Precipitation Of Sulfate Salts Research Articles

Urine Immunofixation Electrophoresis for Diagnosis of Monoclonal Gammopathy: Evaluation of Methods for Urine Concentration.

Examination of urine by immunofixation electrophoresis (UIFE) is one of the tests recommended for screening and monitoring of monoclonal gammopathies, especially multiple myeloma. Unlike the serum free light chain measurement, a positive result on urine immunofixation is diagnostic for monoclonal immunoglobulin light chains. Urine is usually concentrated, generally by membrane filtration, prior to electrophoresis. Alternative methods to membrane filtration for urine concentration were examined. Residual urine specimens submitted for urine protein electrophoresis were concentrated by precipitation of the proteins by ammonium sulfate salt precipitation, precipitation with ethanol and acetonitrile, and by desiccation. The concentrated specimens were subjected to immunofixation electrophoresis using antisera to free light chains (FLC). The results were compared with those from conventional immunofixation electrophoresis using specimens concentrated by membrane filtration. Ammonium sulfate, ethanol, and acetonitrile precipitation results were less than satisfactory. Concentration by desiccation provided results comparable, if not better than, those by membrane filtration and conventional UIFE. The cost of desiccation is minimal compared to more than $5.00/specimen cost of concentration by membrane filtration. The differences in the results with conventional UIFE and the method described here are likely due to (a) variability in the reactivity of different antisera to free monoclonal light chains, and (b) obscuration of monoclonal free light chains by co-migration with intact immunoglobulin monoclonal proteins. Concentrating urine by desiccation for immunofixation electrophoresis is technically simple, inexpensive, and provides results comparable to concentrating by membrane filtration. Using FLC provides a more sensitive assay than using conventional antisera.

Cyclotides derived from Viola dalatensis Gagnep: A novel approach for enrichment and evaluation of antimicrobial activity

Cyclotides, plant-derived cysteine-rich peptides, exhibit a wide range of beneficial biological activities and possess exceptional structural stability. Cyclotides are commonly distributed throughout the Violaceae family. Viola dalatensis Gagnep, a Vietnamese species, has not been well studied, especially for cyclotides. This pioneering research explores cyclotides from V. dalatensis as antimicrobials. This study used a novel approach to enhance cyclotides after extraction. The approach combined 30% ammonium sulfate salt precipitation and RP-HPLC. A comprehensive analysis was performed to ascertain the overall protein content, flavonoids content, polyphenol content, and free radical scavenging capacity of compounds derived from V. dalatensis. Six known cyclotides were sequenced utilizing MS tandem. Semi-purified cyclotide mixtures (M1, M2, and M3) exhibited antibacterial efficacy against Bacillus subtilis (inhibitory diameters: 19.67–23.50 mm), Pseudomonas aeruginosa (22.17–23.50 mm), and Aspergillus flavus (14.67–21.33 mm). The enriched cyclotide precipitate from the stem extract demonstrated a minimum inhibitory concentration (MIC) of 0.08 mg/mL against P. aeruginosa, showcasing significant antibacterial effectiveness compared to the stem extract (MIC: 12.50 mg/mL). Considerable advancements have been achieved in the realm of cyclotides, specifically in their application as antimicrobial agents.

Increasing inhibition performance of simultaneous precipitation of calcium and strontium sulfate scales using a new inhibitor — Laboratory and field application

