• Journal of Life Science
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• v.21 no.11
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• pp.1565-1572
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• 2011

Eye-specific lactate dehydrogenase (EC 1.1.1.27, LDH) $C_4$ isozyme in the eyes of greenlings (Hexagrammos otakii) was successfully purified by affinity chromatography and continuous-elution electrophoresis. The molecular weight of the purified eye-specific LDH $C_4$ isozyme was 154.8 kDa, as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Optimal pH for enzymatic reaction of the eye-specific LDH $C_4$ isozyme was pH 8.5. $K^{PYR}_m$ value of the purified eye-specific LDH $C_4$ isozyme was $1.88{\times}10^{-5}$ M using pyruvate as a substrate. These results indicate that we must consider pH when measuring eye-specific LDH $C_4$ isozyme activity. The eye-specific LDH $C_4$ isozyme had a higher binding affinity for the substrate as a pyruvate than LDH A4 isozyme. Antibodies produced against the purified eye-specific LDH $C_4$ isozyme may be used in the diagnosis of several human diseases and in comparative physiological studies of fishes.

• Applied Biological Chemistry
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• v.20 no.1
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• pp.26-32
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• 1977

The multiple 7S globulins composed of two fractions (A and B) in the electrophoresis with Davis' method were isolated at different stages of the soybean seed development. Electrophoresis of their subunits liberated in PAWU solvent [phenol-acetic acid-water (2 : 1 : 1) solution plus 5M urea] yielded 4 major bands. Observation of both the electrophoretic bands of the multiple 7S fractions(7S-A and 7S-B) and those of their subunits was suggestive of a similarity of the subunit pattern between two 7S fractions. The two fractions in multiple 7S globulins were isolated with DEAE-Sephadex A-50 column$(2.0{\sim}100cm)$ chromatography. They were separated into 2 fractions in a linear gradient concentration of 0.28 to 0.40M NaCl with phosphate buffer (pH 7.8) containing 10mM ${\beta}-mercaptoethanol$(ME). The isolated protein was dissociated into subunits with two different solvent systems; in PAWU solvent and in Tris-HCl buffer(pH 8.0) containing 1% sodium dodecyl sulfate (SDS) and 40mM ME. The dissociated subunits were subjected to electrophoresis in PAWU-treated 7.5% acrylamide gel and in 1% SDS-treated 5.6% acrylamide gel. In PAWU gel electrophoresis, total 7S globulin was separated into 5 major bands, two of which were occupied in common by two 7S fractions(7S-A and 7S-B). In SDS gel electrophoresis, total 7S globulin was separated into 7 major bands, three of which were overlapped with the subunit of the two 7S fractions. The above results alluded us to the presence of a common and/or similar subunit between the multiple 7S globulins.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.6
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• pp.1032-1038
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• 2008

This study was conducted to develope carbohydrate-based fat replacement for use in the preparation of non-(trans) fatty acid and low-caloric bread. Characteristics such as leavening height of batter, pH, titratable acidity, specific volume, sensory evaluation, shelf life and texture change of bread made using 11 types of carbohydrate-based fat replacements were measured. The 11 carbohydrate-based fat replacers (No. $1{\sim}11$) were prepared using maltodextrin as a base, and different ratios of calcium sulfate, ascorbic acid, sodium stearoyl lactylate and methyl cellulose. The pH was lowered and the total titratable acidity was increased after four hours of fermentation in the control and the samples of dough that contained the fat replacement. In addition, the leavening height of the control was 5.0cm (maximum) after two hours of fermentation and 4.6 cm after four hours of fermentation, which was similar to the heights observed when No.$9{\sim}11$ were evaluated. When the specific volume of the bread was evaluated, the 3% of fat replacement No. 10 produced the best results. When taste was evaluated, there was no significant difference between the control and the bread produced using 1% No. 10, however, there was a significant difference between the control and all samples that contained 2% or more of the fat replacement. Furthermore, the addition of a greater concentration of the fat replacer resulted in a greater moisture. However, there were no significant differences in the color of the control and any of the samples. Additionally, measurement of the firmness of the bread during four days of storage at $25^{\circ}C$ revealed that it decreased as the concentration of fat replacer increased. In addition, the sample that contained 3% of sample No. 10 showed a firmness of 18kgf after three days of storage, while the control showed a firmness of 18kg after two days, which indicates that the degradation of the bread that contained the fat replacer was delayed by one day. The bread made using fat replacers was found to have a better taste, flavor, color, texture and firmness than the control, and the best results were observed in response to the addition of 3% of replacement No. 10. The results of this study will be useful in the production of non-(trans) fatty acid, low caloric bread.

