipopeptide biosurfactant, surfactin, and (iii) a water-soluble polymer, polyvinylpyrrolidone (PVP). Solution photoluminescence (PL) studies suggest that SDS wrapping is very sensitive to the temperature whereas the other two give relatively robust wrapping around the SWCNTs. Low temperature PL spectra from both surfactin and PVP dispersed SWCNTs show that peak shifts are strongly dependent on their chiralities, which can be explained by the bandgap modulations with the environmental strain. The uniaxial and torsional strains deduced from their bandgap shifts were similar, indicating the strains are mainly due to the different rates of thermal expansion in SWCNTs and ice.

Li, Lain-Jong; Nicholas, R. J.; Chen, Chien-Yen; Darton, R. C.; Baker, S. C.

2005-05-01

162

Curvature effects on the adsorption of aqueous sodium-dodecyl-sulfate surfactants on carbonaceous substrates: structural features and counterion dynamics.  

PubMed

The effect of substrate curvature on surfactant self-assembly has been studied using all-atom molecular-dynamics simulations. We studied aqueous sodium-dodecyl-sulfate (SDS) surfactants on graphite, on the outer surface of single walled carbon nanotubes (SWNTs) and within SWNTs. Our results reveal that although the chemical nature of the substrates is constant, the self-assembled structures change significantly as the curvature varies. For example, at large surface density, SDS surfactants yield micellar structures on graphite, layered self-assemblies outside SWNTs, and cylindrical lamellar structures inside SWNTs. Changes in substrate curvature as well as surfactant surface density affect significantly surfactant orientation and, more importantly, headgroup-headgroup distribution, headgroup-counterion packing, and counterion residence time next to the headgroups. PMID:19792125

Tummala, Naga Rajesh; Striolo, Alberto

2009-08-01

163

Structure of the sodium dodecyl sulfate surfactant on a solid surface in different NaCl solutions.  

PubMed

Studies of molecular dynamics simulations of sodium dodecyl sulfate (SDS) molecules adsorbed on a graphite surface in different salt (NaCl)/water solutions were conducted. The results showed the formation of hemicylindrical aggregates, at different salt concentrations, in agreement with atomic force microscopy (AFM) results. However, the hemicylinders exhibited different structures as the salt concentration was increased. At low concentrations, the internal structure of the hemicylinder formed well-defined SDS layers, parallel to the surface. However, when the amount of salt was increased, the top layer became less pronounced until it disappeared at the highest concentration. Density profiles of the SDS headgroups were also analyzed, and those profiles were found to become sharper as the NaCl concentration increased. The phenomenon was investigated in terms of how the aggregates wet the solid surface. PMID:19719216

Domínguez, Hector

2009-08-18

164

Adiabatic polymerization of acrylamide in water under the effect of the potassium persulfate-sodium metabisulfite-copper sulfate system  

SciTech Connect

Since adiabatic polymerization of acrylamide (AA) has been studied very little and the information on the effect of copper ions on polymerization of AA prepared in dilute aqueous solutions is very limited, the features of adiabatic polymerization of AA in concentrated aqueous solutions in the presence of the potassium persulfate-sodium metabisulfite-copper sulfate redox initiating system were investigated in this study. The empirical equation for the overall rate of adiabatic polymerization of acrylamide in concentrated aqueous solutions was found, and the effective total activation energy, which decreases with an increase in the concentration of CuSO/sub 4/, was determined. An increase in the molecular weight of the polymer with an increase in the concentration of the monomer and a decrease in the concentration of the components of the initiating system was demonstrated.

Kurenkov, V.F.; Baiburdov, T.A.; Stupen'kova, L.L.

1988-04-10

165

Mixed layers of sodium caseinate + dextran sulfate: influence of order of addition to oil-water interface.  

PubMed

We report on the interfacial properties of electrostatic complexes of protein (sodium caseinate) with a highly sulfated polysaccharide (dextran sulfate). Two routes were investigated for preparation of adsorbed layers at the n-tetradecane-water interface at pH = 6. Bilayers were made by the layer-by-layer deposition technique whereby polysaccharide was added to a previously established protein-stabilized interface. Mixed layers were made by the conventional one-step method in which soluble protein-polysaccharide complexes were adsorbed directly at the interface. Protein + polysaccharide systems gave a slower decay of interfacial tension and stronger dilatational viscoelastic properties than the protein alone, but there was no significant difference in dilatational properties between mixed layers and bilayers. Conversely, shear rheology experiments exhibited significant differences between the two kinds of interfacial layers, with the mixed system giving much stronger interfacial films than the bilayer system, i.e., shear viscosities and moduli at least an order of magnitude higher. The film shear viscoelasticity was further enhanced by acidification of the biopolymer mixture to pH = 2 prior to interface formation. Taken together, these measurements provide insight into the origin of previously reported differences in stability properties of oil-in-water emulsions made by the bilayer and mixed layer approaches. Addition of a proteolytic enzyme (trypsin) to both types of interfaces led to a significant increase in the elastic modulus of the film, suggesting that the enzyme was adsorbed at the interface via complexation with dextran sulfate. Overall, this study has confirmed the potential of shear rheology as a highly sensitive probe of associative electrostatic interactions and interfacial structure in mixed biopolymer layers. PMID:19459686

Jourdain, Laureline S; Schmitt, Christophe; Leser, Martin E; Murray, Brent S; Dickinson, Eric

2009-09-01

166

An Essential Role for Tomato Sulfite Oxidase and Enzymes of the Sulfite Network in Maintaining Leaf Sulfite Homeostasis1[W][OA  

PubMed Central

Little is known about the homeostasis of sulfite levels, a cytotoxic by-product of plant sulfur turnover. By employing extended dark to induce catabolic pathways, we followed key elements of the sulfite network enzymes that include adenosine-5?-phosphosulfate reductase and the sulfite scavengers sulfite oxidase (SO), sulfite reductase, UDP-sulfoquinovose synthase, and ?-mercaptopyruvate sulfurtransferases. During extended dark, SO was enhanced in tomato (Solanum lycopersicum) wild-type leaves, while the other sulfite network components were down-regulated. SO RNA interference plants lacking SO activity accumulated sulfite, resulting in leaf damage and mortality. Exogenous sulfite application induced up-regulation of the sulfite scavenger activities in dark-stressed or unstressed wild-type plants, while expression of the sulfite producer, adenosine-5?-phosphosulfate reductase, was down-regulated. Unstressed or dark-stressed wild-type plants were resistant to sulfite applications, but SO RNA interference plants showed sensitivity and overaccumulation of sulfite. Hence, under extended dark stress, SO activity is necessary to cope with rising endogenous sulfite levels. However, under nonstressed conditions, the sulfite network can control sulfite levels in the absence of SO activity. The novel evidence provided by the synchronous dark-induced turnover of sulfur-containing compounds, augmented by exogenous sulfite applications, underlines the role of SO and other sulfite network components in maintaining sulfite homeostasis, where sulfite appears to act as an orchestrating signal molecule. PMID:23148079

Brychkova, Galina; Grishkevich, Vladislav; Fluhr, Robert; Sagi, Moshe

2013-01-01

167

Acids in combination with sodium dodecyl sulfate caused quality deterioration of fresh-cut iceburg lettuce during storage in modified atmosphere package  

Technology Transfer Automated Retrieval System (TEKTRAN)

Recent studies showed that levulinic acid (LA) and sodium acid sulfate (SAS) were effective in inactivating human pathogens on fresh produce. The present study investigated the effects of LA and SAS in comparison with citric acid and chlorine on the inactivation of E. coli O157:H7 and the sensory qu...

168

A novel, environmentally friendly sodium lauryl ether sulfate-, cocamidopropyl betaine-, cocamide monoethanolamine-containing buffer for MEKC on microfluidic devices.  

PubMed

A new buffer has been developed for fast, high-efficiency separations of amino acids by MEKC. This buffer was more environmentally friendly than the most commonly used surfactant-containing buffers for MEKC separations. It used a commercially available dishwashing soap by Seventh Generation (Burlington, VT, USA), which contained three micelle-forming agents. The mixed micelles were composed of sodium lauryl ether sulfate (anionic), cocamidopropyl betaine (zwitterionic), and cocamide monoethanolamine (non-ionic). The optimized buffer contained 5.0% w/w Seventh Generation Free & Clear dishwashing soap, 10 mM sodium borate, and was completely void of organics. The lack of organics and the biodegradability of the surfactant molecules made this buffer more environmentally friendly than typical SDS-containing buffers. This new buffer also had a different selectivity and provided faster separations with higher separation efficiencies than SDS-based buffers. Fast separations of BODIPY FL labeled amino acids yielded peaks with separation efficiencies greater than 100,000 in less than 20 s. PMID:19130569

Hoeman, Kurt W; Culbertson, Christopher T

2008-12-01

169

Thermodynamic study of the n-octane-1-pentanol-sodium dodecyl sulfate solutions in water  

Microsoft Academic Search

The thermodynamic properties, PVTx (TS, PS, ?S), (?P\\/?T)VX, and CVVTx, of three microemulsions (water+n-octane+sodium dodecylsulfate+1-pentanol) with composition of solution-1: 0.0777 (H2O):0.6997 (n-C8H18):0.0777 (SDS):0.1449 (1-C5H11OH) mass fraction; solution-2: 0.6220 (H2O):0.1555 (n-C8H18):0.0777 (SDS):0.1448 (1-C5H11OH) mass fraction; and solution-3: 0.2720 (H2O):0.5054 (n-C8H18):0.0777 (SDS):0.1449 (1-C5H11OH) mass fraction were measured. Sodium dodecylsulfate (SDS) was used as an ionic surfactant, 1-pentanol used as stabilizer (cosurfactant), and

Nikolai G. Polikhronidi; Genadii V. Stepanov; Ilmutdin M. Abdulagatov; Rabiyat G. Batyrova

2007-01-01

170

Sulfite (SPORL) pretreatment of switchgrass for enzymatic saccharification.  

PubMed

SPORL (Sulfite Pretreatment to Overcome Recalcitrance of Lignocellulose) pretreatment was applied to switchgrass and optimized through an experimental design using Response Surface Methodology within the range of temperature (163-197 °C), time (3-37 min), sulfuric acid dosage (0.8-4.2% on switchgrass), and sodium sulfite dosage (0.6-7.4% on switchgrass). Performance of SPORL was compared with that of dilute acid (DA) and alkali (AL) in switchgrass pretreatment. Results indicated that SPORL pretreatment improved the digestibility of switchgrass through sufficiently removing hemicellulose, partially dissolving lignin, and reducing hydrophobicity of lignin by sulfonation. The removal of hemicellulose was more critical to substrate digestibility than the removal of lignin during SPORL pretreatment. SPORL pretreated switchgrass had better enzymatic digestibility than DA and AL pretreated ones. The SPORL pretreated switchgrass could be hydrolyzed by 83% within 48 h with 15 FPU (filter paper unit) cellulase and 30 CBU (cellobiose unit) ?-glucosidase/g cellulose. PMID:23232228

Zhang, D S; Yang, Q; Zhu, J Y; Pan, X J

2013-02-01

171

The optical constants of several atmospheric aerosol species - Ammonium sulfate, aluminum oxide, and sodium chloride  

NASA Technical Reports Server (NTRS)

An investigation is conducted of problems which are related to a use of measured optical constants in the simulation of the optical constants of real atmospheric aerosols. The techniques of measuring optical constants are discussed, taking into account transmission measurements through homogeneous and inhomogeneous materials, the immersion of a material in a liquid of a known refractive index, the consideration of the minimum deviation angle of prism measurement, the interference of multiply reflected light, reflectivity measurements, and aspects of mathematical analysis. Graphs show the real and the imaginary part of the refractive index as a function of wavelength for aluminum oxide, NaCl, and ammonium sulfate. Tables are provided for the dispersion parameters and the optical constants.

Toon, O. B.; Pollack, J. B.; Khare, B. N.

1976-01-01

172

Adhesion of sodium dodecyl sulfate surfactant monolayers with TiO2 (rutile and anatase) surfaces  

SciTech Connect

Surfactants are widely used as templates to control the nucleation and growth of nanostructured metal oxides such as titania. To gain insight into the origin of surfactant-titania interactions responsible for polymorph and orientation selection, we simulate the self-assembly of an anionic surfactant monolayer on various low-index titania surfaces and for a range of densities. We characterize the binding in each case and compute the adhesion energies, finding anatase (100) and rutile (110) to be the strongest-binding surfaces. The sodium counterions in the monolayer are found to dominate the adhesion. It is also observed that the assembly is directed predominantly by surface-monolayer electrostatic complementarity.

Darkins, Robert; Sushko, Maria L.; Liu, Jun; Duffy, Dorothy M.

2013-09-17

173

Liquid-liquid phase separation in particles containing organics mixed with ammonium sulfate, ammonium bisulfate, ammonium nitrate or sodium chloride  

NASA Astrophysics Data System (ADS)

As the relative humidity varies from high to low values in the atmosphere, particles containing organic species and inorganic salts may undergo liquid-liquid phase separation. The majority of the laboratory work on this subject has used ammonium sulfate as the inorganic salt. In the following we studied liquid-liquid phase separation in particles containing organics mixed with the following salts: ammonium sulfate, ammonium bisulfate, ammonium nitrate and sodium chloride. In each experiment one organic was mixed with one inorganic salt and the liquid-liquid phase separation relative humidity (SRH) was determined. Since we studied 23 different organics mixed with four different salts, a total of 92 different particle types were investigated. Out of the 92 types, 49 underwent liquid-liquid phase separation. For all the inorganic salts, liquid-liquid phase separation was never observed when the oxygen-to-carbon elemental ratio (O : C) ≥ 0.8 and was always observed for O : C < 0.5. For 0.5 ≤ O : C < 0.8, the results depended on the salt type. Out of the 23 organic species investigated, the SRH of 20 organics followed the trend: (NH4)2SO4 ≥ NH4HSO4 ≥ NaCl ≥ NH4NO3. This trend is consistent with previous salting out studies and the Hofmeister series. Based on the range of O : C values found in the atmosphere and the current results, liquid-liquid phase separation is likely a frequent occurrence in both marine and non-marine environments.

You, Y.; Renbaum-Wolff, L.; Bertram, A. K.

2013-12-01

174

Kinetics of oxidation of total sulfite in the ammonia-based wet flue gas desulfurization process  

Microsoft Academic Search

Using bubbling apparatus, the kinetics of oxidation of total sulfite in ammonia-based wet flue gas desulfurization (FGD) process was investigated by varying concentrations of SO32? and SO42?, pH, temperatures and air flow. The concentration range of sulfite is 0.0044–0.026gmolL?1 and that of sulfate is 0.5–2gmolL?1. Experiments were conducted at pH level of 4.5–6.5 and air flow ranging from 50 to

Yong Jia; Qin Zhong; Xueyou Fan; Xinrong Wang

2010-01-01

175

Use of sulfate reducing cell suspension bioreactors for the treatment of SO2 rich flue gases.  

PubMed

This paper describes a novel bioscrubber concept for biological flue gas desulfurization, based on the recycling of a cell suspension of sulfite/sulfate reducing bacteria between a scrubber and a sulfite/sulfate reducing hydrogen fed bioreactor. Hydrogen metabolism in sulfite/sulfate reducing cell suspensions was investigated using batch activity tests and by operating a completely stirred tank reactor (CSTR). The maximum specific hydrogenotrophic sulfite/sulfate reduction rate increased with 10% and 300%, respectively, by crushing granular inoculum sludge and by cultivation of this sludge as cell suspension in a CSTR. Operation of a sulfite fed CSTR (hydraulic retention time 4 days; pH 7.0; sulfite loading rate 0.5-1.5 g SO3(2-) l(-1) d(-1)) with hydrogen as electron donor showed that high (up to 1.6 g l(-1)) H2S concentrations can be obtained within 10 days of operation. H2S inhibition, however, limited the sulfite reducing capacity of the CSTR. Methane production by the cell suspension disappeared within 20 days reactor operation. The outcompetition of methanogens in excess of H2 can be attributed to CO2 limitation and/or to sulfite or sulfide toxicity. The use of cell suspensions opens perspectives for monolith or packed bed reactor configurations, which have a much lower pressure drop compared to air lift reactors, to supply H2 to sulfite/sulfate reducing bioreactors. PMID:12889613

Lens, P N L; Gastesi, R; Lettinga, G

2003-06-01

176

Sulfite-Mediated Oxidation of Myeloperoxidase to a Free Radical: Immuno-Spin Trapping Detection in Human Neutrophils  

PubMed Central

Previous studies focused on catalyzed oxidation of (bi)sulfite, leading to the formation of reactive sulfur trioxide (•SO3?), peroxymonosulfate (?O3SOO•) and sulfate (SO4•?) anion radicals, which can damage target proteins and oxidize them to protein radicals. It is known that these very reactive sulfur- and oxygen-centered radicals can be formed by oxidation of (bi)sulfite by peroxidases. Myeloperoxidase (MPO), an abundant heme protein secreted from activated neutrophils that play a central role in host defense mechanisms, allergic reactions and asthma, is a likely candidate for initiating the respiratory damage caused by sulfur dioxide. The objective of the present study is to examine the oxidative damage caused by (bi)sulfite-derived free radicals in human neutrophils through formation of protein radicals. We used immuno-spin trapping and confocal microscopy to study the protein oxidations driven by sulfite-derived radicals. We found that the presence of sulfite can cause MPO-catalyzed oxidation of MPO to a protein radical in phorbol 12-myristate 13-acetate (PMA)-activated human neutrophils. We trapped the MPO-derived radicals in situ using the nitrone spin trap 5,5-dimethyl-1-pyrroline N-oxide (DMPO) and detected them immunologically as nitrone adducts in cells. Our present study demonstrates that myeloperoxidase initiates (bi)sulfite oxidation leading to MPO radical damage possibly leading to (bi)sulfite-exacerbated allergic reactions. PMID:23376232

Ranguelova, Kalina; Rice, Annette B.; Lardinois, Olivier M.; Triquigneaux, Mathilde; Steinckwich, Natacha; Deterding, Leesa J.; Garantziotis, Stavros; Mason, Ronald P.

2013-01-01

177

Oxidation of metal sulfites by iodine for use in thermochemical hydrogen cycles  

NASA Astrophysics Data System (ADS)

It is noted that thermochemical hydrogen cycles involving metal sulfates offer an alternative to sulfuric acid which is corrosive and has high energy requirements for drying prior to its thermal decomposition. The formation of such metal sulfates in conjunction with a low temperature hydrogen formation step is discussed. The following reaction was studied: MgSO3(c) + MgO(c) + I2(g) yields MgSO4(c) + MgI2(c). Although magnesium sulfite appears promising for this oxidation, a search was conducted for alternative metal sulfites which fit the following criteria for use: (1) sulfate must decompose in the temperature range available ( 1400 K); (2) iodide must hydrolyze easily; and (3) salts must not be rare, toxic, or expensive. Lanthanum and titanium fit these criteria.

Mason, C. F. V.; Bowman, M. G.

1981-09-01

178

Skin deposition and permeation of finasteride in vitro: effects of propylene glycol, ethanol and sodium lauryl sulfate.  

PubMed

Abstract The objective of this study was to investigate the effects of propylene glycol (PG), ethanol (EtOH) and sodium lauryl sulfate (SLS) on the in vitro deposition and permeation of finasteride (FNS). A side-by-side diffusion cell mounted with a pig ear skin and a saturated solution of FNS in PG (10, 20%?v/v), EtOH (10, 20%?v/v) or SLS (0.5, 1%?w/v) vehicles were used. Incorporation of PG, EtOH or SLS caused a significant increase in FNS solubility both in the solution and on the skin with SLS?>?EtOH?>?PG. The results obtained from skin deposition studies showed that the FNS deposition rate and time increased in the same order as that of the solubility. The deposition kinetics of FNS solubilized in PG, EtOH and SLS vehicles followed either zero-order, square-root-of-time or pseudo-first-order kinetic models depending on the type and concentration of the enhancer. The permeation studies demonstrated that FNS permeation fluxes were enhanced only by EtOH vehicles. These results suggest that PG and SLS could be used as deposition enhancers, while EtOH could be the effective permeation enhancer of FNS. The obtained results can be used as the considerable insights for formulating the topical and transdermal products of FNS. PMID:25162771

Limpongsa, Ekapol; Jaipakdee, Napaphak; Pongjanyakul, Thaned

2014-08-27

179

Monocolonization of Germ-Free Mice with Bacteroides fragilis Protects against Dextran Sulfate Sodium-Induced Acute Colitis  

PubMed Central

Ulcerative colitis is inflammatory conditions of the colon caused by interplay of genetic and environmental factors. Previous studies indicated that the gut microflora may be involved in the colonic inflammation. Bacteroides fragilis (BF) is a Gram-negative anaerobe belonging to the colonic symbiotic. We aimed to investigate the protective role of BF in a colitis model induced in germ-free (GF) mice by dextran sulfate sodium (DSS). GF C57BL/6JNarl mice were colonized with BF for 28 days before acute colitis was induced by DSS. BF colonization significantly increased animal survival by 40%, with less reduction in colon length, and decreased infiltration of inflammatory cells (macrophages and neutrophils) in colon mucosa following challenge with DSS. In addition, BF could enhance the mRNA expression of anti-inflammatory-related cytokine such as interleukin 10 (IL-10) with polymorphism cytokine IL-17 and diminish that of proinflammatory-related tumor necrosis factor ? with inducible nitric oxide synthase in the ulcerated colon. Myeloperoxidase activity was also decreased in BF-DSS mice. Taking these together, the BF colonization significantly ameliorated DSS-induced colitis by suppressing the activity of inflammatory-related molecules and inducing the production of anti-inflammatory cytokines. BF may play an important role in maintaining intestinal immune system homeostasis and regulate inflammatory responses. PMID:24971344

Liu, Ju-Yun; Li, Yen-Peng; Huang, Yen-Te; Chuang, Hsiao-Li

2014-01-01

180

Hexavalent molybdenum reduction to mo-blue by a sodium-dodecyl-sulfate-degrading Klebsiella oxytoca strain DRY14.  

PubMed

Bacteria with the ability to tolerate, remove, and/or degrade several xenobiotics simultaneously are urgently needed for remediation of polluted sites. A previously isolated bacterium with sodium dodecyl sulfate- (SDS-) degrading capacity was found to be able to reduce molybdenum to the nontoxic molybdenum blue. The optimal pH, carbon source, molybdate concentration, and temperature supporting molybdate reduction were pH 7.0, glucose at 1.5% (w/v), between 25 and 30?mM, and 25°C, respectively. The optimum phosphate concentration for molybdate reduction was 5?mM. The Mo-blue produced exhibits an absorption spectrum with a maximum peak at 865 nm and a shoulder at 700?nm. None of the respiratory inhibitors tested showed any inhibition to the molybdenum-reducing activity suggesting that the electron transport system of this bacterium is not the site of molybdenum reduction. Chromium, cadmium, silver, copper, mercury, and lead caused approximately 77, 65, 77, 89, 80, and 80% inhibition of the molybdenum-reducing activity, respectively. Ferrous and stannous ions markedly increased the activity of molybdenum-reducing activity in this bacterium. The maximum tolerable concentration of SDS as a cocontaminant was 3?g/L. The characteristics of this bacterium make it a suitable candidate for molybdenum bioremediation of sites cocontaminated with detergent pollutant. PMID:24383052

Halmi, M I E; Zuhainis, S W; Yusof, M T; Shaharuddin, N A; Helmi, W; Shukor, Y; Syed, M A; Ahmad, S A

2013-01-01

181

Increased Susceptibility to Dextran Sulfate Sodium-Induced Colitis in the Endoplasmic Reticulum Stress Transducer OASIS Deficient Mice  

PubMed Central

OASIS is a basic leucine zipper (bZIP) transmembrane transcription factor that is activated in response to endoplasmic reticulum (ER) stress. Previously, we showed that OASIS regulates final maturation of goblet cells in the large intestine. In the present study, to elucidate the roles of OASIS under pathophysiological conditions, we examined the stress response and inflammatory responses in Oasis deficient (Oasis?/?) mice exposed to dextran sulfate sodium (DSS) to induce colitis. A significant loss of body weight and an increase of mortality were observed in Oasis?/? mice with DSS-induced colitis compared with those in WT mice. The mucosa of the large intestine in Oasis?/? mice exhibited severe damage involving inflammatory cell infiltration. The expression levels of ER stress and apoptosis markers in intestinal epithelial cells were upregulated in Oasis?/? mice. These abnormalities were improved by treatment with tauroursodeoxycholic acid, a chemical chaperone that facilitates protein folding. Taken together, our findings demonstrate that OASIS plays important roles in protection of the large intestinal mucosa in DSS-induced colitis through attenuation of ER stress and inflammation. PMID:24498426

Hino, Kenta; Saito, Atsushi; Asada, Rie; Kanemoto, Soshi; Imaizumi, Kazunori

2014-01-01

182

pH-dependent differential interacting mechanisms of sodium dodecyl sulfate with bovine serum fetuin: a biophysical insight.  

PubMed

Sodium dodecyl sulfate (SDS)-glycoprotein interaction serves as a model for a biological membrane. To get mechanistic insight into the interaction of SDS and glycoprotein, the effect of SDS on bovine serum fetuin (BSF) was studied in subcritical micellar concentrations at pH 7.4 and pH 2 using multiple approaches. SDS interacts electrostatically with BSF through its negatively charged head groups at pH 2 and hydrophobically via its alkyl chains at pH 7.4 up to a 1:20 molar ratio of BSF to SDS. However, at higher concentrations of SDS, BSF undergoes amyloid fibril formation at pH 2, as confirmed by enhanced ThT fluorescence, ?-sheet formation, and TEM microscopy, whereas BSF undergoes induction of an ?-helical structure in the presence of higher SDS concentration at pH 7.4. The increase in ?-helical content with increasing SDS concentrations constrains the environment around tryptophan. As a consequence, the interconversion of tryptophan conformers decreases, resulting in a decrement of the fluorescence lifetime for BSF in the presence of SDS at pH 7.4. PMID:25338219

Zaidi, Nida; Nusrat, Saima; Zaidi, Fatima Kamal; Khan, Rizwan H

2014-11-20

183

Activation of intestinal human pregnane X receptor protects against azoxymethane/dextran sulfate sodium-induced colon cancer.  

PubMed

The role of intestinal human pregnane X receptor (PXR) in colon cancer was determined through investigation of the chemopreventive role of rifaximin, a specific agonist of intestinal human PXR, toward azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced colon cancer. Rifaximin treatment significantly decreased the number of colon tumors induced by AOM/DSS treatment in PXR-humanized mice, but not wild-type or Pxr-null mice. Additionally, rifaximin treatment markedly increased the survival rate of PXR-humanized mice, but not wild-type or Pxr-null mice. These data indicated a human PXR-dependent therapeutic chemoprevention of rifaximin toward AOM/DSS-induced colon cancer. Nuclear factor ?-light-chain-enhancer of activated B cells-mediated inflammatory signaling was upregulated in AOM/DSS-treated mice, and inhibited by rifaximin in PXR-humanized mice. Cell proliferation and apoptosis were also modulated by rifaximin treatment in the AOM/DSS model. In vitro cell-based assays further revealed that rifaximin regulated cell apoptosis and cell cycle in a human PXR-dependent manner. These results suggested that specific activation of intestinal human PXR exhibited a chemopreventive role toward AOM/DSS-induced colon cancer by mediating anti-inflammation, antiproliferation, and proapoptotic events. PMID:25277138

Cheng, Jie; Fang, Zhong-Ze; Nagaoka, Kenjiro; Okamoto, Minoru; Qu, Aijuan; Tanaka, Naoki; Kimura, Shioko; Gonzalez, Frank J

2014-12-01

184

Hexavalent Molybdenum Reduction to Mo-Blue by a Sodium-Dodecyl-Sulfate-Degrading Klebsiella oxytoca Strain DRY14  

PubMed Central

Bacteria with the ability to tolerate, remove, and/or degrade several xenobiotics simultaneously are urgently needed for remediation of polluted sites. A previously isolated bacterium with sodium dodecyl sulfate- (SDS-) degrading capacity was found to be able to reduce molybdenum to the nontoxic molybdenum blue. The optimal pH, carbon source, molybdate concentration, and temperature supporting molybdate reduction were pH 7.0, glucose at 1.5% (w/v), between 25 and 30?mM, and 25°C, respectively. The optimum phosphate concentration for molybdate reduction was 5?mM. The Mo-blue produced exhibits an absorption spectrum with a maximum peak at 865 nm and a shoulder at 700?nm. None of the respiratory inhibitors tested showed any inhibition to the molybdenum-reducing activity suggesting that the electron transport system of this bacterium is not the site of molybdenum reduction. Chromium, cadmium, silver, copper, mercury, and lead caused approximately 77, 65, 77, 89, 80, and 80% inhibition of the molybdenum-reducing activity, respectively. Ferrous and stannous ions markedly increased the activity of molybdenum-reducing activity in this bacterium. The maximum tolerable concentration of SDS as a cocontaminant was 3?g/L. The characteristics of this bacterium make it a suitable candidate for molybdenum bioremediation of sites cocontaminated with detergent pollutant. PMID:24383052

Halmi, M. I. E.; Zuhainis, S. W.; Yusof, M. T.; Shaharuddin, N. A.; Helmi, W.; Shukor, Y.; Syed, M. A.; Ahmad, S. A.

2013-01-01

185

Factors affecting size and swelling of poly(ethylene glycol) microspheres formed in aqueous sodium sulfate solutions without surfactants  

PubMed Central

The LCST behavior of poly(ethylene glycol) (PEG) in aqueous sodium sulfate solutions was exploited to fabricate microspheres without the use of other monomers, polymers, surfactants or organic solvents. Reactive PEG derivatives underwent thermally induced phase separation to produce spherical PEG-rich domains that coarsened in size pending gelation, resulting in stable hydrogel microspheres between ?1–100 microns in size. The time required to reach the gel point during the coarsening process and the extent of crosslinking after gelation both affected the final microsphere size and swelling ratio. The gel point could be varied by pre-reaction of the PEG derivatives below the cloud point, or by controlling pH and temperature above the cloud point. Pre-reaction brought the PEG derivatives closer to the gel point prior to phase separation, while the pH and temperature influenced the rate of reaction. Dynamic light scattering indicated a percolation-to-cluster transition about 3–5 minutes following phase separation. The mean radius of PEG-rich droplets subsequently increased with time to the 1/4th power until gelation. PEG microspheres produced by these methods with controlled sizes and densities may be useful for the production of modular scaffolds for tissue engineering. PMID:19615738

Nichols, Michael D.; Scott, Evan A.; Elbert, Donald L.

2009-01-01

186

Electrosynthesis of polyaniline–mutilwalled carbon nanotube nanocomposite films in the presence of sodium dodecyl sulfate for glucose biosensing  

NASA Astrophysics Data System (ADS)

Polyaniline–mutilwalled carbon nanotube (PANi–MWCNT) nanocomposites were electropolymerized in the presence of sodium dodecyl sulfate (SDS) onto interdigitated platinum-film planar microelectrodes (ID?E). The MWCNTs were first dispersed in SDS solution then mixed with aniline and H2SO4. This mixture was used to electro-synthesize PANi–MWCNT films with potentiostatic method at E = + 0.90 V (versus SCE). The PANi–MWCNT films were characterized by cyclic voltammetry (CV) and scanning electron microscopy (SEM). The results show that the PANi–MWCNT films have a high electroactivity, and a porous and branched structure that can increase the specific surface area for biosensing application. In this work the PANi–MWCNT films were applied for covalent immobilization of glucose oxidase (GOx) via glutaraldehyde agent. The GOx/PANi–MWCNT/ID?E was studied using cyclic voltammetric and chronoamperometric techniques. The effect of several interferences, such as ascorbic acid (AA), uric acid (UA), and acetaminophen (AAP) on the glucosensing at +0.6 V (versus SCE) is not significant. The time required to reach 95% of the maximum steady-state current was less than 5 s. A linear range of the calibration curve for the glucose concentration lies between 1 and 12 mM which is a suitable level in the human body.

Huyen Le, Trong; Thang Trinh, Ngoc; Nguyen, Le Huy; Binh Nguyen, Hai; Nguyen, Van Anh; Tran, Dai Lam; Dung Nguyen, Tuan

2013-06-01

187

Origin of salt additive effect on solute partitioning in aqueous polyethylene glycol-8000-sodium sulfate two-phase system.  

PubMed

Partitioning of a homologous series of dinitrophenylted (DNP-) amino acids with aliphatic side chains was examined in aqueous polyethylene glycol (PEG)-8000-sodium sulfate two-phase systems (ATPS) with the additives NaSCN, NaClO4, and NaH2PO4 at concentrations varied from 0.025M up to 0.54M. The differences between the relative hydrophobicities and electrostatic properties of the two phases in all ATPS were estimated. Partitioning of adenine, adenosine mono-, di- and tri-phosphates was also examined in all ATPSs, including those with NaCl additive. Partition coefficients for these compounds and for nonionic organic compounds previously reported [L.A. Ferreira, P. Parpot, J.A. Teixeira, L.M. Mikheeva, B.Y. Zaslavsky, J. Chromatogr. A 1220 (2012) 14.] were analyzed in terms of linear solvent regression relationship. The results obtained suggest that the effects of the salts additives are related to their influence on the water structure. PMID:24613040

da Silva, Nuno R; Ferreira, Luisa A; Mikheeva, Larissa M; Teixeira, José A; Zaslavsky, Boris Y

2014-04-11

188

Effect of Glu-B3 Allelic Variation on Sodium Dodecyl Sulfate Sedimentation Volume in Common Wheat (Triticum aestivum L.)  

PubMed Central

Sodium dodecyl sulfate (SDS) sedimentation volume has long been used to characterize wheat flours and meals with the aim of predicting processing and end-product qualities. In order to survey the influence of low-molecular-weight glutenin subunits (LMW-GSs) at Glu-B3 locus on wheat SDS sedimentation volume, a total of 283 wheat (Triticum aestivum L.) varieties including landraces and improved and introduced cultivars were analyzed using 10 allele-specific PCR markers at the Glu-B3 locus. The highest allele frequency observed in the tested varieties was Glu-B3i with 21.9% in all varieties, 21.1% in landraces, 25.5% in improved cultivars, and 12% in introduced cultivars. Glu-B3 locus represented 8.6% of the variance in wheat SDS sedimentation volume, and Glu-B3b, Glu-B3g, and Glu-B3h significantly heightened the SDS sedimentation volume, but Glu-B3a, Glu-B3c, and Glu-B3j significantly lowered the SDS sedimentation volume. For the bread-making quality, the most desirable alleles Glu-B3b and Glu-B3g become more and more popular and the least desirable alleles Glu-B3a and Glu-B3c got less and less in modern improved cultivars, suggesting that wheat grain quality in China has been significantly improved through breeding effort. PMID:23861659

Zhao, Manli; He, Fuxia; Ma, Chuanxi

2013-01-01

189

Increased susceptibility to dextran sulfate sodium-induced colitis in the endoplasmic reticulum stress transducer OASIS deficient mice.  

PubMed

OASIS is a basic leucine zipper (bZIP) transmembrane transcription factor that is activated in response to endoplasmic reticulum (ER) stress. Previously, we showed that OASIS regulates final maturation of goblet cells in the large intestine. In the present study, to elucidate the roles of OASIS under pathophysiological conditions, we examined the stress response and inflammatory responses in Oasis deficient (Oasis?/?) mice exposed to dextran sulfate sodium (DSS) to induce colitis. A significant loss of body weight and an increase of mortality were observed in Oasis?/? mice with DSS-induced colitis compared with those in WT mice. The mucosa of the large intestine in Oasis?/? mice exhibited severe damage involving inflammatory cell infiltration. The expression levels of ER stress and apoptosis markers in intestinal epithelial cells were upregulated in Oasis?/? mice. These abnormalities were improved by treatment with tauroursodeoxycholic acid, a chemical chaperone that facilitates protein folding. Taken together, our findings demonstrate that OASIS plays important roles in protection of the large intestinal mucosa in DSS-induced colitis through attenuation of ER stress and inflammation. PMID:24498426

Hino, Kenta; Saito, Atsushi; Asada, Rie; Kanemoto, Soshi; Imaizumi, Kazunori

2014-01-01

190

Interleukin-6, but not the interleukin-6 receptor plays a role in recovery from dextran sodium sulfate-induced colitis  

PubMed Central

Interleukin (IL)-6-deficient, but not IL-6 receptor (IL-6R)-deficient mice present with a delayed skin wound healing phenotype. Since IL-6 solely signals via the IL-6R and glycoprotein 130 (gp130), Il-6r-deficient mice are expected to exhibit a similar phenotype as Il-6-deficient mice. However, p28 (IL-30) and ciliary neurotrophic factor (CNTF) have been identified as additional low-affinity ligands of the IL-6R/gp130/LIFR complex. IL-6 plays an inflammatory and regenerative role in inflammatory bowel disease (IBD). In the present study, we compared Il-6r-deficient mice with mice treated with neutralizing IL-6 monoclonal antibody (mAb) in a model of dextran sodium sulfate (DSS)-induced colitis. Our results, in agreement with those of previous reports, demonstrated that IL-6 mAbs slightly attenuated DSS-induced colitis during the regeneration phase. Il-6r-deficient mice and mice with tissue-specific deletion of the Il-6r in the myeloid cell lineage (LysMCre) with acute and chronic DSS-induced colitis were, however, indistinguishable from wild-type mice. Our data suggest that IL-6 and IL-6R have an additional role in colitis, apart from the IL-6/IL-6R classic and trans-signaling. PMID:24993179

SOMMER, JAN; ENGELOWSKI, ERIKA; BARAN, PAUL; GARBERS, CHRISTOPH; FLOSS, DOREEN M.; SCHELLER, JÜRGEN

2014-01-01

191

Quantification of AAV Particle Titers by Infrared Fluorescence Scanning of Coomassie-Stained Sodium Dodecyl Sulfate–Polyacrylamide Gels  

PubMed Central

Abstract Adeno-associated virus (AAV)-based vectors have gained increasing attention as gene delivery vehicles in basic and preclinical studies as well as in human gene therapy trials. Especially for the latter two—for both safety and therapeutic efficacy reasons—a detailed characterization of all relevant parameters of the vector preparation is essential. Two important parameters that are routinely used to analyze recombinant AAV vectors are (1) the titer of viral particles containing a (recombinant) viral genome and (2) the purity of the vector preparation, most commonly assessed by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) followed by silver staining. An important, third parameter, the titer of total viral particles, that is, the combined titer of both genome-containing and empty viral capsids, is rarely determined. Here, we describe a simple and inexpensive method that allows the simultaneous assessment of both vector purity and the determination of the total viral particle titer. This method, which was validated by comparison with established methods to determine viral particle titers, is based on the fact that Coomassie Brilliant Blue, when bound to proteins, fluoresces in the infrared spectrum. Viral samples are separated by SDS–PAGE followed by Coomassie Brilliant Blue staining and gel analysis with an infrared laser-scanning device. In combination with a protein standard, our method allows the rapid and accurate determination of viral particle titers simultaneously with the assessment of vector purity. PMID:22816378

Kohlbrenner, Erik; Henckaerts, Els; Rapti, Kleopatra; Gordon, Ronald E.; Linden, R. Michael; Hajjar, Roger J.

2012-01-01

192

Oral administration of hen egg white ovotransferrin attenuates the development of colitis induced by dextran sodium sulfate in mice.  

PubMed

Ovotransferrin (OVT), one of the major hen egg white proteins, was shown to possess antimicrobial and antioxidant activities in vitro. However, there is no information regarding the in vivo preventative effect in chronic inflammatory diseases such as inflammatory bowel disease (IBD). The aim of the present study is to evaluate the anti-inflammatory effects of OVT in a mouse model of dextran sodium sulfate (DSS)-induced colitis. OVT (50 or 250 mg/kg BW) was given orally for 14 days to female BALB/c mice, and 5% DSS (MW 36-50 kDa) was used to induce acute colitis (days 7-14) via drinking water. The current in vivo study demonstrated that OVT significantly reduced clinical signs, weight loss, shortening of the colon, and inflammatory cytokine markers of disease. The histopathological analysis of the colon revealed that OVT reduced histological scores. These results indicate that the use of OVT may be a potential promising candidate for the prevention of IBD. PMID:25602920

Kobayashi, Yutaro; Rupa, Prithy; Kovacs-Nolan, Jennifer; Turner, Patricia V; Matsui, Toshiro; Mine, Yoshinori

2015-02-11

193

Inactivation of salmonella in biofilms and on chicken cages and preharvest poultry by levulinic Acid and sodium dodecyl sulfate.  