In this work, the calcium sulfate (anhydrite) and strontium sulfate precipitation simultaneous prediction was performed at various reservoir pressures, temperatures, and mixing ratios of injection and formation water. In addition, in order to prevent the precipitation of calcium and strontium sulfate scale, the inhibition performance of five various well-known scale inhibitors was evaluated by conducting different experiments. The results showed that the possibility of calcium and strontium sulfate precipitation was directly proportional to the temperature and inversely proportional to pressure. The worst scenario for the simultaneous calcium and strontium sulfate scale formation was observed in a mixing ratio of 1:1 injection and formation water. A mixture of reagents (new inhibitors) — DPAAI (three phosphonate scale inhibitors, ammonium bifluoride, isopropyl alcohol, and water) was developed in order to enhance the prevention performance of calcium and strontium sulfate salt precipitation. DPAAI had an efficiency of 94% under static conditions, and its effectiveness was not changed by increasing the temperature up to 150 °C. The induction period of strontium sulfate crystallization in the presence of DPAAI was 70 min, which was 2.89 times longer than in a blank case. The interfacial tension of DPAAI and oil was reduced more than 10 times in the presence of an alcohol propoxy sulfate at a mass concentration of 1.5%. Furthermore, the rock permeability with the use of DPAAI was improved from 33% to 95% of the initial permeability. The squeeze lifetime of DPAAI for preventing the simultaneous calcium and strontium sulfate scale precipitation was about 85% longer than the squeeze lifetime of the investigated common phosphonate scale inhibitors.

The role of hydrothermal sulfate reduction in the sulfur cycles within Europa: Laboratory experiments on sulfate reduction at 100 MPa

There are several lines of evidence for the subsurface ocean within Europa; however, its oceanic chemistry and geochemical cycles are largely unknown. The recent observations by large telescopes show that exogenic sulfur ions and SO2 are implanted from Io and accumulate as sulfuric acids in Europa's trailing hemisphere. This suggests that a large amount of sulfate could have been supplied into the ocean over geological timescales. The telescope observations also suggest that chloride salts appear on chaotic terrains of Europa, suggesting that the primary oceanic anion may be chloride despite a supply of sulfate into the ocean. These observations imply the presence of possible sinks of exogenic sulfate within the ocean. Here, we report the results of laboratory experiments on hydrothermal sulfate reduction under the pressure conditions that correspond to Europa's seafloor. Using a Dickson-type experimental system, we obtain the reaction rate of sulfate reduction at a pressure of 100 MPa and temperature of 280 °C for various pH levels (pH 2–7). We find strong pH dependence and little pressure dependence of the reaction rate. Sulfate reduction proceeds effectively at fluid pH < 6, whereas it is kinetically inhibited at fluid pH ~7. These results suggest that, if hydrothermal fluid pH is <6, hydrothermal sulfate reduction within Europa can be a sink of exogenic sulfate within the ocean in addition to precipitation of sulfate salts. Such acidic fluid pH may be achieved if hydrothermal activity is hosted by basaltic rocks. We suggest the importance of the thermal evolution of the rocky interior for both the ocean chemistry and sulfur cycles of Europa.

Contaminant generation and transport from mine pit lake to perennial stream system: Multidisciplinary investigations at the Big Ledge Mine, Nevada, USA

The Big Ledge mine located in northeastern Nevada, USA is a former barite mine site that now hosts an acidic pit lake and highly concentrated waste rock seepage, which flows into an intermittent stream. In an effort to identify the source(s) of the seepage, stable isotopic analyses were conducted (δ2H, δ18OH2O, δ18OSO4, and δ34S) in the pit lake, seepage, and groundwater. Additionally, inverse geochemical modeling was utilized to evaluate mixing relationships and mineral equilibria. Mass-balance calculations were also performed on the seepage/stream system to quantify discrete and diffuse solute inputs to surface waters. The stable isotopic composition of the pit lake and seepage display evaporative enrichment with the seeps being intermediate between the pit lake and groundwater, indicating that water in the seeps is partially sourced in the upgradient pit lake. Inverse modeling corroborates the isotopic mixing relationships, suggests that sulfide minerals could be dissolving along the flow path in the waste rock, and predicts the precipitation of sulfate salts from the concentrated seepage waters. Mineralogical analysis of efflorescent salts at the site, including epsomite (MgSO4·7H2O), pickeringite (MgAl2[SO4]4·22H2O), and melanterite (FeSO4·7H2O), corroborates the inverse modeling. Mass-balance calculations indicate the presence of diffuse acid mine drainage inflows along the creek, which, along with discrete inflows from waste rock seepage, contribute to sustained dissolved-metal transport in the perennial Tabor Creek downgradient from the mine.

