• Microbiology and Biotechnology Letters
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• v.28 no.1
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• pp.33-38
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• 2000

In order to produce ascorbic acid-2-phosphate from ascorbic acid, bacteria capable of transforming ascorbic acid to ascorbic acid-2-phosphate were isolated from soils and the stock cultures in our laboratory. Among them, a newly isolated bacterium LSH-3 having the best ability of producing ascorbic acid-2-phosphate was selected and partially identified as Pseudomonas sp. The optimum conditions for the production of ascorbic acid-2-phosphate from ascorbic acid and using its resting cells as the source os enzyme were investigated. The results were summarized as follows: The optimum cultivation time and the cell weight for the production of ascorbic acid-2-phosphate was 14 hours and 100g/I(wet weight), respectively. And 0.1%(v/v) Trition X-100 was the most effective surfactant. The optimum concentrations of ascorbic acid and pyrophosphate were 400mM and 500mM, respectively, which led to produce 14.54g/I of ascorbic acid-2-phosphate. The most effective buffer was 50mM sodium acetate. The optimum pH and temperature were 4.5 and $40^{\circ}C$, respectively. Under the above conditions, 17.71 g/I of ascorbic acid-2-phosphate was produced from ascorbic acid after 32 hour-incubation, which corresponded to 17.5% of conversion rate based on ascorbic acid.

• Food Science of Animal Resources
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• v.35 no.4
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• pp.515-523
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• 2015

The effects of reducing fat levels from 30% to 20% and salt concentrations from 1.5% to 1.0% by partially substituting incorporated phosphate and sea mustard were investigated based on physicochemical properties of reduced-fat / low-NaCl meat emulsion systems. Cooking loss and emulsion stability, hardness, springiness, and cohesiveness for reduced-fat / low-NaCl meat emulsion systems with 20% pork back fat and 1.2% sodium chloride samples with incorporation of phosphate and sea mustard were similar to the control with 30% pork back fat and 1.5% sodium chloride. Results showed that reduced-fat / low-NaCl meat emulsion system samples containing phosphate and sea mustard had higher apparent viscosity. The results of this study show that the incorporation of phosphate and sea mustard in the formulation will successfully reduce fat and salt in the final meat products.

• Applied Chemistry for Engineering
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• v.30 no.5
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• pp.562-568
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• 2019

Cylindrical shape extrudates of calcium silicate hydrate (CSH) were prepared using different percentages of polyvinyl alcohol (PVA) / sodium alginate (SA) mixtures as binders and an aqueous solution containing 6% $H_3BO_3$ and 3% $CaCl_2$ was used as a cross linking agent. As the quantity of alginate increases, the phosphate removal efficiency and capacity were decreased. Among four different extrudate samples, the sample prepared by 8% PVA + 2% SA showed the highest phosphate removal efficiency (59.59%) and capacity (29.97 mg/g) at an initial phosphate concentration of 100 ppm and 2.0 g/L adsorbent dosage. Effects of the adsorbent dosage, contact time and initial phosphate concentration on the sample were further studied. The removal efficiency and capacity obtained by a 4.0 g/L adsorbent dose at an initial phosphate concentration of 100 ppm in 3 h were 79.38% and 19.96 mg/g, respectively. The experimental data of kinetic and isotherm measurements followed the pseudo-second-order kinetic equation and Langmuir isotherm model, respectively. These results suggested that the phosphate removal was processed via a chemisorption and a monolayer coverage of phosphate anions was on the CSH surface. The maximum adsorption capacity ($q_{max}$) was calculated as 23.87 mg/g from Langmuir isotherm model.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.2
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• pp.314-322
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• 2004

The production of a glucan was affected by the concentration of ions and buffer solutions, and nutrients in an oral cavity. In this study, the effects of ions and buffer solutions on the mRNA expression of gtfD gene in Streptococcus mutans, an important causative agent of dental caries, were investigated by Fluorescent in situ hybridization(FISH). At first, ions and buffer solutions had little effect on the multiplication of Streptococcus mutans. The green fluorescence according to the mRNA expression of gtfD gene was detected in the BHI broth containing 1% sucrose. The intensities of the green fluorescence were strong at 0.25mM of $CaCl_2$. Little fluorescence was detected by the addition of KCl, except far 10mM KCl at which fluorescence intensities were similar to those of the control. Fluorescence intensities were weak at each concentration of $MgCl_2$ when compared to the control. As for buffer solutions, fluorescence intensities were similar to those of the control at each concentration of buffer solutions, except that they were little detected at 100mM of potassium phosphate.

• Corrosion Science and Technology
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• v.9 no.3
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• pp.137-141
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• 2010

Sodium nitrite is widely used as one of the popular corrosion inhibitors for the protection of ferrous metal in closed cooling water system, such as a diesel engine and a chiller. The optimum treatment conditions are studied through laboratory tests using linear polarization resistance (LPR) technique. Corrosion rate of the carbon steel electrode could be maintained less than $2.5{\times}10^{-3}$ mmpy in the test condition of 500 ppm as ${NO_2}^-$, 200 ppm as $Cl^-$, $70^{\circ}C$ and pH 6.8. The pH control is confirmed not to be an important factor in the protection of carbon steel by sodium nitrite inhibitor. The addition of tolyltriazole was needed for the protection of the copper alloy in the sodium nitrite treatment system.

