• Applied Biological Chemistry
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• v.37 no.4
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• pp.259-265
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• 1994

To investigate the effects of protein concentration, heat treatment and pH on the foaming properties of sodium caseinate, surface tension, apparent viscosity, turbidity, foaming ability and foam stability at 1.0, 3.0, 5.0, 7.0 and 10.0% (W/V), at 55 and $65^{\circ}C$ and at pH 6.0, 7.0 and 8.0 were examined. The conditions of protein concentrations for the foaming abilities were $3.0{\sim}7.0%$ (W/V). Foam stabilities of heated sodium caseinates were worse than those of unheated sodium caseinates (control) at pH6.0 and 7.0 (p<0.05), while the heated one were better than the unheated at pH 8.0, 10.0% concentrations (p<0.05). Also foam stabilities of sodium caseinate at pH 6.0 were higher than those at pH 7.0 and 8.0. Foaming ability and foam stability were inconsistently effected by changing protein concentration, heat treatment and pH.

• Korean Journal of Food Science and Technology
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• v.45 no.4
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• pp.526-529
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• 2013

This study was conducted to evaluate the disinfection effects of Staphylococcus aureus, and Escherichia coli treated with 461-nm LED and pH 5 at $15^{\circ}C$ for 10 h. S. aureus strains were decreased by about 4 log CFU/mL after 461-nm LED irradiation treatment alone for 10 h. E. coli strains were inactivated by irradiation. However, when microorganisms were subjected to a combined treatment of 461-nm LED and pH 5, both strains were inactivated by irradiation for 7 h. The highest D-value was 5.05 h for S. aureus ATCC 27664 and the lowest D-value was 1.39 h for E.coli O157: H7 ATCC 35150 (p<0.05) with 461-nm LED irradiation. For the combined treatment (461-nm LED and pH 5), the highest D-value was 1.58 h for S. aureus ATCC 19095, whereas the lowest D-value was 0.83 h for S. aureus ATCC 27664 (p<0.05). These data showed that bactericidal effects of a combination of pH 5 with 461-nm LED irradiation were enhanced compared to 461-nm LED irradiation alone.

• 한국전기화학회:학술대회논문집
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• 2004.04a
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• pp.32-32
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• 2004

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.1
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• pp.12-22
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• 1988

The effects of pH and Aluminum treatment on the seedling growth were examined with 11 cultivar under three levels of pH in nutri-culture.. Growth and yield responses of soil pH and nitrogen fertilization were also studied with five cultivars under 3 levels of soil pH and 3 levels of nitrogen application in the field experiment. The effect of pH on the seedling growth was not significant, but Aluminum treatment significantly decreased the seedling growth in nutri-culture except Dusan ＃12. Chlorophyll contents of leaves, dry weight of plants, culm length, spike numbers per unit area, grain numbers per spike, grain weight, and yield were decreased as the decrease of soil pH, and thus highly significant correlation between soil pH during barley growth and yield was observed in all cultivars examined. The stable cultivars to different soil pH with high yield was not found although the decreases of yield were different with cultivars. The increase of nitrogen fertilization significantly increased the nitrogen and chlorophyll contents of leaves, and dry weight of plants, while showed a little effects on the culm length, spike number per unit area, grain number per spike, grain weight and yield. The yield was significantly correlated with culm length, dry weight of plants, grain numbers per spike and 1000 grain weight at each pH levels.

• Journal of Environmental Health Sciences
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• v.41 no.6
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• pp.438-448
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• 2015

Objectives: This study was performed to examine the effects of storage time and temperature and their interaction on the hygienic quality parameters of shell eggs. Methods: Eggs from 40-week-old Hy-Line Brown hens were sampled immediately after being laid and subjected to storage periods of four weeks at a refrigerated temperature ($4-5^{\circ}C$) or room temperature ($13.0-19.7^{\circ}C$). Interior/exterior qualities were examined every one week. Results: Weight loss was 2.4-3.1%. The initial specific gravity of the eggs was maintained until one week at both temperatures. Air cell size exceeded 4 mm when stored for one week at room temperature, and two weeks at refrigerated temperature. Albumen index and Haugh unit were significantly decreased at both temperatures after one week (p<0.001). Rapidly increased pH of the albumen with one week of storage was observed, regardless of temperature (p<0.001). Extension of the storage for up to four weeks at room temperature resulted in remarkable deterioration of eggshell quality and instrumental color as redness (a). Air cell size, albumen and yolk indices, Haugh unit, pH of albumen and yolk were found to be influenced by storage time and temperature (p<0.001). Interaction effects between storage time and temperature were also significant for air cell size, pH of albumen and yolk (p<0.001). Conclusion: The results suggest that air cell size and pH of albumen and yolk were important parameters influenced by storage time and temperature in shell eggs. Storage time was more influential for air cell size, and temperature for the pH of yolk. Both variables almost equally influenced the pH of albumen.

• Journal of Industrial Technology
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• v.20 no.A
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• pp.45-50
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• 2000

A submerged cultivation of Ganoderma lucidum was carried out in an air-lift fermenter system, and the effects of different pH processes on extracellular branched ${\beta}$-1,3-glucan(EPS) production and mycelial growth(MDW) were investigated. The controlled pH process improved the production of branched ${\beta}$-1,3-glucan and biomass in comparison to the uncontrolled pH process. However, the maximum production of branched ${\beta}$-1,3-glucan were obtained by the bi-staged pH process. From these results, we confirmed that the bi-staged pH process was the most effective for improving the production of branched ${\beta}$-1,3-glucan from submerged culture of G. lucidum.