PubMed

Surface contamination (skin and feathers) of broilers with Salmonella occurs primarily during growth and transportation. Immediately after transporting chickens, chicken cage doors were sprayed with a foam containing 3% levulinic acid plus 2% sodium dodecyl sulfate (SDS). Samples were collected for Salmonella assay after 45 min. Salmonella on cage doors was reduced from 19% (19 of 100 doors) before treatment to 1% (1 of 100 doors) after treatment, coliform counts were reduced from 6 to 8 to 2 to 4 log CFU/9 cm(2), and aerobic plate counts were reduced from 7 to 9 to 4 to 6 log CFU/9 cm(2). Whole chicken carcasses with feathers were inoculated with 10(8) CFU of Salmonella Enteritidis, soaked for 5 min at 21°C in 72 liters of a treatment or control solution, and assayed for Salmonella. Salmonella counts on chickens treated with water were 6.8 to 8.5 log CFU/9 cm(2), those treated with 50 ppm of calcium hypochlorite were 7.6 to 8.9 log CFU/9 cm(2), and those treated with 3% levulinic acid plus 2% SDS were <1.7 to 2.8 CFU/9 cm(2) (>4-log reduction). Results of biofilm studies on surfaces of various materials revealed that a 3% levulinic acid plus 2% SDS treatment used as either a foam or liquid for 10 min effectively reduced Salmonella populations by 5 and >6 log CFU/cm(2), respectively. PMID:22186041

Zhao, Tong; Zhao, Ping; Cannon, Jennifer L; Doyle, Michael P

2011-12-01

194

Asiatic acid ameliorates dextran sulfate sodium-induced murine experimental colitis via suppressing mitochondria-mediated NLRP3 inflammasome activation.  

PubMed

In the present study, the effect of asiatic acid, a natural triterpenoid compound, on murine experimental colitis induced by dextran sulfate sodium (DSS) and its possible mechanism were examined in vivo and vitro. Oral administration of asiatic acid dose-dependently attenuated the loss of body weight and shortening of colon length induced by DSS. The disease activity index, histopathologic scores of musco and myeloperoxidase activity were also significantly reduced by asiatic acid treatment. Protein and mRNA levels of DSS-induced pro-inflammatory cytokines in colon, including TNF-?, IL-1?, IL-6 and IFN-?, were markedly suppressed by asiatic acid. At the same time, decreased activation of caspase-1 in peritoneal macrophages was detected in asiatic acid-treated mice, which suggested that the NLRP3 inflammasome activation was suppressed. In addition, we also found that asiatic acid dose-dependently inhibited IL-1? secretion, caspase-1 activation as well as inflammasome assembling in vitro. Furthermore, the mechanism of asiatic acid was related to the inhibition of mitochondrial reactive oxygen species generation and prevention of mitochondrial membrane potential collapse. Taken together, our results demonstrate the ability of asiatic acid to inhibit NLRP3 inflammasome activation and its potential usage in the treatment of inflammatory bowel diseases. PMID:25523461

Guo, Wenjie; Liu, Wen; Jin, Biao; Geng, Ji; Li, Jing; Ding, Hongqun; Wu, Xuefeng; Xu, Qiang; Sun, Yang; Gao, Jing

2015-02-01

195

Molecular dynamics simulation of cetyltrimethylammonium bromide and sodium octyl sulfate mixtures: aggregate shape and local surfactant distribution.  

PubMed

To examine the self-assembly of cationic-anionic (catanionic) surfactant mixtures, we performed molecular dynamical (MD) simulations at fixed surfactant numbers but different ratios of cationic cetyltrimethylammonium bromide (CTAB) and anionic sodium octyl sulfate (SOS) aqueous mixtures, which were investigated previously (J. Phys. Chem. 1996, 100, 5874-5879). The simulation results show that with an increase of CTAB, there are two different potential aggregation evolving paths. For SOS-rich mixtures, the aggregation transition is sphere-disc-rod, while in CTAB-rich mixtures, it is rod-sphere. Furthermore, a disc micelle model was built to explain the shape of the aggregates with varying compositions of CTAB and SOS. In the model, the surfactant distribution in disc micelles is spontaneously adjusted according to the different curvature of the disc surface. The short-tailed SOS tends to stay in the edge region of high curvature, while in the disc center, where the curvature is very low, equimolar mixing of cationic and anionic surfactants is better for the arrangement of CTAB and SOS. Based on this model, the relation between the shape and composition of CTAB and SOS aggregates is well established by analyzing the local surfactant distribution. These new simulations on the evolving mechanism of aggregate shape are very important for the full understanding of the complex phase behavior in cationic and anionic mixtures and for the self-assembly of other mixed surfactant systems. PMID:23463240

Chen, Jingfei; Hao, Jingcheng

2013-04-21

196

Detection of N-glycans on small amounts of glycoproteins in tissue samples and sodium dodecyl sulfate-polyacrylamide gels.  

PubMed

N-linked glycans harbored on glycoproteins profoundly affect the character of proteins by altering their structure or capacity to bind to other molecules. Specific knowledge of the role of N-glycans in these changes is limited due to difficulties in identifying precise carbohydrate structures on a given glycoprotein, which arises from the large amounts of glycoprotein required for N-glycan structural determination. Here, we refined a simple method to purify and detect trace amounts of N-glycans. During the N-glycan purification step, most contaminants were removed by two kinds of columns: a graphite carbon column and a cellulose column. N-Glycans were identified with a three-dimensional high-performance liquid chromatography (HPLC) system. Using our method, a global analysis of N-glycans from human muscle biopsy samples and mouse brain sections was possible. By combining sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) with our method, we refined analytical procedures for N-glycans from SDS-PAGE gels using hydrazinolysis to achieve a high N-glycan recovery rate. N-Glycans on as little as 1 ?g of the target protein transferrin or immunoglobulin G (IgG) were easily detected. These methods allowed us to efficiently determine glycoprotein N-glycans at picomole (pmol) levels. PMID:22369894

Yoshimura, Takeshi; Yamada, Gen; Narumi, Mai; Koike, Takako; Ishii, Akihiro; Sela, Ilan; Mitrani-Rosenbaum, Stella; Ikenaka, Kazuhiro

2012-04-15

197

Small angle neutron scattering study of sodium dodecyl sulfate micellar growth driven by addition of a hydrotropic salt.  

PubMed

The structures of aggregates formed in aqueous solutions of an anionic surfactant, sodium dodecyl sulfate (SDS), with the addition of a cationic hydrotropic salt, p-toluidine hydrochloride (PTHC), have been investigated by small angle neutron scattering (SANS). The SANS spectra exhibit a pronounced peak at low salt concentration, indicating the presence of repulsive intermicellar interactions. Model-independent real space information about the structure is obtained from a generalized indirect Fourier transformation (GIFT) technique in combination with a suitable model for the interparticle structure factor. The interparticle interaction is captured using the rescaled mean spherical approximation (RMSA) closure relation and a Yukawa form of the interaction potential. Further quantification of the geometrical parameters of the micelles was achieved by a complete fit of the SANS data using a prolate ellipsoidal form factor and the RMSA structure factor. The present study shows that PTHC induces a decrease in the fractional charge of the micelles due to adsorption at the micellar surface and consequent growth of the SDS micelles from nearly globular to rodlike as the concentration of PTHC increases. PMID:16256467

Hassan, P A; Fritz, Gerhard; Kaler, Eric W

2003-01-01

198

Caspase-11 is expressed in the colonic mucosa and protects against dextran sodium sulfate-induced colitis.  

PubMed

Ulcerative colitis and Crohn's disease are major inflammatory syndromes that affect millions of patients. Caspase-11 confers protection against Gram-negative enteropathogens, but its role during colitis is unknown. Here, we show that caspase-11 was constitutively expressed in the colon, and that caspase-11-deficient (caspase-11(-/-)) mice were hypersusceptible to dextran sodium sulfate (DSS)-induced colitis. Notably, pro-inflammatory Prevotella species were strongly reduced in the gut microbiota of caspase-11(-/-) mice. Co-housing with wild-type mice leveled Prevotella contents, but failed to protect caspase-11(-/-) mice from increased susceptibility to DSS-induced colitis. We therefore addressed the role of caspase-11 in immune signaling. DSS-induced tissue damage, release of the pyroptosis/necroptosis marker HMGB1, and inflammatory cell infiltration in the gut were markedly increased in caspase-11(-/-) mice. Moreover, caspase-11(-/-) mice showed normal or increased production of mature interleukin (IL)-1? and IL-18, whereas IL-1? and IL-18 secretion was blunted in animals lacking both caspases 1 and 11. In conclusion, we showed that caspase-11 shapes the gut microbiota composition, and that caspase-11(-/-) mice are highly susceptible to DSS-induced colitis. Moreover, DSS-induced inflammasome activation relied on caspase-1, but not caspase-11. These results suggest a role for other caspase-11 effector mechanisms such as pyroptosis in protection against intestinal inflammation. PMID:24850431

Demon, D; Kuchmiy, A; Fossoul, A; Zhu, Q; Kanneganti, T-D; Lamkanfi, M

2014-11-01

199

Crystallization and aggregation behaviors of calcium carbonate in the presence of poly(vinylpyrrolidone) and sodium dodecyl sulfate.  

PubMed

An anionic surfactant interacts strongly with a polymer molecule to form a self-assembled structure, due to the attractive force of the hydrophobic association and electrostatic repulsion. In this crystallization medium, the surfactant-stabilized inorganic particles adsorbed on the polymer chains, as well as the bridging effect of polymer molecules, controlled the aggregation behavior of colloidal particles. In this presentation, the spontaneous precipitation of calcium carbonate (CaCO3) was conducted from the aqueous systems containing a water-soluble polymer (poly(vinylpyrrolidone), PVP) and an anionic surfactant (sodium dodecyl sulfate, SDS). When the SDS concentrations were lower than the onset of interaction between PVP and SDS, the precipitated CaCO3 crystals were typically hexahedron-shaped calcite; the increasing SDS concentration caused the morphologies of CaCO3 aggregates to change from the flower-shaped calcite to hollow spherical calcite, then to solid spherical vaterite. These results indicate that the self-organized configurations of the polymer/surfactant supramolecules dominate the morphologies of CaCO3 aggregates, implying that this simple and versatile method expands the morphological investigation of the mineralization process. PMID:16853360

Shen, Qiang; Wei, Hao; Wang, Liancheng; Zhou, Yong; Zhao, Ying; Zhang, Zhiqing; Wang, Dujin; Xu, Guiying; Xu, Duanfu

2005-10-01

200

Efficacy of a combination of FCHG49™ glucosamine hydrochloride, TRH122™ low molecular weight sodium chondroitin sulfate and manganese ascorbate* in the management of knee osteoarthritis  

Microsoft Academic Search

Objectives The objective of this study was to evaluate the oral combination of glucosamine HCl, sodium chondroitin sulfate and manganese ascorbate for the treatment of osteoarthritis (OA) of the knee.Design A randomized placebo-controlled study design was implemented. We recruited 93 patients with OA of the knee from a single center. The intervention group received 1000mg FCHG49™ glucosamine HCl, 800mg TRH122™

A. Das; T. A. Hammad

2000-01-01

201

Subchronic (26- and 52-week) toxicity and irritation studies of a novel microbicidal gel formulation containing sodium lauryl sulfate in animal models.  

PubMed

The safety of an ethylene oxide/propylene oxide gel formulation containing sodium lauryl sulfate (2%, w/w), that could be a potent candidate as a topical microbicide, has been evaluated. More specifically, the subchronic (26- and 52-week) toxicity of the formulation when applied intravaginally as well as its irritating potential for the rectal, penile, eye, skin and buccal mucosa have been examined in animal models. The results showed that the vaginal administration of the gel formulation containing sodium lauryl sulfate once and twice daily (with doses 12 +/- 2 h apart) for 26 weeks to rats and for 52 weeks to rabbits induced slight to moderate histopathological alterations. When the formulation was applied intrarectally to male and female rabbits once and twice daily (with doses 12 +/- 2 h apart) for 14 days, no macroscopic or microscopic changes were reported. For both vaginal and rectal dosing, no effect was seen on the haematology, coagulation and serum chemistry parameters as well as on the body weight of animals and the relative organ weights. Other sporadic macroscopic and histopathological findings were incidental in origin and of no toxicological significance. The gel formulation containing sodium lauryl sulfate was considered as mildly irritating for the penile mucosa of rabbits, non-irritating for the eye of rabbits, mildly irritating for the skin in a rabbit model and non-irritating for the hamster cheek pouch. It is suggested that the gel formulation containing sodium lauryl sulfate is safe for most tissues that could be exposed to the product under normal use. PMID:17549701

Piret, Jocelyne; Laforest, Geneviève; Bussières, Martin; Bergeron, Michel G

2008-03-01

202

Changes in tyrosinase specificity by ionic liquids and sodium dodecyl sulfate.  

PubMed

Tyrosinase is a member of the type 3 copper enzyme family involved in the production of melanin in a wide range of organisms. The ability of tyrosinases to convert monophenols into diphenols has stimulated studies regarding the production of substituted catechols, important intermediates for the synthesis of pharmaceuticals, agrochemicals, polymerization inhibitors, and antioxidants. Despite its enormous potential, the use of tyrosinases for catechol synthesis has been limited due to the low monophenolase/diphenolase activity ratio. In the presence of two water miscible ionic liquids, [BMIM][BF(4)] and ethylammonium nitrate, the selectivity of a tyrosinase from Bacillus megaterium (TyrBm) was altered, and the ratio of monophenolase/diphenolase activity increased by up to 5-fold. Furthermore, the addition of sodium dodecyl sulphate (SDS) at levels of 2-50 mM increased the activity of TyrBm by 2-fold towards the natural substrates L-tyrosine and L-Dopa and 15- to 20-fold towards the non-native phenol and catechol. The R209H tyrosinase variant we previously identified as having a preferential ratio of monophenolase/diphenolase activity was shown to have a 45-fold increase in activity towards phenol in the presence of SDS. We propose that the effect of SDS on the ability of tyrosinase to convert non-natural substrates is due to the interaction of surfactant molecules with residues located at the entrance to the active site, as visualized by the newly determined crystal structure of TyrBm in the presence of SDS. The effect of SDS on R209 may enable less polar substrates such as phenol and catechol, to penetrate more efficiently into the enzyme catalytic pocket. PMID:22539021

Goldfeder, Mor; Egozy, Mor; Shuster Ben-Yosef, Vered; Adir, Noam; Fishman, Ayelet

2013-03-01

203

Extracellular Vesicles Derived from Gut Microbiota, Especially Akkermansia muciniphila, Protect the Progression of Dextran Sulfate Sodium-Induced Colitis  

PubMed Central

Gut microbiota play an important part in the pathogenesis of mucosal inflammation, such as inflammatory bowel disease (IBD). However, owing to the complexity of the gut microbiota, our understanding of the roles of commensal and pathogenic bacteria in the maintenance of immune homeostasis in the gut is evolving only slowly. Here, we evaluated the role of gut microbiota and their secreting extracellular vesicles (EV) in the development of mucosal inflammation in the gut. Experimental IBD model was established by oral application of dextran sulfate sodium (DSS) to C57BL/6 mice. The composition of gut microbiota and bacteria-derived EV in stools was evaluated by metagenome sequencing using bacterial common primer of 16S rDNA. Metagenomics in the IBD mouse model showed that the change in stool EV composition was more drastic, compared to the change of bacterial composition. Oral DSS application decreased the composition of EV from Akkermansia muciniphila and Bacteroides acidifaciens in stools, whereas increased EV from TM7 phylum, especially from species DQ777900_s and AJ400239_s. In vitro pretreatment of A. muciniphila-derived EV ameliorated the production of a pro-inflammatory cytokine IL-6 from colon epithelial cells induced by Escherichia coli EV. Additionally, oral application of A. muciniphila EV also protected DSS-induced IBD phenotypes, such as body weight loss, colon length, and inflammatory cell infiltration of colon wall. Our data provides insight into the role of gut microbiota-derived EV in regulation of intestinal immunity and homeostasis, and A. muciniphila-derived EV have protective effects in the development of DSS-induced colitis. PMID:24204633

Kang, Chil-sung; Ban, Mingi; Choi, Eun-Jeong; Moon, Hyung-Geun; Jeon, Jun-Sung; Kim, Dae-Kyum; Park, Soo-Kyung; Jeon, Seong Gyu; Roh, Tae-Young; Myung, Seung-Jae

2013-01-01

204

Systemic responses of mice to dextran sulfate sodium-induced acute ulcerative colitis using 1H NMR spectroscopy.  

PubMed

The interplay between genetic mutation and environmental factors is believed to contribute to the etiology of inflammatory bowel disease (IBD). While focused attention has been paid to the aforementioned research, time-specific and organ-specific metabolic changes associated with IBD are still lacking. Here, we induced acute ulcerative colitis in mice by providing water containing 3% dextran sulfate sodium (DSS) for 7 days and investigated the metabolic changes of plasma, urine, and a range of biological tissues by employing a (1)H nuclear magnetic resonance (NMR)-based metabonomics approach with complementary information on serum clinical chemistry and histopathology. We found that DSS-induced acute ulcerative colitis leads to significant elevations in the levels of amino acids in plasma and decreased levels in the membrane-related metabolites and a range of nucleotides, nucleobases, and nucleosides in the colon. In addition, acute-colitis-induced elevations in the levels of nucleotides in the liver were observed, accompanied by reduced levels of glucose. DSS-induced acute colitis also resulted in increased levels of oxidized glutathione and attenuated levels of taurine in the spleen. Furthermore, acute colitis resulted in depletion in the levels of gut microbial cometabolites in urine along with an increase in citric acid cycle intermediates. These findings suggest that DSS-induced acute colitis causes a disturbance of lipid and energy metabolism, damage to the colon and liver, a promoted antioxidative and anti-inflammatory response, and perturbed gut microbiotal communities. The information obtained here provided details of the time-dependent and holistic metabolic changes in the development of the DSS-induced acute ulcerative colitis, which could be useful in discovery of novel therapeutic targets for management of IBD. PMID:23651354

Dong, Fangcong; Zhang, Lulu; Hao, Fuhua; Tang, Huiru; Wang, Yulan

2013-06-01

205

Suppressive effects of Moringa oleifera Lam pod against mouse colon carcinogenesis induced by azoxymethane and dextran sodium sulfate.  

PubMed

Moringa oleifera Lam (horseradish tree; tender pod or fruits) is a major ingredient in Thai cuisine and has some medicinal properties. Previous studies have shown potentially antioxidant, antitumor promoter, anticlastogen and anticarcinogen activities both in vitro and in vivo. The present study was conducted to investigate chemopreventive effects on azoxymethane (AOM)-initiated and dextran sodium sulfate (DSS)-promoted colon carcinogenesis in mice. Male ICR mice were divided into 8 groups: Group 1 served as a negative control; Group 2 received AOM/DSS as a positive control; Groups 3-5 were fed boiled freeze-dried M. oleifera (bMO) at 1.5%, 3.0% and 6.0%, respectively supplemented in basal diets for 5 weeks; Groups 6-8 were fed with bMO diets at the designed doses above for 2 weeks prior to AOM, during and 1 week after DSS administration. At the end of the study, colon samples were processed for histopathological examination. PCNA indices, and iNOS and COX-2 expression were assessed by immunohistochemistry. The results demonstrated the incidences and multiplicities of tumors in Groups 6-8 to be decreased when compared to Group 2 in a dose dependent manner, but this was significant only in Group 8. The PCNA index was also significantly decreased in Group 8 whereas iNOS and COX-2 protein expression were significantly decreased in Groups 7 and 8. The findings suggest that M. oleifera Lam pod exerts suppressive effects in a colitis-related colon carcinogenesis model induced by AOM/DSS and could serve as a chemopreventive agent. PMID:22471457

Budda, Sirintip; Butryee, Chaniphun; Tuntipopipat, Siriporn; Rungsipipat, Anudep; Wangnaithum, Supradit; Lee, Jeong-Sang; Kupradinun, Piengchai

2011-01-01

206

Vitamin D Regulates the Gut Microbiome and Protects Mice from Dextran Sodium Sulfate–Induced Colitis123  

PubMed Central

The active form of vitamin D [1,25-dihydroxycholecalciferol, 1,25(OH)2D3] and the vitamin D receptor (VDR) regulate susceptibility to experimental colitis. The effect of the bacterial microflora on the susceptibility of C57BL/6 mice to dextran sodium sulfate–induced colitis was determined. Mice that cannot produce 1,25(OH)2D3 [Cyp27b1 (Cyp) knockout (KO)], VDR KO as well as their wild-type littermates were used. Cyp KO and VDR KO mice had more bacteria from the Bacteroidetes and Proteobacteria phyla and fewer bacteria from the Firmicutes and Deferribacteres phyla in the feces compared with wild-type. In particular, there were more beneficial bacteria, including the Lactobacillaceae and Lachnospiraceae families, in feces from Cyp KO and VDR KO mice than in feces from wild-type. Helicobacteraceae family member numbers were elevated in Cyp KO compared with wild-type mice. Depletion of the gut bacterial flora using antibiotics protected mice from colitis. 1,25(OH)2D3 treatment (1.25 ?g/100 g diet) of Cyp KO mice decreased colitis severity and reduced the numbers of Helicobacteraceae in the feces compared with the numbers in the feces of untreated Cyp KO mice. The mechanisms by which the dysbiosis occurs in VDR KO and Cyp KO mice included lower expression of E-cadherin on gut epithelial and immune cells and fewer tolerogenic dendritic cells that resulted in more gut inflammation in VDR and Cyp KO mice compared with wild-type mice. Increased host inflammation has been shown to provide pathogens with substrates to out-compete more beneficial bacterial species. Our data demonstrate that vitamin D regulates the gut microbiome and that 1,25(OH)2D3 or VDR deficiency results in dysbiosis, leading to greater susceptibility to injury in the gut. PMID:23966330

Ooi, Jot Hui; Li, Yunfei; Rogers, Connie J.; Cantorna, Margherita T.

2013-01-01

207

Extracellular vesicles derived from gut microbiota, especially Akkermansia muciniphila, protect the progression of dextran sulfate sodium-induced colitis.  

PubMed

Gut microbiota play an important part in the pathogenesis of mucosal inflammation, such as inflammatory bowel disease (IBD). However, owing to the complexity of the gut microbiota, our understanding of the roles of commensal and pathogenic bacteria in the maintenance of immune homeostasis in the gut is evolving only slowly. Here, we evaluated the role of gut microbiota and their secreting extracellular vesicles (EV) in the development of mucosal inflammation in the gut. Experimental IBD model was established by oral application of dextran sulfate sodium (DSS) to C57BL/6 mice. The composition of gut microbiota and bacteria-derived EV in stools was evaluated by metagenome sequencing using bacterial common primer of 16S rDNA. Metagenomics in the IBD mouse model showed that the change in stool EV composition was more drastic, compared to the change of bacterial composition. Oral DSS application decreased the composition of EV from Akkermansia muciniphila and Bacteroides acidifaciens in stools, whereas increased EV from TM7 phylum, especially from species DQ777900_s and AJ400239_s. In vitro pretreatment of A. muciniphila-derived EV ameliorated the production of a pro-inflammatory cytokine IL-6 from colon epithelial cells induced by Escherichia coli EV. Additionally, oral application of A. muciniphila EV also protected DSS-induced IBD phenotypes, such as body weight loss, colon length, and inflammatory cell infiltration of colon wall. Our data provides insight into the role of gut microbiota-derived EV in regulation of intestinal immunity and homeostasis, and A. muciniphila-derived EV have protective effects in the development of DSS-induced colitis. PMID:24204633

Kang, Chil-Sung; Ban, Mingi; Choi, Eun-Jeong; Moon, Hyung-Geun; Jeon, Jun-Sung; Kim, Dae-Kyum; Park, Soo-Kyung; Jeon, Seong Gyu; Roh, Tae-Young; Myung, Seung-Jae; Gho, Yong Song; Kim, Jae Gyu; Kim, Yoon-Keun

2013-01-01

208

Evaluation of levulinic acid and sodium dodecyl sulfate as a sanitizer for use in processing Georgia-grown cantaloupes.  

PubMed

Freshly harvested Georgia-grown cantaloupes (Cucumis melo L. var. reticulatus cv. Athena and Atlantis) were spot inoculated with 100 ?l of a five-strain mixture of Salmonella enterica serovar Poona (9 log CFU/ml) at the stem scar and on the netted rind and then subjected to no treatment (control) or a 6-min treatment (tank only) in water, 120 ppm of chlorine (pH 7.0), 1% levulinic acid plus 0.1% sodium dodecyl sulfate (SDS; pH 3.0), or 2% levulinic acid plus 0.2% SDS (pH 3.0). The log reduction for the tank-only treatments was 0.31, 0.59, 1.32, and 1.37 log CFU/g at the stem scar and 0.97, 1.59, 2.06. and 3.37 log CFU/g on the netted rind for water, chlorine, 1% levulinic acid plus 0.1% SDS, and 2% levulinic acid plus 0.2% SDS, respectively. A greater log reduction was observed for the cantaloupe surface tissue with the water, chlorine, and 2% levulinic acid plus 0.2% SDS treatments when additional sanitizer (2 ml) and brushing (to simulate cantaloupes tumbling over brushes on the processing line) were added to the dump tank treatment. The stem scar tissue reductions were 0.90, 1.69, and 1.53 log CFU/g, whereas the netted rind reductions were 1.56, 2.50, and 4.47 log CFU/g after treatment with water, chlorine, and 2% levulinic acid plus 0.2% SDS, respectively. These data suggest that 2% levulinic acid plus 0.2% SDS is effective for reducing Salmonella on the netted rind surface of cantaloupes. However, neither 2% levulinic acid plus 0.2% SDS nor 120 ppm of chlorine substantially reduced Salmonella on stem scar tissue. PMID:24112578

Webb, Cathy C; Davey, Lindsey E; Erickson, Marilyn C; Doyle, Michael P

2013-10-01

209

Clcn5 knockout mice exhibit novel immunomodulatory effects and are more susceptible to dextran sulfate sodium-induced colitis.  

PubMed

Although the intracellular Cl(-)/H(+) exchanger Clc-5 is expressed in apical intestinal endocytic compartments, its pathophysiological role in the gastrointestinal tract is unknown. In light of recent findings that CLC-5 is downregulated in active ulcerative colitis (UC), we tested the hypothesis that loss of CLC-5 modulates the immune response, thereby inducing susceptibility to UC. Acute dextran sulfate sodium (DSS) colitis was induced in Clcn5 knockout (KO) and wild-type (WT) mice. Colitis, monitored by disease activity index, histological activity index, and myeloperoxidase activity were significantly elevated in DSS-induced Clcn5 KO mice compared with those in WT mice. Comprehensive serum multiplex cytokine profiling demonstrated a heightened Th1-Th17 profile (increased TNF-alpha, IL-6, and IL-17) in DSS-induced Clcn5 KO mice compared with that in WT DSS colitis mice. Interestingly, Clcn5 KO mice maintained on a high vitamin D diet attenuated DSS-induced colitis. Immunofluorescence and Western blot analyses of colonic mucosa validated the systemic cytokine patterns and further revealed enhanced activation of the NF-kappaB pathway in DSS-induced Clcn5 KO mice compared with those in WT mice. Intriguingly, high baseline levels of IL-6 and phospho-IkappaB were observed in Clcn5 KO mice, suggesting a novel immunopathogenic role for the functional defects that result from the loss of Clc-5. Our studies demonstrate that the loss of Clc-5 1) exhibits IL-6-mediated immunopathogenesis, 2) significantly exacerbated DSS-induced colitis, which is influenced by dietary factors, including vitamin D, and 3) portrays distinct NF-kappaB-modulated Th1-Th17 immune dysregulation, implying a role for CLC-5 in the immunopathogenesis of UC. PMID:20181886

Alex, Philip; Ye, Mei; Zachos, Nicholas C; Sipes, Jennifer; Nguyen, Thuan; Suhodrev, Maxim; Gonzales, Liberty; Arora, Zubin; Zhang, Ting; Centola, Michael; Guggino, Sandra E; Li, Xuhang

2010-04-01

210

Alanyl-glutamine administration suppresses Th17 and reduces inflammatory reaction in dextran sulfate sodium-induced acute colitis.  

PubMed

T helper (Th) cells play a major role in the pathogenesis of inflammatory bowel disease (IBD). Glutamine (Gln) is known to have immunomodulatory effects in metabolic stressed conditions. This study investigated the effects of post-treatment of alanyl-glutamine (Ala-Gln) on Th cell-associated cytokine expressions and inflammatory reaction in dextran sulfate sodium (DSS)-induced colitis. C57BL/6 mice received distilled water containing 3% DSS for 5 days to induce colitis, whereas the normal control (NC) group received distilled water. After induction of colitis, one of the colitis groups (DG) was intraperitoneally injected with an Ala-Gln solution (0.5 g Gln/kg/d), and the saline DSS group (DS) received an identical volume of saline. After treatment for 3 days, mice were sacrificed, and the blood and tissue samples were collected for further analysis. DSS colitis resulted in higher percentages of blood interleukin (IL)-17-secreting Th cells and greater expression of Th cell-associated cytokine messenger RNA (mRNA) in the mesenteric lymph nodes (MLN). Also, luminal immunoglobin (Ig) G, keratinocyte-derived chemokine, and macrophage chemoattractant protein-1 levels were higher in the DS group than the NC group, whereas these parameters did not differ between the DG and NC groups. The DG group had lower blood IL-17A, 17F, MLN IL-17 mRNA and macrophage percentage in the peritoneal lavage fluid than those of the DS group. These results suggest that post-treatment with Ala-Gln suppressed Th17-associated cytokine expressions, reduced macrophage infiltration into the peritoneal cavity and decreased pro-inflammatory cytokine production in the colon, thus may have attenuated inflammatory response in DSS-induced colitis. PMID:23721689

Hou, Yu-Chen; Liu, Jun-Jen; Pai, Man-Hui; Tsou, Shung-Sheng; Yeh, Sung-Ling

2013-09-01

211

Simulation of blood oxygenation in capillary membrane oxygenators using modified sulfite solution.  

PubMed

Blood oxygenation is the main performance characteristic of capillary membrane oxygenators (CMOs). Handling of natural blood in in vitro investigations of CMOs is quite complex and time-consuming. Since the conventional blood analog fluids (e.g. water/glycerol) lack a substance with an affinity to capture oxygen comparable to hemoglobin's affinity, in this study a novel approach using modified sulfite solution is proposed to address this challenge. The solution comprises sodium sulfite as a component, simulating the role of hemoglobin in blood oxygenation. This approach is validated by OTR (oxygen transfer rate) measured using native porcine blood, in two types of commercially available CMOs. Consequently, the number of complicated natural blood investigations in the evolution procedure of newly developed oxygenators would considerably decrease. Moreover, the reassessing of failed devices, in clinics, would be performed more precisely using a modified sulfite solution than simple water/glycerol testing. PMID:25159916

Tabesh, Hadi; Amoabediny, Ghasem; Rasouli, Ali; Ramedani, Arash; Poorkhalil, Ali; Kashefi, Ali; Mottaghy, Khosrow

2014-12-01

212

Interactions between hydrophobically modified alkali-swellable emulsion polymers and sodium dodecyl sulfate probed by fluorescence and rheology.  

PubMed

The interactions between a pyrene-labeled hydrophobically modified alkali-swellable emulsion (Py-HASE) polymer and the anionic surfactant sodium dodecyl sulfate (SDS) in aqueous solution were investigated with a fluorometer, a rheometer, and a combination of both instruments to probe the fluorescence of the polymer while the solution was being sheared. Different amounts of SDS were added to two solutions with Py-HASE concentrations of 8 and 57 g/L. The pyrene monomer and excimer decays of the Py-HASE solutions were acquired and globally fitted according to the fluorescence blob model (FBM) and the model free (MF) analysis. Both models yielded the same molar fractions of pyrenes that were isolated, aggregated, or forming excimer by diffusion. The average number of pyrenes per micelle, , was determined according to the FBM and found to equal 2.0 at the SDS concentration corresponding to a maximum in solution viscosity. For a Py-HASE concentration of 57 g/L, the solution viscosities at different SDS concentrations were measured from the Newtonian plateau regions and were found to peak at an SDS concentration of 11 mM. The steady-state fluorescence spectra were acquired at SDS concentrations of 0.1, 6.0, 11.1, and 17 mM while the 57 g/L Py-HASE solution was sheared. Although the solutions of Py-HASE and SDS were found to shear-thin substantially with the solution viscosity decreasing by up to 4 orders of magnitude, no change was observed in the fluorescence spectra acquired at shear rates ranging from 0.005 to 500 s(-1). The overlap of the fluorescence spectra under conditions where the solution viscosity decreased by 4 orders of magnitude suggested that the rearrangement of the hydrophobes from inter- to intramolecular associations that leads to shear-thinning occurs on a time scale that is much faster than that over which the rheology experiments are being conducted. PMID:24364758

Chen, Shaohua; Siu, Howard; Duhamel, Jean

2014-01-01

213

Effects of multi-walled carbon nanotubes on mineralization and mobility of nonylphenol and sodium dodecyl sulfate in agricultural soils  

NASA Astrophysics Data System (ADS)

Nanotechnology is one of the major scientific research fields in this decade. One of the most wide-spread nanomaterials are carbon based nanoparticles (CNPs) which are increasingly be used in industry. Several studies shows that CNPs are interacting with other chemical compounds and organic pollutants in the environment. It is assumed that the interactions between CNPs and organic pollutants are affected by solution and aggregate behavior. Based on the knowledge of the behavior of CNPs and organic pollutants in aquatic systems the interactions of CNPs and organic pollutants in agricultural soils have to be studied. As organic pollutants two environmental substances, nonylphenol (NP) and sodium dodecyl sulfate (SDS) were selected as model substances. They occur frequently in aqueous systems and also show different solubility behavior. As CNP representatives, two different multi-walled carbon nanotubes (MWNT) were selected. They differed either in length or outer diameter. Conclusions therefrom are to be closed the influence of length and diameter of the sorption capacity of different organic pollutants. In addition, two agricultural soils (sandy and silty soil) and one forest soil (sandy soil) were chosen. Mineralization and sorption experiments were conducted to provide information about the degradation of organic pollutants in presence of multi-walled carbon nanotubes in soils. To analyze the CNPs mineralization potential, peroxidase activity was measured. Further extraction experiments were conducted to detect the extractable part of organic pollutants. The results show that the surface area of the MWNT has a significant impact on the sorption behav-ior of NP and SDS in soils. The sorption of NP and SDS is much higher than without MWNT. However, the properties of the organic pollutants (different water solubility and hydrophobicity) are equally important and should be noted. The degradation of both pollutants is influenced by MWNT. Due to the strong sorption of NP and SDS on the MWNT, the degradation of these pollutants in soils, is slower than without MWNT. The peroxidase activity did not contribute to NP and SDS degradation. But the peroxidase activity in agricultural soils is higher than in forest soils. The extractable fraction of NP and SDS is very low and amounts to a maximum of 2 %. Due to the lower degradation of NP and SDS in the presence of MWNT a longer retention of the substances in the soils and potential toxic effects for humans and animals, as a result of plant uptake may be taken into account.

Lillotte, Julia; Marschner, Bernd; Stumpe, Britta

2014-05-01

214

The small intestinal apical hydrolase activities are decreased in the piglet with bowel inflammation induced by dextran sodium sulfate.  

PubMed

Inflammatory bowel disease (IBD) is characterized by cramping, abdominal pain, bloating, constipation, and diarrhea. We tested the hypothesis that compromised activities of the major small intestinal apical hydrolases contribute to the symptoms of IBD. Changes in hydrolytic kinetics, target protein abundances, and mRNA expression of intestinal alkaline phosphatase (IAP), lactase, maltase, sucrase-isomaltase (SI), maltase-glucoamylase (MGA), and aminopeptidase N (APN) in piglets with colonic inflammation chemically induced by dextran sodium sulfate (DSS) were investigated. Yorkshire piglets at 5 d of age, with an average initial BW of about 3 kg, were fitted with intragastric catheters and were divided into control (CON; n = 6) and treatment groups (DSS; n = 5). Both groups were infused with an equal volume of either saline or 1.25 g of DSS · kg BW(-1) · d(-1) in saline, respectively, for 10 d. Enzyme kinetic experiments for IAP, lactase, maltase, SI, MGA, and APN were measured at 37°C with isolated proximal jejunal apical membrane. Target hydrolase protein abundances in the apical membrane were analyzed by Western blotting and their mRNA abundances in the jejunum were measured by quantitative real-time reverse transcription (RT-) PCR with ?-actin as the housekeeping gene. Expressed as percentage of the CON, DSS treatment decreased (P < 0.05) the maximal specific activities of IAP (53%), lactase (78%), maltase (56%), SI (72%), MGA (29%), and APN (22%) as well as the target hydrolase protein abundances of IAP (39%), lactase (35%), SI (36%), and APN (54%), respectively. Decreases (P < 0.05) in the mRNA abundances (% of the CON) for lactase (25%), SI (52%), MGA (75%), and APN (39%) were observed in the DSS group. However, DSS treatment increased (P < 0.05) the jejunal IAP mRNA abundance by 3.5 fold. We conclude that decreases in the small intestinal apical activities of these examined hydrolases likely contribute to overgrowth of pathogenic bacterial populations in the distal small intestine and the colon, leading to the pathogenesis of IBD. PMID:23365358

Lackeyram, D; Mine, Y; Archbold, T; Fan, M Z

2012-12-01

215

Isolation and characterization of sulfite oxidase from Alligator mississipiensis  

SciTech Connect

Sulfite oxidase has been isolated from fresh alligator liver using ammonium sulfate and acetone fractionation, DEAE chromatography and FPLC on Mono Q. The enzyme is dimeric and exhibits a subunit M. Wt. of approximately 58 kDa, larger than that of chicken SO. EPR spectroscopy of the partially-reduced enzyme revealed a single Mo(V) species while visible spectroscopy revealed the presence of cytochrome b{sub 557}. Maximal activities were obtained at pH 8 and 9, respectively. K{sub m}'s for SO{sub 3}{sup 2 {minus}}, cyt. c and Fe(CN){sub 6}{sup 3 {minus}} were 23.5 uM, 2.9 uM and 8.0 uM, respectively. Sequencing of peptides obtained by endoprotease K digestion indicated regions of extensive sequence similarity to chicken and rat enzymes in both heme and Mo-pterin domains. Regions of sequence dissimilarity were also found.

Robbins, A.; Neame, P.J.; Barber, M.J. (Univ. of South Florida College, Tampa (United States))

1991-03-11

216

Oxidation inhibition of sulfite in dual alkali flue gas desulfurization system.  

PubMed

A laboratory-scale well-mixed thermostatic reactor with continuously blasting air was used to investigate the oxidation inhibition of sulfite in dual alkali flue gas desulfurization (FGD) system. The effects of operating parameters such as pH value and catalyst concentration on the oxidation were studied. Sodium thiosulfate was used in the system, and was found that it significantly inhabited the sulfite oxidation. In the absence of catalyst, sodium thiosulfate at 12.67 mmol/L had an inhibition efficiency of approximately 98%. While in the presence of catalyst, sodium thiosulfate at 26.72 mmol/L had an inhibition efficiency less than 85.0%. The oxidation reaction order of sulfite in the sodium thiosulfate was determined to be -1.90 and -0.55 in the absence and presence of the catalyst, respectively. Apparent activation energy of oxidation inhibition was calculated to be 53.9 kJ/mol. Pilot tests showed that the consumption rate of thiosulfate agreed well with the laboratory-scale experimental results. PMID:17915734

Mo, Jian-song; Wu, Zhong-biao; Cheng, Chang-jie; Guan, Bao-hong; Zhao, Wei-rong

2007-01-01

217

Effect of Sodium Lauryl Sulfate-Fumaric Acid Coupled Addition on the In Vitro Rumen Fermentation with Special Regard to Methanogenesis  

PubMed Central

The aim of the current study was to evaluate the effect of sodium lauryl sulfate-fumaric acid coupled addition on in vitro methangenesis and rumen fermentation. Evaluation was carried out using in vitro gas production technique. Ruminal contents were collected from five steers immediately after slaughtering and used for preparation of inoculums of mixed rumen microorganisms. Rumen fluid was then mixed with the basal diet of steers and used to generate four treatments, negative control (no additives), sodium lauryl sulfate (SLS) treated, fumaric acid treated, and SLS-fumaric acid coupled addition treated. The results revealed that, relative to control, efficiency in reduction of methanogenesis was as follows: coupled addition > SLS-addition > fumaric acid addition. Both SLS-addition and SLS-fumaric acid coupled addition demonstrated a decremental effect on ammonia nitrogen (NH3–N), total short chain volatile fatty acids (SCVFAs) concentrations and the amount of substrate degraded, and an increment effect on microbial mass and microbial yield (YATP). Nevertheless, fumaric acid did not alter any of the previously mentioned parameters but induced a decremental effect on NH3–N. Furthermore, both fumaric acid and SLS-fumaric acid coupled addition increased propionate at the expense of acetate and butyrate, while, defaunation increased acetate at the expense of propionate and butyrate. The pH value was decreased by all treatments relative to control, while, cellulase activity did not differ by different treatments. The current study can be promising strategies for suppressing ruminal methane emissions and improving ruminants feed efficiency. PMID:20445794

Abdl-Rahman, M. A.; Sawiress, F. A. R.; Abd El-Aty, A. M.

