Addition Of Hexametaphosphate Research Articles

Enhanced ATP and antioxidant levels for cAMP biosynthesis by Arthrobacter sp. CCTCC 2013431 with polyphosphate addition.

When citrate and pyruvate were utilized to strengthen ATP generation for high cAMP production, oxidative stress became more severe in cells resulting in lower cell viability and cAMP formation at the late fermentation phase. To further improve cAMP biosynthesis, the effects of polyphosphate on cAMP fermentation performance together with intracellular ATP and oxidation levels were investigated under high oxidative stress condition and then high efficient cAMP fermentation process based on polyphosphate and salvage synthesis was developed and studied. With 2g/L-broth sodium hexametaphosphate added at 24h was determined as the optimal condition for cAMP production by Arthrobacter sp. CCTCC 2013431 in shake flasks. Under high oxidative stress condition caused by adding 15mg/L-broth menadione, cAMP contents and cell viability were improved greatly due to hexametaphosphate addition and also exceeded those of control (without hexametaphosphate and menadione added) when fermentations were conducted in a 7 L bioreactor. Meanwhile, ATP levels and antioxidant capacity were improved obviously by hexametaphosphate as well. Moreover, a fermentation process with hexametaphosphate and hypoxanthine coupling added was developed by which cAMP concentration reached 7.25g/L with an increment of 87.1% when compared with only hypoxanthine added batch and the high ROS contents generated from salvage synthesis were reduced significantly. Polyphosphate could improve intracellular ATP levels and antioxidant capacity significantly under high oxidative stress condition resulting in enhanced cell viability and cAMP fermentation production no matter by de novo synthesis or salvage synthesis.

Effects of Sodium Hexametaphosphate Addition on the Dispersion and Hydration of Pure Calcium Aluminate Cement.

The effects of sodium hexametaphosphate (SHMP) addition on the dispersion and hydration of calcium aluminate cement were investigated, and the relevant mechanisms discussed. The content of SHMP and the adsorption capacity of SHMP on the surface of cement particles were estimated using plasma adsorption spectroscopy and the residual concentration method. The rheological behavior of hydrate, ζ-potential value of cement particles, phase transformation and the microstructure of the samples were determined by coaxial cylinder rheometer, zeta probe, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results indicate that SHMP readily reacted with Ca2+, forming complexes [Ca2(PO3)6]2− ions which were subsequently adsorbed onto the surfaces of cement particles. When the content of SHMP was 0.05%, the adsorption ratio reached 99%. However, it decreased to 89% upon further increasing the addition of SHMP to 0.4%. The complexes [Ca2(PO3)6]2− adsorbed onto the surfaces of cement particles inhibited the concentration of Ca2+ and changed ζ-potential, resulting in enhanced electrostatic repulsive force between the cement particles and reduced viscosity of cement-water slurry. The experimental results indicate that the complexes [Ca2(PO3)6]2− covering the surfaces of cement particles led to a delayed hydration reaction, i.e., they extended the hydration time of the cement particles, and that the optimal addition of SHMP was found to be about 0.2%.

Influence of sodium hexametaphosphate addition on the functional properties of milk protein concentrate solutions containing transglutaminase cross-linked proteins

The functional properties of milk protein concentrate (MPC) powders are often hindered by their poor solubility. Calcium chelating salts have been shown to improve powder solubility, but generally their action contributes to higher viscosity due to disintegration of casein micelles and higher levels of serum-phase calcium. To help mitigate increases in viscosity associated with calcium chelation, transglutaminase (TGase), an enzyme that covalently crosslinks protein, was employed in an effort to stabilise the casein micelle structure. Sodium hexametaphosphate (SHMP) was added to control (C-MPC) and TGase crosslinked MPC (TG-MPC) dispersions at concentrations of 5, 12.5 and 25 mm prior to analysis. TG-MPC dispersions had lower viscosity than C-MPC dispersions across all SHMP concentrations studied. Crosslinking limited micelle dissociation on SHMP addition and led to greater retention of the white colour of the protein dispersions, while the turbidity of C-MPC dispersions decreased with increasing SHMP addition.

The effects of sodium hexametaphosphate addition on the physicochemical properties and microstructure of the milk fat globule membrane (MFGM) in liquid milk after freezing

This research examined the effects of sodium hexametaphosphate on the physicochemical properties and the microstructure of the milk fat globule membrane (MFGM) after freezing. The particle size distribution showed that the peak of the MFGM in the controlled sample was higher than the peak in the frozen sample. The MFGM sample that contained the highest concentration of sodium hexametaphosphate displayed the highest peak. The MFGM samples with the highest concentrations of sodium hexametaphosphate were more stable than the samples with the lowest concentrations. Sodium dodecyl sulfate Polyacrylamide gel electrophoresis and scanning electron microscopy showed sizeable destruction of the MFGM after freezing.