• Analytical Science and Technology
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• v.12 no.2
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• pp.99-104
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• 1999

A stepwise gradient elution with two wavelengths detection was performed for the separation and determination of some anions in saline water. The eight anions such as iodate, bromate, nitrite, bromide, nitrate, chromate, iodide and thiocyanate were successfully separated using AS-7 column and sodium chloride/sodium phosphate buffer solution as an eluant within 40 min. The separation behaviors of anions were studied at various sodium chloride concentrations. The peak shapes of anions of bromate, nitrite, bromide and nitrate gradually broadened as the concentration of sodium chloride increased until 1.0 M in the sample solutions. However, no effect was observed in the peak shapes of chromate, iodide and thiocynate. A good linearity was obtained at the range of ppm(mg/L). The detection limit was proved to be $10-720{\mu}g/L$ for the eight anions with $50{\mu}L$ injection volume. This method was applied to the determination of $Br^-$, ${NO_3}^-$ and $I^-$ in sea water.

• Applied Biological Chemistry
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• v.38 no.5
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• pp.376-381
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• 1995

Thermus caldophilus GK24 was selected as sources of thermostable alkaline phosphatase from a survey of extreme thermophile. T. caldophilus GK24 was tested for production of alkaline phosphatase by addition of various concentration of sodium glutamate, bactotryptone, glucose and yeast extract to basal salts. Sodium glutamate was found to be effective for the alkaline phosphatase induction. The optimal induction medium for production of alkaline phosphatase involves the addition of 0.3% sodium glutamate, 0.2% bactotryptone and 0.5% glucose to basal salts. The activity of the enzyme in optimal induction medium increased nearly 6-fold/ml than basal medium and 27.5-fold/ml than standard medium. T. caldophilus GK24 alkaline phosphatase was found to be inducible. When starved of inorganic phosphate, T. caldophilus GK24 produces the enzyme alkaline phosphatase. The addition of inorganic phosphate to growth medium had a repressive effect on enzyme synthesis.

• Journal of Food Hygiene and Safety
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• v.33 no.6
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• pp.466-473
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• 2018

An analytical method of sodium polyacrylate in processed food products was developed and monitored by using size-exclusion chromatography. GF-7M HQ column and UV/VIS detector were selected based on peak shape and linearity. Flow rate, column oven temperature, and mobile phase were selected as 0.6 mL/min, $45^{\circ}C$, and 50 mM sodium phosphate buffer of pH 9.0, respectively. Samples for analysis of sodium polyacrylate were extracted with 50 mM sodium phosphate buffer of pH 7.0 for 3 hr at $20^{\circ}C$ and 150 rpm. Analytical method validation revealed proper selectivity and calibration curve was selected in the range of 50-500 mg/L, and correlation coefficient of calibration curve was more than 0.9985. Limit of detection of sodium polyacrylate was 10.95 mg/kg and limit of quantification was 33.19 mg/kg. Accuracy and coefficient of variation for sodium polyacrylate analysis was 99.6-127.6%, 3.0-8.3% for intra-day and 94.3-121.9%, 1.3-2.6% for inter-day, respectively. Sodium polyacrylate was detected in 40 samples among monitored 125 processed food products. Detected contents were less than 0.2%, limited by the Food Additives Code. Results suggest the established size-exclusion chromatography method could be used to analyze sodium polyacrylate in processed food products.

• Journal of Pharmaceutical Investigation
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• v.36 no.3
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• pp.161-167
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• 2006

The objective of this study was to investigate the dissolution patterns of variety of orally administered drug products available on the market. It aimed to understand their dissolution behaviors on the basis of the biopharmaceutics classification system (BCS) concept. On the tenets of BCS, several active pharmaceutical ingredients were selected: fluoxetine hydrochloride (class I), naproxen sodium (class ll), pyridostigmine bromide (class III), furosemide (class IV) and simvastatin (class IV). Typical dissolution media used in this study were pH 1.2, pH 4 & 6.8 phosphate buffers, and water. In cases, particular dissolution media specified in the KP and/or USP were used. Dissolution patterns of fluoxetine hydrochloride and pyridostigmine bromide products were characterized by their rapid release In addition, their dissolution characteristics were relatively unaffected by the type of a dissolution medium. Similar dissolution patterns were observed with pH 1.2, pH 4 & 6.8 phosphate buffers and water. By sharp contrast, poor dissolution patterns were noticed with naproxen sodium products, when pH 1.2 and pH 4 phosphate buffer were used. Improvements in its dissolution were achieved by switching the dissolution media to pH 6.8 phosphate buffer or water. Unsatisfactory dissolution data also were observed with a simvastatin product, when it was subject to dissolution tests by use of a surfactant-free pH 1.2, pH 4 & 6.8 phosphate buffers and water. All the release patterns reported in this study were best understood when BCS concepts were implemented. Our results demonstrated that a BCS-based drug classification should be considered first to choose a dissolution test/method and set up dissolution specification.

• Journal of the Korean Graphic Arts Communication Society
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• v.15 no.2
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• pp.77-90
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• 1997

Positive type presensitized offset plate developer were blended by quantitative analysis method. The test had been proceeeded to check variation of developability, shelf life and tone reproduction by SiO2/Na2O ratio to PS plate developer, added glycerin, and sodium phosphate with glycerin. This study of tone reproduction had been tested 5 times to get accuracy by PS platesusing kodak CCG C-3, KMS. The test result of tone reproduction of presensitized offset plates can be summarized as follows ; major compositions in positive type plate developer were Na, Si, K and P, developability were increased by Sio2/NaO2 ratio in positive type plate developer. Shelf life can be kept by add glycerin to positive type plate developer. Tone reproduction were improved by sodium phosphate due to buffer action while shelf life can be kept by add glycerin in positive type plate developer.