2010-01-01

218

Use of capillary electrophoresis-sodium dodecyl sulfate to monitor disulfide scrambled forms of an Fc fusion protein during purification process.  

PubMed

Overexpression of recombinant Fc fusion proteins in Escherichia coli frequently results in the production of inclusion bodies that are subsequently used to produce fully functional protein by an in vitro refolding process. During the refolding step, misfolded proteins such as disulfide scrambled forms can be formed, and purification steps are used to remove these product-related impurities to produce highly purified therapeutic proteins. A variety of analytical methods are commonly used to monitor protein variants throughout the purification process. Capillary electrophoresis (CE)-based techniques are gaining popularity for such applications. In this work, we used a nonreduced capillary electrophoresis-sodium dodecyl sulfate (nrCE-SDS) method for the analysis of disulfide scrambled forms in a fusion protein. Under denatured nonreduced conditions, an extra post-shoulder peak was observed at all purification steps. Detailed characterization revealed that the peak was related to the disulfide scrambled forms and was isobaric with the correctly folded product. In addition, when sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was used during the CE-SDS peak characterization, we observed that the migration order of scrambled forms is reversed on CE-SDS versus SDS-PAGE. This illustrates the importance of establishing proper correlation of these two techniques when they are used interchangeably to guide the purification process and to characterize proteins. PMID:21420378

Hapuarachchi, Suminda; Fodor, Szilan; Apostol, Izydor; Huang, Gang

2011-07-15

219

Dextran Sodium Sulfate (DSS) Induces Colitis in Mice by Forming Nano-Lipocomplexes with Medium-Chain-Length Fatty Acids in the Colon  

PubMed Central

Inflammatory bowel diseases (IBDs), primarily ulcerative colitis and Crohn's disease, are inflammatory disorders caused by multiple factors. Research on IBD has often used the dextran sodium sulfate (DSS)-induced colitis mouse model. DSS induces in vivo but not in vitro intestinal inflammation. In addition, no DSS-associated molecule (free glucose, sodium sulfate solution, free dextran) induces in vitro or in vivo intestinal inflammation. We find that DSS but not dextran associated molecules established linkages with medium-chain-length fatty acids (MCFAs), such as dodecanoate, that are present in the colonic lumen. DSS complexed to MCFAs forms nanometer-sized vesicles ?200 nm in diameter that can fuse with colonocyte membranes. The arrival of nanometer-sized DSS/MCFA vesicles in the cytoplasm may activate intestinal inflammatory signaling pathways. We also show that the inflammatory activity of DSS is mediated by the dextran moieties. The deleterious effect of DSS is localized principally in the distal colon, therefore it will be important to chemically modify DSS to develop materials beneficial to the colon without affecting colon-targeting specificity. PMID:22427817

Laroui, Hamed; Ingersoll, Sarah A.; Liu, Hong Chun; Baker, Mark T.; Ayyadurai, Saravanan; Charania, Moiz A.; Laroui, Famina; Yan, Yutao; Sitaraman, Shanthi V.; Merlin, Didier

2012-01-01

220

Applications of pulsed EPR spectroscopy to structural studies of sulfite oxidizing enzymes  

SciTech Connect

Sulfite oxidizing enzymes (SOEs), including sulfite oxidase (SO) and bacterial sulfite dehydrogenase (SDH), catalyze the oxidation of sulfite (SO32?) to sulfate (SO42?). The active sites of SO and SDH are nearly identical, each having a 5-coordinate, pseudo-square-pyramidal Mo with an axial oxo ligand and three equatorial sulfur donor atoms. One sulfur is from a conserved Cys residue and two are from a pyranopterindithiolene (molybdopterin, MPT) cofactor. The identity of the remaining equatorial ligand, which is solvent-exposed, varies during the catalytic cycle. Numerous in vitro studies, particularly those involving electron paramagnetic resonance (EPR) spectroscopy of the Mo(V) states of SOEs, have shown that the identity and orientation of this exchangeable equatorial ligand depends on the buffer pH, the presence and concentration of certain anions in the buffer, as well as specific point mutations in the protein. Until very recently, however, EPR has not been a practical technique for directly probing specific structures in which the solvent-exposed, exchangeable ligand is an O, OH?, H2O, SO32?, or SO42? group, because the primary O and S isotopes (16O and 32S) are magnetically silent (I = 0). This review focuses on the recent advances in the use of isotopic labeling, variable-frequency high resolution pulsed EPR spectroscopy, synthetic model compounds, and DFT calculations to elucidate the roles of various anions, point mutations, and steric factors in the formation, stabilization, and transformation of SOE active site structures.

Klein, Eric L.; Astashkin, Andrei V.; Raitsimring, Arnold; Enemark, John H.

2013-01-01

221

Comparison of microenvironments of aqueous sodium dodecyl sulfate micelles in the presence of inorganic and organic salts: a time-resolved fluorescence anisotropy approach.  

PubMed

Microenvironments of aqueous sodium dodecyl sulfate (SDS) micelles was examined in the presence of additives such as sodium chloride and p-toluidine hydrochloride (PTHC) by monitoring the fluorescence anisotropy decays of two hydrophobic probes, 2,5-dimethyl-1,4-dioxo-3,6-diphenylpyrrolo[3,4-c]pyrrole (DMDPP) and coumarin 6 (C6). It has been well-established that SDS micelles undergo a sphere-to-rod transition and that their mean hydrodynamic radius increases from 19 to 100 A upon the addition of 0.0-0.7 M NaCl at 298 K. A similar size and shape transition is induced by PTHC at concentrations that are 20 times lower compared to that of NaCl. This study was undertaken to find out how the microviscosity of the micelles is influenced under these circumstances. It was noticed that the microviscosity of the SDS/NaCl system increased by approximately 45%, whereas there was a less than 10% variation in the microviscosity of the SDS/PTHC system. The large increase in the microviscosity of the former system with salt concentration has been rationalized on the basis of the high concentration of sodium ions in the headgroup region of the micelles and their ability to strongly coordinate with the water present in this region, which decreases the mobility of the probe molecules. PMID:16262297

Dutt, G B

2005-11-01

222

A quantum-mechanical study of the reaction mechanism of sulfite oxidase.  

PubMed

The oxidation of sulfite to sulfate by two different models of the active site of sulfite oxidase has been studied. Both protonated and deprotonated substrates were tested. Geometries were optimized with density functional theory (TPSS/def2-SV(P)) and energies were calculated either with hybrid functionals and large basis sets (B3LYP/def2-TZVPD) including corrections for dispersion, solvation, and entropy, or with coupled-cluster theory (LCCSD(T0)) extrapolated toward a complete basis set. Three suggested reaction mechanisms have been compared and the results show that the lowest barriers are obtained for a mechanism where the substrate attacks a Mo-bound oxo ligand, directly forming a Mo-bound sulfate complex, which then dissociates into the products. Such a mechanism is more favorable than mechanisms involving a Mo-sulfite complex with the substrate coordinating either by the S or O atom. The activation energy is dominated by the Coulomb repulsion between the Mo complex and the substrate, which both have a negative charge of -1 or -2. PMID:24957901

van Severen, Marie-Céline; Andreji?, Milica; Li, Jilai; Starke, Kerstin; Mata, Ricardo A; Nordlander, Ebbe; Ryde, Ulf

2014-10-01

223

Value-Added Products From FGD Sulfite-Rich Scrubber Materials  

SciTech Connect

Massive quantities of sulfite-rich flue gas desulfurization (FGD) scrubber materials are produced every year in the USA. In fact, at present, the production of wet sulfite-rich scrubber cake outstrips the production of wet sulfate-rich scrubber cake by about 6 million tons per year. However, most of the utilization focus has centered on FGD gypsum. Therefore, we have recently initiated research on developing new strategies for the economical, but environmentally-sound, utilization of sulfite-rich scrubber material. In this exploratory project (Phase I), we attempted to ascertain whether it is feasible to develop reconstituted wood replacement products from sulfite-rich scrubber material. In pursuit of this goal, we characterized two different wet sulfite-rich scrubber materials, obtained from two power plants burning Midwestern coal, for their suitability for the development of value-added products. The overall strategy adopted was to fabricate composites where the largest ingredient was scrubber material with additional crop materials as additives. Our results suggested that it may be feasible to develop composites with flexural strength as high as 40 MPa (5800 psi) without the addition of external polymers. We also attempted to develop load-bearing composites from scrubber material, natural fibers, and phenolic polymer. The polymer-to-solid ratio was limited to {le} 0.4. The formulated composites showed flexural strengths as high as 73 MPa (10,585 psi). We plan to harness the research outcomes from Phase I to develop parameters required to upscale our value-added products in Phase II.

Vivak M. Malhotra

2006-09-30

224

Oxidation of ammonium sulfite in aqueous solutions using ozone technology  

NASA Astrophysics Data System (ADS)

How to deal with unstable ammonium sulfite, the byproduct of flue gas desulfuration by ammonia absorption methods, has been a difficult problem in recent years. Oxidation of ammonium sulfite in aqueous solutions using ozone produced by a surface discharge system was investigated in the paper. The oxidation efficiency of ammonium sulfite by ozone and traditional air aeration were compared, and the factors including ozone concentration, gas flow rate, initial concentration of ammonium sulfite solution and reaction temperature were discussed. The results show that the oxidation efficiency of ammonium sulfite by ozone technology reached nearly 100% under the optimum conditions, which had a significant increase compared with that by air aeration.

Li, Yue; Shang, Kefeng; Lu, Na; Li, Jie; Wu, Yan

2013-03-01

225

Preparation of stable electroneutral nanoparticles of sodium dodecyl sulfate and branched poly(ethylenimine) in the presence of pluronic F108 copolymer.  

PubMed

Mixing of polyelectrolyte solutions with solutions of oppositely charged surfactants usually leads to phase separation in a certain concentration range. However, since the charge-neutralized polyelectrolyte/surfactant nanoparticles might be utilized as versatile nanocarriers of different substances, it would be desirable to prevent their aggregation for some applications. As it was revealed in earlier investigations, the complete suppression of precipitation may be achieved only in mixtures of ionic surfactants and appropriate copolymer polyelectrolytes with nonionic and ionic blocks. In this work, we present a method that could prevent phase separation in mixtures of homopolyelectrolytes and oppositely charged surfactants. Specifically, it is shown that nonaggregating electroneutral nanocomplexes of branched poly(ethylenimine) (PEI) and sodium dodecyl sulfate (SDS) can be prepared in the presence of the amphiphilic triblock copolymer Pluronic F108, provided that an adequate mixing protocol is used for preparation of the PEI/SDS/F108 mixtures. PMID:22050126

Pojják, Katalin; Mészáros, Róbert

2011-12-20

226

Mixed self-assembly of poly(ethylene oxide)-b-poly(epsilon-caprolactone) copolymers and sodium dodecyl sulfate in aqueous solution.  

PubMed

Interaction of amphiphilic poly(ethylene oxide)-b-poly(epsilon-caprolactone) copolymers with anionic sodium dodecyl sulfate (SDS) has been investigated in aqueous solution. Formation of mixed micelles has been confirmed by surface tension measurements, whereas the influence of the surfactant on the copolymer self-assembling has been studied by measurement of the 1H NMR self-diffusion coefficients and by small-angle neutron scattering. As a rule, the surfactant decreases the heterogeneity of the micellar structures formed by the copolymer in water. Moreover, increasing the content of SDS results in the increasingly more important extension of the poly(ethylene oxide) (PEO) corona chains and the copolymer micelle deaggregation. The stability of the micelles against SDS increases with the length of the hydrophobic block. Preliminary two-dimensional NMR measurements with nuclear Overhauser enhancement have confirmed the spatial vicinity between SDS and the constitutive blocks of the copolymer. PMID:15461482

Vangeyte, P; Leyh, B; Auvray, L; Grandjean, J; Misselyn-Bauduin, A-M; Jérôme, R

2004-10-12

227

Use of sodium dodecyl sulfate as an antifouling and homogenizing agent in the direct determination of heavy metals by anodic stripping voltammetry.  

PubMed

The effectiveness of the anionic surfactant sodium dodecyl sulfate (SDS) for suppressing adsorption interferences in anodic stripping voltammetry (ASV) was investigated. The samples included fruit juices, wine, beer, milk powder and waste water, and the analytes were cadmium, lead and copper. In most of the samples, the ASV signals were severely depressed or even absent due to electrode fouling, but addition of SDS in concentrations up to 10 g L(-1) proved effective in restoring the ASV response. By using SDS as an interference suppressor, the content of lead and copper in a milk powder reference material was determined, and the results were in agreement with the certified values. In this determination, which could not have been performed without SDS, the surfactant also served as a homogenizing agent, preventing separation of the sample components. The effect of SDS was explained by the interaction of the surfactant with the electrode surface and with the constituents of the sample matrix. PMID:15284920

Hoyer, Boy; Jensen, Nina

2004-08-01

228

The Effect of Sodium Dodecyl Sulfate (SDS) and Cetyltrimethylammonium Bromide (CTAB) on the Properties of ZnO Synthesized by Hydrothermal Method  

PubMed Central

ZnO nanostructures were synthesized by hydrothermal method using different molar ratios of cetyltrimethylammonium bromide (CTAB) and Sodium dodecyl sulfate (SDS) as structure directing agents. The effect of surfactants on the morphology of the ZnO crystals was investigated by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) techniques. The results indicate that the mixture of cationic-anionic surfactants can significantly modify the shape and size of ZnO particles. Various structures such as flakes, sheets, rods, spheres, flowers and triangular-like particles sized from micro to nano were obtained. In order to examine the possible changes in other properties of ZnO, characterizations like powder X-ray diffraction (PXRD), thermogravimetric and differential thermogravimetric analysis (TGA-DTG), FTIR, surface area and porosity and UV-visible spectroscopy analysis were also studied and discussed. PMID:23202952

Ramimoghadam, Donya; Hussein, Mohd Zobir Bin; Taufiq-Yap, Yun Hin

2012-01-01

229

Phylogenetic and environmental diversity of DsrAB-type dissimilatory (bi)sulfite reductases.  

PubMed

The energy metabolism of essential microbial guilds in the biogeochemical sulfur cycle is based on a DsrAB-type dissimilatory (bi)sulfite reductase that either catalyzes the reduction of sulfite to sulfide during anaerobic respiration of sulfate, sulfite and organosulfonates, or acts in reverse during sulfur oxidation. Common use of dsrAB as a functional marker showed that dsrAB richness in many environments is dominated by novel sequence variants and collectively represents an extensive, largely uncharted sequence assemblage. Here, we established a comprehensive, manually curated dsrAB/DsrAB database and used it to categorize the known dsrAB diversity, reanalyze the evolutionary history of dsrAB and evaluate the coverage of published dsrAB-targeted primers. Based on a DsrAB consensus phylogeny, we introduce an operational classification system for environmental dsrAB sequences that integrates established taxonomic groups with operational taxonomic units (OTUs) at multiple phylogenetic levels, ranging from DsrAB enzyme families that reflect reductive or oxidative DsrAB types of bacterial or archaeal origin, superclusters, uncultured family-level lineages to species-level OTUs. Environmental dsrAB sequences constituted at least 13 stable family-level lineages without any cultivated representatives, suggesting that major taxa of sulfite/sulfate-reducing microorganisms have not yet been identified. Three of these uncultured lineages occur mainly in marine environments, while specific habitat preferences are not evident for members of the other 10 uncultured lineages. In summary, our publically available dsrAB/DsrAB database, the phylogenetic framework, the multilevel classification system and a set of recommended primers provide a necessary foundation for large-scale dsrAB ecology studies with next-generation sequencing methods.The ISME Journal advance online publication, 24 October 2014; doi:10.1038/ismej.2014.208. PMID:25343514

Müller, Albert Leopold; Kjeldsen, Kasper Urup; Rattei, Thomas; Pester, Michael; Loy, Alexander

2014-10-24

230

VOLATILE COMPONENT RECOVERY FROM SULFITE EVAPORATOR CONDENSATE  

EPA Science Inventory

This study is on the operation and modification of a demonstration unit to remove sulfur dioxide, methanol, furfural, and acetic acid from its sulfite evaporator condensate. This unit consisted of a steam stripper, vent tank SO2 recovery, activated carbon adsorption columns, and ...

231

Acids in combination with sodium dodecyl sulfate caused quality deterioration of fresh-cut iceberg lettuce during storage in modified atmosphere package.  

PubMed

Recent studies showed that sodium acid sulfate (SAS) and levulinic acid (LA) in combination with sodium dodecyl sulfate (SDS) was effective in inactivating human pathogens on Romaine lettuce. The present study investigated the effects of LA and SAS in combination with SDS (as compared with citric acid and chlorine) on the inactivation of E. coli O157:H7 and sensory quality of fresh-cut Iceberg lettuce in modified atmosphere packages during storage at 4 °C. Results showed that LA (0.5% to 3%) and SAS (0.25% to 0.75%) with 0.05% SDS caused detrimental effects on visual quality and texture of lettuce. LA- and SAS-treated samples were sensorially unacceptable due to development of sogginess and softening after 7 and 14 d storage. It appears that the combined treatments caused an increase in the respiration rate of fresh-cut lettuce as indicated by higher CO(2) and lower O(2) in modified atmosphere packages. On the positive side, the acid treatments inhibited cut edge browning of lettuce pieces developed during storage. LA (0.5%), SAS (0.25%), and citric acid (approximately 0.25%) in combination with SDS reduced population of E. coli OH157:H7 by 0.41, 0.87, and 0.58 log CFU/g, respectively, while chlorine achieved a reduction of 0.94 log CFU/g without damage to the lettuce. Therefore, compared to chlorine, LA and SAS in combination with SDS have limited commercial value for fresh-cut Iceberg lettuce due to quality deterioration during storage. PMID:21535517

Guan, Wenqiang; Huang, Lihan; Fan, Xuetong

2010-10-01

232

Effect of pH, surface charge and counter-ions on the adsorption of sodium dodecyl sulfate to the sapphire/solution interface  

E-print Network

The role of ionic interactions between sodium dodecyl sulfate, SDS, and sapphire surfaces have been studied using specular neutron reflection to determine the structure and composition of adsorbed surfactant layers. Increasing the pH of the solution from 3 to 9 reduces the adsorption by reversing the charge of the alumina. This occurs at lower pH for the R-plane (1 -1 0 2) than the C-plane (0 0 0 1), corresponding to the different points of zero charge. The largest surface excess is about 6.5 micromol m-2, the thickness of the adsorbed layer is about 24 Angstrom and it contains roughly 20% water. The hydrocarbon tails of the surfactant molecules clearly interpenetrate rather than form an ordered bilayer. The structure is similar in either pure water or in 0.1 M NaCl when the surfactant is at the respective critical micelle concentration. Different structures were seen with lithium and cesium dodecyl sulfate. The CsDS forms dense layers with little or no hydration and a surface excess of about 10.5 micromol m-2. The metal cation strongly influences the hydration of the adsorbed surfactant. An overall picture of 'flattened micelles' for the structure of the adsorbed layer is observed

Ningning Li; Robert K. Thomas; Adrian R. Rennie

2012-05-01

233

Bowman-Birk Inhibitor Concentrate Reduces Colon Inflammation in Mice with Dextran Sulfate Sodium-Induced Ulcerative Colitis  

Microsoft Academic Search

Bowman-Birk inhibitor concentrate (BBIC) is asoybean extract enriched in the BowmanBirk inhibitor, aprotein protease inhibitor. The Bowman-Birk inhibitorcan inhibit proteases released from inflammation mediating cells and suppress superoxide anionradical secretion from immunocytes. This studyinvestigates the ability of Bowman-Birk inhibitorconcentrate to inhibit colon inflammation in the dextransulfate sodium model of ulcerative colitis, aninflammatory bowel disease. When compared to mice on astandard

Jeffrey H. Ware; X. Steven Wan; Paul Newberne; Ann R. Kennedy

1999-01-01

234

Stable isotope studies of vent fluids and chimney minerals, southern Juan de Fuca Ridge: Sodium metasomatism and seawater sulfate reduction  

SciTech Connect

Sulfur isotope values (delta/sup 34/S) or H/sub 2/S in vent fluids from the southern Juan de Fuca Ridge hydrothermal sites range from 4.0 to 7.4% and are variably /sup 34/S-enriched with respect to coexisting inner wall chimney sulfides. Chimney sulfides range from 1.6 to 5.7%. The chimneys consist of Fe-sphalerite zoned to inner zinc sulfide and chalcopyrite ( +- isocubanite)-pyrrhotite lining channels. Sulfide from inner walls of type A chimneys have the lightest delta/sup 34/S values. Type B chimneys (porous, unzoned, low-Fe-sphalerite) have the isotopically heaviest chimney sulfides and occur at vent sites distal to the along-axis shallow point of the ridge crest, hence distal to the magma chamber. These variations are largely ascribed to sulfate reduction by ferrous iron in the hydrothermal fluid in chimneys of substrate mounds, probably due to transitory entrainment of ambient sulfate-bearing seawater. The delta/sup 18/O values of end-member hydrothermal fluids range from 0.6 to 0.8%, significantly lower than the delta/sup 18/O values at 21 /sup 0/N vent fluids. The deltaD values of the fluid samples range from -2.5 to 0.5%. Isotopic differences from the 21 /sup 0/N fluids may be due to slightly higher water/rock ratios, approximately 1.0, in the southern Juan de Fuca Ridge hydrothermal system. Admixture of a small amount of residual brine from an earlier phase separation even may have contributed water with low deltaD values.

Shanks W.C. III; Seyfried W.E. Jr.

1987-10-10

235

Labile sulfide and sulfite in phytochelatin complexes  

SciTech Connect

Heavy metals such as cadmium induce tomato cell cultures to synthesize the metal binding polypeptides ({gamma}-Glu-Cys){sub 3} and ({gamma}-Glu-Cys){sub 4}-Gly (phytochelatins). Tomato cells selected for growth on normally lethal concentrations of CdCl{sub 2} synthesize higher quantities of these polypeptides. Cd{sup r} cells are not cross-resistant to other heavy metals, and recent work suggests that metal detoxification by these peptides may be Cd-specific. The occurrence of labile sulfur as a component of the metal complex raises questions concerning possible functions of phytochelatins besides that of Cd binding. The presence of acid-labile sulfide ion in phytochelatin complexes has been reported by several groups. We report the additional finding that labile sulfite is also present in these complexes and in higher amounts than sulfide. Sulfide and sulfite are both released from the metal binding complex by acidification or by treatment with EDTA.

Eannetta, N.T.; Steffens, J.C. (Cornell Univ., Ithaca, NY (USA))

1989-04-01

236

Upregulation of P-glycoprotein by probiotics in intestinal epithelial cells and in the dextran sulfate sodium model of colitis in mice.  

PubMed

P-glycoprotein (P-gp) mediates efflux of xenobiotics and bacterial toxins from the intestinal mucosa into the lumen. Dysregulation of P-gp has been implicated in inflammatory bowel disease. Certain probiotics have been shown to be effective in treating inflammatory bowel disease. However, direct effects of probiotics on P-gp are not known. Current studies examined the effects of Lactobacilli on P-gp function and expression in intestinal epithelial cells. Caco-2 monolayers and a mouse model of dextran sulfate sodium-induced colitis were utilized. P-gp activity was measured as verapamil-sensitive [(3)H]digoxin transepithelial flux. Multidrug resistant 1 (MDR1)/P-gp expression was measured by real-time quantitative PCR and immunoblotting. Culture supernatant (CS; 1:10 or 1:50, 24 h) of Lactobacillus acidophilus or Lactobacillus rhamnosus treatment of differentiated Caco-2 monolayers (21 days postplating) increased (?3-fold) MDR1/P-gp mRNA and protein levels. L. acidophilus or L. rhamnosus CS stimulated P-gp activity (?2-fold, P < 0.05) via phosphoinositide 3-kinase and ERK1/2 MAPK pathways. In mice, L. acidophilus or L. rhamnosus treatment (3 × 10(9) colony-forming units) increased mdr1a/P-gp mRNA and protein expression in the ileum and colon (2- to 3-fold). In the dextran sulfate sodium (DSS)-induced colitis model (3% DSS in drinking water for 7 days), the degree of colitis as judged by histological damage and myeloperoxidase activity was reduced by L. acidophilus. L. acidophilus treatment to DSS-treated mice blocked the reduced expression of mdr1a/P-gp mRNA and protein in the distal colon. These findings suggest that Lactobacilli or their soluble factors stimulate P-gp expression and function under normal and inflammatory conditions. These data provide insights into a novel mechanism involving P-gp upregulation in beneficial effects of probiotics in intestinal inflammatory disorders. PMID:21350189

Saksena, Seema; Goyal, Sonia; Raheja, Geetu; Singh, Varsha; Akhtar, Maria; Nazir, Talat M; Alrefai, Waddah A; Gill, Ravinder K; Dudeja, Pradeep K

2011-06-01

237

Variation and Genomic Localization of Genes Encoding DROSOPHILA MELANOGASTER Male Accessory Gland Proteins Separated by Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis  

PubMed Central

Accessory gland proteins from Drosophila melanogaster males have been separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis into nine major bands. When individual males from 175 strains were examined, considerable polymorphism for nearly one-half of the major protein bands was seen, including null alleles for three bands. Variation was observed not only among long-established laboratory strains but also among stocks recently derived from natural populations. There was little difference in the amount of variation between P and M strains, indicating that P element mutagenesis is not a factor producing the variation. Codominant expression of variants for each of five bands was found in heterozygotes, suggesting structural gene variation and not posttranslational modification variation. Stocks carrying electrophoretic variants of four of the major proteins were used to map the presumed structural genes for these proteins; the loci were found to be dispersed on the second chromosome. Since males homozygous for variant proteins were fertile, the polymorphism seems to have little immediate effect on successful sperm transfer. We propose that a high degree of polymorphism can be tolerated because these proteins play a nutritive rather than enzymatic role in Drosophila reproduction. PMID:3095182

Whalen, Michael; Wilson, Thomas G.

1986-01-01

238

Adsorption of the anionic surfactant sodium dodecyl sulfate on a C18 column under micellar and high submicellar conditions in reversed-phase liquid chromatography.  

PubMed

Micellar liquid chromatography makes use of aqueous solutions or aqueous-organic solutions containing a surfactant, at a concentration above its critical micelle concentration. In the mobile phase, the surfactant monomers aggregate to form micelles, whereas on the surface of the non-polar alkyl-bonded stationary phases they are significantly adsorbed. If the mobile phase contains a high concentration of organic solvent, micelles breakdown and the amount of surfactant adsorbed on the stationary phase is reduced, giving rise to another chromatographic mode named high submicellar liquid chromatography. The presence of a thinner coating of surfactant enhances the selectivity and peak shape, especially for basic compounds. However, the risk of full desorption of surfactant is the main limitation in the high submicellar mode. This study examines the adsorption of the anionic surfactant sodium dodecyl sulfate under micellar and high submicellar conditions on a C18 column, applying two methods. One of them uses a refractive index detector to obtain direct measurements of the adsorbed amount of SDS, whereas the second method is based on the retention and peak shape for a set of cationic basic compounds that indirectly reveal the presence of adsorbed monomers of surfactant on the stationary phase. This article is protected by copyright. All rights reserved. PMID:25476819

Ortiz-Bolsico, C; Ruiz-Angel, M J; García-Alvarez-Coque, M C

2014-12-01

239

Transport Pathways and Enhancement Mechanisms within Localized and Non-Localized Transport Regions in Skin Treated with Low-Frequency Sonophoresis and Sodium Lauryl Sulfate  

PubMed Central

Recent advances in transdermal drug delivery utilizing low-frequency sonophoresis (LFS) and sodium lauryl sulfate (SLS) have revealed that skin permeability enhancement is not homogenous across the skin surface. Instead, highly perturbed skin regions, known as localized transport regions (LTRs), exist. Despite these findings, little research has been conducted to identify intrinsic properties and formation mechanisms of LTRs and the surrounding less-perturbed non-LTRs. By independently analyzing LTR, non-LTR, and total skin samples treated at multiple LFS frequencies, we found that the pore radii (rpore) within non-LTRs are frequency-independent, ranging from 18.2 – 18.5 Å, but significantly larger than rpore of native skin samples (13.6 Å). Conversely, rpore within LTRs increases significantly with decreasing frequency from 161 Å, to 276 Å, and to ? (>300Å) for LFS/SLS-treated skin at 60 kHz, 40 kHz, and 20 kHz, respectively. Our findings suggest that different mechanisms contribute to skin permeability enhancement within each skin region. We propose that the enhancement mechanism within LTRs is the frequency-dependent process of cavitation-induced microjet collapse at the skin surface, while the increased rpore values in non-LTRs are likely due to SLS perturbation, with enhanced penetration of SLS into the skin resulting from the frequency-independent process of microstreaming. PMID:20740667

Polat, Baris E.; Figueroa, Pedro L.; Blankschtein, Daniel; Langer, Robert

2011-01-01

240

Anti-colitic effects of kanjangs (fermented soy sauce and sesame sauce) in dextran sulfate sodium-induced colitis in mice.  

PubMed

This study was conducted to investigate the preventive effects of different kanjangs (Korean soy sauces), including acid-hydrolyzed soy sauce (AHSS), fermented soy sauce (FSS), and fermented sesame sauce (FSeS), on 2% dextran sulfate sodium (DSS)-induced ulcerative colitis in C57BL/6J mice. The fermented sauces, particularly FSeS, significantly suppressed DSS-induced body weight loss, increased colon length, and decreased colon weight/length ratios. Histological observations suggested that the fermented sauces prevented edema, mucosal damage, and the loss of crypts induced by DSS compared to the control mice and animals fed AHSS. FSeS and FSS decreased the serum levels of tumor necrosis factor-? (TNF-?), interferon-? (IFN-?), interleukin (IL)-6, and IL-17?. mRNA expression of these cytokines as well as that of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in colon mucosa was also inhibited by the two sauces. Our results suggest that fermented sauces, especially FSeS, exert an anticolitic effect partially by reducing the serum levels of proinflammatory cytokines and inhibiting the mRNA expression of these factors in the colon tissue of mice treated with DSS. However, AHSS did not protect against DSS-induced colitis. In addition, low-dose treatment (4?mL/kg) with the fermented sauces resulted in greater anticolitic effects than consumption of a high quantity (8?mL/kg) of the sauces. PMID:25188463

Song, Jia-Le; Choi, Jung-Ho; Seo, Jae-Hoon; Lim, Yaung-Iee; Park, Kun-Young

2014-09-01

241

The effects of dodecyl maltoside and sodium dodecyl sulfate surfactants on the stability and aggregation of recombinant interferon Beta-1b.  

PubMed

Aggregation often occurs during manufacturing and storage of protein drugs. Detergents such as sodium dodecyl sulfate are commonly used to prevent aggregation but need to be eliminated before final formulation for safety reasons. We studied the ability of dodecylmaltoside (DDM), a nontoxic alkyl saccharide surfactant, to reduce aggregation and increase the stability of interferon beta-1b (IFN)-?-1b. An increase of 8°C in the Tm of IFN-?-1b was observed when 0.1% of DDM was present in the protein solution. The absorption of DDM on hydrophobic surfaces of IFN-?-1b enables the surface to become hydrophilic and non-ionic, and increases the stability of the protein. 0.1% DDM also results in a 62% increase in helical and a 25% decrease in ?-sheet structures. 0.1% DDM not only suppresses aggregate formation but also improves IFN-?-1b solubilization. Furthermore, we have showed the protective effect of DDM on the anti-viral activity of IFN-?-1b in solution. PMID:24956236

Haji Abdolvahab, Mohadeseh; Fazeli, Ahmad; Fazeli, Mohammad Reza; Brinks, Vera; Schellekens, Huub

2014-11-01

242

Polyelectrolyte-surfactant complexes of poly[3,5-bis(dimethylaminomethyl)-4-hydroxystyrene]-block-poly(ethylene oxide) and sodium dodecyl sulfate: anomalous self-assembly behavior.  

PubMed

Polyelectrolyte-surfactant complexes (PE-S) formed by double hydrophilic cationic polyelectrolyte poly[3,5-bis(dimethylaminomethyl)-4-hydroxystyrene]-block-poly(ethylene oxide) (NPHOS-PEO) and anionic surfactant sodium dodecyl sulfate (SDS) in acidic aqueous solutions were studied by light scattering, SAXS, and scanning transmission electron microcopy in the environmental mode (wet-STEM) for various stoichiometric ratios between the numbers of SDS anions and dimethylaminomethyl groups of NPHOS in the complex. The obtained results show that the NPHOS-PEO/SDS system behaves differently from other systems of double hydrophilic block polyelectrolyte and oppositely charged ionic surfactant because it forms water-insoluble PE-S for compositions close to the zero net charge of the complex. This phase separation occurs, instead of the PE-S rearrangement to core-shell particles, which is hindered due to conformational rigidity of the NPHOS blocks. For the surfactant amounts below and above the precipitation region, large spherical aggregates and their clusters are present in the solution. SAXS measurements indicate that although the NPHOS-PEO/SDS system does not form the core-shell particles with the NPHOS/SDS core and the PEO shell as other PE-S of double hydrophilic polyelectrolytes, the aggregates contain domains of closely packed surfactant micelles which bind to both NPHOS polyelectrolyte blocks and PEO blocks. PMID:23590563

Hajduová, Jana; Procházka, Karel; Slouf, Miroslav; Angelov, Borislav; Mountrichas, Grigoris; Pispas, Stergios; St?pánek, Miroslav

2013-05-01

243

A rapid method of species identification of wild chironomids (Diptera: Chironomidae) via electrophoresis of hemoglobin proteins in sodium dodecyl sulfate polyacrylamide gel (SDS-PAGE).  

PubMed

Studying aquatic benthic macroinvertebrates (BMIs) in the field requires accurate taxonomic identification, which can be difficult and time consuming. Conventionally, head capsule morphology has been used to identify wild larvae of Chironomidae. However, due to the number of species and possible damage and/or deformity of their head capsules, another supporting approach for identification is needed. Here, we provide hemoglobin (Hb) protein in hemolymph of chironomids as a new biomarker that may help resolve some of the ambiguities and difficulties encountered during taxonomic identification. Chironomids collected from two locations in Maine and New Jersey, USA were identified to the genus level and in some cases to the species-level using head capsule and body morphologies. The head capsule for a particular individual was then associated with a corresponding Hb protein profile generated from sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Distinct Hb profiles were observed from one group (Thienemannimyia) and four genera (Chironomus, Cricotopus, Dicrotendipes, and Glyptotendipes) of chironomids. Several species were polymorphic, having more than one Hb profile and/or having bands of the same size as those of other species. However, major bands and the combination of bands could distinguish individuals at the genus and sometimes species-level. Overall, this study showed that Hb profiles can be used in combination with head capsule morphology to identify wild chironomids. PMID:24923437

Oh, J T; Epler, J H; Bentivegna, C S

2014-10-01

244

Acetylsalicylic Acid Reduces the Severity of Dextran Sodium Sulfate-Induced Colitis and Increases the Formation of Anti-Inflammatory Lipid Mediators  

PubMed Central

The role of non-steroidal anti-inflammatory drugs in inflammatory bowel disease is controversial, as they have been implicated in disease aggravation. Different from other cyclooxygenase inhibitors, acetylsalicylic acid (ASA) enhances the formation of anti-inflammatory and proresolution lipoxins derived from arachidonic acid as well as resolvins from omega-3 polyunsaturated fatty acids such as docosahexaenoic acid (DHA). In this study, we examined the effect of ASA on murine dextran sodium sulfate colitis. A mouse magnetic resonance imaging (MRI) protocol and post mortem assessment were used to assess disease severity, and lipid metabolites were measured using liquid chromatography-coupled tandem mass spectrometry. Decreased colitis activity was demonstrated by phenotype and MRI assessment in mice treated with ASA, and confirmed in postmortem analysis. Analysis of lipid mediators showed sustained formation of lipoxin A4 and an increase of DHA-derived 17-hydroxydocosahexaenoic acid (17-HDHA) after treatment with ASA. Furthermore, in vitro experiments in RAW264.7 murine macrophages demonstrated significantly increased phagocytosis activity after incubation with 17-HDHA, supporting its proresolution effect. These results show a protective effect of ASA in a murine colitis model and could give a rationale for a careful reassessment of ASA therapy in patients with inflammatory bowel disease and particularly ulcerative colitis, possibly combined with DHA supplementation. PMID:24083240

Köhnke, Thomas; Bilal, Süleyman; Zhou, Xiangzhi; Rothe, Michael; Baumgart, Daniel C.; Weylandt, Karsten H.

2013-01-01

245

Characterization of sodium dodecyl sulfate modified iron pillared montmorillonite and its application for the removal of aqueous Cu(II) and Co(II).  

PubMed

Anionic surfactant modified Fe-pillared montmorillonites were prepared by Fe-hydrate solution and sodium dodecyl sulfate (SDS) solution. These organo-inorgano complex montmorillonites were divided into three types (CM1, CM2 and CM3) depending on different intercalation processes. X-ray diffraction spectra, the Fourier transform infrared (FTIR) spectra were used to analyze the structure of the raw and modified montmorillonites. X-ray photoelectron spectra of the samples have been studied to determine spectral characteristics to allow the identification of Fe(III) hydroxide. The specific surface area of the host montmorillonite (M0) is 73.2m(2)/g, while for the modified montmorillonites it is 114.0m(2)/g, 117.2m(2)/g, and 115.8m(2)/g, respectively. The mesopore volumes of the montmorillonites decrease after modification. Ions of copper and cobalt were selected as adsorbates to evaluate the adsorption performance of each montmorillonite. The adsorption data was analyzed by both Freundlich and Langmuir isotherm models and the data was well fit by the Langmuir isotherm model. The adsorption was efficient and significantly influenced by metal speciation, metal concentration, contact time, and pH. Higher adsorption capacity of the modified montmorillonites were obtained at pH 5-6. The results of desorption indicated that the metal ions were covalently bound to the modified montmorillonites. PMID:19748730

Li, Shu-Zhen; Wu, Ping-Xiao

2010-01-15

246

Ethanol Extract of Cordyceps militaris Grown on Germinated Soybeans Attenuates Dextran-Sodium-Sulfate- (DSS-) Induced Colitis by Suppressing the Expression of Matrix Metalloproteinases and Inflammatory Mediators  

PubMed Central

The effect of Cordyceps militaris (CM) grown on germinated soybeans (GSC) in the inflammatory bowel disease (IBD) model was studied. To demonstrate the preventive effect of GSC extract in a dextran-sodium-sulfate- (DSS-) induced acute colitis mouse model, GSC was administered 2 days before DSS coadministration. GSC significantly suppressed DSS-induced disease activity index (DAI) as well as histopathological scores, compared to control or CM-treated group. To elucidate the anti-IBD activity of GSC, we checked the level of matrix metalloproteinases (MMPs) and inflammatory mediators. GSC extract decreased the level of MMP-3 and -9 mRNAs and p53 proteins. The level and activity of LPS-induced MMP-9 were reduced in GSC-treated RAW264.7 cells. It also attenuated the level of inducible nitric oxide synthase (iNOS) and tumor necrosis factor- (TNF-) ? mRNAs both in colon tissue and in macrophage cells. These results suggest that GSC can be applied as a protective agent against IBDs. PMID:23841050

Park, Dong Ki; Park, Hye-Jin

2013-01-01

247

Sodium sulfate-induced corrosion of pure nickel and superalloy Udimet 700 in a high velocity burner rig at 900 C  

NASA Technical Reports Server (NTRS)

Sodium sulfate-induced corrosion of pure nickel and a commercial nickel-base superalloy, Udimet 700 (U-700), were studied at 900 C in a Mach 0.3 burner rig with different Na levels in the combustor. The corrosion rate of Ni was independent of the Na level in the combustor and considerably lower than that measured in laboratory salt spray tests. The lower rates are associated with the deposition of only a small amount of Na2SO4 on the surface of the NiO scale. Corrosion of U-700 was observed to occur in two stages. During the first stage, the corrosion proceeds by reaction of Cr2O3 scale with the Na2SO4 and evaporation of the Na2CrO4 reaction product from the surface of the corroding sample. Cr depletion in the alloy occurs and small sulfide particles are formed in the Cr depletion zone. Extensive sulfidation occurs during the second state of corrosion, and a thick scale forms. The relationship between the corrosion rate of U-700 and the Na level in the combustor gives a good correlation in the range of 0.3 to 1.5 ppm by weight Na. Very low levels of Na in the combustor cause accelerated oxidation of U-700 without producing the typical hot corrosion morphology.

Misra, A. K.