Inhibitory effect of phosphates on magnesium lactate efflorescence formation in dry-fermented sausages

This study aimed to prevent the phenomena of efflorescence formation on the surface of dry fermented sausages due to the complexation of efflorescence forming cations with phosphates. Efflorescence formation is a critical issue constituting a major quality defect, especially of dry fermented sausages. Different phosphates (di- and hexametaphosphate) were added (3.0g/kg) to the sausage batter. As a hypothesis, these additives should complex with one of the main efflorescence-causing substances such as magnesium. The formation of efflorescences was determined for dry fermented sausages without phosphate addition, with diphosphate, or hexametaphosphate addition during 8weeks of storage under modified atmosphere. The visual analyses of the sausage surface revealed high amounts of efflorescences for the control (42.2%) and for the sausages with added diphosphate (40.9%), whereas the sausages containing hexametaphosphate had significantly reduced amounts of efflorescence formation, showing only 11.9% efflorescences after 8weeks of storage. This inhibition was a result of strong complexation of hexametaphosphate with magnesium ions, thus preventing the diffusion of magnesium towards the sausage surface. This can be explained by the magnesium content on the sausage surface that increased by 163.9, 127.8, and 52.8% for the sausages without phosphate, diphosphate, and hexametaphosphate addition, respectively. The mass transport of lactate and creatine was not affected by phosphate addition. Isothermal titration calorimetry confirmed that, theoretically, 4.5g/kg of diphosphate or 2.8g/kg hexametaphosphate are required to complex 0.2g/kg magnesium ions naturally occurring in dry fermented sausages and, thus, the chosen overall phosphate concentration of 3.0g/kg was enough when adding hexametaphosphate, but not for diphosphate, to inhibit the efflorescence formation.

Use of dispersants in flotation of molybdenite in seawater

Coating of valuable mineral particles by hydrophilic slimes is known to depress flotation of such particles. This is referred to as a slime-coating. Such a slime coating takes place in the flotation of molybdenite in seawater when pH of the pulp is raised to depress pyrite and Mg(OH)+ hydroxy-complexes and precipitating magnesium hydroxide accumulate on the molybdenite surface. The dispersant tested in this paper, sodium hexametaphosphate, is shown to be able to restore molybdenite flotation in the pH range in which it is depressed by magnesium species. Addition of hexametaphosphate was found not to affect floatability of pyrite.

Fluoride gel supplemented with sodium hexametaphosphate reduces enamel erosive wear in situ

ObjectiveThis study evaluated the effect of fluoride gels, supplemented or not with sodium hexametaphosphate (HMP), on enamel erosive wear in situ. MethodsTwelve healthy volunteers wore palatal appliances containing four bovine enamel discs. Subjects were randomly allocated into four experimental phases (double-blind, crossover protocol) according to the gels: Placebo (no fluoride or HMP), 1% NaF, 2% NaF, and 1% NaF+9% HMP. Enamel discs were selected after polishing and surface hardness analysis, and treated only once with the respective gels prior to each experimental phase. Erosion (ERO) was performed by extra-oral immersion of the appliance in 0.05M citric acid, pH 3.2 (four times/day, five minutes each, 5 days). Additional abrasion (ERO+ABR) was produced on only two discs by toothbrushing with fluoridated dentifrice after ERO (four times/day, 30s, 5 days). The specimens were submitted to profilometry and hardness analysis. The results were analyzed by two-way ANOVA and the Student–Newman–Keuls test (p<0.05). ResultsThe 1% NaF+9% HMP gel promoted significantly lower enamel wear for ERO compared to the other groups, being statistically lower than 1% NaF and Placebo for ERO+ABR. Similarly, the lowest values of integrated lesion area were found for 1% NaF+9% HMP and 2% NaF, respectively, for ERO and ERO+ABR. ConclusionThe addition of HMP to the 1% NaF gel promoted greater protective effect against ERO and ERO+ABR compared to the 1% NaF gel, achieving similar protective levels to those seen for the 2% NaF gel. Clinical significanceGel containing 1% NaF+9% HMP showed a high anti-erosive potential, being a safer alternative when compared to a conventional 2% NaF gel.

The effect of hexametaphosphate addition during milk powder manufacture on the properties of reconstituted skim milk

Skim milk powders with various levels of sodium hexametaphosphate (NaHMP) were prepared. Reconstituted skim milk samples were prepared from these powders. NaHMP slightly reduced the pH, markedly reduced the serum and ionic calcium and markedly increased the serum phase orthophosphate levels of the milks. This shift in the mineral equilibrium resulted in a drastic reduction in casein micelle integrity, with a marked dissociation of casein from the micelles. κ-Casein was the predominant casein dissociated, although significant levels of αS-casein and β-casein were also transferred to the serum phase. This dissociation of the casein micelles caused a marked decrease in size and scattering properties of the casein micelles. In addition, a small decrease in the zeta potential of the casein micelles in the milk was observed. Heat treatment of the milks with added NaHMP induced further dissociation of κ-casein, although much of the αS-casein and β-casein re-associated with the micelles.