• Journal of the Korean Chemical Society
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• v.7 no.2
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• pp.91-95
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• 1963

The basic studies of adsorption characteristics of collector on monazite were made by electrophoretic measurement and by determination of the adsorption of some typical flotation collectors. By above measurements made on monazite, it is concluded that $H^+\;and\;OH^-$ are identified to act as potential determining ions and thus the electrical properties of monazite is controlled by the pH of the solution. Therefore, anionic collectors are adsorbed on positively charged surfaces and cationic collectors on negatively charged surfaces, which in turn controls the effective flotation condition with respective collectors for this mineral. These results have been correlated with its flotation behavior obtained by Hallimond tube test.

• Food Science and Preservation
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• v.19 no.2
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• pp.216-222
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• 2012

The optimum annealing conditions of corn starch slurry were studied for RS4 type resistant starch production by phosphorylated cross-linking. When a corn starch slurry was cross-linked by using phosphate salts (STMP/STPP mixture) in the presence of 0.9%, 1.2% and 1.5% NaOH/st.ds, a high concentration of NaOH resulted in a rapid increase of the RS contents at the early reaction stage. However, similar RS contents were obtained after 12 h of cross-linking regardless of NaOH concentrations. The annealing treatment was conducted under various conditions such as pH between 2-10, temperature $40-60^{\circ}C$, time 0-14 h followed by phosphorylated cross-linking. The lower slurry pH was for the annealing treatment, the higher RS contents were obtained after cross-linking. When the slurry annealed for various period of time and temperature, a maximal amount of RS was formed after 2 h of annealing at $50^{\circ}C$ of annealing temperature of the starch slurry (pH 2.0). Therefore, an optimal annealing conditions at pH 2.0 and $50^{\circ}C$ for 2 h were proposed under the cross-linking conditions of sodium sulfate 10%/st.ds, NaOH 1.2%/st.ds and 12 h of the reaction time. The RS contents were linearly increased with the increase of phosphate salt addition. The RS4 prepared under the optimal conditions contained RS 72.3% and its phosphorus content was 0.36%/st.ds, which was below the limit (0.4%/st.ds) of modified starch by Korea Food Additives Code.

• The Korean Journal of Zoology
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• v.33 no.1
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• pp.63-69
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• 1990

To study the follicular atretic mechanism in mammalian ovary, the medium-sized (3.0-6.0mm) follicles of porcine ovary were morphologically classified as nonnal and atretic. Steroid concentrations in the follicular fluid were analyzed by radioimmunoassay, and the proteins in that fluid were electrophoretically separated. Concentrations of progesterone in the atretic follicular fluid of follicular phases were higher than those of normal ones (p < 0.05). Concentrations of testosterone were high in normal luteal and atretic follicular-phases follicles. The concentrations of estradiol remained significanily lower in atretic follicular-phases follicles than normal. After sodium dodecyl sulfate-polyacrylamide gel electrophoresis of follicular fluid proteins, four kinds of proteins (20K, 32K, 33K, 38K) were detected, and those proteins were not present in sera. According to the ovarian cycle, proteins of MW of 112K and 141K were identified. In atretic follicular fludies, MW of 23K and 24K were specifically detected. From the above results, we can conclude that, as ovarian cycle changes, steroid contents and protein composition in atretic follicular fluid are different from the normal developing follicular fluid. To further understand the physiologic roles of the proteins present in the atretic follicular fluids, these proteins need to be characterized and identified.

• Journal of Korean Society on Water Environment
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• v.32 no.5
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• pp.442-449
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• 2016