1987-01-01

248

Inhibitory effects of resistant starch (RS3) as a carrier for stachyose on dextran sulfate sodium-induced ulcerative colitis in C57BL/6 mice  

PubMed Central

The aim of this study was to determine the effects of resistant starch 3 (RS3) as a carrier for stachyose on dextran sulfate sodium (DSS)-induced colitis in C57BL/6 mice. RS3 microspheres carrying stachyose (RS3 + stachyose) were produced and evaluated as a potentially improved colitis therapy for this study. The body weights of the mice treated with RS3 + stachyose were higher compared with those of DSS-treated control mice. RS3 + stachyose reduced the levels of the serum pro-inflammatory cytokines IL-6 and TNF-? to a greater extent compared with the same concentration of stachyose combined with ordinary starch (stachyose + starch). Histopathological examination of sections of colon tissues showed that the RS3 + stachyose group recovered well from colitis; however, the tissue sections of the stachyose + starch group presented necrosis to a more serious degree. These results suggest that stachyose with an RS3 carrier has better preventative effects on colitis than stachyose alone in mice. PMID:24223664

QIAN, YU; ZHAO, XIN; SONG, JIA-LE; ZHU, KAI; SUN, PENG; LI, GUI-JIE; WANG, RUI; KAN, JIAN-QUAN

2013-01-01

249

Artemisinin protects against dextran sulfate-sodium-induced inflammatory bowel disease, which is associated with activation of the pregnane X receptor.  

PubMed

Artemisinin has been used to treat malaria for centuries in the context of traditional Chinese medicine. In the present study, the effects of artemisinin on pregnane X receptor (PXR)-mediated CYP3A expression and its therapeutic role in inflammatory bowel disease were investigated. LS174T cells exposed to artemisinin at various concentrations and for different periods of time were examined with respect to the specific induction of CYP3A4 and PXR mRNA expression. Transient transfection experiments showed transcriptional activation of the CYP3A4 gene through artemisinin to be PXR-dependent. An electrophoretic-mobility shift assay (EMSA) showed that artemisinin activates the DNA-binding capacity of the PXR for the CYP3A4 element. These results indicate that the induction of CYP3A4 by artemisinin is mediated through the activation of PXR. Using animal models, it was demonstrated that artemisinin abrogates dextran sulfate sodium (DDS)-induced intestinal inflammation. Preadministration of artemisinin ameliorated the clinical hallmarks of colitis in DSS-treated mice as determined by body weight loss and assessment of diarrhea, rectal bleeding, colon length, and histology. Artemisinin was found to prevent or reduce the severity of colonic inflammation by inducing CYP3A expression by activation of PXR. PMID:24886881

Hu, Donghua; Wang, Yuguang; Chen, Zhiwu; Ma, Zengchun; You, Qing; Zhang, Xianxie; Zhou, Tao; Xiao, Yong; Liang, Qiande; Tan, Hongling; Xiao, Chengrong; Tang, Xianglin; Zhang, Boli; Gao, Yue

2014-09-01

250

Role of ?-lipoic acid in dextran sulfate sodium-induced ulcerative colitis in mice: studies on inflammation, oxidative stress, DNA damage and fibrosis.  

PubMed

Ulcerative colitis affects many people worldwide. Inflammation and oxidative stress play a vital role in its pathogenesis. Previously, we reported that ulcerative colitis leads to systemic genotoxicity in mice. The present study was aimed at elucidating the role of ?-lipoic acid in ulcerative colitis-associated local and systemic damage in mice. Experimental colitis was induced using 3%w/v dextran sulfate sodium in drinking water for 2 cycles. ?-Lipoic acid was administered in a co-treatment (20, 40, 80 mg/kg bw) and post-treatment (80 mg/kg bw) schedule. Various biochemical parameters, histological evaluation, comet and micronucleus assays, immunohistochemistry and western blot analysis were employed to evaluate the effect of ?-lipoic acid in mice with ulcerative colitis. The protective effect of ?-lipoic acid was mediated through the modulation of nuclear factor kappa B, cyclooxygenase-2, interleukin 17, signal transducer and activator of transcription 3, nuclear erythroid 2-related factor 2, NADPH: quinone oxidoreductase-1, matrix metalloproteinase-9 and connective tissue growth factor. Further, ulcerative colitis led to an increased gut permeability, plasma lipopolysaccharide level, systemic inflammation and genotoxicity in mice, which was reduced with ?-lipoic acid treatment. The present study identifies the underlying mechanisms involved in ?-lipoic acid-mediated protection against ulcerative colitis and the associated systemic damage in mice. PMID:23793040

Trivedi, P P; Jena, G B

2013-09-01

251

Coupling sodium dodecyl sulfate-capillary polyacrylamide gel electrophoresis with matrix-assisted laser desorption ionization time-of-flight mass spectrometry via a poly(tetrafluoroethylene) membrane.  

PubMed

Sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE) is a fundamental analytical technique for proteomic research, and SDS-capillary gel electrophoresis (CGE) is its miniaturized version. Compared to conventional slab-gel electrophoresis, SDS-CGE has many advantages such as increased separation efficiency, reduced separation time, and automated operation. SDS-CGE is not widely accepted in proteomic research primarily due to the difficulties in identifying the well-resolved proteins. MALDI-TOF-MS is an outstanding platform for protein identifications. Coupling the two would solve the problem but is extremely challenging because the MS detector has no access to the SDS-CGE-resolved proteins and the SDS interferes with MS detection. In this work we introduce an approach to address these issues. We discover that poly(tetrafluoroethylene) (PTFE) membranes are excellent materials for collecting SDS-CGE-separated proteins. We demonstrate that we can wash off the SDS bound to the collected proteins and identify these proteins on-membrane with MALDI-TOF-MS. We also show that we can immunoblot and Coomassie-stain the proteins collected on these membranes. PMID:21309548

Lu, Joann J; Zhu, Zaifang; Wang, Wei; Liu, Shaorong

2011-03-01

252

Characterization of Growth, Water Relations, and Proline Accumulation in Sodium Sulfate Tolerant Callus of Brassica napus L. cv Westar (Canola) 1  

PubMed Central

Unselected and sodium sulfate tolerant callus cultures of Brassica napus L. cv Westar were grown on media supplemented with mannitol, NaCl, or Na2SO4. In all cases, growth of tolerant callus, measured on a fresh weight or dry weight basis, was greater than that of unselected callus, which was also subject to necrosis on high levels of salt. Tissue water potential became more negative in both unselected and tolerant callus grown in the presence of mannitol or Na2SO4. Water potentials in unselected callus were more negative than those of the tolerant tissues; but over a range of Na2SO4 concentrations both cultures displayed osmotic adjustment, maintaining relatively constant turgor. Proline accumulation in both unselected and tolerant callus was low (15 to 20 micromoles per gram dry weight) in the absence of stress, but increased on media supplemented with mannitol, NaCl, or Na2SO4. Increases in proline concentration were approximately linear in tolerant callus, reaching a maximum of 130 to 175 micromoles per gram dry weight. In unselected callus, concentrations were higher, reaching 390 to 520 micromoles per gram dry weight. Proline accumulation was correlated with inhibition of growth, and there was a negative correlation between proline concentration and culture age for tolerant callus. PMID:16665381

Chandler, Stephen F.; Thorpe, Trevor A.

1987-01-01

253

Attenuation by dietary taurine of dextran sulfate sodium-induced colitis in mice and of THP-1-induced damage to intestinal Caco-2 cell monolayers.  

PubMed

The effects of dietary taurine on the experimental colitis induced by dextran sulfate sodium (DSS) in mice were evaluated. C57BL/6 female mice were given 3% DSS in drinking water for 5 d to induce acute colitis. Taurine at 2% was added to the drinking water 5 d before and during the DSS-treatment to investigate its preventive effect. Taurine supplementation significantly attenuated the weight decrease, diarrhea severity, colon shortening, and the increase in the colonic tissue myeloperoxidase activity induced by DSS. Taurine also significantly inhibited the increase in the expression of a pro-inflammatory chemokine, macrophage inflammatory protein 2 (MIP-2), but not of interleukin (IL)-1beta or tumor necrosis factor (TNF)-alpha mRNA. Furthermore, taurine significantly protected the intestinal Caco-2 cell monolayers from the damage by macrophage-like THP-1 cells in an in vitro coculture system. These results suggest that taurine prevented DSS-induced colitis partly in association with (1) its inhibitory effects on the secretion of MIP-2 from the intestinal epithelial cells and on the infiltration of such inflammatory cells as neutrophils and (2) its cytoprotective functions on the epithelial barrier from the direct toxicity of DSS and from the inflammatory cell-induced injury. PMID:17619120

Zhao, Z; Satsu, H; Fujisawa, M; Hori, M; Ishimoto, Y; Totsuka, M; Nambu, A; Kakuta, S; Ozaki, H; Shimizu, M

2008-06-01

254

Chemiluminescence analysis of menadione sodium bisulfite and analgin in pharmaceutical preparations and biological fluids  

Microsoft Academic Search

A novel chemiluminescence (CL) flow system for two sulfite-containing drugs, namely, menadione sodium bisulfite (MSB) and analgin is described. It is based on the weak chemiluminescence induced by the oxidation of sulfite group in drugs with dissolved oxygen in the presence of acidic Rh6G. Tween 80 surfactant micelles showed a strong enhancement effect on this weak chemiluminescence. For MSB analysis,

Yuming Huang; Chao Zhang; Xinrong Zhang; Zhujun Zhang

1999-01-01

255

Production of basic chromium sulfate by using recovered chromium from ashes of thermally treated leather.  

PubMed

Leather wastes tanned with chromium are generated during the production process of leather, hence the wastes from hand crafted goods and footwear industries are a serious environmental problem. The thermal treatment of leather wastes can be one of the treatment options because the wastes are rich in chromium and can be used as a raw material for sodium chromate production and further to obtain several chromium compounds. The objective of this study was to utilize the chromium from leather wastes via basic chromium sulfate production to be subsequently applied in a hide tanning. The obtained results have shown that this is the first successful attempt to achieve desired base properties of the product. The result was achieved when the following conditions were applied: a molar ratio between sodium sulfite and sodium dichromate equal to 6; reaction time equal to 5 min before addition of sulfuric acid; pH of sodium dichromate solution equal to 2. Summarizing, there is an opportunity to utilize the dangerous wastes and reused them in the production scheme by minimizing or annulling the environmental impact and to attend a sustainable process development concept. PMID:20031309

Dettmer, Aline; Nunes, Keila Guerra Pacheco; Gutterres, Mariliz; Marcílio, Nilson Romeu

2010-04-15

256

Longitudinal analysis of inflammation and microbiota dynamics in a model of mild chronic dextran sulfate sodium-induced colitis in mice  

PubMed Central

AIM: To characterize longitudinally the inflammation and the gut microbiota dynamics in a mouse model of dextran sulfate sodium (DSS)-induced colitis. METHODS: In animal models, the most common method used to trigger colitis is based on the oral administration of the sulfated polysaccharides DSS. The murine DSS colitis model has been widely adopted to induce severe acute, chronic or semi-chronic colitis, and has been validated as an important model for the translation of mice data to human inflammatory bowel disease (IBD). However, it is now clear that models characterized by mild intestinal damage are more accurate for studying the effects of therapeutic agents. For this reason, we have developed a murine model of mild colitis to study longitudinally the inflammation and microbiota dynamics during the intestinal repair processes, and to obtain data suitable to support the recovery of gut microbiota-host homeostasis. RESULTS: All plasma cytokines evaluated, except IL-17, began to increase (P < 0.05), after 7 d of DSS administration. IL-17 only began to increase 4 d after DSS withdrawal. IL-1? and IL-17 continue to increase during the recovery phase, even when clinical signs of colitis had disappeared. IL-6, IL-10 and IFN-? reached their maxima 4 d after DSS withdrawal and decreased during the late recovery phase. TNF? reached a peak (a three- fold increase, P < 0.05), after which it slightly decreased, only to increase again close to the end of the recovery phase. DSS administration induced profound and rapid changes in the mice gut microbiota. After 3 d of DSS administration, we observed a major reduction in Bacteroidetes/Prevotella and a corresponding increase in Bacillaceae, with respect to control mice. In particular, Bacteroidetes/Prevotella decreased from a relative abundance of 59.42%-33.05%, while Bacillaceae showed a concomitant increase from 2.77% to 10.52%. Gut microbiota rapidly shifted toward a healthy profile during the recovery phase and returned normal 4 d after DSS withdrawal. Cyclooxygenase 2 expression started to increase 4 d after DSS withdrawal (P < 0.05), when dysbiosis had recovered, and continued to increase during the recovery phase. Taken together, these data indicated that a chronic phase of intestinal inflammation, characterized by the absence of dysbiosis, could be obtained in mice using a single DSS cycle. CONCLUSION: Dysbiosis contributes to the local and systemic inflammation that occurs in the DSS model of colitis; however, chronic bowel inflammation is maintained even after recovery from dysbiosis. PMID:24587679

De Fazio, Luigia; Cavazza, Elena; Spisni, Enzo; Strillacci, Antonio; Centanni, Manuela; Candela, Marco; Praticò, Chiara; Campieri, Massimo; Ricci, Chiara; Valerii, Maria Chiara

2014-01-01

257

Dextran sulfate sodium and 2,4,6-trinitrobenzene sulfonic acid induce lipid peroxidation by the proliferation of intestinal gram-negative bacteria in mice  

PubMed Central

Abstrect Background To understand whether TLR-4-linked NF-kB activation negatively correlates with lipid peroxidation in colitic animal models, we caused colitis by the treatment with dextran sulfate sodium (DSS) or 2,4,6-trinitrobenzenesulfonic acid (TNBS) to C3H/HeJ (TLR-4-defective) and C3H/HeN (wild type) mice, investigated inflammatory markers, lipid peroxidation, proinflammatory cytokines and TLR-4-linked NF-?B activation, in colon and intestinal bacterial composition in vivo. Methods Orally administered DSS and intrarectally injected TNBS all caused severe inflammation, manifested by shortened colons in both mice. These agents increased intestinal myeloperoxidase activity and the expression of the proinflammatory cytokines, IL-1?, TNF-? and IL-6, in the colon. Results DSS and TNBS induced the protein expression of TLR-4 and activated transcription factor NF-?B. However, these colitic agents did not express TLR-4 in C3H/HeJ mice. Of proinflammatory cytokines, IL-1? was most potently expressed in C3H/HeN mice. IL-1? potently induced NF-?B activation in CaCo-2 cells, but did not induce TLR-4 expression. DSS and TNBS increased lipid peroxide (malondialdehyde) and 4-hydroxy-2-nonenal content in the colon, but reduced glutathione content and superoxide dismutase and catalase activities. These colitic inducers increased the number of Enterobacteriaceae grown in DHL agar plates in both mice, although the number of anaerobes and bifidobacteria grown in GAM and BL agar plates was reduced. E. coli, K. pneumoniae and Proteus mirabilis isolated in DHL agar plates increased lipid peroxidation in liposomes prepared by L-?-phosphatidylcholine, but B. animalis and B. cholerium isolated from BL agar plates inhibited it. Discussion These findings suggest that DSS and TNBS may cause colitis by inducing lipid peroxidation and enterobacterial proliferation, which may deteriorate the colitis by regulating proinflammatory cytokines via TLR-4-linked NF-?B activation pathway. PMID:20181058

2010-01-01

258

Serum Amino Acids Profile and the Beneficial Effects of L-Arginine or L-Glutamine Supplementation in Dextran Sulfate Sodium Colitis  

PubMed Central

This study was conducted to investigate serum amino acids profile in dextran sulfate sodium (DSS)-induced colitis, and impacts of graded dose of arginine or glutamine supplementation on the colitis. Using DSS-induced colitis model, which is similar to human ulcerative colitis, we determined serum profile of amino acids at day 3, 7, 10 and 12 (5 days post DSS treatment). Meanwhile, effects of graded dose of arginine (0.4%, 0.8%, and 1.5%) or glutamine (0.5%, 1.0% and 2.0%) supplementation on clinical parameters, serum amino acids, colonic tight junction proteins, colonic anti-oxidative indicators [catalase, total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px)], colonic pro-inflammatory cytokines [interleukin-1 beta (IL-1?), IL-6, IL-17 and tumor necrosis factor alpha (TNF-?)] in DSS-induced colitis were fully analyzed at day 7 and 12. Additionally, the activation of signal transduction pathways, including nuclear factor kappa B (NF-?B), mitogen-activated protein kinases (MAPK), phosphoinositide-3-kinases (PI3K)/PI3K-protein kinase B (Akt), and myosin light chain kinase (MLCK)- myosin light chain (MLC20), were analyzed using immunoblotting. Serum amino acids analysis showed that DSS treatment changed the serum contents of amino acids, such as Trp, Glu, and Gln (P<0.05). Dietary arginine or glutamine supplementation had significant (P<0.05) influence on the clinical and biochemical parameters (T-SOD, IL-17 and TNF-?) in colitis model. These results were associated with colonic NF-?B, PI3K-Akt and MLCK signaling pathways. In conclusion, arginine or glutamine could be a potential therapy for intestinal inflammatory diseases. PMID:24505477

Wu, Miaomiao; Liu, Gang; Yang, Guan; Xion, Yan; Su, Dingding; Wu, Li; Li, Tiejun; Chen, Shuai; Duan, Jielin; Yin, Yulong; Wu, Guoyao

2014-01-01

259

The Noncommensal Bacterium Methylococcus capsulatus (Bath) Ameliorates Dextran Sulfate (Sodium Salt)-Induced Ulcerative Colitis by Influencing Mechanisms Essential for Maintenance of the Colonic Barrier Function  

PubMed Central

Dietary inclusion of a bacterial meal has recently been shown to efficiently abolish soybean meal-induced enteritis in Atlantic salmon. The objective of this study was to investigate whether inclusion of this bacterial meal in the diet could abrogate disease development in a murine model of epithelial injury and colitis and thus possibly have therapeutic potential in human inflammatory bowel disease. C57BL/6N mice were fed ad libitum a control diet or an experimental diet containing 254 g/kg of body weight BioProtein, a bacterial meal consisting of Methylococcus capsulatus (Bath), together with the heterogenic bacteria Ralstonia sp., Brevibacillus agri, and Aneurinibacillus sp. At day 8, colitis was induced by 3.5% dextran sulfate sodium (DSS) ad libitum in the drinking water for 6 days. Symptoms of DSS treatment were less profound after prophylactic treatment with the diet containing the BioProtein. Colitis-associated parameters such as reduced body weight, colon shortening, and epithelial damage also showed significant improvement. Levels of acute-phase reactants, proteins whose plasma concentrations increase in response to inflammation, and neutrophil infiltration were reduced. On the other, increased epithelial cell proliferation and enhanced mucin 2 (Muc2) transcription indicated improved integrity of the colonic epithelial layer. BioProtein mainly consists of Methylococcus capsulatus (Bath) (88%). The results that we obtained when using a bacterial meal consisting of M. capsulatus (Bath) were similar to those obtained when using BioProtein in the DSS model. Our results show that a bacterial meal of the noncommensal bacterium M. capsulatus (Bath) has the potential to attenuate DSS-induced colitis in mice by enhancing colonic barrier function, as judged by increased epithelial proliferation and increased Muc2 transcription. PMID:23064342

Hult, Lene T. Olsen; Spetalen, Signe; Kaldhusdal, Magne; Christofferesen, Trine Eker; Bengtsson, Oskar; Romarheim, Odd Helge; Jacobsen, Morten; Lea, Tor

2013-01-01

260

The noncommensal bacterium Methylococcus capsulatus (Bath) ameliorates dextran sulfate (Sodium Salt)-Induced Ulcerative Colitis by influencing mechanisms essential for maintenance of the colonic barrier function.  

PubMed

Dietary inclusion of a bacterial meal has recently been shown to efficiently abolish soybean meal-induced enteritis in Atlantic salmon. The objective of this study was to investigate whether inclusion of this bacterial meal in the diet could abrogate disease development in a murine model of epithelial injury and colitis and thus possibly have therapeutic potential in human inflammatory bowel disease. C57BL/6N mice were fed ad libitum a control diet or an experimental diet containing 254 g/kg of body weight BioProtein, a bacterial meal consisting of Methylococcus capsulatus (Bath), together with the heterogenic bacteria Ralstonia sp., Brevibacillus agri, and Aneurinibacillus sp. At day 8, colitis was induced by 3.5% dextran sulfate sodium (DSS) ad libitum in the drinking water for 6 days. Symptoms of DSS treatment were less profound after prophylactic treatment with the diet containing the BioProtein. Colitis-associated parameters such as reduced body weight, colon shortening, and epithelial damage also showed significant improvement. Levels of acute-phase reactants, proteins whose plasma concentrations increase in response to inflammation, and neutrophil infiltration were reduced. On the other, increased epithelial cell proliferation and enhanced mucin 2 (Muc2) transcription indicated improved integrity of the colonic epithelial layer. BioProtein mainly consists of Methylococcus capsulatus (Bath) (88%). The results that we obtained when using a bacterial meal consisting of M. capsulatus (Bath) were similar to those obtained when using BioProtein in the DSS model. Our results show that a bacterial meal of the noncommensal bacterium M. capsulatus (Bath) has the potential to attenuate DSS-induced colitis in mice by enhancing colonic barrier function, as judged by increased epithelial proliferation and increased Muc2 transcription. PMID:23064342

Kleiveland, Charlotte R; Hult, Lene T Olsen; Spetalen, Signe; Kaldhusdal, Magne; Christofferesen, Trine Eker; Bengtsson, Oskar; Romarheim, Odd Helge; Jacobsen, Morten; Lea, Tor

2013-01-01

261

Serum amino acids profile and the beneficial effects of L-arginine or L-glutamine supplementation in dextran sulfate sodium colitis.  

PubMed

This study was conducted to investigate serum amino acids profile in dextran sulfate sodium (DSS)-induced colitis, and impacts of graded dose of arginine or glutamine supplementation on the colitis. Using DSS-induced colitis model, which is similar to human ulcerative colitis, we determined serum profile of amino acids at day 3, 7, 10 and 12 (5 days post DSS treatment). Meanwhile, effects of graded dose of arginine (0.4%, 0.8%, and 1.5%) or glutamine (0.5%, 1.0% and 2.0%) supplementation on clinical parameters, serum amino acids, colonic tight junction proteins, colonic anti-oxidative indicators [catalase, total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px)], colonic pro-inflammatory cytokines [interleukin-1 beta (IL-1?), IL-6, IL-17 and tumor necrosis factor alpha (TNF-?)] in DSS-induced colitis were fully analyzed at day 7 and 12. Additionally, the activation of signal transduction pathways, including nuclear factor kappa B (NF-?B), mitogen-activated protein kinases (MAPK), phosphoinositide-3-kinases (PI3K)/PI3K-protein kinase B (Akt), and myosin light chain kinase (MLCK)-myosin light chain (MLC20), were analyzed using immunoblotting. Serum amino acids analysis showed that DSS treatment changed the serum contents of amino acids, such as Trp, Glu, and Gln (P<0.05). Dietary arginine or glutamine supplementation had significant (P<0.05) influence on the clinical and biochemical parameters (T-SOD, IL-17 and TNF-?) in colitis model. These results were associated with colonic NF-?B, PI3K-Akt and MLCK signaling pathways. In conclusion, arginine or glutamine could be a potential therapy for intestinal inflammatory diseases. PMID:24505477

Ren, Wenkai; Yin, Jie; Wu, Miaomiao; Liu, Gang; Yang, Guan; Xion, Yan; Su, Dingding; Wu, Li; Li, Tiejun; Chen, Shuai; Duan, Jielin; Yin, Yulong; Wu, Guoyao

2014-01-01

262

The Influence of Fluorocarbon and Hydrocarbon Acyl Groups at the Surface of Bovine Carbonic Anhydrase II on the Kinetics of Denaturation by Sodium Dodecyl Sulfate  

PubMed Central

This paper examines the influence of acylation of the Lys-?-NH3+ groups of bovine carbonic anhydrase (BCA, E.C. 4.2.1.1) to Lys-?-NHCOR (R = -CH3, -CH2CH3, and -CH(CH3)2, -CF3) on the rate of denaturation of this protein in buffer containing sodium dodecyl sulfate (SDS). Analysis of the rates suggested separate effects due to electrostatic charge and hydrophobic interactions. Rates of denaturation (kAc,n) of each series of acylated derivatives depended on the number of acylations (n). Plots of log kAc,n vs. n followed U-shaped curves. Within each series of derivatives, rates of denaturation decreased as n increased to ~7; this decrease was compatible with increasingly unfavorable electrostatic interactions between SDS and protein. In this range of n, rates of denaturation also depended on the choice of the acyl group as n increased to ~7, in a manner compatible with favorable hydrophobic interactions between SDS and the -NHCOR groups. As n increased in the range 7 < n < 14 however, rates of denaturation stayed approximately constant; analysis suggested these rates were compatible with an increasingly important contribution to denaturation that depended both on the net negative charge of the protein and on the hydrophobicity of the R group. The mechanism of denaturation thus seems to change with the extent of acylation of the protein. For derivatives with the same net electrostatic charge, rates of denaturation increased with the acyl group (by a factor of ~3 for n ~ 14) in the order CH3CONH- < CH3CH2CONH- < (CH3)2CHCONH- < CF3CONH-. These results suggested that the hydrophobicity of CF3CONH- is slightly greater (by a factor of < 2) than that of RHCONH- similar in surface area. PMID:21182314

Lee, Andrew; Mirica, Katherine A.; Whitesides, George M.

2011-01-01

263

Deletion of Intestinal Epithelial Cell STAT3 Promotes T Lymphocyte STAT3 Activation and Chronic Colitis Following Acute Dextran Sodium Sulfate Injury in Mice  

PubMed Central

BACKGROUND Intestinal epithelial cell (IEC) Stat3 is required for wound healing following acute Dextran Sodium Sulfate (DSS) injury. We hypothesized that loss of IEC STAT3 would promote the development of chronic colitis following acute DSS injury. METHODS Colitis was induced in IEC-specific Stat3 deficient mice (Stat3?IEC) and littermate controls (Stat3Flx/Flx) with 4%DSS for 7 days, followed by water consumption for 21 days. Epithelial and immune mediators and severity of colitis were determined. RESULTS Survival, colon length, and histologic injury were significantly worse at day 28 in Stat3?IEC mice. IEC proliferation and apoptosis did not vary by genotype at day 14 or day 28. The colonic lamina propria frequency of pSTAT3+ cells was increased at day 28 and correlated with histologic injury in Stat3?IEC mice. The frequency of colonic F480+pSTAT3+ macrophages and CD3+pSTAT3+ T-lymphocytes were increased in Stat3?IEC mice as compared to Stat3Flx/Flx controls. In Stat3?IEC mice, colonic expression of Stat3 target genes Reg3? and Reg3? which mediate epithelial restitution were significantly decreased, while expression of IL-17a, IFN?, CXCL2, CXCL10, and CCL2 were significantly increased and correlated with the increase in histologic severity at Day 28(p<.05). IL-17a expression also correlated with the increased lamina propria frequency of CD3+pSTAT3+ T-lymphocytes. CONCLUSIONS Loss of intestinal epithelial Stat3 leads to more severe chronic inflammation following acute injury which is not accounted for by a sustained defect in epithelial proliferation or apoptosis 7 or 21 days after one cycle of DSS but rather defective REG3 expression and expansion of pSTAT3+ lymphocytes and IL-17a expression. PMID:23429443

Willson, Tara A.; Jurickova, Ingrid; Collins, Margaret; Denson, Lee A.

2015-01-01

264

Effects of dietary glutamine on the homeostasis of CD4+ T cells in mice with dextran sulfate sodium-induced acute colitis.  

PubMed

This study investigated the effects of dietary glutamine (Gln) on T-helper (Th) and T regulatory (Treg) cell homeostasis and colonic inflammatory mediator expression in mice with dextran sulfate sodium (DSS)-induced colitis. Mice were randomly assigned to 4 groups with 2 normal control (C and G) and 2 DSS-treated groups (DC and DG). The C and DC groups were fed a common semipurified diet, while the G and DG groups received an identical diet except that part of the casein was replaced by Gln, which provided 25% of the total amino acid nitrogen. Mice were fed the diets for 10 days. On day 6, mice in the normal control groups were given distilled water, while those in the DSS groups were given distilled water containing 1.5% DSS for 5 d. At the end of the experiment, the mice were sacrificed for further examination. Results showed that DC group had higher plasma haptoglobin, colonic weight, immunoglobulin G, inflammatory cytokine and nuclear factor (NF)-?B protein levels. Gln administration lowered inflammatory mediators and NF-?B/I?B? ratio in colitis. Compared with the DC group, the percentages of interleukin-17F and interferon-? in blood and transcription factors, T-bet and RAR-related orphan receptor-?t, gene expressions in mesenteric lymph nodes were lower, whereas blood Foxp3 was higher in the DG group. Also, DG group had lower colon injury score. These results suggest that Gln administration suppressed Th1/Th17 and Th-associated cytokine expressions and upregulated the expression of Tregs, which may modulate the balance of Th/Treg and reduce inflammatory reactions in DSS-induced colitis. PMID:24416230

Hsiung, Yuan-Chin; Liu, Jun-Jen; Hou, Yu-Chen; Yeh, Chiu-Li; Yeh, Sung-Ling

2014-01-01

265

Inhibitory effects of meju prepared with mixed starter cultures on azoxymethane and dextran sulfate sodium-induced colon carcinogenesis in mice  

PubMed Central

Backgrounds: Meju is the main ingredient and the starter culture of traditional Korean fermented soybean foods; these fermented soybean products are well-known for their various health benefits, including anticancer effects. We developed the grain-type meju using probiotic mixed starter cultures to improve the qualities and functionalities of fermented soybean products, as well as the meju itself. In this study, the inhibitory effects of the grain-type meju were investigated in azoxymethane (AOM) and dextran sulfate sodium (DSS)-induced colon carcinogenesis mice model. Materials and Methods: AOM and DSS colon carcinogenesis was induced in female C57BL/6 mice and meju was orally administered for 4 weeks. The body weight, colon length, and colon weight of mice were determined, and colonic tissues were histologically observed. The serum levels of proinflammatory cytokines and the levels of inflammation- and apoptosis-related genes in colonic tissue were also analyzed. Results: The administration of meju using probiotic mixed starter cultures ameliorated the symptoms of colon cancer and reduced number of neoplasia, and reduced serum proinflammatory cytokine levels and iNOS and COX-2 expression levels in colonic tissue. It increased Bax and reduced Bcl-2 expression levels and increased p21 and p53 expression in colonic tissues. Conclusion: The meju showed inhibitory effects on the progression of colon cancer induced by AOM and DSS by ameliorating the symptoms of colon cancer, reducing the number of neoplasias and regulating proinflammatory cytokine levels and the expressions of inflammation- and apoptosis-related genes in the colonic tissue. PMID:23230391

Jeong, Ji-Kang; Chang, Hee-Kyung; Park, Kun-Young

2012-01-01

266

Experimental studies on the influence of surfactants on intestinal absorption of drugs. Cefadroxil as model drug and sodium lauryl sulfate as model surfactant: studies in rat duodenum.  

PubMed

The effect of sodium lauryl sulfate (CAS 151-21-3) on the duodenal absorption of cefadroxil (CAS 50370-12-2) has been investigated with the aid of a classical rat gut in situ preparation. Both compounds were entirely compatible in working solutions. Cefadroxil was found to be very stable and only slightly solubilized in the micellar phase. The apparent first-order absorption rate constants for the free antibiotic fraction were determined in free solution, and in the presence of variable surfactant concentration in luminal fluid. A functional interpretation of these data, based both on the law of mass action and the complete noncompetitive transport inhibition equations, showed that the surfactant acts as a nonspecific inhibitor of the carrier-mediated absorption of the antibiotic, but also as an enhancer of its passive absorption component. The net result was an outstanding reduction in the absorption capacity of cefadroxil when it was perfused at 0.1 mg/ml, i.e. far from its carrier saturation (from 3.0 h-1 in free solution to 2.0(-1) at high surfactant concentration, with a minimum of about 1.4 h-1 in the presence of the surfactant at 0.5 mg/mg in duodenal fluid). When cefadroxil was perfused at 10.0 mg/ml, i.e. with its carrier-mediated transport beyond the saturation, the net result was a progressively enhanced absorption (ranging from about 0.9 h-1 in free solution to 2.0 h-1 at high surfactant concentration).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7488302

Sancho-Chust, V; Bengochea, M; Fabra-Campos, S; Casabó, V G; Martínez-Cámara, M J; Martín-Villodre, A

1995-09-01

267

Reductions of Salmonella enterica on chicken breast by thymol, acetic acid, sodium dodecyl sulfate or hydrogen peroxide combinations as compared to chlorine wash.  

PubMed

Poultry products are important vehicles for Salmonella transmission to humans and have been incriminated in several Salmonella outbreaks. Thymol (THY) from thyme oil has wide inhibitory effects against foodborne pathogens including Salmonella, and has shown great potential as a natural alternative to chlorine. In order to improve the cost-effectiveness of thymol-based washing solutions, formulas of THY with combination of organic acid or surfactant were developed and their efficacies to reduce Salmonella on chicken breast were investigated in the current study. Surface-inoculated chicken breasts were washed with the two thymol-based washing solutions: 0.2 mg/mL THY+5% (w/v) sodium dodecyl sulfate (SDS)+2 mg/mL acetic acid (AA) or 0.2 mg/mL THY+2 mg/mL AA for 2 min. Both solutions achieved around 2.2 log reductions of Salmonella on chicken breast and their efficacy was comparable to log reduction obtained by 200 ppm chlorine washing. Addition of SDS did not result in more log reduction of Salmonella on chicken meat samples. More than 3.3 log reduction in the used THY washing solutions was determined and it was similar to log reduction from the spent chlorine solution. None of these antimicrobial agents changed the pH and texture values of chicken breasts. Therefore, 0.2 mg/mL THY+2 mg/mL AA has great potential to be a natural alternative to chlorine-based washing solution for reducing Salmonella contamination on chicken breast meat. PMID:22030209

Lu, Y; Wu, C

2012-01-01

268

Self-aggregation of synthesized novel bolaforms and their mixtures with sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB) in aqueous medium.  

PubMed

Bolaforms B(1), B(2), and B(3) of the formulas, Br(-)Me(3)N(+)(CH(2))(10)N(+)Me(3)Br(-), Br(-)Me(3)N(+)(CH(2))(10)OH, and Br(-)Me(3)N(+)(CH(2))(10)COO(-)Na(+), respectively, were synthesized, and their properties in the bulk as well as at the air/aqueous NaBr (10 mM) solution interface have been studied. Their interactions with sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB) also have been investigated. Tensiometry, conductometry, spectrophotometry, and microcalorimetry techniques were used for characterization and estimation. Both pure bolaforms and their mixtures with SDS and CTAB have been found to self-aggregate, forming micelles in solution. The mixed systems of bolaform and SDS have been observed to form both micelles and vesicles. Their mutual interactions were synergistic, which at the interface was more spontaneous than in the bulk. The interfacial and bulk compositions of the mixed binary systems (bolaform and SDS or CTAB) with their associated interaction parameters have been estimated from the Rosen interaction model and the regular solution theory of Rubingh, respectively. The formed vesicles have been found to entrap the water-soluble dye, bromophenol blue, and the dye solubilized vesicles of B(1)-SDS and B(2)-SDS completely eluted out of the sephadex column proving their formation. A rough estimation of the size and polydispersity index of the formed micelles and vesicles has been made from DLS measurements. PMID:20476731

Maiti, Kajari; Mitra, Debolina; Mitra, Rajendra N; Panda, Amiya K; Das, Prasanta K; Rakshit, Animesh K; Moulik, Satya P

2010-06-10

269

Dextran sodium sulfate inhibits the activities of both polymerase and reverse transcriptase: lithium chloride purification, a rapid and efficient technique to purify RNA  

PubMed Central

Background Dextran sodium sulfate (DSS) is commonly used in mouse studies to induce a very reproducible colitis that effectively mimics the clinical and histological features of human inflammatory bowel disease (IBD) patients, especially ulcerative colitis. However, the mechanisms of action of DSS remain poorly understood, and observations by our laboratory and other groups indicate that DSS contamination of colonic tissues from DSS-treated mice potently inhibits the quantitative reverse-transcription polymerase chain reaction (qRT-PCR) amplification of mRNA. Results A prior study used poly-A-mediated mRNA purification to remove DSS from RNA extracts, but we herein report a second efficient and cost-effective approach to counteract this inhibition, using lithium chloride precipitation to entirely remove DSS from RNAs. We also explored how DSS interferes with qRT-PCR process, and we report for the first time that DSS can alter the binding of reverse transcriptase to previously primed RNA and specifically inhibits the enzymatic activities of reverse transcriptase and Taq polymerase in vitro. This likely explains why DSS-treated colonic RNA is not suitable to qRT-PCR amplification without a previous purification step. Conclusion In summary, we provide a simple method to remove DSS from colonic RNAs, and we demonstrate for the first time that DSS can inhibit the activities of both polymerase and reverse transcriptase. In order to reliably analyze gene expression in the colonic mucosa of DSS-treated mice, the efficiency rate of qRT-PCR must be the same between all the different experimental groups, including the water-treated control group, suggesting that whatever the duration and the percentage of the DSS treatment, RNAs must be purified. PMID:24010775

2013-01-01

270

Chromatographic analysis of phenethylamine-antihistamine combinations using C8, C18 or cyano columns and micellar sodium dodecyl sulfate-pentanol mixtures.  

PubMed

The chromatographic behaviour of binary and ternary mixtures of several phenethylamines (phenylephrine, phenylpropanolamine, ephedrine, pseudoephedrine and methoxyphenamine) and antihistamines (pheniramine, carbinoxamine, doxylamine, chlorpheniramine, dexchlorpheniramine, dexbrompheniramine, diphenhydramine, tripolidine, azatadine and phenyltoloxamine), found in cough-cold pharmaceutical preparations, was studied using C8, C18 and cyano columns, micellar mobile phases of sodium dodecyl sulfate (SDS) and pentanol and UV detection. Using a C8 column and mobile phases of 0.05 mol l-1 SDS-6% v/v pentanol or 0.15 mol l-1 SDS-2% v/v pentanol at pH 7, more than 30 different phenethylamine-antihistamine combinations can be resolved in < 15 min. Intra- and inter-day repeatabilities and reproducibilities evaluated at three different drug concentrations (0.5, 5 and 25 micrograms ml-1, n = 10) were below 1.6, 2.5 and 2.4%, respectively. The drug amounts found in 18 formulations agreed with those declared by the manufacturers within the tolerance limits, and with those obtained using a mobile phase of 55% v/v methanol at pH 7. No interference was observed from other accompanying drugs such as acetylsalicylic acid, ascorbic acid, betamethasone, bromhexine, caffeine, codeine, dextromethorphan, paracetamol, prednisolone, salicylamide and tartrazine. The proposed procedure has the advantage over the conventional aqueous-organic procedure of using a small amount of organic solvent, which is highly retained in the SDS solution. The efficiencies are also greater. On the other hand, in the micellar system, the retentions of phenethylamines and antihistamines are similar, although the compounds can be easily resolved. In contrast, using the methanol-water mobile phase, the phenethylamines are weakly retained, whereas the antihistamines usually show a high retention. PMID:11340978

Gil-Agustí, M; Capella-Peiró, E; Monferrer-Pons, L; García-Alvarez-Coque, M C; Esteve-Romero, J

2001-04-01

271

Inactivation of Salmonella and Escherichia coli O157:H7 on lettuce and poultry skin by combinations of levulinic acid and sodium dodecyl sulfate.  

PubMed

Four organic acids (lactic acid, acetic acid, caprylic acid, and levulinic acid) and sodium dodecyl sulfate (SDS) were evaluated individually or in combination for their ability to inactivate Salmonella and Escherichia coli O157:H7. Results from pure culture assays in water with the treatment chemical revealed that 0.5% organic acid and 0.05 to 1% SDS, when used individually, reduced pathogen cell numbers by < or = 2 log CFU/ml within 20 min at 21 degrees C. The combination of any of these organic acids at 0.5% with 0.05% SDS resulted in > 7 log CFU/ml inactivation of Salmonella and E. coli O157:H7 within 10 s at 21 degrees C. A combination of levulinic acid and SDS was evaluated at different concentrations for pathogen reduction on lettuce at 21 degrees C, on poultry (wings and skin) at 8 degrees C, and in water containing chicken feces or feathers at 21 degrees C. Results revealed that treatment of lettuce with a combination of 3% levulinic acid plus 1% SDS for < 20 s reduced both Salmonella and E. coli O157:H7 populations by > 6.7 log CFU/g on lettuce. Salmonella and aerobic bacterial populations on chicken wings were reduced by > 5 log CFU/g by treatment with 3% levulinic acid plus 2% SDS for 1 min. Treating water heavily contaminated with chicken feces with 3% levulinic acid plus 2% SDS reduced Salmonella populations by > 7 log CFU/ml within 20 s. The use of levulinic acid plus SDS as a wash solution may have practical application for killing foodborne enteric pathogens on fresh produce and uncooked poultry. PMID:19517717

Zhao, Tong; Zhao, Ping; Doyle, Michael P

2009-05-01

272

Dextran sulfate sodium administered orally is depolymerized in the stomach and induces cell cycle arrest plus apoptosis in the colon in early mouse colitis.  

