• The korean journal of orthodontics
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• v.25 no.2 s.49
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• pp.223-233
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• 1995

The purpose of this study was to evaluate the effects of surface conditioning with $10\%$ polyacrylic acid, etching with $38\%$ phosphoric acid, and polishing with a slurry of pumice on shear bond strengths of light-cured glass ionomer cement, chemically cured glass ionomer cement, and a composite resin to enamel, and to observe the failure patterns of bracket bondings. Shear bond strengths of glass ionomer cements were compared with that of a composite resin. Metal brackets were bonded on the extracted human bicuspids after enamel surface treatments, and samples were immersed in the $37^{\circ}C$ distilled water bath, and shear bond strengths of glass ionomer cements and a composite resin were measured on the Instron machine after 24hrs passed, and the deboned samples were measured in respect of adhesive remnant index. Scanning electron micrographs were taken of enamel surfaces after various treatments. The data were evaluated and tested by ANOVA and Duncan's multiple range test, and those results were as follows. 1. Shear bond strength of light-cured glass ionomer cement showed statistically higher than that of chemically cured glass ionomer cement. 2. Shear bond strengths of light-cured and chemically cured glass ionomer cements to enamel treated with $10\%$ polyacrylic acid and $38\%$ phosphoric acid showed statistically higher than those with a slurry of pumice. 3. According to scanning electron micrographs, enamel surface conditioned with $10\%$ polyacrylic acid is slightly etched and cleaned, that etched with $38\%$ phosphoric acid is severely etched, and that polished with a slurry of pumice is irregulary scretched and not completely cleaned. 4. After debonding, light-cured glass ionomer cement to enamel treated with $10\%$ polyacrylic acid showed less residual materials on the enamel solace than composite resin to enamel etched with $38\%$ phosphoric acid. 5. There was no significant difference in the shear bond strength of light-cured glass ionomer cement to enamel treated with $10\%$ polyacrylic acid and that of composite resin to enamel etched with $38\%$ Phosphoric acid.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.2
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• pp.235-242
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• 2017

In this study, we evaluated the polyphenol content, flavonoid content, antioxidant and biological of 70% EtOH extract and its fractions (dichloromethane, ethyl acetate and water) of the plant Chrysanthemum indicum L. (CI) belonging to family chrysanthemum. antioxidant activity was determined 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), and superoxide scavenging activity. The biological activity tests included measurement of ${\alpha}$-glucosidase and PTP1B. The results show that content of polyphenol and flavonoid in 70% EtOH of CI 30.20 mg and 31.58 mg, respectively. Among the different samples, ethyl acetate (EA) fraction showed the highest level of polyphenol (87.87 mg) and flavonoid (65.12 mg). The DPPH, ABTS and superoxide dismutase(SOD) antioxidant assay of EA fraction showed 93.84%, 93.38% and 84.68% inhibition respectively. The EA fraction also showed the highest antioxidant activity compared to 70% EtOH extract and other fractions. EA fraction ($20{\mu}g/mL$) showed the highest 30.29% and 99.24%, respectively compared to other samples. The results of this study show that the EA fraction contained more antioxidant and antidiabetic components than 70% EtOH extract and other fractions. In conclusion, we believe that CI may be useful natural antioxidant and functional material.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.1
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• pp.1-6
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• 2011

This study was conducted to evaluate the antioxidant activity of liquid beni-koji (LBK), 70% ethanol extracts of beni-koji (EEB) and water extract of Hwangki (WEH). The yields of freeze dried powder of LBK, EEB and WEH were 32.17 g/L, 23.61 g/kg and 196.33 g/kg, respectively. Electron donating ability at 1% (w/v) of LBK, EEB and WEH were 82.67%, 15.71% and 8.60%; reducing power (OD700) were 2.06, 1.64 and 0.45, respectively. SOD-like activities were 24.32%, 11.11%, and 17.94%; nitrite scavenging activities were 74.92%, 72.31% and 31.83%, respectively. TBARS (%) were in order of LBK (69.65%)> EEB (67.32%)> WEH (4.42%). Electron donating ability at 1% (w/v) of EEB : WEH (1:1, w/w. EW), LBK : WEH (1:1, w/w. LW), EEB : LBK: WEH (1:1:1, w/w. ELW) were 14.58%, 60.66% and 20.42%; reducing power ($OD_{700}$) were 1.06, 2.01 and 1.71; SOD-like activities were 18.50%, 26.94% and 18.25%, respectively. While nitrite scavenging activities and TBARS (%) of ELW was higher than those of other materials. Total polyphenol content of LBK, EEB, WEH, EW, LW, ELW were 3.98%, 3.61%, 3.02%, 3.23%, 3.46% and 3.38%; total flavonoid content were 0.89%, 3.91%, 0.30%, 2.59%, 0.46% and 2.33%, respectively. In conclusion, this study provides experimental evidence that mixture of LBK, EEB and WEH could be used as a source of antioxidant ingredients in the food industry.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.3
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• pp.434-441
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• 2015