Solid state fermentation of Bacillus gottheilii M2S2 in laboratory-scale packed bed reactor for tannase production

Production of tannase was performed in packed bed reactor filled with an inert support polyurethane foam (PUF) using Bacillus gottheilii M2S2. The influence of process parameters such as fermentation time (24–72 h), tannic acid concentration (0.5–2.5% w/v), inoculum size (7–12% v/v), and aeration rate (0–0.2 L/min) on tannase production with PUF were analyzed using one variable at a time (OVAT) approach. The outcome of OVAT was optimized by central composite design. Based on the statistical investigation, the proposed mathematical model recommends 1% (w/v) of tannic acid, 10% (v/v) of inoculum size and 0.13 L/min of aeration rate for maximum production (76.57 ± 1.25 U/L). The crude enzyme was purified using ammonium sulfate salt precipitation method followed by dialysis. The biochemical properties of partially purified tannase were analyzed and found the optimum pH (4.0), temperature (40 °C) for activity, and Km (1.077 mM) and Vmax (1.11 µM/min) with methyl gallate as a substrate. Based on the SDS-PAGE analysis, tannase exhibited two bands with molecular weights of 57.5 and 42.3 kDa. Briefly, the partially purified tannase showed 4.2 fold increase (63 ± 1.60 U/L) in comparison to the submerged fermentation and the production of tannase was validated by using NMR spectrometer.

Current knowledge of external sulfate attack

This paper offers an update of the current understanding of sulfate attack, with emphasis on the sulfates present in an external water source percolating through, and potentially reacting with, the cement matrix. The paper considers the explanations put forward to explain sulfate attack, both from a chemical and microstructural perspective. Similarly, this paper reviews work on the physical damage caused by the precipitation of sulfate salts in porous materials. With the increased use of binary and ternary blends, this paper also considers the impact of binder composition on sulfate resistance, and similarly reviews how the nature of the sulfate species can affect the nature and extent of any deterioration. This then leads on to the important consideration of differences between field- and lab-based studies, reviewing the effect of various experimental parameters on sulfate resistance. This latter topic is of great importance to anyone who wishes to carry out such experiments.

Purification of Peroxidase from Horseradish (Armoracia rusticana) Roots

Peroxidase (EC 1.11.1.7) from horseradish ( Armoracia rusticana ) roots was purified using a simple, rapid, three-step procedure: ultrasonication, ammonium sulfate salt precipitation, and hydrophobic interaction chromatography on phenyl Sepharose CL-4B. The preparation gave an overall yield of 71%, 291-fold purification, and a high specific activity of 772 U mg(-1) protein. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that the purified enzyme was homogeneous and had a molecular weight of approximately 40 kDa. The isolated enzyme had an isoelectric point of 8.8 and a Reinheitszahl value of 3.39 and was stable when stored in the presence of glycerol at -20 degrees C, with >95% retention of original enzyme activity for at least 6 months. Maximal activity of purified horseradish peroxidase (HRP) was obtained under different optimized conditions: substrate (guaiacol and H(2)O(2)) concentrations (0.5 and 0.3 mM, respectively), type of buffer (50 mM phosphate buffer), pH (7.0), time (1.0 min), and temperature of incubation (30 degrees C). In addition, the effect of HRP and H(2)O(2) in a neutral-buffered aqueous solution for the oxidation of phenol and 2-chlorophenol substrates was also studied. Different conditions including concentrations of phenol/2-chlorophenol, H(2)O(2), and enzyme, time, pH, and temperature were standardized for the maximal activity of HRP with these substrates; under these optimal conditions 89.6 and 91.4% oxidations of phenol and 2-chlorophenol were obtained, respectively. The data generated from this work could have direct implications in studies on the commercial production of this biotechnologically important enzyme and its stability in different media.