PubMed

The mechanisms responsible for human inflammatory bowel disease remain poorly understood. The pathogenic factors for dextran sulfate sodium (DSS)-induced colitis, one of the experimental animal colitis models, also remain unknown. Furthermore, detailed studies on DSS metabolism in the gut lumen have not been reported. Therefore, we investigated DSS metabolism in the mouse gut lumen and report the mechanisms which induce colitis. DSS was labeled with 2-aminopyridine (pyridylamino-DSS, PA-DSS). PA-DSS was administered orally to male BALB/cA Jcl mice. The metabolites and histological findings were observed using HPLC and light or fluorescence microscopy. PA-DSS with Mr 5000 was depolymerized rapidly in the gastric lumen, and the depolymerized PA-DSS was absorbed in the small intestine. Therefore, the majority of the PA-DSS in the cecal contents returned to Mr 5000 PA-DSS, escaping absorption in the small intestine. Mr 5000 DSS induced severe colitis, and immunostaining using an anti-mouse Ki-67 antibody and the TUNEL assay showed that DSS arrested the cell cycle at the G0 phase and induced apoptosis of the colonic epithelium. Mr 2500 PA-DSS, however, induced these same effects weakly. During these processes, we observed that the epithelial cells can depolymerize DSS themselves. An in vitro study using Caco-2 cells also showed similar effects. Mr 5000 DSS was depolymerized in the gut lumen and epithelial cells. Therefore, the molecular mass distribution of the DSS differed between each part in the lumen. As an early stage event, DSS induced colitis through cell cycle arrest and apoptosis according to its molecular mass. PMID:22895560

Araki, Yoshio; Bamba, Tadao; Mukaisho, Ken-ichi; Kanauchi, Osamu; Ban, Hiromitsu; Bamba, Shigeki; Andoh, Akira; Fujiyama, Yoshihide; Hattori, Takanori; Sugihara, Hiroyuki

2012-11-01

273

Genetic Deletion of Klf4 in the Mouse Intestinal Epithelium Ameliorates Dextran Sodium Sulfate–induced Colitis by Modulating the NF-?B Pathway Inflammatory Response  

PubMed Central

Background Krüppel-like factor 4 (KLF4) is a zinc finger transcription factor expressed in the differentiated epithelial cells lining of the intestine. Under physiological conditions, KLF4 inhibits cell proliferation. Conversely, KLF4 mediates proinflammatory signaling in macrophages and its overexpression in the esophageal epithelium activates cytokines, leading to inflammation-mediated esophageal squamous cell cancer formation in mice. Here, we tested whether KLF4 has a proinflammatory activity in experimental colitis in mice. Methods Villin-Cre;Klf4fl/fl mice with intestine-specific Klf4 deletion (Klf4?IS) and control mice with floxed Klf4 gene (Klf4fl/fl) were treated or not with 3% dextran sodium sulfate (DSS) for 7 days to induce colitis. Additionally, WT mice were administered or not, nanoparticles loaded with scrambled or Klf4-siRNA, and concomitantly given DSS. Results Compared with DSS-treated Klf4fl/fl mice, DSS-treated Klf4?IS mice were significantly less sensitive to DSS-induced colitis. DSS treatment of Klf4fl/fl mice induced Klf4 expression in the crypt zone of the colonic epithelium. DSS-treated Klf4?IS mice had increased proliferation relative to DSS-treated control mice. DSS treatment induced NF-?B signaling pathway in Klf4fl/fl mice colon but not Klf4?IS mice. Additionally, WT mice given DSS and nanoparticle/Klf4-siRNA were less sensitive to colitis and had reduced Klf4 expression and while maintaining the proliferative response in the colonic epithelium. Conclusions Our results indicate that Klf4 is an important mediator of DSS-induced colonic inflammation by modulating NF-?B signaling pathway and could be involved in the pathogenesis and/or propagation of inflammatory bowel disease. Thus, Klf4 may represent a novel therapeutic target in inflammatory bowel disease. PMID:24681655

Ghaleb, Amr M.; Laroui, Hamed; Merlin, Didier; Yang, Vincent W.

2014-01-01

274

Arctigenin but not arctiin acts as the major effective constituent of Arctium lappa L. fruit for attenuating colonic inflammatory response induced by dextran sulfate sodium in mice.  

PubMed

The crude powder of the fruit of Arctium lappa L. (ALF) has previously been reported to attenuate experimental colitis in mice. But, its main effective ingredient and underlying mechanisms remain to be identified. In this study, ALF was extracted with ethanol, and then successively fractionated into petroleum ether, ethyl acetate, n-butanol and water fraction. Experimental colitis was induced by dextran sulfate sodium (DSS) in mice. Among the four fractions of ALF, the ethyl acetate fraction showed the most significant inhibition of DSS-induced colitis in mice. The comparative studies of arctigenin and arctiin (the two main ingredients of ethyl acetate fraction) indicated that arctigenin rather than arctiin could reduce the loss of body weight, disease activity index and histological damage in the colon. Arctigenin markedly recovered the loss of intestinal epithelial cells (E-cadherin-positive cells) and decreased the infiltration of neutrophils (MPO-positive cells) and macrophages (CD68-positive cells). Arctigenin could down-regulate the expressions of TNF-?, IL-6, MIP-2, MCP-1, MAdCAM-1, ICAM-1 and VCAM-1 at both protein and mRNA levels in colonic tissues. Also, it markedly decreased the MDA level, but increased SOD activity and the GSH level. Of note, the efficacy of arctigenin was comparable or even superior to that of the positive control mesalazine. Moreover, it significantly suppressed the phosphorylation of MAPKs and the activation of NF-?B, including phosphorylation of I?B? and p65, p65 translocation and DNA binding activity. In conclusion, arctigenin but not arctiin is the main active ingredient of ALF for attenuating colitis via down-regulating the activation of MAPK and NF-?B pathways. PMID:25284342

Wu, Xin; Yang, Yan; Dou, Yannong; Ye, Jun; Bian, Difei; Wei, Zhifeng; Tong, Bei; Kong, Lingyi; Xia, Yufeng; Dai, Yue

2014-12-01

275

Macrokinetics of magnesium sulfite oxidation inhibited by ascorbic acid.  

PubMed

Magnesia flue gas desulfurization is a promising process for small to medium scale industrial coal-fired boilers in order to reduce sulfur dioxide emissions, in which oxidation control of magnesium sulfite is of great importance for the recycling of products. Effects of four inhibitors were compared by kinetic experiments indicating that ascorbic acid is the best additive, which retards the oxidation process of magnesium sulfite in trace presence. The macrokinetics of magnesium sulfite oxidation inhibited by ascorbic acid were studied. Effects of the factors, including ascorbic acid concentration, magnesium sulfite concentration, oxygen partial pressure, pH, and temperature, were investigated in a stirred reactor with bubbling. The results show that the reaction rate is -0.55 order in ascorbic acid, 0.77 in oxygen partial pressure, and zero in magnesium sulfite concentration, respectively. The apparent activation energy is 88.0 kJ mol(-1). Integrated with the kinetic model, it is concluded that the oxidation rate of magnesium sulfite inhibited by ascorbic acid is controlled by the intrinsic chemical reaction. The result provides a useful reference for sulfite recovery in magnesia desulfurization. PMID:23692683

Lidong, Wang; Yongliang, Ma; Wendi, Zhang; Qiangwei, Li; Yi, Zhao; Zhanchao, Zhang

2013-08-15

276

Novel process of simultaneous removal of SO2 and NO2 by sodium humate solution.  

PubMed

A novel simultaneous flue gas desulfurization and denitrification (FGDD) process using sodium humate (HA-Na) solution was proposed. This study relates to the SO2/NO2 absorption efficiency and products of simultaneous removing SO2 and NO2 in a bubbling reactor, especially the effect of recycled water on the SO2/NO2 absorption. Under alkaline conditions, the sulfate content in S-containing compound decreases with the increase of NO2 concentration, whereas there is a contrary result under acidic conditions. Whether the absorption liquid is alkaline or acidic, the presence of NO2 improves the SO2 absorption into HA-Na solution, because NO2 may promote the oxidation of sulfite to sulfate. It seems that the presence of SO2 is unfavorable for the NO2 absorption, but the NO2 absorption efficiency can be improved with the cycle number rising due to the increasing amount of sulfite. Although all the ion concentrations of Na+,SO4(2-),SO3(2-), and NO3- have a gradual increase as the cycle number rises, the ion concentrations of SO4(2-) and Na+ are far more than that of the other ions, which results in a slight decrease of the SO2 absorption efficiency. However, the initial pH of HA-Na solution prepared by recycled water decreases from 10 to 8.1 with the cycle number increasing from 1 to 10, whereas the final pH (the pH after absorption reaction is finished) remains almost constant (3.3). The SO2 absorption efficiency is above 98% and the NO2 absorption efficiency may reach above 95% in the optimal condition in this process. The chief byproduct is a compound fertilizer consisting of humic acid (HA), sulfate, and nitrate. PMID:20704283

Hu, Guoxin; Sun, Zhiguo; Gao, Hanyang

2010-09-01

277

Analysis of commercial proanthocyanidins. Part 2: An electrospray mass spectrometry investigation into the chemical composition of sulfited quebracho (Schinopsis lorentzii and Schinopsis balansae) heartwood extract.  

PubMed

Proanthocyanidins (PACs) are natural plant-derived polymers used in leather tanning, wood adhesives, water purification, and mud additives for oil drilling. Quebracho (Schinopsis lorentzii and Schinopsis balansae) heartwood and mimosa (Acacia mearnsii) bark extracts are the major industrial sources of PACs. These commercial extracts are often sulfited via treatment with sodium hydrogen sulfite to reduce their viscosity and increase their solubility in water. An ESI-MS investigation into the molecular composition of sulfited (cold-water-soluble) quebracho heartwood extract indicates that sulfitation of the PACs occurs via S(N)2 attack of a sulfite ion at both C-2 and C-4 of the constituent flavan-3-ol monomer extender units. Attack at C-2 leads to the opening of the pyran ring. This releases an additional electron-donating phenolic hydroxy group on the A-ring and renders the extract more nucleophilic and suitable for the manufacturing of adhesives. Attack at C-4 leads to interflavanyl bond fission and decrease of the PAC oligomer chain length. The introduction of sulfonic acid moieties at C-2 or C-4 increases the polarity and water solubility of the hot water soluble (unsulfited) extract and transforms it into a cold-water-soluble extract. PMID:22513010

Venter, Pieter B; Senekal, Nadine D; Amra-Jordaan, Maryam; Bonnet, Susan L; Van der Westhuizen, Jan H

2012-06-01

278

Effects of the methyltrimethoxysilane coupling agent on phenolic and miscanthus composites containing calcium sulfite scrubber material  

NASA Astrophysics Data System (ADS)

The purpose of this research is to test the effects of methyltrimethoxysilane coupling agent on composite material containing calcium sulfite obtained from the Southern Illinois Power Co-operative. This scrubber material and the miscanthus plant are of interest due to their use in coal burning power plants to reduce toxic emission. When calcium sulfate is passed through coal fire gas emissions it absorbs mercury and sulfur. In these composites it is used as filler to reduce cost. Miscanthus is a source of both cellulose reinforcement and some natural resin. This plant has low care requirements, little mineral content, useful energy return, and positive environmental effects. Under investigation is whether a post-cure procedure or a silane coupling agent will positively impact the composite. Hot pressing alone may not be enough to fully cure the phenolic. It is hoped that the silane will increase the strength characteristics of the composite by enhancing adhesion between the calcium sulfite and phenolic resin. Possible effects on the miscanthus by the silane will also be tested. Phenolic is being utilized because of its recycling and biodegradable properties along with cost effectiveness in mass production. Composite mechanical performance was measured through 3-point bending to measure flexural strength and strain at breakage. A dynamic mechanical analyzer (DMA) was used to find thermomechanical properties. The post-cure was found to be effective, particularly on the final composite containing silane. When methyltrimethoxysilane was added to the miscanthus prior to fabrication, it was found to reduce flexural strength and density. However the addition of methyltrimethoxysilane to the calcium sulfite altered thermo-mechanical properties to a state more like pure phenolic, with added flexibility and thermal stability.

Jones, Sean

279

Baicalin down regulates the expression of TLR4 and NFkB-p65 in colon tissue in mice with colitis induced by dextran sulfate sodium  

PubMed Central

Background: Baicalin is one of flavonoid extracts from Scutellaria baicalensis, which has several functions including anti-inflammation, anti-bacteria, antitumor and et al. However, the mechanisms of anti-inflammatory of baicalin in ulcerative colitis is not clear. Methods: Mice colitis models were established by dextran sodium sulfate, Mice administrated with baicalin (100 mg/kg) and mesalazine (100 mg/kg) twice daily by intragastric injection for 7 days after colitis induced were defined as treated group. Then the mice were sacrificed and the colon samples were collected. Toll-like receptor-2, 4, 9 were detected by immunohistochemistry. Signaling proteins such as TLR4, MyD88, and NF-?B p65 were analyzed by western blotting. Cytokine’s mRNA include TNF-?, IL-6 IL-10 and IL-13 were measured by reverse transcription polymerase chain reaction. Modified disease activity index were used to analyse the severity of the disease by assessed of diarrhea, stool (occult) blood and body weight loss of the mice. Results: Compared with control and model groups, modified disease activity index in baicalin and mesalazine treated, mice decreased gradually. Immunohistochemistry analysis showed the expression of TLR4, but not TLR2 and TLR9, in the mucosa of mice colon were decreased. Western blot analysis showed that in colitis model, the expression of NF-?B p65 and TLR4 decreased (P < 0.05), while the expression of MyD88 increased significantly compared to control group, and MyD88 expression can not be repressed by baicalin (P < 0.05). Baicalin and mesalazine treatment suppressed the expression of TNF-?, IL-6 and IL-13 mRNA (P < 0.05), yet up-regulated the expression of IL-10 mRNA (P < 0.05), compared to the DDS and control groups. Conclusions: Baicalin administration by intragastric injection ameliorates the severity of colon inflammation. The possible mechanism of anti-inflammatory response by baicalin may involve in the blocking of the TLR4/NF-?B-p65/IL-6 signaling pathway. PMID:25550915

Feng, Jinshan; Guo, Cancan; Zhu, Yuzhen; Pang, Liping; Yang, Zheng; Zou, Ying; Zheng, Xuebao

2014-01-01

280

Purification and Properties of a Highly Thermostable, Sodium Dodecyl Sulfate-Resistant and Stereospecific Proteinase from the Extremely Thermophilic Archaeon Thermococcus stetteri  

PubMed Central

The cultivation of the extremely thermophilic archaeon Thermococcus stetteri in a dialysis membrane reactor was paralleled by the production of an extremely heat-stable proteinase(s). By applying preparative sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis, an SDS-resistant proteinase was purified 67-fold in one step with a yield of 34%. The purified enzyme, which was composed of a single polypeptide chain with a molecular mass of 68 kDa, showed a broad temperature and pH profile (50 to 100(deg)C; pH 5 to 11). The optimal activity with substantial thermal stability was measured with casein at 85(deg)C and pH 8.5 to 9. Inhibition by phenylmethylsulfonyl fluoride and diisopropylfluorophosphate demonstrated that the enzyme was a serine proteinase. The enzyme displayed a relatively narrow substrate specificity, catalyzing the hydrolysis only of N-protected p-nitroanilides or p-nitrophenyl esters of basic (Arg or Lys) or hydrophobic (Phe or Tyr) l-amino acids. l-Phenylglycine amide was also attacked by the proteinase, but with a lower specificity constant. Within the detection limit, no hydrolysis of d-amino acid derivatives was observed. The catalytic efficiency of the enzyme at 80(deg)C (k(infcat)/K(infm) for benzoyl-Arg-p-nitroanilide, 10(sup4)) is the same order of magnitude when compared with that of functionally similar mesophilic enzymes. The proteinase also acts as a transferase, catalyzing the acyl transfer from protected amino acid ester or amide to amino acid amide. The observed thermostability, SDS resistance, relatively narrow substrate specificity, high stereospecificity, and limited catalytic efficiency probably reflect the tighter packing of the thermostable protein molecule and its limited flexibility. This was supported by fluorescence spectra of the enzyme, mainly due to tryptophan residues, in the temperature range of 30 to 90(deg)C. Structural reorganization was observed at temperatures over 100(deg)C. The results obtained could be of relevance for the better understanding of the structure-function relationship of enzymes from extreme thermophiles and suggest possible biotechnological application of the proteinase for resolution of racemic mixtures. PMID:16535107

Klingeberg, M.; Galunsky, B.; Sjoholm, C.; Kasche, V.; Antranikian, G.

1995-01-01

281

Management of Bleeding Duodenal Varices with Combined TIPS Decompression and Trans-TIPS Transvenous Obliteration Utilizing 3% Sodium Tetradecyl Sulfate Foam Sclerosis  

PubMed Central

Objectives: Endoscopic experience in the management of duodenal varices (DVs) is limited and challenging given the anatomic constraints and limited experience. The endovascular management of DVs is not yet established and the controversy of whether to manage them by decompression with a transjugular intrahepatic portosystemic shunt (TIPS) or by transvenous obliteration is unresolved. In the literature, the 6–12 month rebleeding rate of DVs after TIPS is 21-37% and after transvenous obliteration is 13%. The purpose of the study is to evaluate the clinical outcome of combined TIPS decompression and transvenous obliteration/sclerosis. Materials and Methods: This is a retrospective study (case series) of two institutions, evaluating patients who underwent TIPS and/or transvenous obliteration/sclerosis for bleeding DVs (from January 2009 to June 2013). TIPS was performed according to a standard procedure using covered stents. Transvenous obliteration (variceal sclerosis) from the systemic and/or portal venous circulation was performed utilizing 3% sodium tetradecyl sulfate foam. Transvenous obliteration was commonly augmented with coils and/or vascular plugs. Technical (technical success of establishing TIPS and completely obliterating the DVs) and clinical outcomes (rebleeding rate and survival) were evaluated. Results: Five patients with liver cirrhosis presenting with bleeding DVs were included in the study with all eventually (and coincidentally) receiving TIPS and transvenous obliteration. Two of the five patients underwent concomitant TIPS and transvenous obliteration in the same procedural setting. However, three patients underwent transvenous obliteration due to bleeding despite a patent TIPS that had been previously placed. The average time from TIPS placement to transvenous obliteration was 125 days (range: 3-324 days). After having both procedures, there was no rebleeding in the patients during a mean follow-up period of 22 months (6–50 months). Coils and/or metallic vascular plugs were used to augment the sclerosant obliteration in four of five patients. Conclusion: The combination of TIPS decompression and foam sclerosant transvenous obliteration appears to be effective in preventing rebleeding in this limited case series and compares favorably with the existing evidence for either approach [TIPS or balloon-occluded retrograde transvenous obliteration (BRTO)] alone.

Saad, Wael E; Lippert, Allison; Schwaner, Sandra; Al-Osaimi, Abdullah; Sabri, Saher; Saad, Nael

2014-01-01

282

Patch testing with the irritant sodium lauryl sulfate (SLS) is useful in interpreting weak reactions to contact allergens as allergic or irritant.  

PubMed

Several contact allergens are tested at concentrations which might cause irritant reactions. In this study we investigated whether the reactivity to a standard irritant is useful in identifying subjects with hyperreactive skin yielding a higher rate of doubtful or irritant reactions. Sodium lauryl sulfate (SLS) 0.5% (aqua) was tested in addition to the standard series routinely for 5 years in the Department of Dermatology, Dortmund. For data analysis, we compared reactions at D3 to the standard series, the vehicle/emulsifier and preservative series and benzoyl peroxide to the reactions obtained with SLS. Proportions were standardized for age and sex. The association between reactivity to a certain allergen and SLS reactivity as a dichotomous outcome, controlled for age and sex as potential confounders, was assessed with logistic regression analysis. Results showed that of the 1600 tested patients, 668 (41.8%) had an irritant reaction to SLS which exceeded 2 + in only 41 patients. Seasonal variation was statistically significant, showing reduced SLS reactivity in summer vs. winter. Patients with irritant reactions to SLS showed significantly more erythematous reactions to the following 10 allergens of the standard series: fragrance mix, cobalt chloride, balsam of Peru (Myroxylon pereirae), lanolin alcohol, 4-phenylenediamine base (PPD), propolis, formaldehyde, N-isopropyl-N'-phenyl-p-phenylenediamine (IPPD), benzocaine, and 4-tert-butylphenol-formaldehyde resin. No significant differences regarding strong positive allergic reactions were observed. Concerning other allergens, significantly more erythematous reactions were observed in SLS-reactive patients to benzoyl peroxide, octyl gallate, cocamidopropyl betaine, Amerchol L-101, tert-butylhydroquinone, and triethanolamine. In the SLS-reactive group of patients, the reaction index was negative for 10 allergens of the standard series compared to only 5 in the SLS non-responder group. For the first time, this study, based on a large data pool, revealed a significant association between reactivity to the irritant SLS and erythematous reactions to certain allergens. With SLS as a marker for hyperreactive skin at hand, some of these reactions can now be classified as irritant more confidently, particularly if there is no history of exposure to the allergen. PMID:12694214

Geier, J; Uter, W; Pirker, C; Frosch, P J

2003-02-01

283

Synthesis and evaluation of sodium deoxycholate sulfate as a lipid drug carrier to enhance the solubility, stability and safety of an amphotericin B inhalation formulation.  

PubMed

Amphotericin B (AmB) is still used as the gold standard for therapy against invasive fungal diseases. However, the use of AmB through oral administration is restricted due to its low solubility and stability in aqueous solution, which is the cause for its poor bioavailability and highly varying absorption. Therefore, an attempt has been made to enhance the solubility and stability of AmB to evaluate its bioactivity and safety for use as an inhaler by using a new excipient sodium deoxycholate sulfate (SDS) with aim of using it as a drug carrier for AmB. Therefore, SDS was formulated together with AmB as a dry powder by lyophilization. The dry powder was reconstituted in distilled water and evaluated its physicochemical properties such as zeta potential, particle size and pH to compare its solubility and stability of the formulations with a SDC-AmB (i.e., known as Fungizone(®)). In vitro toxicity studies were carried out with red blood cells (RBC) and respiratory cell lines. Bioactivity was determined by a micro-dilution method against Candidaalbicans and Cryptococcusneoformans. We found that SDS-AmB had a zeta potential (-45.53 mV), which was higher than of Fungizone(®); and produced a stable particle size in solution (73.8 nm). The particle size distributions of both formulations were expressed as their mass median aerodynamic diameters (MMAD; 1.70 and 1.74 ?m), their fine particle fractions (FPF; 70 and 80%) and geometric standard deviations (GSD; 2.3 and 2.0), respectively. These values indicated that the sizes were appropriate for use in an inhaler. Pure AmB was found to hemolyse RBC and was very toxic to alveolar macrophage cells, as their viability rapidly declined from 93 to 56% when the AmB concentration increased from 1 to 8 ?g/mL. The SDS-AmB formulation had a significantly reduced toxicity compared to AmB. The results clearly indicated that the SDS-lipid based nanoparticles had the potential to be used as an alternative option to Fungizone(®) for an AmB formulation for inhalation. PMID:24907597

Gangadhar, Katkam N; Adhikari, Kajiram; Srichana, Teerapol

2014-08-25

284

Reductions of Shiga toxin-producing Escherichia coli and Salmonella typhimurium on beef trim by lactic acid, levulinic acid, and sodium dodecyl sulfate treatments.  

PubMed

Studies were done at 21 °C to determine the bactericidal activity of lactic acid, levulinic acid, and sodium dodecyl sulfate (SDS) applied individually and in combination on Shiga toxin-producing Escherichia coli (STEC) in pure culture and to compare the efficacy of lactic acid and levulinic acid plus SDS treatments applied by spray or immersion to inactivate STEC and Salmonella (10(7) CFU/cm2) on beef trim pieces (10 by 10 by 7.5 cm). Application of 3% lactic acid for 2 min to pure cultures was shown to reduce E. coli O26:H11, O45:H2, O111:H8, O103:H2, O121:H2, O145:NM, and O157:H7 populations by 2.1, 0.4, 0.3, 1.4, 0.3, 2.1, and 1.7 log CFU/ml, respectively. Treatment with 0.5% levulinic acid plus 0.05% SDS for <1 min reduced the populations of all STEC strains to undetectable levels (>6 log/ml reduction). Beef surface temperature was found to affect the bactericidal activity of treatment with 3 % levulinic acid plus 2% SDS (LV-SDS). Treating cold (4 °C) beef trim with LV-SDS at 21, 62, or 81 °C for 30 s reduced E. coli O157:H7 by 1.0, 1.1, or 1.4 log CFU/cm2, respectively, whereas treating beef trim at 8 °C with LV-SDS at 12 °C for 0.1, 1, 3, or 5 min reduced E. coli O157:H7 by 1.4, 2.4, 2.5, or 3.3 log CFU/cm(2), respectively. Spray treatment of beef trim at 4 °C with 5 % lactic acid only reduced the E. coli O157:H7 population by 1.3 log CFU/cm2. Treating beef trim at 8 °C with LV-SDS for 1, 2, or 3 min reduced Salmonella Typhimurium by 2.1, 2.6, and >5.0 log CFU/cm2, respectively. Hand massaging the treated beef trim substantially reduced contamination of both pathogens, with no detectable E. coli O157:H7 or Salmonella Typhimurium (<5 CFU/cm2) on beef trim pieces treated with LV-SDS. Reduction of E. coli O157:H7 and Salmonella Typhimurium populations was enhanced, but bactericidal activity was affected by the meat temperature. PMID:24680063

Zhao, Tong; Zhao, Ping; Chen, Dong; Jadeja, Ravirajsinh; Hung, Yen-Con; Doyle, Michael P

2014-04-01

285

Increased CYP4B1 mRNA Is Associated with the Inhibition of Dextran Sulfate Sodium-Induced Colitis by Caffeic Acid in Mice  

PubMed Central

Susceptibility to inflammatory bowel diseases depends upon interactions between the genetics of the individual and induction of chronic mucosal inflammation. We hypothesized that administration of dietary phenolics, caffeic acid and rutin, would suppress upregulation of inflammatory markers and intestinal damage in a mouse model of colitis. Colitis was induced in C3H/HeOuJ mice (8 wk old, 6 male/6 female per treatment) with 1.25% dextran sulfate sodium (DSS) for 6 d in their drinking water. Rutin (1.0 mmol (524 mg)/kg in diet), caffeic acid (1.0 mmol (179 mg)/kg in diet), and hypoxoside extract (15 mg/d, an anticolitic phenolic control) were fed for 7 d before and during DSS treatment, as well as without DSS treatment. Body weight loss was prevented by rutin and caffeic acid during DSS treatment. Colon lengths in mice fed caffeic acid and hypoxoside during DSS treatment were similar to DSS-negative control. Food intake was improved and myeloperoxidase (MPO) was decreased with each phenolic treatment in DSS-treated mice compared with DSS treatment alone. Colonic mRNA expression of IL-17 and iNOS were inhibited when IL-4 was increased by each phenolic treatment combined with DSS, whereas CYP4B1 mRNA was increased only by caffeic acid in DSS-treated mice, compared with DSS treatment alone. Colonic and cecal histopathology scores of DSS-treated mice were significantly more severe (P< 0.01) than in mice fed caffeic acid before and during DSS treatment based on mucosal height, necrosis, edema, erosion, and inflammatory cell infiltration. Although both rutin and caffeic acid suppressed the expression of selected inflammatory markers, only caffeic acid protected against DSS induced colitis, in association with normalization of CYP4B1 expression. The inhibition of DSS-induced colitic pathology by caffeic acid was mediated by mechanisms in addition to anti-inflammatory effects that deserve further study. PMID:19307459

Ye, Zhong; Liu, Zhiping; Henderson, Abigail; Lee, Kwangwon; Hostetter, Jesse; Wannemuehler, Michael; Hendrich, Suzanne

2013-01-01

286

Bacterial Sulfite-Oxidizing Enzymes – Enzymes for Chemolithotrophs Only?  

Microsoft Academic Search

All known sulfite-oxidizing enzymes that have been studied in molecular detail belong to the sulfite oxidase family of molybdoenzymes.\\u000a The first bacterial enzymes in this family were only characterized in 2000, but by now it has become clear that bacterial\\u000a enzymes originating from many different types of bacteria may actually be the most abundant proteins in this enzyme family.\\u000a This

Ulrike Kappler

287

The interaction of borate and sulfite with pyridine nucleotides.  

PubMed

The kinetics and equilibria of the borate interaction at ribose with NAD+ and NMN+ have been measured using as a chromophoric probe the perturbation effect borate has on the addition of sulfite to the 4 position of the nicotinamide ring. NAD+ and NMN+ have more favorable borate association constants than do their corresponding sulfite addition complexes. The rate of interaction of the ribose moiety with borate at low borate buffer concentration is dependent on the concentration of both borate and boric acid. At high borate concentration the rate becomes independent of borate concentration, indicating the existence of a two-step process for the interaction of NAD-sulfite with borate with a change of rate-determining step from the interaction of the ribose hydroxyl group with borate at low borate to an elimination of sulfite at high borate concentration. A linear free energy relationship with a slope of 0.94 describes an increased reactivity of the nucleotide for sulfite as the affinity of the nucleotide for sulfite increases. PMID:3201

Johnson, S L; Smith, K W

1976-02-10

288

Electronic and photophysical properties of adducts of [Ru(bpy)3]2+ and Dawson-type sulfite polyoxomolybdates ?/?-[Mo18O54(SO3)2]4-.  

PubMed

The spectroscopic and photophysical properties of [Ru(bpy)(3)](2)[[Mo(18)O(54)(SO(3))(2)], where bpy is 2,2'-bipyridyl and [Mo(18)O(54)(SO(3))(2)](4-) is either the ? or ?-sulfite containing polyoxomolybdate isomer, have been measured and compared with those for the well known but structurally distinct sulfate analogue, ?-[Mo(18)O(54)(SO(4))(2)](4-). Electronic difference spectroscopy revealed the presence of new spectral features around 480 nm, although they are weak in comparison with the [Ru(bpy)(3)](2)[Mo(18)O(54)(SO(4))(2)] analogue. Surprisingly, Stern-Volmer plots of [Ru(bpy)(3)](2+) luminescence quenching by the polyoxometallate revealed the presence of both static and dynamic quenching for both ? and ?-[Mo(18)O(54)(SO(3))(2)](4-). The association constant inferred for the ion cluster [Ru(bpy)(3)](2)?-[Mo(18)O(54)(SO(4))(2)] is K = 5.9 ± 0.56 × 10(6) and that for [Ru(bpy)(3)](2)?-[Mo(18)O(54)(SO(4))(2)] is K = 1.0 ± 0.09 × 10(7). Unlike the sulfate polyoxometalates, both sulfite polyoxometalate-ruthenium adducts are non-luminescent. Despite the strong electrostatic association in the adducts resonance Raman and photoelectrochemical studies suggests that unlike the sulfato polyoxometalate analogue there is no sensitization of the polyoxometalate photochemistry by the ruthenium centre for the sulfite anions. In addition, the adducts exhibit photochemical lability in acetonitrile, attributable to decomposition of the ruthenium complex, which has not been observed for other [Ru(bpy)(3)](2+) -polyoxometalate adducts. These observations suggest that less electronic communication exists between the [Ru(bpy)(3)](2+) and the sulfite polyoxoanions relative to their sulfate polyoxoanion counterparts, despite their structural and electronic analogy. The main distinction between sulfate and sulfite polyoxometalates lies in their reversible reduction potentials, which are more positive by approximately 100 mV for the sulfite anions. This suggests that the capacity for [Ru(bpy)(3)](2+) or analogues to sensitize photoreduction in the adducts of polyoxometalates requires very sensitive redox tuning. PMID:21258724

Walsh, James J; Long, De-Liang; Cronin, Leroy; Bond, Alan M; Forster, Robert J; Keyes, Tia E

2011-03-01

289

The octaheme SirA catalyses dissimilatory sulfite reduction in Shewanella oneidensis MR-1  

SciTech Connect

Shewanella oneidensis MR-1 is a metal reducer that uses a large number of electron acceptors that include thiosulfate, polysulfide, and sulfite. The enzyme required for thiosulfate and polysulfide respiration has been recently identified, but the mechanisms of sulfite reduction remained unexplored. Analysis of MR-1 cultures grown anaerobically with sulfite suggested that the dissimilatory sulfite reductase catalyzes six-electron reduction of sulfite to sulfide. Reduction of sulfite required menaquinones and c cytochromes but appeared to be independent of the intermediate electron carrier CymA. Furthermore, the terminal sulfite reductase, SirA, was identified as an octaheme c cytochrome with an atypical heme binding site that represents a new class of sulfite reductases. The sirA locus was identified in the genomes of several sequenced Shewanella genomes, and its presence appears to be linked to the ability of these organisms to reduce sulfite under anaerobic conditions.

Shirodkar, Sheetal; Reed, Samantha B.; Romine, Margaret F.; Saffarini, Daad

2011-01-01

290

A fast and sensitive HPLC method for sulfite analysis in food based on a plant sulfite oxidase biosensor  

Microsoft Academic Search

A reliable and sensitive analysis of sulfites in food is essential in food monitoring. However, the established methods exhibit deficiencies in the very low concentration ranges (below 10mg\\/L SO2), especially with more complex food matrices. With a focus on these challenges, an HPLC method with immobilized enzyme reactor (HPLC–IMER) for the analysis of sulfites in food was optimized and compared

S. Theisen; R. Hänsch; L. Kothe; U. Leist; R. Galensa

2010-01-01

291

Evaluation of microbial diversity in sulfite-added and sulfite-free wine by culture-dependent and -independent methods.  

PubMed

The difference in microbiota including non-lactic acid bacteria, non-acetic acid bacteria, and wild yeast during winemaking and in the end-products between sulfite-added and sulfite-free wine, was investigated using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and a culture-dependent method. There were differences between the microorganisms detected by PCR-DGGE and those detected by the culture-dependent method, probably because of the selectivity of culture medium and the characteristics of PCR-based method. In both the red wine and white wine, the microbial diversity of the sulfite-added wine was lower than that of the sulfite-free wine during fermentation. Tatumella terrea was detected from the fermenting must by PCR-DGGE and by the culture-dependent method, even though sulfite inhibited its growth to some extent. We confirmed that the addition of sulfite plays an important role in winemaking by inhibiting the growth of unexpected microorganisms, but on the other hand, it was revealed that some microorganisms can survive and grow in sulfite-added fermenting must. We also analyzed 15 samples of commercial wines by the PCR-DGGE method and detected various microorganisms. Among them, Sphingomonas sp., Pseudozyma sp., Ochromonas sp. and Methylophilus sp. were found for the first time in wine as far as we know. We did not identify a specific microorganism that was detected only from wines without sulfite addition. Thus, the microbiota of end-products seemed to be influenced by other factors, such as filtration before bottling, the production equipment and the storage environment. PMID:24239025

Takahashi, Masayuki; Ohta, Tami; Masaki, Kazuo; Mizuno, Akihiro; Goto-Yamamoto, Nami

2014-05-01

292

Redox states of Desulfovibrio vulgaris DsrC, a key protein in dissimilatory sulfite reduction  

SciTech Connect

Dissimilatory reduction of sulfite is carried out by the siroheme enzyme DsrAB, with the involvement of the protein DsrC having two conserved cysteine residues. Here, we report a study of the distribution of DsrC in cell extracts, a cysteine-labelling gel-shift assay to monitor its redox state and behaviour, and procedures to produce the different redox forms. We show that, in the model sulfate reducer Desulfovibrio vulgaris, the majority of DsrC is not associated with DsrAB and is thus free to interact with other proteins. In addition, we successfully produced DsrC with an intramolecular disulfide bond (oxidized state) by treatment with arginine.

Venceslau, Sofia S.; Cort, John R.; Baker, Erin Shammel; Chu, Rosalie K.; Robinson, Errol W.; Dahl, Christiane; Saraiva, Ligia M.; Pereira, Ines Ac

2013-11-29

293

Estimate of intake of sulfites in the Belgian adult population.  

PubMed

An exposure assessment was performed to estimate the usual daily intake of sulfites in the Belgian adult population. Food consumption data were retrieved from the national food consumption survey. In a first step, individual food consumption data were multiplied with the maximum permitted use levels for sulfites, expressed as sulphur dioxide, per food group (Tier 2). In a second step, on the basis of a literature review of the occurrence of sulfites in different foods, the results of the Tier 2 exposure assessment and available occurrence data from the control programme of the competent authority, a refined list of foods was drafted for the quantification of sulphite. Quantification of sulphite was performed by a high-performance ion chromatography method with eluent conductivity detector in beers and potato products. Individual food consumption data were then multiplied with the actual average concentrations of sulfite per food group, or the maximum permitted levels in case actual levels were not available (partial Tier 3). Usual intakes were calculated using the Nusser method. The mean intake of sulfites was 0.34 mg kg(-1) bw day(-1) (Tier 2), corresponding to 49% of the acceptable daily intake (ADI) and 0.19 mg kg(-1) bw day(-1), corresponding to 27% of the ADI (partial Tier 3). The food group contributing most to the intake of sulfites was wines. The results showed that the intake of sulfites is likely to be below the ADI in Belgium. However, there are indications that high consumers of wine have an intake around the ADI. PMID:20503127

Vandevijvere, S; Temme, E; Andjelkovic, M; De Wil, M; Vinkx, C; Goeyens, L; Van Loco, J

2010-08-01

294

Improvements in amperometric detection of sulfite in food matrixes.  

PubMed

Sulfite is added to foods as an antimicrobial, antibrowning agent, or antioxidant. It also can occur naturally, and is often used in the production of beer and wine. For years the standard methodology for determination of sulfite in foods has been the Monier-Williams method, which is a combination of acid distillation and titration. Recently, AOAC adopted a chromatographic method based on a method developed by Kim and Kim for the determination of sulfite. The method combines ion exclusion chromatography with direct-current (DC) amperometric detection to provide more convenient and accurate quantitation of sulfite. However, fouling of the platinum working electrode results in a rapid decrease in method sensitivity. As a result, standards must be injected before and after every sample, and the electrode must be polished frequently to maintain adequate detection limits. Pulsed amperometric detection overcomes electrode fouling problems by repeatedly and continuously applying cleaning potentials to the working electrode. Using this technique, a reproducible electrode surface can be maintained, and injection-to-injection repeatability is greatly improved. A comparison of method performance for both DC and pulsed amperometric detection is presented. Also investigated was the stability of sulfite samples at varying pH, and in the presence or absence of a preservative. PMID:9419871

Wygant, M B; Statler, J A; Henshall, A

1997-01-01

295

The antibrowning agent sulfite inactivates Agaricus bisporus tyrosinase through covalent modification of the copper-B site.  

PubMed

Sulfite salts are widely used as antibrowning agents in food processing. Nevertheless, the exact mechanism by which sulfite prevents enzymatic browning has remained unknown. Here, we show that sodium hydrogen sulfite (NaHSO3) irreversibly blocks the active site of tyrosinase from the edible mushroom Agaricus bisporus, and that the competitive inhibitors tropolone and kojic acid protect the enzyme from NaHSO3 inactivation. LC-MS analysis of pepsin digests of NaHSO3 -treated tyrosinase revealed two peptides showing a neutral loss corresponding to the mass of SO3 upon MS(2) fragmentation. These peptides were found to be homologous peptides containing two of the three histidine residues that form the copper-B-binding site of mushroom tyrosinase isoform PPO3 and mushroom tyrosinase isoform PPO4, which were both present in the tyrosinase preparation used. Peptides showing this neutral loss behavior were not found in the untreated control. Comparison of the effects of NaHSO3 on apo-tyrosinase and holo-tyrosinase indicated that inactivation is facilitated by the active site copper ions. These data provide compelling evidence that inactivation of mushroom tyrosinase by NaHSO3 occurs through covalent modification of a single amino-acid residue, probably via addition of HSO3(-) to one of the copper-coordinating histidines in the copper-B site of the enzyme. PMID:24112416

Kuijpers, Tomas F M; Gruppen, Harry; Sforza, Stefano; van Berkel, Willem J H; Vincken, Jean-Paul

2013-12-01

296

21 CFR 201.22 - Prescription drugs containing sulfites; required warning statements.  

...anaphylactic symptoms and life-threatening or less severe asthmatic episodes in certain susceptible people. The overall prevalence of sulfite sensitivity in the general population is unknown and probably low. Sulfite sensitivity is seen more frequently in...

2014-04-01

297

21 CFR 201.22 - Prescription drugs containing sulfites; required warning statements.  

Code of Federal Regulations, 2012 CFR

...anaphylactic symptoms and life-threatening or less severe asthmatic episodes in certain susceptible people. The overall prevalence of sulfite sensitivity in the general population is unknown and probably low. Sulfite sensitivity is seen more frequently in...

2012-04-01

298

21 CFR 201.22 - Prescription drugs containing sulfites; required warning statements.  

Code of Federal Regulations, 2010 CFR

...anaphylactic symptoms and life-threatening or less severe asthmatic episodes in certain susceptible people. The overall prevalence of sulfite sensitivity in the general population is unknown and probably low. Sulfite sensitivity is seen more frequently in...