To develop dough methods for improving bread making properties of Korean wheat flour, straight dough methods (SDM) and dough and sponge methods (DSM) were applied. The bread making properties such as weight of bread, specific volume, baking loss, crumb color, and texture were analyzed. In comparison of flour properties between Korean wheat flour and imported wheat flour by Farinograph, Korean wheat flour showed less gluten network form ability than imported wheat flour. The dough making method affected bread quality such as weight of bread, specific volume, and baking loss. SDM had a more desirable effect on bread quality. Crumb color was lighter in bread made with Korean wheat flour compared to imported wheat flour, whereas dough making method did not affect crumb color. In consumer acceptance analysis, bread made by DSM showed higher consumer acceptance than that made by SDM. Regarding physicochemical changes during storage, bread made by SDM using Korean wheat flour showed higher chewiness, brittleness, and hardness than that made by imported wheat flour. However, bread made by DSM showed similar chewiness as bread made by SDM using imported wheat flour. The bread making properties of bread made by DSM is improved versus that of bread made with Korean wheat flour.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.1
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• pp.52-60
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• 2016

The biological activity of polysaccharide is greatly influenced by polysaccharide structure and molecular distribution. Here, we developed a rapid and convenient isolation method for fractionating polysaccharides with different characteristics and optimized it using a polysaccharide mixture from Korean persimmon leaves. A crude polysaccharide mixture, persimmon leaves-enzyme (PLE) fraction, was isolated from persimmon leaves digested with pectinase and ethanol precipitation. The PLE fraction was further fractionated with a serially diluted ethanol solution (ethanol : deionized water=4:1, 2:1, 1.5:1, 1:1, and 0.5:1) to produce 10 subfractions (five precipitate fractions labeled from PLE-4 to PLE-0.5 and five supernatant fractions labeled from PLE-4S to PLE-0.5S). HPLC analysis indicated that PLE-4 and -2 consisted of diverse polysaccharides, whereas PLE-1.5, -1, and -0.5 contained high molecular weight (MW) polysaccharides. The fractions from PLE-4 to PLE-1 were mostly composed of 13 different characteristic sugars in rhamnogalacturonan (RG) I and II, and the sugars contained an arabino-${\beta}$-3,6-galactan moiety. However, PLE-0.5 did not contain RG-II or ${\beta}$-arabino-3,6-galactan. Treatment of macrophages with fractions PLE-1.5S and PLE-1S led to a $10{\mu}g/mL$ increase in interleukin (IL)-6 production, whereas treatment with PLE-4S and PLE-2S fractions composed of low MW polysaccharides resulted in reduced levels of IL-6. These results indicate that this isolation method may be useful for the rapid and convenient fractionation of bioactive RGs from polysaccharide mixtures with various properties.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.1
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• pp.57-66
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• 1988

As a method of utilization of sardine, the processing conditions of the sardine sauce extracts and the taste compounds of products were investigated. To prepare the sardine sauce extracts, chopped sardine was mixed with $1\%$, onion powder, $1\%$ garlic powder, $1\%$ red pepper powder, loft koji and $50\%$ water, and then hydrolyzed under different conditions of hydrolysis. The optimum conditions for hydrolysis were $55^{\circ}C$, 6 hours, pH 6.5-7.0. After hydrolysis, the hydrolysates were heated at $100^{\circ}C$ for 20 minutes with $5\%$ soybean protein isolate for inactivation of enzymes and improvement of bitter taste of the hydrolysates. Finally, $10\%$ salt was added to develop the characteristic taste of sauce extracts. The major taste compounds of the products were free amino acids, non-volatile organic acids and nucleotides and their related compounds. The major free amino acids in the products were arginine, histidine, lysine, glutamic acid, phenylalanine, leucine and alanine. The contents of these free amino acids were in the range of $68.2\%\;to\;69.9\%$ of the total free amino acids of products. The major non-volatile organic acids ill the products were lactic acid and $\alpha-ketoglutaric$ acid which occupied more than $95\%$ of total non-volatile organic acids. The contents of free amino acids, non-volatile organic acids and nucleotides and their related compounds were not changed during storage. Total creatinine, betaine and TMAO were seemed to act an auxiliary role in taste of the products. Judging from the results of chemical experiments and sensory evaluation, the product prepared with koji and soybean protein isolate was excellent as seasoning materials.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.3
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• pp.666-671
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• 2003

Dental caries are the most commonly occurring chronic diseases in the dental field. Because of increasing sugar consumption and extension of average human life, these diseases are widely found all over the world as the most typical cause for a person to lose a tooth. Therefore, the development of more effective, substantial and safe preventive agents against dental caries is strongly required. Streptococcus mutans is known as the causative bacterial playing the most important role informing plaque and it is being noticed as major causative bacteria of dental caries. The present study was designed to investigate the effect of Asarum sieboldii Miquel(Aristolochiaceae) extracts on the growth, acid production, adhesion, and insoluble glucan synthesis of Streptococcus mutans(S. mutans). Both methanol and aqueous extracts showed concentration dependent inhibitory activity against the growth and acid production of S. mutans, and produced significant inhibition at the concentration of 100, 1,000 and 2,000 μg/ml compared to the control group(p<0.05 - p<0.01). The extracts markedly inhibited S. mutans adherence to HA treated with saliva, and cell adherence was repressed by more than 50% at the concentration of 10 μg/ml and complete inhibition was observed at the concentration of 2,000 μg/ml. On the activity of glucosyltransferase which synthesizes water insoluble glucan from sucrose, methanol and aqueous extracts showed more than 70% inhibition over the concentration of 1,000 μg/ml. Hence, we conclude that Asarum sieboldii might be a candidate of anticaries agent.