The goal of this study is to provide basic data to establish a foundation for the provision of safe drinkable water. The raw water of natural mineral water was analyzed to determine the quantities of anions (F^-, Cl^-, NO_3-N^-, and SO₄^2- ) and cations (Ca²⁺, K⁺, Mg²⁺, and Na⁺) during the former and latter half of 2016. Analysis of the current quality of the raw water of natural mineral water among domestic manufacturers showed average anions contents of 0.46mg/L of fluorine, 8mg/L of chlorine ion, 1.5mg/L of nitrate nitrogen, and 12mg/L of sulfate ion. While the fluorine content was greater than the water quality criterion of 2.0mg/L at four points, the fluorine level was overall stable. The average cations contents included 21.3mg/L of calcium, 1.0mg/L of potassium, 3.4mg/L of magnesium, and 9.6mg/L of sodium. The chemical characteristics were compared among the major ions, and the results are presented in a piper diagram. The content ratio of cations was in the order of Ca²⁺> Na⁺>Mg²⁺>K⁺, whereas that of anions was in the order of SO₄^2->Cl^->NO_3-N^->F^-. While the cations were slightly scattered, the anions were generally concentrated except for at a few points. The Ca-Na-HCO₃ type was dominant overall in water sources from diorite, gneiss, and granite, while the Na-Mg-Ca-HCO₃-Cl type was dominant in basalt sources. Mineral water manufacturers source their water under various conditions, including in-hole casing, excavation depth, and contact state of bedrock; even within the same rocky area, some differences in the water quality type can occur. When the depth of the water source was taken into account, the mean anions contents of F^-, Cl^-, NO_3-N^-, and SO₄^2- were similar, with no significant differences according to depth. Of the cations, K⁺ and Na⁺ showed no significant differences across all the tubular wells, whereas Ca²⁺ and Mg²⁺ decreased in content with depth.

• Korean journal of food and cookery science
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• v.7 no.3
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• pp.13-20
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• 1991

This study was performed to examine the electrophoretic properties of Job's tears (Yulmoo: Coix lachryma-jobi L. var. Ma-yuen Stapf. & Yeomjoo: Coix lachryma-jobi L.) proteins. Albumins, globulins, gliadins and glutelins were extracted from the polished Yulmoo and brown Yeomjoo by the modified Osborne method. For a comparison, rice proteins were extracted and fractionated by the same method. The relative proportions of protein fractions were 17.4 : 19.6 : 55.2 : 7.7% in polished Yulmoo, 12.6 : 62.2 : 4.2 :21.0% in brown Yeomjoo and 14.2 : 57 4 : 0.77 : 27.8% in rice, in the order of albumis, globulins, gliadins and glutelins. Polyacrylamide gel electrophoresis (PAGE) and SDS-polyacrylamide gel electrophoresis (SDS-PAGE) were peformed to identify the subfractions of each protein fraction extracted from polished Yulmoo, brown Yeomjoo and rice. The electro-phoregrams of polyacrylamide gel electrophoresis showed that the same fractions of both polished Yulmoo protein and brown Yeomjoo protein had very similar electrophoretic patterns to each other respectively, but there were significant differences in the patterns between Job's tears proteins and rice proteins.

• Food Science of Animal Resources
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• v.22 no.3
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• pp.259-266
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• 2002

The egg shell membrane degrading isolated from soil was identified as Bacillus licheniformis by 16S rDNA identification method. A keratinase was isolated from the Baciilu licheniformis culture. DEAE-cellulose ion-exchange and Sephadex C-75 gel chromatograhies were used to purify the enzyme. The specific activity was increased 17.3-fold by the purification procedures. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis and Sephadex G-75 chromatography indicated that the purified keratinase was monomeric and had a molecular weight of 65 kDa. The enzyme showed optimum activity at pH 9.0, and was stable above pH 9.0. The optimum temperature was 50$\^{C}$ and the enzyme was stable in the temperature ranges from 20$\^{C}$ to 50t. By the addition of 1 mM and 10 mM FeSO4, the activities of the enzyme were increased to 111$\pm$4.6% and 133$\pm$3.79%, respectively. The keratinase was an alkaline serine pretense because it was inhibited only by phenylmethylsulfonylfluorice (PMSF).

• Korean Journal of Materials Research
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• v.8 no.2
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• pp.135-140
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• 1998

Drag reduction produced by dilute solution of water soluble ionic polymer-surfactant complex under turbulent flow in a rotating disk apparatus(RDA) was investigated in this study. Three different molecular weights of polyacrylic acid(PAA) were adopted as drag reducing additives, and distilled water was used as a solvent. Experiments were undertaken to observe the dependence of drag reduction on various factors such as polymer molecular weight, molecular expansions and flexibility, rotating speed of the disk and polymer concentration. Specific considerations were put on conformational difference between surfactant and polymer, and effect of pH on ionic polymer possessing various molecular conformation through pH. The complex of ionic polymer and surfactant(Sodium Dodecyl Sulfate) behaves like a large polyelectrolyte. Surfactant changes the polymer conformation and then increases the dimension of the polymer. The radius of gyration, hydrodynamic volume and relative viscosity of the polymer-surfactant system are observed to be greater than those of polymer itself. Such surfactant-polymer complex has enhanced drag reduction properties.