2010-04-01

299

21 CFR 201.22 - Prescription drugs containing sulfites; required warning statements.  

Code of Federal Regulations, 2013 CFR

...anaphylactic symptoms and life-threatening or less severe asthmatic episodes in certain susceptible people. The overall prevalence of sulfite sensitivity in the general population is unknown and probably low. Sulfite sensitivity is seen more frequently in...

2013-04-01

300

21 CFR 201.22 - Prescription drugs containing sulfites; required warning statements.  

Code of Federal Regulations, 2011 CFR

...anaphylactic symptoms and life-threatening or less severe asthmatic episodes in certain susceptible people. The overall prevalence of sulfite sensitivity in the general population is unknown and probably low. Sulfite sensitivity is seen more frequently in...

2011-04-01

301

Chondroitin sulfate  

MedlinePLUS

... sulfate is manufactured from animal sources, such as cow cartilage. Chondroitin sulfate is used for osteoarthritis. It ... those that might transmit bovine spongiform encephalopathy (mad cow disease). So far, there are no reports of ...

302

Barium Sulfate  

MedlinePLUS

Cheetah® ... Barium sulfate is used to help doctors examine the esophagus (tube that connects the mouth and stomach), stomach, ... dimensional pictures of the inside of the body). Barium sulfate is in a class of medications called radiopaque ...

303

Monosaccharide production in an acid sulfite process: kinetic modeling.  

PubMed

Spent sulfite liquor is a lignocellulosic waste obtained after the sulfite pulping process. It is mainly formed by sugars and lignosulfonates which are isolated from the pulp during the cooking process. The current work investigates the kinetic modeling of the sulfite process from a biorefinery point of view since monosaccharides present in the spent liquor can be used as a raw material in further biorefinery processes to produce other value-added products. Kinetic parameters of carbohydrate degradation have been determined following sugar and inhibitors from wood to spent liquor, using laboratory scale reactors and different temperatures, 130, 140 and 150 °C. Three types of reaction schemes were developed. Kinetic parameters were obtained for each one using first and n order reactions, using Aspen Custom Modeler. Results show that the best temperature to be used in the process is 130 °C, giving the maximum sugar conversion, 33.91 mol% and obtaining 13.81 mol% of decomposition products. PMID:25458268

Rueda, C; Fernández-Rodríguez, J; Ruiz, G; Llano, T; Coz, A

2015-02-13

304

Oxygen scavengers - The chemistry of sulfite under hydrothermal conditions  

SciTech Connect

Control of oxygen corrosion is critical to the reliability of steam generator systems. Mechanical deaeration and chemical oxygen scavenging effectively reduce oxygen levels in boiler feedwater systems. This paper reviews the use of sulfites to reduce oxygen and provide corrosion control throughout the boiler feedwater circuit as well as mechanical and operational oxygen reduction methods. The mechanism of oxygen pitting, electrochemical reactions, and the basis of operation of mechanical deaeration are discussed. Estimating techniques for the amount of steam required and a deaerator troubleshooting guide are included. The chemistry of sulfites is covered in detail. Also included are a functional definition of chemical oxygen scavengers and a general discussion of their various types.

Cotton, I.J.

1987-03-01

305

Sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL) for robust enzymatic saccharification of hardwoods.  

PubMed

This study demonstrates sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL) for robust bioconversion of hardwoods. With only about 4% sodium bisulfite charge on aspen and 30-min pretreatment at temperature 180 degrees C, SPORL can achieve near-complete cellulose conversion to glucose in a wide range of pretreatment liquor of pH 2.0-4.5 in only about 10 h enzymatic hydrolysis. The enzyme loading was about 20 FPU cellulase plus 30 CBU beta-glucosidase per gram of cellulose. The production of fermentation inhibitor furfural was less than 20 mg/g of aspen wood at pH 4.5. With pH 4.5, SPORL avoided reactor corrosion problem and eliminated the need for substrate neutralization prior to enzymatic hydrolysis. Similar results were obtained from maple and eucalyptus. PMID:19551888

Wang, G S; Pan, X J; Zhu, J Y; Gleisner, R; Rockwood, D

2009-01-01

306

Coupled sulfur and oxygen isotope insight into bacterial sulfate reduction in the natural environment  

NASA Astrophysics Data System (ADS)

We present new sulfur and oxygen isotope data in sulfate (?34SSO4 and ?18OSO4, respectively), from globally distributed marine and estuary pore fluids. We use this data with a model of the biochemical steps involved in bacterial sulfate reduction (BSR) to explore how the slope on a ?18OSO4 vs. ?34SSO4 plot relates to the net sulfate reduction rate (nSRR) across a diverse range of natural environments. Our data demonstrate a correlation between the nSRR and the slope of the relative evolution of oxygen and sulfur isotopes (?18OSO4 vs. ?34SSO4) in the residual sulfate pool, such that higher nSRR results in a lower slope (sulfur isotopes increase faster relative to oxygen isotopes). We combine these results with previously published literature data to show that this correlation scales over many orders of magnitude of nSRR. Our model of the mechanism of BSR indicates that the critical parameter for the relative evolution of oxygen and sulfur isotopes in sulfate during BSR in natural environments is the rate of intracellular sulfite oxidation. In environments where sulfate reduction is fast, such as estuaries and marginal marine environments, this sulfite reoxidation is minimal, and the ?18OSO4 increases more slowly relative to the ?34SSO4. In contrast, in environments where sulfate reduction is very slow, such as deep sea sediments, our model suggests sulfite reoxidation is far more extensive, with as much as 99% of the sulfate being thus recycled; in these environments the ?18OSO4 increases much more rapidly relative to the ?34SSO4. We speculate that the recycling of sulfite plays a physiological role during BSR, helping maintain microbial activity where the availability of the electron donor (e.g. available organic matter) is low.

Antler, Gilad; Turchyn, Alexandra V.; Rennie, Victoria; Herut, Barak; Sivan, Orit

2013-10-01

307

Preparation, Characterization, and Selectivity Study of Mixed-Valence Sulfites  

ERIC Educational Resources Information Center

A project involving the synthesis of an isomorphic double sulfite series and characterization by classical inorganic chemical analyses is described. The project is performed by upper-level undergraduate students in the laboratory. This compound series is suitable for examining several chemical concepts and analytical techniques in inorganic…

Silva, Luciana A.; de Andrade, Jailson B.

2010-01-01

308

CHARACTERIZATION OF CARBIDE LIME TO IDENTIFY SULFITE OXIDATION INHIBITORS  

EPA Science Inventory

The report gives results of a study of carbide lime--a by-product of acetylene manufacture, primarily calcium hydroxide--used in a flue gas desulfurization (FGD) system at Louisville Gas and Electric (LGE). The study was undertaken to: identify sulfite ion oxidation inhibitors in...

309

Clonal mast cell activation syndrome with anaphylaxis to sulfites.  

PubMed

Sulfites are rarely suspected as causative agents of immediate-type hypersensitivity. We report on a 49-year-old male patient who developed recurrent severe hypotension after food ingestion. A diagnosis of monoclonal mast cell activation syndrome was established. In the double-blind, placebo-controlled food challenge, the patient reacted to potassium metabisulfite with anaphylaxis. PMID:23816954

Cifuentes, Liliana; Ring, Johannes; Brockow, Knut

2013-01-01

310

Fortifying spent sulfite pulping liquor with hydrolyzed reject knots  

Microsoft Academic Search

A limitation for spent sulfite liquor (SSL) fermentation, particularly hardwood SSL fermentation is the low sugar content. The objective of this work was to increase the sugar content of SSL through the addition and hydrolysis of reject knots from the pulp line.Factorial experiments indicated that hydrolysis yield was significantly affected by cellulase and ?-glucosidase loading, concentration of SSL, knot concentration,

Steve S. Helle; Robert A. Petretta; Sheldon J. B. Duff

2007-01-01

311

Evaluation of intra-articular hyaluronan, sodium chondroitin sulfate and N-acetyl-D-glucosamine combination versus saline (0.9% NaCl) for osteoarthritis using an equine model.  

PubMed

A randomized blinded placebo controlled trial was conducted to assess the clinical, biochemical and histological effects of a hyaluronan, sodium chondroitin sulfate and N-acetyl-D-glucosamine combination (PG) administered through an intra-articular (IA) route for the treatment of osteoarthritis (OA) at the time of injury. OA was induced in one carpal joint of each of 16 horses. Horses were designated placebo or IA PG treated. All horses were treated with 125 mg amikacin sulfate IA and 5 mL physiological saline in the middle carpal joint bilaterally on study Days 0 (after induction of OA), 7, 14 and 28, except the OA affected joint of the IA PG horses, which received 5 mL PG plus 125 mg of amikacin sulfate on similar days. Evaluations included clinical and radiographic, synovial fluid analysis, gross and histological examinations, as well as histochemical and biochemical analyses. The model induced a significant pathology that resulted in clinical disease. No adverse treatment-related events were detected in any of the horses. Intra-articular treatment of OA-affected joints with PG resulted in a transient 16% improvement in clinical pain (lameness scores) and evidence of improvement trends in bone proliferation radiographically as well as in the degree of full thickness articular cartilage erosion seen grossly when compared to placebo treated OA affected joints, although the vast majority of outcome parameters were not significantly different than controls. The findings support some potential clinical sign or disease modifying action of this compound administered IA at the tested dose and frequency. PMID:23838209

Frisbie, D D; McIlwraith, C W; Kawcak, C E; Werpy, N M

2013-09-01

312

HIGH-RESOLUTION EPR SPECTROSCOPY OF MO ENZYMES. SULFITE OXIDASES: STRUCTURAL AND FUNCTIONAL IMPLICATIONS  

PubMed Central

Sulfite oxidases (SOs) are physiologically vital Mo-containing enzymes that occur in animals, plants, and bacteria and which catalyze the oxidation of sulfite to sulfate, the terminal reaction in the oxidative degradation of sulfur-containing compounds. X-ray structure determinations of SOs from several species show nearly identical coordination structures of the molybdenum active center, and a common catalytic mechanism has been proposed that involves the generation of a transient paramagnetic Mo(V) state through a series of coupled electron–proton transfer steps. This chapter describes the use of pulsed electron-nuclear double resonance (ENDOR) and electron spin echo envelope modulation (ESEEM) spectroscopic techniques to obtain information about the structure of this Mo(V) species from the hyperfine interactions (hfi) and nuclear quadrupole interactions (nqi) of nearby magnetic nuclei. Variable frequency instrumentation is essential to optimize the experimental conditions for measuring the couplings of different types of nuclei (e.g., 1H, 2H, 31P, and 17O). The theoretical background necessary for understanding the ESEEM and ENDOR spectra of the Mo(V) centers of SOs is outlined, and examples of the use of advanced pulsed EPR methods (RP-ESEEM, HYSCORE, integrated four-pulse ESEEM) for structure determination are presented. The analysis of variable-frequency pulsed EPR data from SOs is aided by parallel studies of model compounds that contain key functional groups or that are isotopically labeled and thus provide benchmark data for enzymes. Enormous progress has been made on the use of high-resolution variable-frequency pulsed EPR methods to investigate the structures and mechanisms of SOs during the past ~15 years, and the future is bright for the continued development and application of this technology to SOs, other molybdenum enzymes, and other problems in metallobiochemistry. PMID:21283528

Enemark, John H.; Astashkin, A.V.; Raitsimring, A.M.

2011-01-01

313

Role of sulfite additives in wine induced asthma: single dose and cumulative dose studies  

PubMed Central

BACKGROUND—Wine appears to be a significant trigger for asthma. Although sulfite additives have been implicated as a major cause of wine induced asthma, direct evidence is limited. Two studies were undertaken to assess sulfite reactivity in wine sensitive asthmatics. The first study assessed sensitivity to sulfites in wine using a single dose sulfited wine challenge protocol followed by a double blind, placebo controlled challenge. In the second study a cumulative dose sulfited wine challenge protocol was employed to establish if wine sensitive asthmatics as a group have an increased sensitivity to sulfites.?METHODS—In study 1, 24 asthmatic patients with a strong history of wine induced asthma were screened. Subjects showing positive responses to single blind high sulfite (300 ppm) wine challenge were rechallenged on separate days in a double blind, placebo controlled fashion with wines of varying sulfite levels to characterise their responses to these drinks. In study 2, wine sensitive asthmatic patients (n=12) and control asthmatics (n=6) were challenged cumulatively with wine containing increasing concentrations of sulfite in order to characterise further their sensitivity to sulfites in wine.?RESULTS—Four of the 24 self-reporting wine sensitive asthmatic patients were found to respond to sulfite additives in wine when challenged in a single dose fashion (study 1). In the double blind dose-response study all four had a significant fall in forced expiratory volume in one second (FEV1) (>15% from baseline) following exposure to wine containing 300 ppm sulfite, but did not respond to wines containing 20, 75 or 150 ppm sulfite. Responses were maximal at 5 minutes (mean (SD) maximal decline in FEV1 28.7 (13)%) and took 15-60 minutes to return to baseline levels. In the cumulative dose-response study (study 2) no significant difference was observed in any of the lung function parameters measured (FEV1, peak expiratory flow (PEF), mid phase forced expiratory flow (FEF25-75)) between wine sensitive and normal asthmatic subjects.?CONCLUSIONS—Only a small number of wine sensitive asthmatic patients responded to a single dose challenge with sulfited wine under laboratory conditions. This may suggest that the role of sulfites and/or wine in triggering asthmatic responses has been overestimated. Alternatively, cofactors or other components in wine may play an important role in wine induced asthma. Cumulative sulfite dose challenges did not detect an increased sensitivity to sulfite in wine sensitive asthmatics and an alternative approach to identifying sulfite/wine sensitive asthma may be required.?? PMID:11562514

Vally, H; Thompson, P

2001-01-01

314

Linkage of High Rates of Sulfate Reduction in Yellowstone Hot Springs to Unique Sequence Types in the Dissimilatory Sulfate Respiration Pathway  

PubMed Central

Diversity, habitat range, and activities of sulfate-reducing prokaryotes within hot springs in Yellowstone National Park were characterized using endogenous activity measurements, molecular characterization, and enrichment. Five major phylogenetic groups were identified using PCR amplification of the dissimilatory sulfite reductase genes (dsrAB) from springs demonstrating significant sulfate reduction rates, including a warm, acidic (pH 2.5) stream and several nearly neutral hot springs with temperatures reaching 89°C. Three of these sequence groups were unrelated to named lineages, suggesting that the diversity and habitat range of sulfate-reducing prokaryotes exceeds that now represented in culture. PMID:12788778

Fishbain, Susan; Dillon, Jesse G.; Gough, Heidi L.; Stahl, David A.

2003-01-01

315

Curcumin, the main part of turmeric, prevents learning and memory changes induced by sodium metabisulfite, a preservative agent, in rats.  

PubMed

Sodium metabisulfite is used as a disinfectant, antioxidant, and preservative agent in the food, beverage, and drug industries. Neurons are highly sensitive to sulfite toxicity. Curcumin is the main part of turmeric and has neuroprotective effects on a variety of nervous system damages. The present study aimed to investigate the possible protective role of curcumin in learning and memory after exposure to sulfite in rats. The rats were divided into five groups receiving distilled water (solvent of the sulfite), olive oil (solvent of the curcumin), sodium metabisulfite (25 mg/kg/day), curcumin (100 mg/kg/day), and sulfite + curcumin. All the animals received daily gavages for 8 weeks. At the end of the 8(th) week, learning and memory were assessed in a partially-baited eight arm radial maze. The animals treated with sulfite showed fewer correct choices and more reference and working memory errors during the learning phase, at the end of the learning phase, and during the retention testing (p<0.001). The study results demonstrated that sulfite-exposure was associated with impaired learning and memory in rats. Adding curcumin to the rat nutrition plays a protective role in learning and memory after exposure to sulfite. PMID:23585719

Noorafshan, Ali; Asadi-Golshan, Reza; Karbalay-Doust, Saied; Abdollahifar, Mohammad Amin; Rashidiani-Rashidabadi, Ali

2013-03-01

316

A novel photochemical system of ferrous sulfite complex: kinetics and mechanisms of rapid decolorization of Acid Orange 7 in aqueous solutions.  

PubMed

We previously reported the decolorization of the azo dye Acid Orange 7 (AO7) by sulfate radical (SO4(-)) in the presence of iron(II) sulfite complex and oxygen under UV-vis irradiation (photo-iron(II) sulfite system). This system, however, achieves very limited mineralization of AO7 (in terms of total organic carbon (TOC) removal), which is not in accordance with literature reports on the oxidation of organic contaminants by SO4(-). In the present work, kinetics and products under irradiation of xenon lamp (350 W) were analyzed to reveal the reaction pathway of decolorization of AO7. Steady-state approximation (SSA) of SO4(-) radicals and apparent kinetics of AO7 were examined. The reaction between AO7 and SO4(-) was found to proceed in two steps, namely, electron transfer and SO4(-) addition. The second-order rate constant for the reaction between AO7 and SO4(-) was found to be 8.07 ± 1.07 × 10(9) M(-1) s(-1) by SSA and 6.80 ± 0.68 × 10(9) M(-1) s(-1) by competition kinetics method. The apparent kinetics of the decolorization of AO7 under irradiation closely fits the mechanism of radical chain reactions of various reactive sulfur species. By liquid chromatography coupled with mass spectrometry, we identified the sulfate adduct AO7-SO4 and confirmed the two-step reaction between AO7 and SO4(-). This stable sulfate adduct provides a good explanation of the poor TOC removal during decolorization of AO7 by the photo-iron(II) sulfite system. PMID:24704906

Zhou, Danna; Chen, Long; Zhang, Changbo; Yu, Yingtan; Zhang, Li; Wu, Feng

2014-06-15

317

Efficient synthesis of fatty monoglyceride sulfates from fatty acids and fatty acid methyl esters  

Microsoft Academic Search

An efficient high yield synthesis of fatty monoglyceride sulfates from fatty acids or fatty acid methyl esters, glycerine\\u000a and chlorosulfuric acid in chloroform using stoichiometric amounts of reagents was developed. Sodium coco monoglyceride sulfate\\u000a was prepared in 79% yield with 93% purity from coco fatty acids. Similarly, sodium palm kernel monoglyceride sulfate in 57%\\u000a yield and sodium palm monoglyceride sulfate

Fahim U. Ahmed

1990-01-01

318

Molecular analysis of the spatial distribution of sulfate-reducing bacteria in three eutrophicated wastewater stabilization ponds  

Microsoft Academic Search

The spatial distribution of sulfate-reducing bacteria (SRB) within three eutrophicated wastewater stabilization ponds (anaerobic,\\u000a facultative and maturation) was assessed by terminal restriction fragment (TRF) polymorphism targeting the dissimilatory (bi)\\u000a sulfite reductase (dsrAB) gene. High sulfate reducing diversity was confirmed through the 93 and 78 TRFs found using Sau3A1 and Taq ?1 restriction enzymes. Statistical analysis using Simpson (D) and Shannon

Abdelaziz Belila; Ahmed Ghrabi; Abdennaceur Hassen

319

Critical Comparison between Modified Monier-Williams and Electrochemical Methods to Determine Sulfite in Aqueous Solutions  

PubMed Central

In the present work, known concentration of sulfite aqueous solutions in the presence and absence of gallic acid was measured to corroborate the validity of modified Monier-Williams method. Free and bound-sulfite was estimated by differential pulse voltammetry. To our surprise, the modified Monier-Williams method (also known as aspiration method) showed to be very inaccurate for free-sulfite, although suitable for bound-sulfite determination. The differential pulse approach, using the standard addition method and a correction coefficient, proved to be swift, cheap, and very precise and accurate. PMID:22619610

Montes, C.; Vélez, J. H.; Ramírez, G.; Isaacs, M.; Arce, R.; Aguirre, M. J.

2012-01-01

320

Disturbance of brain energy and redox homeostasis provoked by sulfite and thiosulfate: potential pathomechanisms involved in the neuropathology of sulfite oxidase deficiency.  

PubMed

Sulfite oxidase (SO) deficiency is biochemically characterized by tissue accumulation and high urinary excretion of sulfite, thiosulfate and S-sulfocysteine. Affected patients present severe neurological symptoms and cortical atrophy, whose pathophysiology is still poorly established. Therefore, in the present work we investigated the in vitro effects of sulfite and thiosulfate on important parameters of energy metabolism in the brain of young rats. We verified that sulfite moderately inhibited the activity of complex IV, whereas thiosulfate did not alter any of the activities of the respiratory chain complexes. It was also found that sulfite and thiosulfate markedly reduced the activity of total creatine kinase (CK) and its mitochondrial and cytosolic isoforms, suggesting that these metabolites impair brain cellular energy buffering and transfer. In contrast, the activity of synaptic Na(+),K(+)-ATPase was not altered by sulfite or thiosulfate. We also observed that the inhibitory effect of sulfite and thiosulfate on CK activity was prevented by melatonin, reduced glutathione and the combination of both antioxidants, as well as by the nitric oxide synthase N(?)-nitro-l-arginine methyl ester, indicating the involvement of reactive oxygen and nitrogen species in these effects. Sulfite and thiosulfate also increased 2',7'-dichlorofluorescin oxidation and hydrogen peroxide production and decreased the activity of the redox sensor aconitase enzyme, reinforcing a role for oxidative damage in the effects elicited by these metabolites. It may be presumed that the disturbance of cellular energy and redox homeostasis provoked by sulfite and thiosulfate contributes to the neurological symptoms and abnormalities found in patients affected by SO deficiency. PMID:24035933

Grings, Mateus; Moura, Alana Pimentel; Parmeggiani, Belisa; Marcowich, Gustavo Flora; Amaral, Alexandre Umpierrez; de Souza Wyse, Angela Terezinha; Wajner, Moacir; Leipnitz, Guilhian

2013-12-01

321

Effects of ultrasound and sodium lauryl sulfate on the transdermal delivery of hydrophilic permeants: Comparative in vitro studies with full-thickness and split-thickness pig and human skin  

PubMed Central

The simultaneous application of ultrasound and the surfactant sodium lauryl sulfate (referred to as US/SLS) to skin enhances transdermal drug delivery (TDD) in a synergistic mechanical and chemical manner. Since full-thickness skin (FTS) and split-thickness skin (STS) differ in mechanical strength, US/SLS treatment may have different effects on their transdermal transport pathways. Therefore, we evaluated STS as an alternative to the well-established US/SLS-treated FTS model for TDD studies of hydrophilic permeants. We utilized the aqueous porous pathway model to compare the effects of US/SLS treatment on the skin permeability and the pore radius of pig and human FTS and STS over a range of skin electrical resistivity values. Our findings indicate that the US/SLS-treated pig skin models exhibit similar permeabilities and pore radii, but the human skin models do not. Furthermore, the US/SLS-enhanced delivery of gold nanoparticles and quantum dots (two model hydrophilic macromolecules) is greater through pig STS than through pig FTS, due to the presence of less dermis that acts as an artificial barrier to macromolecules. In spite of greater variability in correlations between STS permeability and resistivity, our findings strongly suggest the use of 700-?m-thick pig STS to investigate the in vitro US/SLS-enhanced delivery of hydrophilic macromolecules. PMID:20346994

Seto, Jennifer E.; Polat, Baris E.; Lopez, Renata F.V.; Blankschtein, Daniel; Langer, Robert

2010-01-01

322

Clinical Mycoplasma gallisepticum infection in multiplier breeder and meat turkeys caused by F strain: identification by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, restriction endonuclease analysis, and the polymerase chain reaction.  

PubMed

In February 1991, a flock of North Carolina multiplier breeder turkeys experienced respiratory signs, sinusitis, airsacculitis, and increased mortality. Mycoplasma gallisepticum (MG) was isolated, and appropriate control measures were initiated. Ultimately, this outbreak involved several breeder flocks of an integrated turkey production company before the last infected flock was identified in May 1991. During this time, MG was also isolated from a flock of commercial layer-type chickens raised as pullets in close proximity to the index turkey flock. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and restriction endonuclease analysis indicated that these isolates were identical to each other and to examples of the vaccinal F strain. Additionally, MG isolates from the affected turkey breeder and layer flocks were identified as MG F strain by use of an F strain-specific DNA probe and polymerase chain reaction. A separate outbreak of MG disease in several meat-turkey flocks of a Midwest producer/processor yielded isolates identified as F strain by the polymerase chain reaction. These studies demonstrated: 1) the utility of newer technologies for disease outbreak investigations; and 2) the potential of MG F strain to cause disease in breeder and meat turkeys under field conditions. PMID:8257382

Ley, D H; Avakian, A P; Berkhoff, J E

1993-01-01

323

Monotropein isolated from the roots of Morinda officinalis ameliorates proinflammatory mediators in RAW 264.7 macrophages and dextran sulfate sodium (DSS)-induced colitis via NF-?B inactivation.  

PubMed

We previously demonstrated that monotropein isolated from the roots of Morinda officinalis (Rubiaceae) has anti-inflammatory effects in vivo. In the present study, we investigated the molecular mechanisms underlying the anti-inflammatory effects of monotropein in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages and dextran sulfate sodium (DSS)-induced colitis mouse model. Monotropein was found to inhibit the expressions of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-? (TNF-?), and interleukin-1? (IL-1?) mRNA in LPS-induced RAW 264.7 macrophages. Treatment with monotropein decreased the DNA binding activity of nuclear factor-?B (NF-?B). Consistent with these findings, monotropein also suppressed phosphorylation and degradation of inhibitory ?B-? (I?B-?), and consequently the translocations of NF-?B. In the DSS-induced colitis model, monotropein reduced disease activity index (DAI), myeloperoxidase (MPO) activity, and inflammation-related protein expressions by suppressing NF-?B activation in colon mucosa. Taken together, these findings suggest that the anti-inflammatory effects of monotropein are mainly related to the inhibition of the expressions of inflammatory mediators via NF-?B inactivation, and support its possible therapeutic role in colitis. PMID:23261679

Shin, Ji-Sun; Yun, Kyung-Jin; Chung, Kyung-Sook; Seo, Kyeong-Hwa; Park, Hee-Juhn; Cho, Young-Wuk; Baek, Nam-In; Jang, Daesik; Lee, Kyung-Tae

2013-03-01

324

Effect of alloy composition on the sodium-sulfate induced hot corrosion attack of cast nickel-base superalloys at 900 C  

NASA Technical Reports Server (NTRS)

The effects of Cr, Al, Ti, Mo, Ta, Nb, and W content on the hot corrosion of Ni-base alloys were examined experimentally. The superalloys were tested for 300 1-hr cycles at 900 C in a Mach 0.3 burner rig flame containing 0.5 ppmw sodium. The data reveal that the best corrosion resistance is obtained when the Cr content is greater than 12 percent; however, good resistance is detected in some alloys with Cr content less than 10 percent provided that the Al content is less than 2.5 wt pct and the Ti content is less than 4 wt pct. It is observed that the influence of W, Ta, Mo, and Nb content on resistance is dependent on Al and Ti contents. The derivation of an equation for estimating hot corrosion attack as a function of alloy composition using multiple linear regression analysis is described. The applicability of the equation is tested using various data sets of alloys. It is noted that the equation can be used to explain the effects of alloy composition on attack rates.

Stearns, C. A.; Deadmore, D. L.; Barrett, C. A.

1987-01-01

325

Preparation and characterization of sodium dodecyl sulfate doped polypyrrole solid phase micro extraction fiber and its application to endocrine disruptor pesticide analysis.  

PubMed

A robust in house solid-phase micro extraction (SPME) surface has been developed for the headspace (HS)-SPME determination of endocrine disruptor pesticides, namely, Chlorpyrifos, Penconazole, Procymidone, Bromopropylate and Lambda-Cyhalothrin in wine sample by using sodium dodecylsulfate doped polypyrrole SPME fiber. Pyrrole monomer was electrochemically polymerized on a stainless steel wire in laboratory conditions in virtue of diminishing the cost and enhancing the analyte retention on its surface to exert better selectivity and hence the developed polymerized surface could offer to analyst to exploit it as a fiber in headspace SPME analysis. The parameters, mainly, adsorption temperature and time, desorption temperature, stirring rate and salt amount were optimized to be as 70°C and 45min, 200°C, 600rpm and 10gL(-1), respectively. Limit of detection was estimated in the range of 0.073-1.659ngmL(-1) for the pesticides studied. The developed method was applied in to red wine sample with acceptable recovery values (92-107%) which were obtained for these selected pesticides. PMID:23669608

Korba, Korcan; Pelit, Levent; Pelit, Füsun Okçu; Ozdokur, K Volkan; Erta?, Hasan; Ero?lu, Ahmet E; Erta?, F Nil

2013-06-15

326

A Continuous Spectrophotometric Assay for APS Reductase Activity with Sulfite-Selective Probes  

PubMed Central

Mycobacterium tuberculosis (Mtb) adenosine 5?-phosphosulfate (APS) reductase (EC number 1.8.4.10), (APR) catalyzes the first committed step in sulfate reduction for the biosynthesis of essential reduced sulfur-containing biomolecules, such as cysteine, and is essential for survival in the latent phase of TB infection. Despite the importance of APR to Mtb, and other bacterial pathogens, current assay methods depend on use of [35S]-labeled APS or shunt AMP to a coupled-enzyme system. Both methods are cumbersome and require the use of expensive reagents. Here we report the development of a continuous spectrophotometric method for measuring APR activity by using novel sulfite-selective colorimetric or “off-on” fluorescent levulinate-based probes. The APR activity can thus be followed by monitoring the increase in absorbance or fluorescence of the resulting phenolate product. Using this assay, we determined Michelis-Menten kinetic constants (Km, kcat, kcat/Km) and apparent inhibition constant (Ki) for adenosine 5?-diphosphate (ADP), which compared favorably to values obtained in the gold-standard radioactive assay. The newly developed assay is robust and easy to perform with a simple spectrophotometer. PMID:23711725

Paritala, Hanumantharao; Carroll, Kate S.

2013-01-01

327

Bone sialoprotein II synthesized by cultured osteoblasts contains tyrosine sulfate  

SciTech Connect

Isolated mouse osteoblasts that retain their osteogenic activity in culture were incubated with (35S) sulfate. Two radiolabeled proteins, in addition to proteoglycans, were extracted from the calcified matrix of osteoblast cultures. All the sulfate label in both proteins was in the form of tyrosine sulfate as assessed by amino acid analysis and thin layer chromatography following alkaline hydrolysis. The elution behavior on DEAE-Sephacel of the major sulfated protein and the apparent Mr on sodium dodecyl sulfate gels were characteristic of bone sialoprotein II extracted from rat. This protein was shown to cross-react with an antiserum raised against bovine bone sialoprotein II, indicating that bone sialoprotein II synthesized by cultured mouse osteoblasts is a tyrosine-sulfated protein. The minor sulfated protein was tentatively identified as bone sialoprotein I or osteopontin based on its elution properties on DEAE-Sephacel and anomalous behavior on sodium dodecyl sulfate gels similar to those reported for rat bone sialoprotein I.

Ecarot-Charrier, B.; Bouchard, F.; Delloye, C. (Shriners Hospital, Montreal, Quebec (Canada))

1989-11-25

328

Comparative study of sulfite pretreatments for robust enzymatic saccharification of corn cob residue  

PubMed Central

Background Corn cob residue (CCR) is a kind of waste lignocellulosic material with enormous potential for bioethanol production. The moderated sulphite processes were used to enhance the hydrophily of the material by sulfonation and hydrolysis. The composition, FT-IR spectra, and conductometric titrations of the pretreated materials were measured to characterize variations of the CCR in different sulfite pretreated environments. And the objective of this study is to compare the saccharification rate and yield of the samples caused by these variations. Results It was found that the lignin in the CCR (43.2%) had reduced to 37.8%, 38.0%, 35.9%, and 35.5% after the sulfite pretreatment in neutral, acidic, alkaline, and ethanol environments, respectively. The sulfite pretreatments enhanced the glucose yield of the CCR. Moreover, the ethanol sulfite sample had the highest glucose yield (81.2%, based on the cellulose in the treated sample) among the saccharification samples, which was over 10% higher than that of the raw material (70.6%). More sulfonic groups and weak acid groups were produced during the sulfite pretreatments. Meanwhile, the ethanol sulfite treated sample had the highest sulfonic group (0.103 mmol/g) and weak acid groups (1.85 mmol/g) in all sulfite treated samples. In FT-IR spectra, the variation of bands at 1168 and 1190 cm-1 confirmed lignin sulfonation during sulfite pretreatment. The disappearance of the band at 1458 cm-1 implied the methoxyl on lignin had been removed during the sulfite pretreatments. Conclusions It can be concluded that the lignin in the CCR can be degraded and sulfonated during the sulfite pretreatments. The pretreatments improve the hydrophility of the samples because of the increase in sulfonic group and weak acid groups, which enhances the glucose yield of the material. The ethanol sulfite pretreatment is the best method for lignin removal and with the highest glucose yield. PMID:23206858

2012-01-01

329

Oxygen isotopic fractionation during bacterial sulfate reduction  

NASA Astrophysics Data System (ADS)

Sulfur isotope fractionation during bacterial sulfate reduction (BSR) is understood to depend on a variety of environmental parameters, such as sulfate concentration, temperature, cell specific sulfate reduction rates, and the carbon substrate. What controls oxygen isotope fractionation during BSR is less well understood. Some studies have suggested that carbon substrate is important, whereas others concluded that there is a stoichiometric relationship between the fractionations of sulfur and oxygen during BSR. Studies of oxygen fractionation are complicated by isotopic equilibration between sulfur intermediates, particularly sulfite, and water. This process can modify the isotopic composition of the extracellular sulfate pool (?18OSO4 ). Given this, the challenge is to distinguish between this isotopic equilibration and fractionations linked to the kinetic effects of the intercellular enzymes and the incorporation of sulfate into the bacterial cell. The ?18OSO4 , in concert with the sulfur isotope composition of sulfate (?34SSO4), could be a powerful tool for understanding the pathways and environmental controls of BSR in natural systems. We will present ?18OSO4 data measured from batch culture growth of 14 different species of sulfate reducing bacteria for which sulfur isotope data were previously published. A general observation is that ?18OSO4 shows little isotopic change (<4‰) even when the ?34SSO4 varies by up to 30 to 50‰ over the course of the experiment. This disparity could reflect little to no kinetic effect during BSR and/or equilibration between sulfur intermediates and the isotopically light water (~-5‰) of the growth medium. Our present batch culture data do not allow us to convincingly isolate the magnitude and the controlling parameters of the kinetic isotope effect for oxygen. However, ongoing growth of mutant bacteria missing enzymes critical in the different steps of BSR may assist in this mission.

Balci, N.; Turchyn, A. V.; Lyons, T.; Bruchert, V.; Schrag, D. P.; Wall, J.

2006-12-01

330

Optimization of Sulfide/Sulfite Pretreatment of Lignocellulosic Biomass for Lactic Acid Production  

PubMed Central

Potential of sodium sulfide and sodium sulfite, in the presence of sodium hydroxide was investigated to pretreat the corncob (CC), bagasse (BG), water hyacinth and rice husk (RH) for maximum digestibility. Response Surface Methodology was employed for the optimization of pretreatment factors such as temperature, time and concentration of Na2S and Na2SO3, which had high coefficient of determination (R2) along with low probability value (P), indicating the reliable predictability of the model. At optimized conditions, Na2S and Na2SO3 remove up to 97% lignin, from WH and RH, along with removal of hemicellulose (up to 93%) during pretreatment providing maximum cellulose, while in BG and CC; 75.0% and 90.0% reduction in lignin and hemicellulose was observed. Saccharification efficiency of RH, WH, BG and CC after treatment with 1.0% Na2S at 130°C for 2.3–3.0 h was 79.40, 85.93, 87.70, and 88.43%, respectively. WH treated with Na2SO3 showed higher hydrolysis yield (86.34%) as compared to Na2S while other biomass substrates showed 2.0–3.0% less yield with Na2SO3. Resulting sugars were evaluated as substrate for lactic acid production, yielding 26.48, 25.36, 31.73, and 30.31 gL?1 of lactic acid with 76.0, 76.0, 86.0, and 83.0% conversion yield from CC, BG, WH, and RH hydrolyzate, respectively. PMID:24058918

Adnan, Ahmad; Qureshi, Fahim Ashraf

2013-01-01

331

The Impact of Simulated Sulfate Deposition on Peatland Testate Amoebae  

Microsoft Academic Search

Peatlands subjected to sulfate deposition have been shown to produce less methane, believed to be due to competitive exclusion\\u000a of methanogenic archaea by sulfate-reducing bacteria. Here, we address whether sulfate deposition produces impacts on a higher\\u000a microbial group, the testate amoebae. Sodium sulfate was applied to experimental plots on a Scottish peatland and samples\\u000a extracted after a period of more

Richard Payne; Vincent Gauci; Dan J. Charman

2010-01-01

332

Curcumin Can Prevent the Changes in Cerebellar Structure and Function Induced by Sodium Metabisulfite in Rat  

PubMed Central

Sulfites are used as anti-microbial and anti-oxidant agents in the food and pharmaceutical industries. Curcumin, a flavonoid, is an Asian spice that shows neuroprotective activities. The current study aimed to stereologically assess the rats' cerebellar cortex and rotarod performance following sulfite exposure and determine the possible neuroprotective potential of curcumin. The rats were divided into five groups: distilled water, olive oil, curcumin (100 mg/kg/day), sodium metabisulfite (25 mg/kg/day), and sodium metabisulfite+curcumin. At 56 days after treatment, rotarod performance was tested, and then the cerebellum was removed for stereological analysis. The study results revealed 31%, 36%, 19% and 24% decrease in the total volume of the cerebellum, cortex, the total number of the Purkinje cells and length of the nerve fibers in the cortex per Purkinje, respectively in the sodium metabisulfite-treated rats compared to the distilled water group (p<0.01). The pre-trained animals on the rotarod apparatus were tested first on the fixed speed rotarod protocol followed by the accelerating rotarod protocol two days later. The results showed a significant decrease in the latency to fall in both test in sulfite-treated rats. The sulfite effects on the structural parameters and rotarod performance were significantly protected by the concomitant curcumin treatment (p<0.001). Sulfite can induce structural and functional changes in the rats' cerebellum and concomitant curcumin prescription plays a neuroprotective role. PMID:24465141

Noorafshan, Ali; Rashidiani-Rashidabadi, Ali; Poostpasand, Aghdas; Abdollahifar, Mohammad-Amin; Asadi-Golshan, Reza

2013-01-01

333

Spectrophotometric Determination of Total Sulfite in White Wine Samples Using Crude Extracts from Flowers  

NASA Astrophysics Data System (ADS)

A didactic spectrophotometric method for determining the sulfite content in white wine samples is proposed. It is based upon a discoloring reaction between flower anthocyanins and the sulfite in basic media. Students' results obtained from iodometric data agreed well with results obtained by the proposed procedure. The use of natural dyes attracted students' interest, enhancing the learning process.

Flora Barbosa Soares, Márlon Herbert; Ramos, Luiz Antonio; Tadeu Gomes Cavalheiro, Éder

2002-09-01

334

OXIDATIVE DEGRADATION OF ORGANIC ACIDS CONJUGATED WITH SULFITE OXIDATION IN FLUE GAS DESULFURIZATION  

EPA Science Inventory

The report gives results of a study of organic acid degradation conjugated with sulfite oxidation under flue gas desulfurization (FGD) conditions. The oxidative degradation constant, k12, is defined as the ratio of organic acid degradation rate and sulfite oxidation rate times th...

335

Keratin degradation by dermatophytes relies on cysteine dioxygenase and a sulfite efflux pump.  