• Journal of Nutrition and Health
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• v.26 no.8
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• pp.998-1005
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• 1993

This study was attempted to investigate the effects of enzymatic modification of milk protein with Meju protease on its acid clotting and digestibility. The proteases used in this study were isolated from Meju(fermented soybeans) and had specific acticity of 250 units/mg protein at pH 7.0. These proteases were found to be at least 3 different isoenzymes of different pH optima(pH 4.0, 6.0, 10.0). The optimum temperature was 5$0^{\circ}C$. Hydrolyzed skim milk showed 30.5% degree of hydrolysis for 1 hr. and 36.4% degree of hydrolysis for 3.5 hrs. of protease treatment at pH 7.0. Upon acidification to pH 4.0, skim milk produced large and dense coagulum, but the coagulum was getting smaller by protease treatment. Generally, digestability of skim milk at pH 4.0 was lower than pH 2.0. At pH 4.0, native skim milk and control group had problem with hydrolysis of skim milk protein. Among protease treated groups, 1 hour treated skim milk was most effectively hyrolyzed at pH 4.0.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.267.2-267.2
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• 2013

In the citrate reduction method of gold nanoparticle (AuNP) synthesis, pH of the reaction mixture can have a considerable impact on the size and size distribution of AuNPs. In this work, effects of pH variation upon the size and its distribution were examined systematically. As the initial pH was change from 5.5 to 10.5, it showed an optimal pH around 7.5. At this pH, both of the size and the size distribution showed their minimum values, which was verified by transmission electron microscopy and UV-vis spectroscopy. This occurrence of optimal pH was discussed with the results of in situ monitoring pH during the reaction of AuNP synthesis.

• Korean Journal of Environmental Biology
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• v.20 no.1
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• pp.78-84
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• 2002

The effects of light and darkness on stomatal aperture and guard cell apoplastic pH in the intact leaf and in the isolated epidermal strips of Commelina communis have been investigated. Stomata in the intact leaf opened wide in the light. In contrast, stomata in the isolated epidermal strips did not respond clearly to light. To eucidate the relationship between the stomatal aperture and the guard cell apoplastic pH, apoplastic pH was measured. In the light the guard cell wall of intact leaf was acidified by pH 1.9 units, falling from pH 7.3 to pH 5.4 in the first 10 minutes. On the contrary, apoplastic pH of isolated epidermal strips changed slowly from pH 7.3 to pH 6.9 at 20 min. Stomata in the intact leaf closed rapidly in the dark. On the other hand, stomata in the isolated epidermal strips failed to close in dark. There was a slow increase in apoplastic pH on transfer to the dark after incubation for 1.5 h in the light and the level observed before the experiment was regained after around 40 min. When the isolated epidermal strips were transferred to the dark, apoplastic pH maintained a uniform level of around pH 7.2-7.4. These results indicate that the mechanism of stomatal opening and closing from isolated epidermal strips and intact leaves could be different.

• Journal of Periodontal and Implant Science
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• v.42 no.6
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• pp.185-195
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• 2012

Purpose: (-)-epigallocatechin-3-gallate (EGCG) has been reported to exert anti-inflammatory and antibacterial effects in periodontitis. However, its exact mechanism of action has yet to be determined. The present in vitro study evaluated the anti-in-flammatory effects of EGCG on human periodontal ligament fibroblasts (hPDLFs) and human periodontal ligament stem cells (hPDLSCs) affected by bacterial lipopolysaccharide (LPS) extracted from Porphyromonas gingivalis. Methods: hPDLFs and hPDLSCs were extracted from healthy young adults and were treated with EGCG and/or P. gingivalis LPS. After 1, 3, 5, and 7 days from treatment, cytotoxic and proliferative effects were evaluated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and bromodeoxyuridine assay, respectively. And then, the gene expressions of hPDLFs and hPDLSCs were observed for interleukin (IL)-$1{\beta}$, IL-6, tumor necrosis factor (TNF)-${\alpha}$, osteoprotegerin (OPG), receptor activator of nuclear factor kappa-B ligand (RANKL), and RANKL/OPG using real-time polymerase chain reaction (PCR) at 0, 6, 24, and 48 hours after treatment. The experiments were performed with the following groups for hPDLFs and hPDLSCs; 1) No treat, 2) EGCG alone, 3) P. gingivalis LPS alone, 4) EGCG+P. gingivalis LPS. Results: The 20 ${\mu}M$ of EGCG and 20 ${\mu}g/mL$ of P. gingivalis LPS had the lowest cytotoxic effects, so those concentrations were used for further experiments. The proliferations of hPDLFs and hPDLSCs increased in all groups, though the 'EGCG alone' showed less increase. In real-time PCR, the hPDLFs and hPDLSCs of 'EGCG alone' showed similar gene expressions to those cells of 'no treat'. The gene expressions of 'P. gingivalis LPS alone' in both hPDLFs and hPDLSCs were highly increased at 6 hours for IL-$1{\beta}$, IL-6, TNF-${\alpha}$, RANKL, and RANKL/OPG, except the RANKL/OPG in hPDLSCs. However, those increased gene expressions were down-regulated in 'EGCG+P. gingivalis LPS' by the additional treatment of EGCG. Conclusions: Our results demonstrate that EGCG could exert an anti-inflammatory effect in hPDLFs and hPDLSCs against a major pathogen of periodontitis, P. gingivalis LPS.