• Journal of Life Science
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• v.20 no.9
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• pp.1402-1408
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• 2010

The effects of rice hull (RH) powder on the anticarcinogenic activity of submerged-liquid cultures of Agaricus blazei Murill (AB) were assessed for mouse ascites cancers induced by mouse Sarcoma S-180 (S-180) cancer cells. Optimal growth of AB mycelia in the basal liquid culture medium, containing soybean meal, was achieved by culturing at $25^{\circ}C$ for 5 days, when evaluated by $\beta$-glucan content, Brix, and mycelial weight, relative to other culture conditions. Hot-water extract (HWE) of the submergedliquid culture of AB mycelia grown at $25^{\circ}C$ for 5 days exhibited a stronger anticarcinogenic activity, relative to HWE from other culture conditions. No such effects were obtained from AB mycelial cultures by alternative temperature-controlling cultures. Both cytotoxicity for S-180 cells and anticarcinogenic potentials for mouse ascites cancer of the HWE from AB mycelia grown in the basal medium containing 1% RH powder for 5 days at $25^{\circ}C$ were significantly (p<0.05) enhanced, relative to HWE from the AB mycelia culture of the basal medium without RH powder. These results indicate that HWE of submerged-liquid culture of AB mycelia, incubated in media containing 1% RH powder at $25^{\circ}C$ for 5 days, enhanced anticarcinogenic activity against S-180 cell-induced mouse ascites cancer, and suggest that RH powder is an excellent ingredient for the improvement of the anticarcinogenic potentials of the submerged-liquid culture of mushroom mycelia.

• Clean Technology
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• v.20 no.3
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• pp.232-240
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• 2014

The significance of thermoplastic polyolefin polypropylene (PP) lies in its potential to replace polyvinyl chloride (PVC), the most widely used material for automobile interiors (door trim, dash board), which discharges harmful compounds in certain conditions. Another benefit of PP (0.855 amorphous - 0.946 crystalline $g/cm^3$) is its low density compared to that of PVC ($1.1-1.45g/cm^3$), which reduces vehicle weight. Market demand for eco-friendly water-based adhesive/coating material is rising significantly as a substitute for solvent-based adhesive/coating material which emits VOC and causes harmful working conditions. Under such context, in this study, a series of eco-friendly waterborne polyurethane-urea primer (a paint product that allows finishing paint to adhere much better than if it were used alone) for hydrophobic PP were prepared from different mix of DMPA content, NCO/OH molar ratio, various wt% of silicone diol and various soft segment content, among which DMPA of 21 mole %, NCO/OH molar ratio of 1.2, modified silicone diol of 5 wt% and soft segment content of 73 wt% led to good adhesion strength. Additionally, the incorporation of optimum content of additives (0.5 wt% dispersing agent, 0.5 wt% levelling agent, 1.5 wt% antifoaming agent, 3.0 wt% matting agent) into the optimum waterborne polyurethane-urea also enabled good stability, levelling, antifoaming and non-glossy.

• Korean Journal of Agricultural Science
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• v.10 no.2
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• pp.354-364
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• 1983

Confonmation of (Z)-cinnamonitrile have been studied by molecular orbital theoretically using extended Huckel theory(EHT) and CNDO/2 molecular orbital calculation methods. The results indicate that the stability of conformation is(Z)-gauch>(Z)-planar. The rate constants for alkalie hydrolysis of cinnamonitrile at pH 7.0-14.0 range have been determined by ultra-violet spectrophotometry in 50% methanol at $25^{\circ}C$ and the following rate equation which can be applied over wide pH range was obtained; $${\therefore}k=({\frac{1.41{\times}10^{-14}+1.21{\times}10^7/[H_3O^+]}{2.65{\times}10^{-7}+1.64/[H_3O^+]})+9.14{\times}10^9/[H_3O^+]$$ The rate equation reveals that, at pH 7.0-10.0, the reaction is initiated by the addition of water molecule to unsaturated cabon-carhon double bond of cinnamonitrile and ${\alpha}C-{\beta}C$ bond scission follow subsequently in neutral and alkalie media. At pH 12.0-14.0, in strong alkalie solution, that so-called Michael type nucleophilic addition that the over-all rate constants is only dependent upon the concentration of hydroxide ion occurs competitively and are very complicated. Hence, the reaction mechanism of alkalie hydrolysis of cinnamonitrile which did not carefully before can be fully explained.