Mixing relationships and the effects of secondary alteration in the Wishstone and Watchtower Classes of Husband Hill, Gusev Crater, Mars

The Wishstone and Watchtower Class rocks on Husband Hill preserve evidence for a geochemical relationship consistent with two‐component mixing between a high Al2O3, TiO2, CaO, Na2O, P2O5 end‐member and a second end‐member enriched in the elements MgO, Zn, S, Br, and Cl. The first end‐member appears to be reasonably well represented by rocks of the Wishstone Class, while the second end‐member is consistent with a chemical component, not represented by any lithology encountered by Spirit. The Watchtower Class appears to be an intermediate in the mixture. The concentration of the redox sensitive elements Fe and Mn display no systematic variation between rock classes, and the Fe‐redox state of the Watchtower Class is elevated relative to the Wishstone Class. Combined with evidence for two‐component mixing, these observations suggest that the mixture was generated by interaction between an initially Wishstone‐like deposit and a fluid phase enriched in the elements MgO, Zn, S, Br, and Cl. The fluid phase may have been weakly acidic (pH &gt; 4) to basic (pH ≥ 9), resulting in oxidation and immobilization of Fe and Mn. A number of secondary rock surface alteration processes which obscure the mixing relationship are also identified. These include (1) removal of CaO and P2O5 from rock surfaces by dissolution of Ca‐phosphate minerals under acidic, low water‐to‐rock ratio conditions, (2) addition of SO3 to rock surfaces via aeolian deposition of high SO3 soil and/or precipitation of sulfate salts from solution, and (3) homogenization of rock surface chemistry by soil contamination.

Identification of IgE-binding proteins from Lepidoglyphus destructor and production of monoclonal antibodies to a major allergen

The allergen composition of one of the most important storage mites, Lepidoglyphus destructor, has been studied by immunodetection after SDS-PAGE with individual patient sera. An allergenic polypeptide of 14 kDa was identified with 95% of the sera. This major allergen was isolated in the supernatant of 60% ammonium sulfate salt precipitation of the whole extract, which was subsequently used to immunize BALB/c mice so as to produce monoclonal antibodies. Four mAbs recognizing molecules with IgE-binding ability were obtained. The specificity of the mAbs was assayed against different allergenic extracts, and the molecules recognized by them were characterized by immunoblotting. Two mAbs (Le5B5 and Le9E4) were directed to the 14-kDa allergen; the other two to several proteins of lesser allergenic significance.

Migration and Leaching of Metals from Old Mine Tailings Deposits

ABSTRACTLeaching of heavy metals by ground water passing through mine tailings is caused by the oxidation of sulfides through the action of microorganisms. The pH of the ground water entering the tailings system is reduced by mechanisms within the tailings system itself. Action of sulfide‐oxidizing and sulfur‐oxidizing bacteria causes the formation of sulfuric acid, thereby increasing the H+ and SO42− concentration within the system. Metal ions go into solution as metal sulfates, and the concentration of H2S increases by the interaction of H+ and S2− Increase in H2S creates an environment suitable for the growth of sulfate‐reducing bacteria which converts SO42− to S2− and simultaneously precipitates metal sulfides at a pH near 6.6. Decrease in pH with depth destroys sulfate‐reducing bacteria, and dissolution and leaching of the tailings increase.Four lines of evidence demonstrate the presence of microorganisms in the tailings system: (1) Fe‐Mn concretions below the water table at Cataldo Mission Flats, (2) fixation of Na and K below the water table, (3) precipitation of sulfate salts on the surface of Cataldo Mission Flats, and (4) experiments on two sets of tailings samples, one from the surface which showed predominant aerobic activity and one from below the water table which showed predominant anaerobic activity. Where oxygen is sufficient, iron oxidizing bacteria oxidize Fe2+ to Fe3+ which forms an insoluble hydroxide. Consequently, very little iron is found in the ground water coming from the system. The combination of these mechanisms produces poor‐quality ground water with respect to metals.