PubMed

Millions of people suffer from superficial infections caused by dermatophytes. Intriguingly, these filamentous fungi exclusively infect keratin-rich host structures such as hair, nails, and skin. Keratin is a hard, compact protein, and its utilization by dermatophytes for growth has long been discussed as a major virulence attribute. Here, we provide strong support for the hypothesis that keratin degradation is facilitated by the secretion of the reducing agent sulfite, which can cleave keratin-stabilizing cystine bonds. We discovered that sulfite is produced by dermatophytes from environmental cysteine, which at elevated concentrations is toxic for microbes and humans. We found that sulfite formation from cysteine relies on the key enzyme cysteine dioxygenase Cdo1. Sulfite secretion is supported by the sulfite efflux pump Ssu1. Targeted mutagenesis proved that dermatophyte mutants in either Cdo1 or Ssu1 were highly growth-sensitive to cysteine, and mutants in Ssu1 were specifically sensitive to sulfite. Most notably, dermatophyte mutants in Cdo1 and Ssu1 were specifically growth-defective on hair and nails. As keratin is rich in cysteine, our identified mechanism of cysteine conversion and sulfite efflux supports both cysteine and sulfite tolerance per se and progression of keratin degradation. These in vitro findings have implications for dermatophyte infection pathogenesis. PMID:23353986

Grumbt, Maria; Monod, Michel; Yamada, Tsuyoshi; Hertweck, Christian; Kunert, Jiri; Staib, Peter

2013-06-01

336

Characterization of a New Type of Dissimilatory Sulfite Reductase Present in Thermodesulfobacterium commune  

PubMed Central

A new type of dissimilatory bisulfite reductase, desulfofuscidin, was isolated from the nonsporeforming thermophilic sulfate-reducing microorganism Thermodesulfobacterium commune. The molecular weight of the enzyme was estimated at 167,000 by sedimentation equilibrium, and the protein was pure by both disc electrophoresis and ultracentrifugation. The bisulfite reductase was a tetramer and had two types of subunits with an ?2?2 structure and an individual molecular weight of 47,000. The enzyme exhibited absorption maxima at 576, 389, and 279 nm, with a weak band at 693 nm. Upon the addition of dithionite, the absorption maxima at 576 and 693 nm were weakened, and a new band appeared at 605 nm. The protein reacted with CO in the presence of dithionite to give a complex with absorption peaks at 593, 548, and 395 nm. The extinction coefficients of the purified enzyme at 576, 389, and 279 nm were 89,000, 310,000, and 663,000 M?1 cm?1, respectively. Siroheme was detected as the prosthetic group. The protein contains 20 to 21 nonheme iron atoms and 16 to 17 acid-labile sulfur groups per molecule. The data suggest the presence of four sirohemes and probably four (4Fe-4S) centers per molecule by comparison with desulfoviridin, the dissimilatory sulfite reductase from Desulfovibrio species. The protein contains 36 cysteine residues and is high in acidic and aromatic amino acids. The N-terminal amino acids of the ? and ? subunits were threonine and serine, respectively. With reduced methyl viologen as electron donor, the major product of sulfite reduction was trithionate, and the pH optimum for activity was 6.0. The enzyme was stable to 70°C and denatured rapidly above this temperature. The dependence of T. commune bisulfite reductase activity on temperature was linear between 35 and 65°C, and the Q10 values observed were above 3. The presence of this new type of dissimilatory bisulfite reductase in T. commune is discussed in terms of taxonomic significance. PMID:6826522

Hatchikian, E. C.; Zeikus, J. G.

1983-01-01

337

A new diketopyrrolopyrrole-based probe for sensitive and selective detection of sulfite in aqueous solution  

NASA Astrophysics Data System (ADS)

A new probe was synthesized by incorporating an ?,? -unsaturated ketone to a diketopyrrolopyrrole fluorophore. The probe had exhibited a selective and sensitive response to the sulfite against other thirteen anions and biothiols (Cys, Hcy and GSH), through the nucleophilic addition of sulfite to the alkene of probe with the detection limit of 0.1 ?M in HEPES (10 mM, pH 7.4) THF/H2O (1:1, v/v). Meanwhile, it could be easily observed that the probe for sulfite changed from pink to colorless by the naked eye, and from pink to blue under UV lamp after the sulfite was added for 20 min. The NMR and Mass spectral analysis demonstrated the expected addition of sulfite to the Cdbnd C bonds.

Yang, Xiaofeng; Cui, Yu; Li, Yexin; Zheng, Luyi; Xie, Lijun; Ning, Rui; Liu, Zheng; Lu, Junling; Zhang, Gege; Liu, Chunxiang; Zhang, Guangyou

2015-02-01

338

A real-time colorimetric and ratiometric fluorescent probe for sulfite.  

PubMed

A real-time colorimetric and ratiometric fluorescent probe based on modulating the intramolecular charge transfer (ICT) of the coumarin platform for selective detection of sulfite is presented. This reaction based probe utilized the Michael addition to the dicyano-vinyl group with the detection limit of 5.8 × 10(-5) M. The probe displayed a high selectivity for sulfite over other anions and reactive sulfur especially for biothiols including cysteine (Cys), homocysteine (Hcy) and glutathione (GSH), with about 100 nm blue shift and more than 230 times intensity ratios change of the emission spectrum. Meanwhile, it could be easily observed that the probe for sulfite changes from red to pale yellow by the naked eye, and from red to blue under UV lamp immediately after the sulfite is added. To the best of our knowledge, it is the fastest response probe for sulfite ever reported, which could give a colorimetric and ratiometric fluorescent response instantly. PMID:23563108

Wu, Ming-Yu; He, Ting; Li, Kun; Wu, Ming-Bo; Huang, Zheng; Yu, Xiao-Qi

2013-05-21

339

Magnesium sulfate.  

PubMed

Since the first American report on the use of magnesium sulfate tocolysis in 1977, its popularity as a tocolytic agent has increased progressively. Primarily because of its safety and familiarity, magnesium has become the primary tocolytic agent in the majority of U.S. centers. The exact mechanism of action is unknown, and long-term effects on neonates have not been studied. Although randomized studies show similar success compared to other tocolytic agents, no placebo-controlled study has shown neonatal improvement with magnesium sulfate tocolysis. This is similar to the studies of beta-sympathomimetic tocolytics and has led some authors (e.g., Higby) to suggest that safe dosages of magnesium sulfate are ineffective in preventing preterm birth and should not be used as a tocolytic agent. Although magnesium sulfate, like other tocolytics, has not fulfilled the initial promise of preventing preterm birth, it does appear if used correctly in a well identified population of patients to at least transiently inhibit preterm labor as well as other tocolytic agents with fewer side effects and fewer contraindications. PMID:8616968

Gordon, M C; Iams, J D

1995-12-01

340

SO 2 adsorption and thermal stability and reducibility of sulfates formed on the magnesium-aluminate spinel sulfur-transfer catalyst  

NASA Astrophysics Data System (ADS)

Magnesium-aluminate spinel used as a sulfur-transfer catalyst in the fluid catalytic cracking units for SO x emission control was prepared by the precipitation method. The crystalline structure, textural property, and surface dehydroxylation of the sample were characterized by thermogravimetry-derivative thermogravimetry (TG-DTG), differential thermal analysis (DTA), X-ray diffraction (XRD), liquid N 2 adsorption-desorption and infrared spectroscopy (IR) measurements. The behavior of SO 2 adsorption and oxidation on the surface of catalyst was evaluated with IR from 50°C to 600°C. Particularly, the thermal stability and H 2-reducibility of the formed sulfite or sulfate during SO 2 adsorption or oxidation were tested under various conditions. In the absence of oxygen in the feed mixture, weak physically adsorbed SO 2 species and surface sulfite were identified. In the case of SO 2 oxidative adsorption, both surface sulfate and bulk-like sulfate were formed. When the sulfated sample was reduced with hydrogen, the surface sulfite and sulfates were completely removed below 550°C in vacuum. The bulk-like sulfate, however, showed a high ability to resist H 2-reduction, which indicates that the reducibility of bulk-like sulfate formed on magnesium-aluminate spinel must be enhanced when it is used as a sulfur-transfer catalyst.

Wang, Jin-an; Li, Cheng-lie

2000-07-01

341

75 FR 56101 - Lauryl Sulfate Salts Registration Review Final Decision; Notice of Availability  

Federal Register 2010, 2011, 2012, 2013

...EPA-HQ-OPP-2009-0727; FRL-8839-6] Lauryl Sulfate Salts Registration Review Final Decision; Notice of...review decision for the pesticide, lauryl sulfate salts (also known as sodium lauryl salts), case 4061. Registration review is...

2010-09-15

342

Determination of the sensitising activity of the rubber contact sensitisers TMTD, ZDMC, MBT and DEA in a modified local lymph node assay and the effect of sodium dodecyl sulfate pretreatment on local lymph node responses.  

PubMed

A modified local lymph node assay (LLNA) was used to determine the sensitising activity of four chemicals used for the production of natural rubber latex products. Tetramethylthiuramdisulfide (TMTD), 2-mercaptobenzothiazole (MBT) and zincdimethyldithiocarbamate (ZDMC), three moderate human sensitisers, and diethylamine (DEA) a known human sensitiser, were epicutaneously administered on the ear and the proliferating activity in the draining (auricular) lymph node (LN) was determined by ex vivo (3)H-thymidine incorporation. Consistent results were obtained for TMTD and ZDMC with stimulation indices (SI) above 3, identifying these compounds as sensitiser, while for DEA and MBT inconsistent results were obtained. For all parameters determined such as LN weight, LN cell number, cell proliferation per 2 x 10(6) cells, and cell proliferation per LN statistical significant increases were observed. The SI, expressed as cellular proliferation per LN or per animal (left and right LN combined), was the most sensitive parameter with an optimum at day 5 after start of treatment.Furthermore, we investigated whether the use of sodium dodecyl sulfate (SDS) was able to enhance weak responses in the LLNA. SDS treatment with dosages of 10% and higher resulted in a SI above 3, while a dosage of 1% SDS showed no activity. Pretreatment with 1% SDS 1 h before application of the rubber chemicals enhanced the responses to these chemicals consistently, identifying also DEA and MBT as sensitisers. Our results indicate that SDS had synergistic activity on the LN responses of the administered rubber chemicals in the LLNA. For the moderately responding sensitisers TMTD and ZDMC both IFN-gamma and IL-4 production was observed. For the weakly responding sensitisers DEA and MBT both IFN-gamma and IL-4 cytokine production was only observed after pretreatment of the animals with 10% SDS. For 10% and 20% SDS, inducing approximately a SI of 20 in the LLNA, no induction of cytokines was observed. PMID:12062936

De Jong, Wim H; Tentij, Marlies; Spiekstra, Sander W; Vandebriel, Rob J; Van Loveren, Henk

2002-07-01

343

Binding of sodium dodecyl sulfate and hexaethylene glycol mono-n-dodecyl ether to the block copolymer L64: electromotive force, microcalorimetry, surface tension, and small angle neutron scattering investigations of mixed micelles and polymer/micellar surfactant complexes.  

PubMed

The interactions of sodium dodecyl sulfate (SDS) with the triblock copolymer L64 (EO13-PO30-EO13) and hexaethylene glycol mono-n-dodecyl ether (C12EO6) were studied using electromotive force, isothermal titration microcalorimetry, differential scanning microcalorimetry, and surface tension measurements. In certain regions of binding, mixed micelles are formed, and here we could evaluate an interaction parameter using regular solution theory. The mixed micelles of L64 with both SDS and C12EO6 exhibit synergy. When L64 is present in its nonassociated state, it forms polymer/micellar SDS complexes at SDS concentrations above the critical aggregation concentration (cac). The cac is well below the critical micellar concentration (cmc) of pure SDS, and a model suggesting how bound micelles are formed at the cac in the presence of a polymer is described. The interaction of nonassociated L64 with C12EO6 is a very rare example of strong binding between a nonionic surfactant and a nonionic polymer, and C12EO6/L64 mixed micelles are formed. We also carried out small angle neutron scattering measurement to determine the structure of the monomeric polymer/micellar SDS complex, as well as the mixed L64/C12EO6 aggregates. In these experiments, contrast matching was achieved by using the h and d forms of SDS, as well as C12EO6. During the early stages of the formation of polymer-bound SDS micelles, SDS aggregates with aggregation numbers of approximately 20 were found and such complexes contain 4-6 bound L64 monomers. The L64/C12EO6 data confirmed the existence of mixed micelles, and structural information involving the composition of the mixed micelle and the aggregation numbers were evaluated. PMID:16229545

Couderc-Azouani, S; Sidhu, J; Thurn, T; Xu, R; Bloor, D M; Penfold, J; Holzwarth, J F; Wyn-Jones, E

2005-10-25

344

Heat capacity and other thermodynamic properties of Na 2SO 4(aq) in hydrothermal solutions and the solubilities of sodium sulfate minerals in the system Na-Cl-SO 4-OH-H 2O to 300°C  

NASA Astrophysics Data System (ADS)

Heat capacities of Na 2SO 4(aq) solutions have been measured from 140°-300°C at 200 bars using a flowcalorimeter over the molality range of 0.05-1.5 mol·kg -1. Using the ion-interaction or virial coefficient approach developed by PITZER (1973, 1979, 1987) and coworkers, and approximating the pressure-dependencies of the various Na 2SO 4(aq) thermodynamic quantities with those of NaCl(aq) calculated from the equations of ROGERS and PITZER (1982), our measured heat capacities were combined with literature values on heat capacities, enthalpies, and osmotic coefficients at temperatures to 225°C and at pressures mostly at 1 bar or vapor-saturation pressure to yield a comprehensive set of equations for the thermodynamic properties of Na 2SO 4(aq) at temperatures 25°-300°C, pressure to at least 200 bars, and molalities to 3.0 mol·kg -1. Standard state chemical potentials and activity and osmotic coefficients of Na 2SO 4(aq) derived from our model, together with standard state properties of the solids available in the literature, permit the calculation of sodium sulfate solubilities in water and in electrolyte mixtures to 300°C. Good agreement between experimental and predicted solubilities in water indicate that the ion-interaction model can be used successfully to predict mineral-solution equilibria to 300°C without an explicit accounting for ion-pairs, and demonstrates that heat capacity measurements can be used to obtain reliable high-temperature and high-pressure activity properties of electrolyte solutions. The binary and ternary mixing parameters ? ü and ? ük are required by the ion-interaction model for calculations for multicomponent mixtures. It was found sufficient to adopt previously determined values for ? ü at 25°C without temperature dependence and, from the solubility data, to determine temperature-dependent ? ük functions.

Pabalan, Roberto T.; Pitzer, Kenneth S.

1988-10-01

345

Development and Comparison of SYBR Green Quantitative Real-time PCR Assays for Detection and Enumeration of Sulfate-reducing Bacteria in Stored Swine Manure  

Technology Transfer Automated Retrieval System (TEKTRAN)

A quantitative real-time polymerase chain reaction (PCR) assay for sulfate-reducing bacteria (SRB) was developed that targeted the dissimilatory sulfite reductase gene (dsrA). Degenerate primer sets were developed to detect three different groups of SRB in stored swine manure using a SYBR Green qua...

346

Vitrification of high sulfate wastes  

SciTech Connect

The US Department of Energy (DOE) through the Mixed Waste Integrated Program (MWIP) is investigating the application of vitrification technology to mixed wastes within the DOE system This work involves identifying waste streams, laboratory testing to identify glass formulations and characterize the vitrified product, and demonstration testing with the actual waste in a pilot-scale system. Part of this program is investigating process limits for various waste components, specifically those components that typically create problems for the application of vitrification, such as sulfate, chloride, and phosphate. This work describes results from vitrification testing for a high-sulfate waste, the 183-H Solar Evaporation Basin waste at Hanford. A low melting phosphate glass formulation has been developed for a waste stream high in sodium and sulfate. At melt temperatures in the range of 1,000 C to 1,200 C, sulfate in the waste is decomposed to gaseous oxides and driven off during melting, while the remainder of the oxides stay in the melt. Decomposition of the sulfates eliminates the processing problems typically encountered in vitrification of sulfate-containing wastes, resulting in separation of the sulfate from the remainder of the waste and allowing the sulfate to be collected in the off-gas system and treated as a secondary waste stream. Both the vitreous product and intentionally devitrified samples are durable when compared to reference glasses by TCLP and DI water leach tests. Simple, short tests to evaluate the compatibility of the glasses with potential melter materials found minimal corrosion with most materials.

Merrill, R.A.; Whittington, K.F.; Peters, R.D.

1994-09-01

347

In vitro evaluation of the potential role of sulfite radical in morphine-associated histamine release  

PubMed Central

Background Intravenous morphine use is associated with elevated histamine release leading to bronchoconstriction, edema and hemodynamic instability in some patients. This study evaluated the possibility that sulfite, which is present as a preservative in many morphine preparations, might contribute to histamine release in vitro. Results The human mast cell line, HMC-1, was exposed to various morphine concentrations, in the absence of sulfite, under cell culture conditions. Clinically attained concentrations of morphine (0.018?g/ml and 0.45?g/ml) did not cause increased histamine release from mast cells. There was a significant increase in histamine release when the morphine concentration was increased by 1184-fold (668?g/ml morphine). Histamine release from mast cells exposed to morphine and/or sulfite required the presence of prostaglandin H synthetase. Histamine release in experiments using sulfite-containing morphine solutions was not statistically different from that observed in morphine-only solutions. Conclusion Sulfite in sulfite-containing morphine solutions, at concentrations seen clinically, is not responsible for histamine release in in vitro experiments of the human mast cell line, HMC-1. This does not preclude the fact that sulfite may lead to elevation of histamine levels in vivo. PMID:15469613

Gordon, Emma M; Myers, Carolyn; Blumer, Jeffrey

2004-01-01

348

Desulfitibacter alkalitolerans gen. nov., sp. nov., an anaerobic, alkalitolerant, sulfite-reducing bacterium isolated from a district heating plant.  

PubMed

A novel alkalitolerant, anaerobic bacterium, designated strain sk.kt5(T), was isolated from a metal coupon retrieved from a corrosion-monitoring reactor of a Danish district heating plant (Skanderborg, Jutland). The cells of strain sk.kt5(T) were motile, rod-shaped (0.4-0.6 x 2.5-9.6 microm), stained Gram-positive and formed endospores. Strain sk.kt5(T) grew at pH 7.6-10.5 (with optimum growth at pH 8.0-9.5), at temperatures in the range 23-44 degrees C (with optimum growth at 35-37 degrees C), at NaCl concentrations in the range 0-5 % (w/v) (with optimum growth at 0-0.5 %) and required yeast extract for growth. Only a limited number of substrates were utilized as electron donors, including betaine, formate, lactate, methanol, choline and pyruvate. Elemental sulfur, sulfite, thiosulfate, nitrate and nitrite, but not sulfate or Fe(III) citrate, were used as electron acceptors. The G+C content of the DNA was 41.6 mol%. Phylogenetic analyses of the sequence data for the dsrAB genes [encoding the major subunits of dissimilatory (bi)sulfite reductase] and the 16S rRNA gene placed strain sk.kt5(T) within a novel lineage in the class Clostridia of the phylum Firmicutes. Taken together, the physiological and genotypic data suggest that strain sk.kt5(T) represents a novel species within a novel genus, for which the name Desulfitibacter alkalitolerans gen. nov., sp. nov. is proposed. The type strain of Desulfitibacter alkalitolerans is sk.kt5(T) (=JCM 12761(T)=DSM 16504(T)). PMID:17158984

Nielsen, Marie Bank; Kjeldsen, Kasper Urup; Ingvorsen, Kjeld

2006-12-01

349

[Determination of fibrinogen concentration in blood plasma by the sulfite precipitation method].  

PubMed

Two methods using thrombine and sulfite were compared for estimation of fibrinogen concentration in blood plasma. Both methods produced the same results in estimation of fibrinogen in donor blood plasma. If blood plasma contained high amount of products of fibrinogen and/or fibrin degradation, the efficiency of thrombin method was decreased; on the other hand, final concentration of sulfite did not precipitate fragment D of fibrinogen from human blood plasma. Presence of heparin did not influence on the sulfite method but the polysaccharide might interfere in the thrombin method. Some experiments require to use both these methods for evaluation of fibrinogen in blood plasma. PMID:425377

Tsariuk, L A; Rybachuk, V N; Shevchenko, L I; Tolstykh, V M

1979-01-01

350

Theoretical study on the reactivity of sulfate species with hydrocarbons  

USGS Publications Warehouse

The abiotic, thermochemically controlled reduction of sulfate to hydrogen sulfide coupled with the oxidation of hydrocarbons, is termed thermochemical sulfate reduction (TSR), and is an important alteration process that affects petroleum accumulations in nature. Although TSR is commonly observed in high-temperature carbonate reservoirs, it has proven difficult to simulate in the laboratory under conditions resembling nature. The present study was designed to evaluate the relative reactivities of various sulfate species in order to provide greater insight into the mechanism of TSR and potentially to fill the gap between laboratory experimental data and geological observations. Accordingly, quantum mechanics density functional theory (DFT) was used to determine the activation energy required to reach a potential transition state for various aqueous systems involving simple hydrocarbons and different sulfate species. The entire reaction process that results in the reduction of sulfate to sulfide is far too complex to be modeled entirely; therefore, we examined what is believed to be the rate limiting step, namely, the reduction of sulfate S(VI) to sulfite S(IV). The results of the study show that water-solvated sulfate anions SO42 - are very stable due to their symmetrical molecular structure and spherical electronic distributions. Consequently, in the absence of catalysis, the reactivity of SO42 - is expected to be extremely low. However, both the protonation of sulfate to form bisulfate anions (HSO4-) and the formation of metal-sulfate contact ion-pairs could effectively destabilize the sulfate molecular structure, thereby making it more reactive. Previous reports of experimental simulations of TSR generally have involved the use of acidic solutions that contain elevated concentrations of HSO4- relative to SO42 -. However, in formation waters typically encountered in petroleum reservoirs, the concentration of HSO4- is likely to be significantly lower than the levels used in the laboratory, with most of the dissolved sulfate occurring as SO42 -, aqueous calcium sulfate ([CaSO4](aq)), and aqueous magnesium sulfate ([MgSO4](aq)). Our calculations indicate that TSR reactions that occur in natural environments are most likely to involve bisulfate ions (HSO4-) and/or magnesium sulfate contact ion-pairs ([MgSO4]CIP) rather than 'free' sulfate ions (SO42 -) or solvated sulfate ion-pairs, and that water chemistry likely plays a significant role in controlling the rate of TSR. ?? 2008 Elsevier Ltd. All rights reserved.

Ma, Q.; Ellis, G.S.; Amrani, A.; Zhang, T.; Tang, Y.

2008-01-01

351

Theoretical study on the reactivity of sulfate species with hydrocarbons  

NASA Astrophysics Data System (ADS)

The abiotic, thermochemically controlled reduction of sulfate to hydrogen sulfide coupled with the oxidation of hydrocarbons, is termed thermochemical sulfate reduction (TSR), and is an important alteration process that affects petroleum accumulations in nature. Although TSR is commonly observed in high-temperature carbonate reservoirs, it has proven difficult to simulate in the laboratory under conditions resembling nature. The present study was designed to evaluate the relative reactivities of various sulfate species in order to provide greater insight into the mechanism of TSR and potentially to fill the gap between laboratory experimental data and geological observations. Accordingly, quantum mechanics density functional theory (DFT) was used to determine the activation energy required to reach a potential transition state for various aqueous systems involving simple hydrocarbons and different sulfate species. The entire reaction process that results in the reduction of sulfate to sulfide is far too complex to be modeled entirely; therefore, we examined what is believed to be the rate limiting step, namely, the reduction of sulfate S(VI) to sulfite S(IV). The results of the study show that water-solvated sulfate anions SO42- are very stable due to their symmetrical molecular structure and spherical electronic distributions. Consequently, in the absence of catalysis, the reactivity of SO42- is expected to be extremely low. However, both the protonation of sulfate to form bisulfate anions ( HSO4-) and the formation of metal-sulfate contact ion-pairs could effectively destabilize the sulfate molecular structure, thereby making it more reactive. Previous reports of experimental simulations of TSR generally have involved the use of acidic solutions that contain elevated concentrations of HSO4- relative to SO42-. However, in formation waters typically encountered in petroleum reservoirs, the concentration of HSO4- is likely to be significantly lower than the levels used in the laboratory, with most of the dissolved sulfate occurring as SO42-, aqueous calcium sulfate ([CaSO 4] (aq)), and aqueous magnesium sulfate ([MgSO 4] (aq)). Our calculations indicate that TSR reactions that occur in natural environments are most likely to involve bisulfate ions ( HSO4-) and/or magnesium sulfate contact ion-pairs ([MgSO 4] CIP) rather than 'free' sulfate ions ( SO42-) or solvated sulfate ion-pairs, and that water chemistry likely plays a significant role in controlling the rate of TSR.

Ma, Qisheng; Ellis, Geoffrey S.; Amrani, Alon; Zhang, Tongwei; Tang, Yongchun

2008-09-01

352

Removal of Sulfate Ion From AN-107 by Evaporation  

SciTech Connect

Hanford low-activity waste solutions contain sulfate, which can cause accelerated corrosion of the vitrification melter and unacceptable operating conditions. A method is needed to selectively separate sulfate from the waste. An experiment was conducted to evaluate evaporation for removing sulfate ion from Tank AN-107 low-activity waste. Two evaporation steps were performed. In the first step, the volume was reduced by 55% while in the second step, the liquid volume was reduced another 22%. Analysis of the solids precipitated during these evaporations revealed that large amounts of sodium nitrate and nitrite co-precipitated with sodium sulfate. Many other waste components precipitated as well. It can be concluded that sulfate removal by precipitation is not selective, and thus, evaporation is not a viable option for removing sulfate from the AN-107 liquid.

GJ Lumetta; GS Klinger; DE Kurath; RL Sell; LP Darnell; LR Greenwood; CZ Soderquist; MJ Steele; MW Urie; JJ Wagner

2000-08-02

353

DsrB gene-based DGGE for community and diversity surveys of sulfate-reducing bacteria  

Microsoft Academic Search

A denaturing gradient gel electrophoresis (DGGE) method was developed to assess the diversity of dsrB (dissimilatory sulfite reductase ?-subunit)-genes in sulfate-reducing communities. For this purpose a PCR primer pair was optimized for the amplification of a ?350 bp dsrB gene fragment that after DGGE gel electrophoresis enabled us to discriminate between dsrB genes of different SRB-subgroups,-genera and -species. The dsrB-DGGE

Joke Geets; Brigitte Borremans; Ludo Diels; Dirk Springael; Jaco Vangronsveld; Daniel van der Lelie; Karolien Vanbroekhoven

2006-01-01

354

Development of an amperometric sulfite biosensor based on SO(x)/PBNPs/PPY modified ITO electrode.  

PubMed

A sulfite oxidase (SO(x)) (EC 1.8.3.1) purified from Syzygium cumini leaves was immobilized onto prussian blue nanoparticles/polypyrrole composite (PBNPs/PPY) electrodeposited onto the surface of indium tin oxide (ITO) electrode. An amperometric sulfite biosensor was fabricated using SO(x)/PBNPs/PPY/ITO electrode as working electrode, Ag/AgCl as standard and Pt wire as auxiliary electrode connected through a potentiostat. The working electrode was characterized by Fourier transform infrared (FTIR) spectroscopy, cyclic voltammetry (CV), scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS) before and after immobilization of SO(x). The biosensor showed optimum response within 2s, when operated at 20 mV s?¹ in 0.1M Tris-HCl buffer, pH 8.5 and at 35 °C. Linear range and minimum detection limit were 0.5-1000 ?M and 0.12 ?M (S/N=3) respectively. There was good correlation (r=0.99) between red wine samples sulfite value by standard DTNB method and the present method. The sensor was evaluated with 97% recovery of added sulfite in red wine samples and 2.2% and 4.3% within and between batch coefficients of variation respectively. The sensor was employed for determination of sulfite level in red and white wine samples. The enzyme electrode was used 200 times over a period of 3 months when stored at 4 °C. PMID:22705572

Rawal, Rachna; Pundir, C S

2012-11-01

355

ELECTRON DETACHMENT DISSOCIATION OF SYNTHETIC HEPARAN SULFATE GLYCOSAMINOGLYCAN TETRASACCHARIDES VARYING IN DEGREE OF SULFATION AND HEXURONIC ACID STEREOCHEMISTRY  

PubMed Central

Glycosaminoglycan (GAG) carbohydrates provide a challenging analytical target for structural determination due to their polydisperse nature, non-template biosynthesis, and labile sulfate modifications. The resultant structures, although heterogeneous, contain domains which indicate a sulfation pattern or code that correlates to specific function. Mass spectrometry, in particular electron detachment dissociation Fourier transform ion cyclotron resonance (EDD FT-ICR MS), provides a highly sensitive platform for GAG structural analysis by providing cross-ring cleavages for sulfation location and product ions specific to hexuronic acid stereochemistry. To investigate the effect of sulfation pattern and variations in stereochemistry on EDD spectra, a series of synthetic heparan sulfate (HS) tetrasaccharides are examined. Whereas previous studies have focused on lowly sulfated compounds (0.5–1 sulfate groups per disaccharide), the current work extends the application of EDD to more highly sulfated tetrasaccharides (1–2 sulfate groups per disaccharide) and presents the first EDD of a tetrasaccharide containing a sulfated hexuronic acid. For these more highly sulfated HS oligomers, alternative strategies are shown to be effective for extracting full structural details. These strategies inlcude sodium cation replacement of protons, for determining the sites of sulfation, and desulfation of the oligosaccharides for the generation of product ions for assigning uronic acid stereochemistry. PMID:23230388

Leach, Franklin E.; Arungundram, Sailaja; Al-Mafraji, Kanar; Venot, Andre; Boons, Geert-Jan; Amster, I. Jonathan

2012-01-01

356

Sulfate resistance of high calcium fly ash concrete  

NASA Astrophysics Data System (ADS)

Sulfate attack is one of the mechanisms which can cause deterioration of concrete. In general, Class C fly ash mixtures are reported to provide poor sulfate resistance. Fly ashes, mainly those belonging to the Class C, were tested as per the ASTM C 1012 procedure to evaluate chemical sulfate resistance. Overall the Class C fly ashes showed poor resistance in the sulfate environment. Different strategies were used in this research work to improve the sulfate resistance of Class C fly ash mixes. The study revealed that some of the strategies such as use of low W/CM (water to cementing materials by mass ratio), silica fume or ultra fine fly ash, high volumes of fly ash and, ternary or quaternary mixes with suitable supplementary cementing materials, can successfully improve the sulfate resistance of the Class C fly ash mixes. Combined sulfate attack, involving physical and chemical action, was studied using sodium sulfate and calcium sulfate solutions. The specimens were subjected to wetting-drying cycles and temperature changes. These conditions were found to accelerate the rate of degradation of concrete placed in a sodium sulfate environment. W/CM was found to be the main governing factor in providing sulfate resistance to mixes. Calcium sulfate did not reveal damage as a result of mainly physical action. Characterization of the selected fly ashes was undertaken by using SEM, XRD and the Rietveld analysis techniques, to determine the relation between the composition of fly ashes and resistance to sulfate attack. The chemical composition of glass represented on the ternary diagram was the main factor which had a significant influence on the sulfate resistance of fly ash mixtures. Mixes prepared with fly ashes containing significant amounts of vulnerable crystalline phases offered poor sulfate resistance. Comparatively, fly ash mixes containing inert crystalline phases such as quartz, mullite and hematite offered good sulfate resistance. The analysis of hydrated lime-fly ash pastes confirmed that fly ash mortar or concrete mixes forming more monosulfate than ettringite before exposure to sulfates would offer poor sulfate resistance and vice versa. During quantitative Rietveld analysis carried out for determining ettringite, monosulfate and gypsum formed in the fly ash pastes, it was observed that fly ash mixtures showing more ettringite after exposures to sulfates, give poor sulfate resistance. A good relationship between the amounts of ettringite formed and expansions of mortar specimens in the ASTM C 1012 test was found.

Dhole, Rajaram

357

[Determination of sulfite in flue gas desulfurization with seawater by ion chromatography].  

PubMed

The technology for flue gas desulfurization (FGD) with seawater is widely adopted by coal-fired power plants in coastal areas. SO2 in the flue gas is absorbed by alkaline seawater and transfered in aqueous phase as sulfite (SO3(2-)), and most SO3(2-) is transformed to sulfate (SO4(2-)) after an aeration process. The remaining SO3(2-) in the seawater discharged to sea area may be harmful to marine organism because of its biological toxicity, thus it is necessary to determine the concentration of SO3(2-) in the seawater for desulfurization. In this study, the method of determination of SO3(2-) in the seawater by ion chromatography was investigated. The separation was achieved on an IonPac AS14A column with 14 mmol/L NaOH-12 mmol/L Na2 CO3 solution as the mobile phase at a flow rate of 1.2 mL/min, and the detection was performed by a pulsed amperometric detector. Formaldehyde was added as a protective agent when sampling because the SO3(2-) is easy to be oxidized. To avoid the formation of Mg (OH)2 in the mobile phase with high pH value which might block the column, the Mg(2+) in seawater was precipitated by NaOH solution (pH 12.0) before sample determination. The method showed good linearity within the range of 0-100 mg/L with an average recovery of 116.8%. The method detection limit (MDL) reached as low as 0.05 mg/L. The relative standard deviations (RSD) for seawater matrix samples spiked at levels of 7.5, 25.0 and 75.0 mg/L were 2.1% 3.1% and 4.0% (n = 9) , respectively. The method has been applied for the determination of SO3(2-) in flue gas desulfurization seawater with the advantages of being fast, sensitive and selective. PMID:20352939

Yin, Liqian; Yuan, Dongxing; Guo, Juan; Liu, Xiyao

2009-11-01

358

21 CFR 73.85 - Caramel.  

Code of Federal Regulations, 2010 CFR

...hydroxide U.S.P. Potassium hydroxide. Sodium hydroxide. (iii) Salts: Ammonium, sodium, or potassium carbonate, bicarbonate, phosphate (including dibasic phosphate and monobasic phosphate), sulfate, and sulfite. (3) Polyglycerol...

2010-04-01

359

Revisiting Modes of energy generation in sulfate reducing bacteria  

SciTech Connect

Sulfate reducing bacteria (SRB) play an important role in global sulfur and carbon cycling through their ability to completely mineralize organic matter while respiring sulfate to hydrogen sulfide. They are ubiquitous in anaerobic environments and have the ability to reduce toxic metals like Cr(VI) and U(VI). While SRB have been studied for over three decades, bioenergetic modes of this group of microbes are poorly understood. Desulfovibrio vulgaris strain Hildenborough (DvH) has served as a model SRB over the last decade with the accumulation of transcriptomic, proteomic and metabolic data under a wide variety of stressors. To further investigate the three hypothesized modes of energy generation in this anaerobe we conducted a systematic study involving multiple electron donor and acceptor combinations for growth. DvH was grown at 37oC in a defined medium with (a) lactate + thiosulfate, (b) lactate + sulfite (c) lactate + sulfate, (d) pyruvate + sulfate, (e) H2 + acetate + sulfate, (f) formate + acetate + sulfate, g) formate + sulfate and (h) pyruvate fermentation. Cells were harvested at mid-log phase of growth for all conditions for transcriptomics, when the optical density at 600nm was in the range 0.42-0.5. Initial results indicate that cells grown on lactate do not appear to significantly differentiate their gene expression profiles when presented with different electron acceptors. These profiles however differ significantly from those observed during growth with other electron donors such as H2 and formate, as well as during fermentative growth. Together the gene expression changes in the presence of different electron donors provide insights into the ability of DvH to differentially reduce metals such as Cr(VI). Here we present revised modes of energy generation in DvH in light of this new transcriptomic evidence.

Joachimiak, Marcin; Chakraborty, Romy; Zhou, Aifen; Fortney, Julian; Geller, Jil; Wall, Judy; Zhou, Jizhong; Arkin, Adam; Hazen, Terry; Keasling, Jay; Chhabra, Swapnil

2010-05-17

360

Effects of Sulfite on Metabolism in Isolated Mesophyll Cells from Papaver somniferum 1  

PubMed Central

Exposure (30 minutes) of leaf-free mesophyll cells from the C-3 plant, Papaver somniferum, to concentrations of sulfite (SO2 + HSO3? + SO3?) up to 20 millimolar stimulated the rate of CO2 incorporation as much as 30%. The sulfite rapidly affects the metabolism of newly incorporated CO2. Ammonia incorporation into glutamine and subsequent transamination reactions were stimulated during the short term exposure periods while glycolate metabolism apparently was inhibited by bisulfite at two points in the pathway. The results further indicate that glycolate is the major precursor of glycine in these cells. Prolonged periods of exposure (24 hours) to sulfite had somewhat different effects on carbon metabolism: the high concentrations (10 to 20 millimolar) severely inhibited all aspects of cellular metabolism while lower concentrations (1 millimolar) appeared to inhibit ammonia incorporation but stimulated synthesis of sucrose and starch. PMID:16660487

Paul, John S.; Bassham, James A.

1978-01-01

361

Dissolution rate of limestone for wet flue gas desulfurization in the presence of sulfite.  

PubMed

Limestone dissolution rate was measured by a pH-stat method with CO(2) sparging and dissolved sulfite. The dissolution rate of limestone under these conditions was found to be controlled by mass transfer and surface kinetics. As can be seen from the results, in the presence of sulfite, limestone dissolution rate increases with increasing stirring speed, reaction temperature and CO(2) partial pressure. The crystallinity of limestone has a great impact on the dissolution rate: The lower the value of the crystallinity of limestone is, the higher the dissolution rate is. The presence of sulfite promotes the dissolution rate when pH value is below 5.5 but inhibits it when pH value is above 5.5. PMID:19359093

Xiang, Gao; Rui-tang, Guo; Hong-lei, Ding; Zhong-yang, Luo; Ke-fa, Cen

2009-09-15

362

Synthesis of cyclic sulfites from epoxides and sulfur dioxide with silica-immobilized homogeneous catalysts.  

PubMed

Quaternary ammonium- and amino-functionalized silica catalysts have been prepared for the selective synthesis of cyclic sulfites from epoxides and sulfur dioxide, demonstrating the effects of immobilizing the homogeneous catalysts on silica. The cycloaddition of sulfur dioxide to various epoxides was conducted under solvent-free conditions at 100 °C. The quaternary ammonium- and amino-functionalized silica catalysts produced cyclic sulfites in high yields (79-96 %) that are comparable to those produced by the homogeneous catalysts. The functionalized silica catalysts could be separated from the product solution by filtration, thereby avoiding the catalytic decomposition of the cyclic sulfite products upon distillation of the product solution. Heterogenization of a homogeneous catalyst by immobilization can, therefore, improve the efficiency of the purification of crude reaction products. Despite a decrease in catalytic activity after each recycling step, the heterogeneous pyridine-functionalized silica catalyst provided high yields after as many as five recycling processes. PMID:22135049

Takenaka, Yasumasa; Kiyosu, Takahiro; Mori, Goro; Choi, Jun-Chul; Fukaya, Norihisa; Sakakura, Toshiyasu; Yasuda, Hiroyuki

2012-01-01

363

BUFFER ADDITIVES FOR LIME/LIMESTONE SLURRY SCRUBBING: SULFITE OXIDATION WITH ENHANCED OXYGEN ABSORPTION CATALYZED BY TRANSITION METALS  

EPA Science Inventory

The report gives results of a study of sulfite oxidation, involving the measurement of the rate of enhanced oxygen absorption across an unbroken interface into solution containing sulfite (2-100 mM) and catalyst (0.01-100 mM) at pH 4-6 and 50 C. Fe, Mn, Co, Cu and Cr ions were po...

364

Sulfite analysis of fruits and vegetables by high-performance liquid chromatography (HPLC) with ultraviolet spectrophotometric detection  

Technology Transfer Automated Retrieval System (TEKTRAN)

Free and total sulfite were analyzed in acidified vegetable products, instant mashed potatoes and dried apples. Sulfite was separated by HPLC and quantified with a UV/VIS detector. Good resolution from components of food samples was achieved by varying the acid concentration of the eluant solution...

365

Dietary Sodium  

MedlinePLUS

Table salt is made up of the elements sodium and chlorine - the technical name for salt is sodium chloride. Your body needs some sodium to work properly. ... to healthy eating is choosing foods low in salt and sodium. Doctors recommend you eat less than ...

366

An electrochemical sulfite biosensor based on gold coated magnetic nanoparticles modified gold electrode.  

PubMed

A sulfite oxidase (SO(X)) (EC 1.8.3.1) purified from Syzygium cumini leaves was immobilized onto carboxylated gold coated magnetic nanoparticles (Fe(3)O(4)@GNPs) electrodeposited onto the surface of a gold (Au) electrode through N-ethyl-N'-(3-dimethylaminopropyl) carbodiimide (EDC)-N-hydroxy succinimide (NHS) chemistry. An amperometric sulfite biosensor was fabricated using SO(X)/Fe(3)O(4)@GNPs/Au electrode as working electrode, Ag/AgCl as standard and Pt wire as auxiliary electrode. The working electrode was characterized by Fourier Transform Infrared (FTIR) Spectroscopy, Cyclic Voltammetry (CV), Scanning Electron Microscopy (SEM) and Electrochemical Impedance Spectroscopy (EIS) before and after immobilization of SO(X). The biosensor showed optimum response within 2s when operated at 0.2V (vs. Ag/AgCl) in 0.1 M Tris-HCl buffer, pH 8.5 and at 35 °C. Linear range and detection limit were 0.50-1000 ?M and 0.15 ?M (S/N=3) respectively. Biosensor was evaluated with 96.46% recovery of added sulfite in red wine and 1.7% and 3.3% within and between batch coefficients of variation respectively. Biosensor measured sulfite level in red and white wines. There was good correlation (r=0.99) between red wines sulfite value by standard DTNB (5,5'-dithio-bis-(2-nitrobenzoic acid)) method and the present method. Enzyme electrode was used 300 times over a period of 4 months, when stored at 4 °C. Biosensor has advantages over earlier biosensors that it has excellent electrocatalysis towards sulfite, lower detection limit, higher storage stability and no interference by ascorbate, cysteine, fructose and ethanol. PMID:22035973

Rawal, Rachna; Chawla, Sheetal; Pundir, Chandra Shekhar

2012-01-15

367

Desulfohalobium utahense sp. nov., a moderately halophilic, sulfate-reducing bacterium isolated from Great Salt Lake.  