Effect of probe sonication and sodium hexametaphosphate on the microhardness and wear behavior of electrodeposited Ni–SiC composite coating

Electrodeposited Ni–SiC composite coating is the most widely used engineering coating. Ni–SiC coating is bestowed with higher wear resistance and microhardness compared to plain nickel. In this study, the feasibility of using sodium hexametaphosphate as a dispersant in the electrodeposition of Ni–SiC composite coating has been investigated. The effect of sodium hexametaphosphate and probe sonication on the microhardness, microstructure and wear resistance of the electrodeposited Ni–SiC composite coating has been studied. X-ray photoelectron spectroscopy analysis of the coatings showed the absence of Na and P elements from sodium hexametaphosphate in the bath. Ni–SiC coating deposited using probe sonication followed by the addition of sodium hexametaphosphate exhibited microhardness as high as 680HK. The microstructure of the coatings varied with probe sonication and SHMP addition and Ni–SiC–PS–SHMP coating possessed lowest roughness. This study has revealed that a synergistic combination of probe sonication of the electrolyte bath containing particles followed by sodium hexametaphosphate addition enhances the co-deposition of finer SiC particles and thereby enhances the coating properties like microhardness and wear resistance.

Enhanced permanganate in situ chemical oxidation through MnO 2 particle stabilization: Evaluation in 1-D transport systems

In situ chemical oxidation using permanganate is an increasingly employed approach to organic contaminant remediation at hazardous waste sites. Manganese dioxide (MnO 2) particles form as a by-product of the reaction of permanganate with contaminants and naturally-reduced subsurface materials. These particles are of interest because they have the potential to deposit in the subsurface and impact the flow regime in/around permanganate injection, including the well screen, filter pack, and the surrounding subsurface formation. Control of these particles can allow for improved oxidant injection and transport, and contact between the oxidant and contaminants of concern. Sodium hexametaphosphate (HMP) has previously been identified as a promising aid to stabilize MnO 2 in solution when included in the oxidizing solution, increasing the potential to inhibit particle deposition and impact subsurface flow. The goal of the experimental studies described herein was to investigate the ability of HMP to prevent particle deposition in transport studies using four different types of porous media. Permanganate was delivered to a contaminant source zone (trichloroethylene) located within four different media types with variations in sand, clay, organic carbon, and iron oxides (as goethite) content. Deposition of MnO 2 within the columns was quantified with distance from the source zone. Experiments were repeated in replicate columns with the inclusion of HMP directly with the oxidant delivery solution, and MnO 2 deposition was again quantified. While total MnO 2 deposition within the 60 cm columns did not change significantly with the addition of HMP, deposition within the contaminant source zone decreased by 25–85%, depending on the specific media type. The greatest differences in deposition were observed in the goethite-containing and clay-containing columns. Columns containing these two media types experienced completely plugged flow in the oxidant-only delivery systems; however, the addition of HMP prevented this plugging within the columns, increasing the oxidant throughput.

Age gelation in UHT-processed reconstituted concentrated skim milk

Summary UHT reconstituted concentrated skim milks made from high-heat powder had considerably longer gelation times than those made from medium- or low-heat powders. Addition of hexametaphosphate to the concentrated milk before UHT processing markedly delayed the onset of gelation during storage. Sediment formation was greatest in the UHT concentrated skim milk made using high-heat powder followed by samples made using medium- and low-heat powders, respectively. The extent of proteolysis, as measured by 12% TCA-soluble amino groups, increased at a faster rate in the UHT milks stored at 40°C than in those stored at 22°C but decreased with increasing heat treatment of the milk prior to powder manufacture. The electrophoretic patterns of samples stored at 22°C clearly showed the breakdown of β-casein with a corresponding increase in slower moving bands, presumably γ-casein and proteose-peptone components. However, storage of samples at 40°C resulted in diffused ‘blurred’ protein patterns with some protein material not entering the resolving gel. At 22°C there was some evidence of proteolysis but no evidence of high molecular weight polymer formation, while at 40°C both proteolysis and high molecular weight polymer formation increased with storage time. It appeared that both physico-chemical and proteolytic processes play some part in the mechanism of gelation in UHT reconstituted concentrated skim milk.

EFFECTS OF SALT REDUCTION ON THE RHEOLOGICAL AND GELATION PROPERTIES OF WHITE AND DARK POULTRY MEAT BATTERS

The rheological and gelation properties of poultry dark and white meat batters prepared with average and reduced NaCl levels (2%, 1% and 0%) and with 0.5% hexametaphosphate (HMP) added to the 1% salt batters were studied. Lowering the salt content decreased the shear stress in both the white and dark meat at the same shear rates. HMP addition to the 1% NaCl treatments increased the shear stress in the dark meat but not in the white meat at the same shear rates using a concentric cylinder viscometer. The relationship between the rotor angular velocity and shear stress of the raw batters was nonlinear and resembled a pseudoplastic behaviour with yield stress in all cases. Plots of the modulus of rigidity (G) versus cooking temperature indicated that white meat always exhibited higher G than that of dark meat. The highest G was observed in the white meat with 2.0% NaCl and the lowest in the dark meat with no salt. The batters with no salt also exhibited gel formation, however with lower G values.

Scale Prevention in Brine Preheater by the Addition of Hexametaphosphate

Scale Prevention in Brine Preheater by the Addition of Hexametaphosphate