PubMed

A novel moderately halophilic, sulfate-reducing bacterium, strain EtOH3(T), was isolated from anoxic hypersaline (270 g NaCl l(-1)) sediment of the northern arm of the Great Salt Lake, Utah, USA. Cells of strain EtOH3(T) were oval to rod-shaped, non-motile, non-sporulating and stained Gram-negative. The strain required sodium and magnesium ions for growth and grew at salinities of up to 240 g NaCl l(-1) and 121 g MgCl(2).6H(2)O l(-1). The optimum NaCl concentration was 80-100 g l(-1). Strain EtOH3(T) grew at temperatures ranging from 15 to 44 degrees Celsius (optimum 37 degrees Celsius). The pH range for growth was 6.5-8.3 (optimum around pH 6.8). Only sulfate and thiosulfate served as electron acceptors for a broad range of electron donors including various short-chain fatty acids and primary (C(1-5)) alcohols, amino acids, H(2)/acetate and H(2)/yeast extract. The G+C content of the genomic DNA was 51.4 mol%. Phylogenetic analysis of dsrAB [genes encoding the major subunits of dissimilatory (bi)sulfite reductase] and 16S rRNA gene sequence data placed strain EtOH3(T) within the deltaproteobacterial family Desulfohalobiaceae. Strain EtOH3(T) shared 76 and 91 % dsrAB and 16S rRNA gene sequence similarity, respectively, with the type strain of the phylogenetically most closely related species with a validly published name, Desulfohalobium retbaense DSM 5692(T). High 16S rRNA gene sequence similarity ( approximately 97 %) was shared with the recently described strain 'Desulfovermiculus halophilus' VKM B-2364. Strain EtOH3(T), however, clearly differed from this strain in both genomic G+C content and in several of its phenotypic properties. On the basis of phenotypic and genotypic characteristics, the novel species Desulfohalobium utahense sp. nov. is proposed, with strain EtOH3(T) (=VKM B-2384(T)=DSM 17720(T)) as the type strain. PMID:16957100

Jakobsen, Trine Fredlund; Kjeldsen, Kasper Urup; Ingvorsen, Kjeld

2006-09-01

368

Determination of oversulfated chondroitin sulfate and dermatan sulfate impurities in heparin by capillary electrophoresis  

Microsoft Academic Search

Recently, oversulfated chondroitin sulfate (OSCS) present in certain lots of heparin was identified as the toxic contaminant responsible for severe side effects following intravenous heparin administration. The United States Pharmacopeia (USP) and European Pharmacopeia (Eur.Ph.) announced an immediate revision of their monographs for heparin sodium by adding two US Food and Drugs Administration-recommended tests for OSCS based on nuclear magnetic

Govert W. Somsen; Yvonne H. Tak; Javier Sastre Toraño; Peter M. J. M. Jongen; Gerhardus J. de Jong

2009-01-01

369

Exchangeable oxygens in the vicinity of the molybdenum center of the high-pH form of sulfite oxidase and sulfite dehydrogenase†  

PubMed Central

The electron spin echo envelope modulation (ESEEM) investigation of the high-pH (hpH) form of sulfite oxidase (SO) and sulfite dehydrogenase (SDH) prepared in buffer enriched with H2 17O reveals the presence of three types of exchangeable oxygen atoms at the molybdenum center. Two of these oxygen atoms belong to the equatorial OH ligand and the axial oxo ligand, and are characterized by 17O hyperfine interaction (hfi) constants of about 37 MHz and 6 MHz, respectively. The third oxygen has an isotropic hfi constant of 3–4 MHz and likely belongs to a hydroxyl moiety hydrogen-bonded to the equatorial OH ligand. This exchangeable oxygen atom is not observed in the ESEEM spectra of the Y236F mutant of SDH, where the active site tyrosine has been replaced by phenylalanine. PMID:19639147

Klein, Eric L.; Ganyushin, Dmitry; Johnson-Winters, Kayunta; Neese, Frank; Kappler, Ulrike; Enemark, John H.

2009-01-01

370

[Plant sulfate assimilation and regulation of the activity of related enzymes under cadmium stress].  

PubMed

The complexation and sequestration of heavy metal ions (e.g. Cd) by the cysteine-rich polypeptides known as phytochelatins (PC) are thought to confer heavy metal hyperaccumulation and tolerance in some plant species. PC is synthesized enzymatically from glutathione. The tripeptide glutathione is a product of primary sulfur metabolism. A variety of enzymes or proteins are involved in sulfur assimilation including sulfate transporters (STs), ATP sulfurylase (ATPS), APS reductase (APSR), sulfite reductase (SiR), glutathione synthetase (GS) and phytochelatin synthesis (PCS). These enzymes or proteins are upstream-regulated by Cd at either the metabolic or the genetic level under metal stress. Increasing evidence shows that enhancement of sulfate uptake and reduction occurs with the production of PC in plants under heavy metal stress. In this article, the key aspects of our recent understanding of regulatory mechanisms involved in the relation between the sulfate assimilation and phytochelatin synthesis are described. PMID:16477125

Sun, Xue-Mei; Yang, Zhi-Min

2006-02-01

371

Increased sulfate uptake by E. coli overexpressing the SLC26-related SulP protein Rv1739c from Mycobacterium tuberculosis.  

PubMed

Growth and virulence of mycobacteria requires sulfur uptake. The Mycobacterium tuberculosis genome contains, in addition to the ABC sulfate permease cysTWA, three SLC26-related SulP genes of unknown function. We report that induction of Rv1739c expression in E. coli increased bacterial uptake of sulfate, but not Cl(-), formate, or oxalate. Uptake was time-dependent, maximal at pH 6.0, and exhibited a K(1/2) for sulfate of 4.0 muM. Na(+)-independent sulfate uptake was not reduced by bicarbonate, nitrate, or phosphate, but was inhibited by sulfite, selenate, thiosulfate, N-ethylmaleimide and carbonyl cyanide 3-chloro-phenylhydrazone. Sulfate uptake was also increased by overexpression of the Rv1739c transmembrane domain, but not of the cytoplasmic C-terminal STAS domain. Mutation to serine of the three cysteine residues of Rv1739c did not affect magnitude, pH-dependence, or pharmacology of sulfate uptake. Expression of Rv1739c in a M. bovis BCG strain lacking the ABC sulfate permease subunit CysA could not complement sulfate auxotrophy. Moreover, inducible expression of Rv1739c in an E. coli strain lacking CysA did not increase sulfate uptake by intact cells. Our data show that facilitation of bacterial sulfate uptake by Rv1739c requires CysA and its associated sulfate permease activity, and suggest that Rv1739c may be a CysTWA-dependent sulfate transporter. PMID:18255326

Zolotarev, Alexander S; Unnikrishnan, Meera; Shmukler, Boris E; Clark, Jeffrey S; Vandorpe, David H; Grigorieff, Nikolaus; Rubin, Eric J; Alper, Seth L

2008-03-01

372

Increased sulfate uptake by E. coli overexpressing the SLC26-related SulP protein Rv1739c from Mycobacterium tuberculosis  

PubMed Central

Growth and virulence of mycobacteria requires sulfur uptake. The Mycobacterium tuberculosis genome contains, in addition to the ABC sulfate permease cysTWA, three SLC26-related SulP genes of unknown function. We report that induction of Rv1739c expression in E. coli increased bacterial uptake of sulfate, but not Cl?, formate, or oxalate. Uptake was time-dependent, maximal at pH 6.0, and exhibited a K1/2 for sulfate of 4.0 ?M. Na+-independent sulfate uptake was not reduced by bicarbonate, nitrate, or phosphate, but was inhibited by sulfite, selenate, thiosulfate, N-ethylmaleimide and carbonyl cyanide 3-chloro-phenylhydrazone. Sulfate uptake was also increased by overexpression of the Rv1739c transmembrane domain, but not of the cytoplasmic C-terminal STAS domain. Mutation to serine of the three cysteine residues of Rv1739c did not affect magnitude, pH-dependence, or pharmacology of sulfate uptake. Expression of Rv1739c in a M. bovis BCG strain lacking the ABC sulfate permease subunit CysA could not complement sulfate auxotrophy. Moreover, inducible expression of Rv1739c in an E. coli strain lacking CysA did not increase sulfate uptake by intact cells. Our data show that facilitation of bacterial sulfate uptake by Rv1739c requires CysA and its associated sulfate permease activity, and suggest that Rv1739c may be a CysTWA-dependent sulfate transporter. PMID:18255326

Zolotarev, Alexander S.; Unnikrishnan, Meera; Shmukler, Boris E.; Clark, Jeffrey S.; Vandorpe, David H.; Grigorieff, Nikolaus; Rubin, Eric J.; Alper, Seth L.

2009-01-01

373

The role of sulfates on antifreeze protein activity.  

PubMed

In the present study, we have investigated the effect of sodium sulfate (Na2SO4) buffer on the antifreeze activity of DAFP-1, the primary AFP in the hemolymph of the beetle Dendroides canadensis. In contrast to previous studies, we found evidence that sodium sulfate does not suppress antifreeze activity of DAFP-1. Terahertz absorption spectroscopy (THz) studies were combined with molecular dynamics (MD) simulations to investigate the change in collective hydrogen bond dynamics in the vicinity of the AFP upon addition of sodium sulfate. The MD simulations revealed that the gradient of H-bond dynamics toward the ice-binding site is even more pronounced when adding sodium sulfate: The cosolute dramatically slows the hydrogen bond dynamics on the ice-binding plane of DAFP-1, whereas it has a more modest effect in the vicinity of other parts of the protein. These theoretical predictions are in agreement with the experimentally observed increase in THz absorption for solvated DAFP-1 upon addition of sodium sulfate. These studies support our previously postulated mechanism for AF activity, with a preferred ice binding by threonine on nanoice crystals which is supported by a long-range effect on hydrogen bond dynamics. PMID:24821472

Meister, Konrad; Duman, John G; Xu, Yao; DeVries, Arthur L; Leitner, David M; Havenith, Martina

2014-07-17

374

Ultrafiltration of sulfite liquors for separation of lignosulfonates removed from water by coagulation  

Microsoft Academic Search

This paper attempts to select an ultrafilter retaining lignosulfonate (LS) fractions precipitated by coagulants and to study the relationships of their concentration and efficiency of removal from water by coagulants. The material studied - sulfite liquor from the Syas' pulp and paper combine - was fractionated with the use of ''Vladipor'' cellulose acetate ultrafiltration membranes of various pore sizes. Data

Yu. M. Medvedev; M. I. Medvedev; E. A. Tsapyuk

1986-01-01

375

Survey of sulfites in wine and various Turkish food and food products intended for export, 2007-2010.  

PubMed

Surveys were carried out between 2007 and 2010 to determine the total levels of sulfites in 1245 samples of wines, dried apricots, dried vegetables, nuts, juices and purees, frozen foods and cereals containing dried fruit supplied by food inspectors and by food producers for testing or for export certification. Sulfite analysis of wine was carried out using the Ripper method with an LOQ of 5 mg l(-1) and for dried and other foods the Monier-Williams distillation procedure was employed with an LOQ of 10 mg kg(-1). In the survey all wines contained measurable sulfites, but with the exception of one sample of white wine they were otherwise below Turkish Food Codex limits of 160 mg kg(-1) for red wine, 210 mg kg(-1) to white wine and 235 mg kg(-1) for sparkling wine. None of the cereal products, frozen foods, juices or purees contained sulfites above 10 mg kg(-1). However, all dried apricot samples contained significant levels of sulfite with around 40% having levels exceeding the Turkish limit of 2000 mg kg(-1). Significant levels of sulfite were found in other samples of dried fruit with even a fruit and nut bar containing 1395 mg kg(-1) of sulfite, suggesting the dried fruit ingredients contained levels above regulatory limits. PMID:24786011

Ulca, P; Öztürk, Y; Senyuva, H Z

2011-01-01

376

Sodium Test  

MedlinePLUS

... sodium levels? 1. What is the recommended dietary salt intake? The Food and Nutrition Board recommends a ... of sodium are often processed food to which salt is added during preparation, such as cheeses, soups, ...

377

Preparation of carboxymethyl cellulose sulfates and its application as anticoagulant and wound dressing.  

PubMed

Tissue engineering is aiming to build an artificial environment or biological scaffold material that imitates the living environment of cells in the body. In this work, carboxymethyl cellulose sulfates were prepared by reacting carboxymethyl cellulose with N(SO3Na)3 which was synthesized by sodium bisulfite and sodium nitrite in aqueous solution. The reaction conditions affected the degree of substitution (DS) were measured by the barium sulfate nephelometry method. And the anticoagulant activity of carboxymethyl cellulose sulfates with different DS, concentration and molecular weights were investigated by the activated partial thromboplastin time (APTT), thrombin time (TT) and prothrombin time (PT). In addition, the effect of carboxymethyl cellulose sulfates on wound healing had been evaluated by the rate of wound healing and the histological examinations. The results indicated that the introduction of sulfate groups into the carboxymethyl cellulose sulfates improved its anticoagulant activity, and the wound dressings treated with carboxymethyl cellulose sulfates obviously promoted wound healing. PMID:24582936

Fan, Lihong; Zhou, Xiaoyu; Wu, Penghui; Xie, Weiguo; Zheng, Hua; Tan, Wang; Liu, Shuhua; Li, Qingyuan

2014-05-01

378

Studies on sulfate attack: Mechanisms, test methods, and modeling  

NASA Astrophysics Data System (ADS)

The objective of this research study was to investigate various issues pertaining to the mechanism, testing methods, and modeling of sulfate attack in concrete. The study was divided into the following segments: (1) effect of gypsum formation on the expansion of mortars, (2) attack by the magnesium ion, (3) sulfate attack in the presence of chloride ions---differentiating seawater and groundwater attack, (4) use of admixtures to mitigate sulfate attack---entrained air, sodium citrate, silica fume, and metakaolin, (5) effects of temperature and concentration of the attack solution, (6) development of new test methods using concrete specimens, and (7) modeling of the sulfate attack phenomenon. Mortar specimens using portland cement (PC) and tricalcium silicate (C 3S), with or without mineral admixtures, were prepared and immersed in different sulfate solutions. In addition to this, portland cement concrete specimens were also prepared and subjected to complete and partial immersion in sulfate solutions. Physical measurements, chemical analyses and microstructural studies were performed periodically on the specimens. Gypsum formation was seen to cause expansion of the C3S mortar specimens. Statistical analyses of the data also indicated that the quantity of gypsum was the most significant factor controlling the expansion of mortar bars. The attack by magnesium ion was found to drive the reaction towards the formation of brucite. Decalcification of the C-S-H and its subsequent conversion to the non-cementitious M-S-H was identified as the mechanism of destruction in magnesium sulfate attack. Mineral admixtures were beneficial in combating sodium sulfate attack, while reducing the resistance to magnesium sulfate attack. Air entrainment did not change the measured physical properties, but reduced the visible distress of the mortars. Sodium citrate caused a substantial reduction in the rate of damage of the mortars due to its retarding effect. Temperature and concentration of the solution were seen to change the rate and mechanism of the attack in both sodium and magnesium sulfate solutions. The test results from these experiments were used to generate models for prediction of physical properties such as expansion and mass change, which could be used either for service life predictions, or for designing more reliable laboratory tests. Lastly, mechanisms for the attack by sodium and magnesium sulfate were proposed, based on the observations in the various studies. These mechanisms were able to simplify the understanding of the sulfate attack phenomenon.

Santhanam, Manu

379

Chemiluminescence analysis of menadione sodium bisulfite and analgin in pharmaceutical preparations and biological fluids.  

PubMed

A novel chemiluminescence (CL) flow system for two sulfite-containing drugs, namely, menadione sodium bisulfite (MSB) and analgin is described. It is based on the weak chemiluminescence induced by the oxidation of sulfite group in drugs with dissolved oxygen in the presence of acidic Rh6G. Tween 80 surfactant micelles showed a strong enhancement effect on this weak chemiluminescence. For MSB analysis, online conversion of MSB in alkaline medium into sodium bisulfite was necessary, whereas analgin could be determined directly. The proposed method allowed the measurement of 0.05-50 microg/ml(-1) MSB and 0.05-10 microg/ml(-1) analgin. The limits of detection (3sigma) were 0.01 microg/ml(-1) MSB and 0.003 microg/ml(-1) analgin. The method was applied satisfactorily to pharmaceutical preparations as well as biological fluids. PMID:10701947

Huang, Y; Zhang, C; Zhang, X; Zhang, Z

1999-12-01

380

Phytoextraction potential of wild type and 35S-gshI transgenic poplar trees (Populus x Canescens) for environmental pollutants herbicide paraquat, salt sodium, zinc sulfate and nitric oxide in vitro.  

PubMed

Phytoextraction potentials of two transgenic (TR) poplar (Populus x canescens) clones TRggs11 and TRlgl6 were compared with that of wild-type (WT) following exposure to paraquat, zinc sulfate, common salt and nitric oxide (NO), using a leaf-disc system incubated for 21 days on EDTA-containing nutritive WPM media in vitro. Glutathione (GSH) contents of leaf discs of TRlgl6 and TRggs11 showed increments to 296% and 190%, respectively, compared with WT. NO exposure led to a twofold GSH content in TRlgl6, which was coupled with a significantly increased sulfate uptake when exposed to 10(-3) M ZnSO4. The highest mineral contents of Na, Zn, Mn, Cu, and Mo was observed in the TRggs11 clone. Salt-induced activity of catalase enzyme increased in both TR clones significantly compared with WT under NaCl (0.75% and 1.5%) exposure. The in silico sequence analyses of gsh1 genes revealed that P. x canadensis and Salix sachalinensis show the closest sequence similarity to that of P. x canescens, which predicted an active GSH production with high phytoextraction potentials of these species with indication for their use where P. x canescens can not be grown. PMID:24912238

Gyulai, G; Bittsánszky, A; Szabó, Z; Waters, L; Gullner, G; Kampfl, G; Heltai, G; Komíves, T

2014-01-01

381

Glycosaminoglycan Sulfation Requirements for Respiratory Syncytial Virus Infection  

Microsoft Academic Search

Glycosaminoglycans (GAGs) on the surface of cultured cells are important in the first step of efficient respiratory syncytial virus (RSV) infection. We evaluated the importance of sulfation, the major biosynthetic modification of GAGs, using an improved recombinant green fluorescent protein-expressing RSV (rgRSV) to assay infection. Pretreatment of HEp-2 cells with 50 mM sodium chlorate, a selective inhibitor of sulfation, for

LOUAY K. HALLAK; DOROTHE SPILLMANN; PETER L. COLLINS; MARK E. PEEPLES

2000-01-01

382

Sulfate-Reducing Bacterium with Unusual Morphology and Pigment Content  

PubMed Central

A dissimilatory sulfate-reducing bacterium was isolated which differed in morphology and pigment content from previously described species. The organism was mesophilic, obligately anaerobic, gram-negative, nonsporulating, long, and slender with one polar flagellum. Whole cells fluoresced red at neutral pH when excited with light at 365 nm owing to the presence of a pink pigment. Desulfoviridin was present. Reduced minus oxidized spectra of whole cells showed peaks in the position of a c-type cytochrome characteristic of Desulfovibrio species and peaks at about 629 and 603 nm. CO difference spectra showed the presence of a CO-binding pigment with a peak at 593 nm. Lactate and pyruvate supported growth in the presence of sulfate but not in its absence. Sulfate, sulfite, and thiosulfate served as electron acceptors for growth. Hydrogenase was present. The deoxyribonucleic acid had a buoyant density of 1.722 g/cm3 and a guanosine plus cystosine molar percentage of total bases calculated by two different methods of 61.2 or 63.2. Images PMID:4929856

Jones, H. E.

1971-01-01

383

Inhibition of sulfate-reducing and methanogenic activities of anaerobic sewer biofilms by ferric iron dosing.  

PubMed

Ferric iron is commonly used for sulfide precipitation in sewers, thus achieving corrosion and odour control. Its impact on the activities of sulfate-reducing bacteria and methanogens in anaerobic sewer biofilms is investigated in this study. Two lab-scale rising main sewer systems fed with real sewage were operated for 8 months. One received Fe(3+) dosage (experimental system) and the other was used as a control. In addition to precipitating sulfide from bulk water, Fe(3+) dosage was found to significantly inhibit sulfate reduction and methane production by sewer biofilms. The experimental reactor discharged an effluent containing a higher concentration of sulfate and a lower concentration of methane in comparison with the reference reactor. Batch experiments showed that the addition of ferric ions reduced the sulfate reduction and methane production rates of the sewer biofilms by 60% and 80%, respectively. The batch experiments further showed that Fe(3+) dosage changed the final products of sulfate reduction with sulfide accounting for only 54% of the sulfate reduced. The other products could not be confirmed, but were not dissolved inorganic sulfur species such as sulfite or thiosulfate. The results suggest the addition of Fe(3+) at upstream locations would minimize the ferric salts required for achieving the same level of sulfide removal. Fe(3+) dosing could also substantially reduce the formation of methane, a potent greenhouse gas, in sewers. PMID:19576610

Zhang, Lishan; Keller, Jürg; Yuan, Zhiguo

2009-09-01

384

Bicarbonate sulfate exchange in canalicular rat liver plasma membrane vesicles  

SciTech Connect

The mechanism(s) and driving forces for biliary excretion of sulfate were investigated in canalicular rat liver plasma membrane vesicles (cLPM). Incubation of cLPM vesicles in the presence of an inside-to-outside (in, out) bicarbonate gradient but not pH or out-to-in sodium gradients, stimulated sulfate uptake 10-fold compared with the absence of bicarbonate and approximately 2-fold above sulfate equilibrium (overshoot). Initial rates of this bicarbonate gradient-driven ({sup 35}S)-sulfate uptake were saturable with increasing concentrations of sulfate and could be inhibited by probenecid, N-(4-azido-2-nitrophenyl)-2-aminoethylsulfonate, acetazolamide, furosemide, 4-acetamideo-4{prime}-isothiocyanostilbene-2,2{prime}-disulfonic acid, and 4,4{prime}-diisothiocyanostilbene-2,2{prime}-disulfonic acid (IC{sub 50}, {approximately}40 {mu}M). Cisinhibition of initial bicarbonate gradient-stimulated sulfate uptake and transstimulation of sulfate uptake in the absence of bicarbonate were observed with sulfate, thiosulfate, and oxalate but not with chloride, nitrate, phosphate, acetate, lactate, glutamate, aspartate, cholate, taurocholate, dehydrocholate, taurodehydrocholate, and reduced or oxidized glutathione. These findings indicate the presence of a sulfate (oxalate)-bicarbonate anion exchange system in canalicular rat liver plasma membranes. These findings support the concept that bicarbonate-sensitive transport system might play an important role in bile acid-independent canalicular bile formation.

Meier, P.J.; Valantinas, J.; Hugentobler, G.; Rahm, I. (University Hospital, Zurich (Switzerland))

1987-10-01

385

Isolation and characterization of a mesophilic heavy-metals-tolerant sulfate-reducing bacterium Desulfomicrobium sp. from an enrichment culture using phosphogypsum as a sulfate source.  

PubMed

A sulfate-reducing bacterium, was isolated from a 6 month trained enrichment culture in an anaerobic media containing phosphogypsum as a sulfate source, and, designated strain SA2. Cells of strain SA2 were rod-shaped, did not form spores and stained Gram-negative. Phylogenetic analysis of the 16S rRNA gene sequence of the isolate revealed that it was related to members of the genus Desulfomicrobium (average sequence similarity of 98%) with Desulfomicrobium baculatum being the most closely related (sequence similarity of 99%). Strain SA2 used thiosulfate, sulfate, sulfite and elemental sulfur as electron acceptors and produced sulfide. Strain SA2 reduced sulfate contained in 1-20g/L phosphogypsum to sulfide with reduction of sulfate contained in 2g/L phosphogypsum being the optimum concentration. Strain SA2 grew with metalloid, halogenated and non-metal ions present in phosphogypsum and with added high concentrations of heavy metals (125ppm Zn and 100ppm Ni, W, Li and Al). The relative order for the inhibitory metal concentrations, based on the IC(50) values, was Cu, Te>Cd>Fe, Co, Mn>F, Se>Ni, Al, Li>Zn. PMID:16979290

Azabou, Samia; Mechichi, Tahar; Patel, Bharat K C; Sayadi, Sami

2007-02-01

386

Oxidative degradation of organic acid conjugated with sulfite oxidation in flue gas desulfurization: products, kinetics and mechanism  

Microsoft Academic Search

Organic acid degradation conjugated with sulfite oxidation has been studied under flue gas desulfurization (FGD) conditions. The oxidative degradation constant kââ is defined as the ratio of organic acid degradation rate and sulfite oxidation rate times the ratio of the concentration of dissolved S(IV) and organic acid. It is not significantly affected by pH or dissolved oxygen in the absence

Y. Joseph Lee; Gary T. Rochelle

1987-01-01

387

Sulfation of Aegle marmelos gum: synthesis, physico-chemical and functional characterization.  

PubMed

The present investigation was aimed at optimizing the conditions for preparing sulfated derivative of gum obtained from partially ripe fruits of Aegle marmelos. Elemental analysis, FTIR-ATR and NMR studies confirmed successful sulfation. The ratio of chlorosulfonic acid to pyridine exerted maximum influence on the degree of substitution followed by reaction temperature and reaction time. The sulfated derivative showed higher swelling in both acidic and alkaline pH as compared to unmodified gum. It also possessed higher negative zeta potential, higher viscosity, work of shear, firmness, consistency, cohesiveness and index of viscosity as compared to both unmodified gum as well as sodium alginate. Sulfated derivative was superior to unmodified gum and sodium alginate in terms of antimicrobial and anticoagulant activity. The sulfated sample appears to be a potential substitute over the unmodified gum sample and sodium alginate for modulating physicochemical properties of food and drug release dosage forms. PMID:23399204

Jindal, Manish; Rana, Vikas; Kumar, Vineet; Singh, Ram S; Kennedy, John F; Tiwary, Ashok K

2013-02-15

388

Roles of Heparan Sulfate Sulfation in Dentinogenesis*  

PubMed Central

Cell surface heparan sulfate (HS) is an essential regulator of cell signaling and development. HS traps signaling molecules, like Wnt in the glycosaminoglycan side chains of HS proteoglycans (HSPGs), and regulates their functions. Endosulfatases Sulf1 and Sulf2 are secreted at the cell surface to selectively remove 6-O-sulfate groups from HSPGs, thereby modifying the affinity of cell surface HSPGs for its ligands. This study provides molecular evidence for the functional roles of HSPG sulfation and desulfation in dentinogenesis. We show that odontogenic cells are highly sulfated on the cell surface and become desulfated during their differentiation to odontoblasts, which produce tooth dentin. Sulf1/Sulf2 double null mutant mice exhibit a thin dentin matrix and short roots combined with reduced expression of dentin sialophosphoprotein (Dspp) mRNA, encoding a dentin-specific extracellular matrix precursor protein, whereas single Sulf mutants do not show such defective phenotypes. In odontoblast cell lines, Dspp mRNA expression is potentiated by the activation of the Wnt canonical signaling pathway. In addition, pharmacological interference with HS sulfation promotes Dspp mRNA expression through activation of Wnt signaling. On the contrary, the silencing of Sulf suppresses the Wnt signaling pathway and subsequently Dspp mRNA expression. We also show that Wnt10a protein binds to cell surface HSPGs in odontoblasts, and interference with HS sulfation decreases the binding affinity of Wnt10a for HSPGs, which facilitates the binding of Wnt10a to its receptor and potentiates the Wnt signaling pathway, thereby up-regulating Dspp mRNA expression. These results demonstrate that Sulf-mediated desulfation of cellular HSPGs is an important modification that is critical for the activation of the Wnt signaling in odontoblasts and for production of the dentin matrix. PMID:22351753

Hayano, Satoru; Kurosaka, Hiroshi; Yanagita, Takeshi; Kalus, Ina; Milz, Fabian; Ishihara, Yoshihito; Islam, Md. Nurul; Kawanabe, Noriaki; Saito, Masahiro; Kamioka, Hiroshi; Adachi, Taiji; Dierks, Thomas; Yamashiro, Takashi

2012-01-01

389

Evolution and Ecology of Microbes Dissimilating Sulfur Compounds: Insights from Siroheme Sulfite Reductases  

Microsoft Academic Search

Sulfur microorganisms have been thriving on Earth since the dawn of life and are still of central importance for the functioning\\u000a of modern ecosystems. Here, we summarize the current perception of the evolution of dissimilatory siroheme sulfite reductases\\u000a (DSRs), antique key enzymes in the energy metabolism of sulfur microbes. We further give recent examples of the diversity\\u000a and ecology of

Alexander Loy; Stephan Duller; Michael Wagner

390

Combined S-33 and O-18 Isotope Tracing of Intracellular Sulfur Metabolism during Microbial Sulfate Reduction  

NASA Astrophysics Data System (ADS)

Microbial sulfate reduction is a key player in the global carbon cycle, oxidizing nearly 50% of organic matter in marine sediments. The biochemical pathway of microbial sulfate reduction fractionates sulfur and oxygen isotopes and these fractionations can be used to reconstruct S cycling in sediments. Sulfur isotope fractionation during microbial sulfate reduction, which partitions lighter sulfur (32S) into sulfide and heavier sulfur (33S and 34S) into the residual sulfate, can be as high as 72o for 34S/32S. The availability and type of organic substrate control the magnitude of sulfur isotope fractionation by influencing the fluxes of and the transfer of electrons to different S species. The partitioning of oxygen in sulfate during microbial sulfate reduction appears to be strongly influenced by the oxygen isotopic composition of water in which the bacteria grow, but its magnitude also seems to correlate with the magnitude of 34S/32S isotope fractionation. In addition, the fractionation of 33S/32S is thought to reflect the reversibility of some intercellular fluxes. We wanted to investigate whether the 18O/16O, 34S/32S and 33S/32S isotope fractionations in sulfate are controlled by the same intracellular processes and conditions. This was done by investigating the combined sulfur and oxygen isotope partitioning by a marine Desulfovibrio sp. grown in pure culture on different organic substrates and in water with different isotopic composition of oxygen. The isotope fractionations of oxygen and sulfur correlated with the cell specific sulfate reduction rates (csSRR), where slower rates yielded higher sulfur fractionation (as high as 60) and higher oxygen isotope fractionation. The trends in 33S/32S and 34S/32S with the changing csSRR was similar to the trends in 18O/16O with the csSRR, suggesting that the same intercellular pathways controlled both oxygen and sulfur isotope signatures during microbial sulfate reduction. The use of water with different isotopic composition of oxygen showed that the kinetic isotopic fractionation was negligible and that ?18O in sulfate should be 22.5o higher than ?18O in water (at 22° C). This relationship indicates that more intracellular sulfite may be oxidized back to sulfate when the flux of electrons from the electron donor to sulfite is low, allowing isotopic exchange of oxygen between sulfite and water. The use of our experimental results as constraints in a reactive transport model implies that the magnitudes of the oxygen isotope fractionation and sulfur isotope fractionation are correlated under a broad range of sulfate reduction rates in marine and marginal marine environments. This correlation suggests a strong role for the electron donor in controlling the intracellular redox fluxes of sulfur and the fractionation of oxygen isotopes in the natural environment.

Antler, Gilad; Bosak, Tanja; Ono, Shuhei; Sivan, Orit; Turchyn, Alexandra V.

2014-05-01

391

Wnts, Signaling and Sulfates  

NSDL National Science Digital Library

Questions remain about the signaling pathways that control pattern formation during development. Blair describes how sulfated glycosaminoglycans affect several developmentally important signaling pathways, including Wnt-Wingless, Fibroblast growth factor, Hedgehog, and Bone morphogenetic protein-4 signaling. A new secreted sulfatase, Qsulf1, regulates the sensitivity of vertebrate cells to Wnts, possibly by modifying the sulfation of glycosaminoglycans.

Seth S. Blair (University of Wisconsin;Department of Zoology REV)

2001-09-25

392

Usefulness of ytterbium(III) as analytical reagent for total sulfite determination in white wine samples.  

PubMed

Ytterbium(III) is used as reagent for the determination of sulfite by measuring the formation of the Yb(III)-sulfite complex through the variation of the light scattering intensity with time. The low solubility of this complex causes an efficient dispersion of the radiation at 490 nm, which is measured at 980 nm. Each kinetic datum is automatically obtained in only 0.5 s by stopped-flow mixing technique. The application of the initial rate method using a long emission wavelength minimizes the potential interference of fluorescent background signals from the sample matrix. The dynamic range of the calibration graph is 1-250 microg/mL, and the calculated detection limit is 0.35 microg/mL. The precision, expressed as relative standard deviation, is <6%. The method has been applied to the determination of total sulfites in white wine samples, which requires only the sample dilution and the use of two aliquots to improve selectivity. However, the matrix effect found for red wines precludes the application of the method to the direct analysis of these samples. Analytical recoveries ranged from 96.0 to 106.7%. The results obtained with the proposed method agreed with those provided by the p-rosaniline method. Unlike this method, in which toxic reagents are required, the use of ytterbium(III) as analytical reagent shows the advantage of its low acute toxic rating. PMID:15612754

Rodríguez-Díaz, Rafael Carlos; Aguilar-Caballos, Maria Paz; Gómez-Hens, Agustina

2004-12-29

393

Ethanol production from spent sulfite liquor fortified by hydrolysis of pulp mill primary clarifier sludge  

SciTech Connect

Some low-yield sulfite pulping operations ferment spent sulfite liquor (SSL) to remove biochemical oxygen demand associated with dissolved sugars while at the same time generating ethanol as a salable product. Simultaneous saccharification and fermentation (SSF) of primary clarifier sludge in a medium of SSL was proposed as a means of reducing the amount of sludge to be disposed of while at the same time increasing ethanol productivity. In this article, the option of fortifying existing SSL fermenting processes with the sugars produced via in situ enzymatic hydrolysis of sulfite primary clarifier sludge (PCS) has been explored. In 100% SSL PCS hydrolysis rates as high as 3.4 g/(L{center_dot}h) were observed at an initial enzyme loading of 10 filter paper units (FPU)/g PCS. To reduce the deleterious effects of glucose inhibition, single-stage SSF was carried out using cellulose enzymes and Saccharomyces cerevisiae. The production rate of ethanol in SSL was increased by as much as 25% through the SSF process. 12 refs., 4 figs., 2 tabs.

Moritz, J.W.; Duff, S.J.B. [Univ. of British Columbia, Vancouver (Canada)

1996-12-31

394

[Activity and structure of the sulfate-reducing bacterial community in the sediments of the southern part of Lake Baikal].  

PubMed

The rates of sulfate reduction (SR) and the diversity of sulfate-reducing bacteria (SRB) were studied in the sediments of the Posol'skaya banka elevation in the southern part of Lake Baikal. SR rates varied from 1.2 to 1641 nmol/(dm3 day), with high rates (> 600 nmol/(dm3 day)) observed at both deep-water stations and in subsurface silts. Integral SR rates calculated for the uppermost 50 cm of the sediments were higher for gas-saturated and gas hydrate-bearing sediments than in those with low methane content. Enrichment SRB cultures were obtained in Widdel medium for freshwater SRB. Analysis of the 16S rRNA gene fragments from clone libraries obtained from the enrichments revealed the presence of SRB belonged to Desulfosporosinus genus, with D. lacus as the most closely related member (capable of sulfate, sulfite, and thiosulfate reduction), as well as members of the order Clostridiales. PMID:25507445

2014-01-01

395

AnSBBR applied to organic matter and sulfate removal: interaction effect between feed strategy and COD/sulfate ratio.  

PubMed

A mechanically stirred anaerobic sequencing batch reactor containing anaerobic biomass immobilized on polyurethane foam cubes, treating low-strength synthetic wastewater (500 mg COD L(-1)), was operated under different operational conditions to assess the removal of organic matter and sulfate. These conditions were related to fill time, defined by the following feed strategies: batch mode of 10 min, fed-batch mode of 3 h and fed-batch mode of 6 h, and COD/[SO(4)(2-)] ratios of 1.34, 0.67, and 0.34 defined by organic matter concentration of 500 mg COD L(-1) and sulfate concentrations of 373, 746, and 1,493 mg SO(4)(2-) L(-1) in the influent. Thus, nine assays were performed to investigate the influence of each of these parameters, as well as the interaction effect, on the performance of the system. The reactor operated with agitation of 400 rpm, total volume of 4.0 L, and treated 2.0 L synthetic wastewater in 8-h cycles at 30 +/- 1 degrees C. During all assays, the reactor showed operational stability in relation to the monitored variables such as COD, sulfate, sulfide, sulfite, volatile acids, bicarbonate alkalinity, and solids, thus demonstrating the potential to apply this technology to the combined removal of organic matter and sulfate. In general, the results showed that the 3-h fed-batch operation with a COD/[SO(4)(2-)] ratio of 0.34 presented the best conditions for organic matter removal (89%). The best efficiency for sulfate removal (71%) was accomplished during the assay with a COD/[SO(4)(2-)] ratio of 1.34 and a fill time of 6 h. It was also observed that as fill time and sulfate concentration in the influent increased, the ratio between removed sulfate load and removed organic load also increased. However, it should be pointed out that the aim of this study was not to optimize the removal of organic matter and sulfate, but rather to analyze the behavior of the reactor during the different feed strategies and applied COD/[SO(4)(2-)] ratios, and mainly to analyze the interaction effect, an aspect that has not yet been explored in the literature for batch reactors. PMID:19277484

Friedl, Gregor F; Mockaitis, Gustavo; Rodrigues, José A D; Ratusznei, Suzana M; Zaiat, Marcelo; Foresti, Eugênio

2009-10-01

396

75 FR 51055 - Propionic Acid and Salts, and Urea Sulfate; Registration Review Proposed Decisions; Notice of...  

Federal Register 2010, 2011, 2012, 2013

...EPA-HQ-OPP-2010-0650; FRL-8840-5] Propionic Acid and Salts, and Urea Sulfate; Registration Review...decisions for the pesticides propionic acid and salts, and urea sulfate and opens a public comment...pesticide formulations. Propionic acid and its salts, sodium and calcium propionates,...

2010-08-18

397

Dynamic fluorescence quenching of quinine sulfate dication by chloride ion in ionic and neutral micellar environments  

NASA Astrophysics Data System (ADS)

Fluorescence quenching of Quinine sulfate dication (QSD) by chloride-ion (Cl-) in micellar environments of anionic, sodium dodecyl sulfate (SDS), cationic, cetyltrimethylammonium bromide (CTAB) and neutral, triton X-100 (TX-100) in aqueous phase has been investigated by time-resolved and steady- state fluorescence measurements. The quenching follows linear Stern-Volmer relation in micellar solutions and is dynamic in nature.

Joshi, Sunita; Varma Y, Tej Varma; Pant, Debi D.

2014-04-01

398

Identification of key components in the energy metabolism of the hyperthermophilic sulfate-reducing archaeon Archaeoglobus fulgidus by transcriptome analyses  

PubMed Central

Energy conservation via the pathway of dissimilatory sulfate reduction is present in a diverse group of prokaryotes, but is most comprehensively studied in Deltaproteobacteria. In this study, whole-genome microarray analyses were used to provide a model of the energy metabolism of the sulfate-reducing archaeon Archaeoglobus fulgidus, based on comparative analysis of litoautotrophic growth with H2/CO2 and thiosulfate, and heterotrophic growth on lactate with sulfate or thiosulfate. Only 72 genes were expressed differentially between the cultures utilizing sulfate or thiosulfate, whereas 269 genes were affected by a shift in energy source. We identified co-located gene cluster encoding putative lactate dehydrogenases (LDHs; lldD, dld, lldEFG), also present in sulfate-reducing bacteria. These enzymes may take part in energy conservation in A. fulgidus by specifically linking lactate oxidation with APS reduction via the Qmo complex. High transcriptional levels of Fqo confirm an important role of F420H2, as well as a menaquinone-mediated electron transport chain, during heterotrophic growth. A putative periplasmic thiosulfate reductase was identified by specific up-regulation. Also, putative genes for transport of sulfate and sulfite are discussed. We present a model for hydrogen metabolism, based on the probable bifurcation reaction of the Mvh:Hdl hydrogenase, which may inhibit the utilization of Fdred for energy conservation. Energy conservation is probably facilitated via menaquinone to multiple membrane-bound heterodisulfide reductase (Hdr) complexes and the DsrC protein—linking periplasmic hydrogenase (Vht) to the cytoplasmic reduction of sulfite. The ambiguous roles of genes corresponding to fatty acid metabolism induced during growth with H2 are discussed. Putative co-assimilation of organic acids is favored over a homologous secondary carbon fixation pathway, although both mechanisms may contribute to conserve the amount of Fdred needed during autotrophic growth with H2. PMID:24672515

Hocking, William P.; Stokke, Runar; Roalkvam, Irene; Steen, Ida H.

2014-01-01