• Journal of Life Science
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• v.8 no.5
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• pp.614-621
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• 1998

An extracellular inulinase from Penicillium sp. which isolated from soil sample was purified to a single protein th-rough ammonium sulfate fractionation, DEAE-Sephacel ion exchange chromatography and Toyopearl HW 65 F gel filtration. The temperature and pH for the enzyme reaction were around 6$0^{\circ}C$ and 4.0, respectively. The enzyme was stable at 3$0^{\circ}C$-5$0^{\circ}C$ and in the pH range of 4 to 5. $CuCl_2$, $HgCl_2$ and EDTA inhibited the enzyme activity strongly. By contrast, $MnCl_2$ and $CaCl_2$ activated the enzyme activity. The molecular weight of the purified enzyme was esti-mated to be 77,000 dalton by SDS-polyacrylamide gel electrophoresis. The Km values of the enzyme for inulin were calculated to be $2.2\times10^{-3}$M. TLC analysis suggested that purified enzyme is exo-type inulinase. The NH2-terminal amino acid sequences of the purified enzyme was determined to be $NH_2$-X-Glu-Ser-Tyr-Thr-Glu-Lys/Leu-Tyr-Arg-Pro.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.7
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• pp.1048-1054
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• 2014

The purpose of this study was carried out to investigate the cause of sulfur dioxide occurrence, general element composition, sulfur compounds, heavy metals, macro- & micro-minerals, and oxidation-reduction potential (ORP) following baking time course of RS (RS1, RS2, RS3, and RS4) and mudflat solar salts (MSS). Sulfur dioxide ($SO_2$) and sulfite ($SO{_3}^{2-}$) were not detected in MSS or RS. However, sulfate ($SO{_4}^{2-}$) content significantly decreased in RS (29,878.15~36,097.45 ppm) compared to that in MSS (35,601.65 ppm). ORP was 181.15 mV in MSS, and 58.55 mV in RS1. Moisture content was 9.34% in MSS and 0.00% in RS with increased NaCl (94.77~95.77%). Moisture and NaCl contents showed no significant difference in RS. Insoluble and sandy residues were higher in RS than in MSS, whereas Ca and K showed no significant difference. Mg and Cl contents were higher in RS than in MSS. Br level was higher in MSS (628.1 ppm) than in RS (512.72~586.62 ppm), but there was no significant difference in $NO_3$. Heavy metals (Pb, As, and Hg) were more abundant in RS than in MSS, but levels were still safe. These results suggest that MSS and RS may increase protection against from $SO_2$ and $SO{_3}^{2-}$.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.294.2-295
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• 2002

Methylmercury (MeHg: CH3HgCl) is a ubiquitous environmental toxicant that readily bioaccumulates in aquatic foodchains. This toxicant is most highly exposed to humans through the ingestion of contaminated food. and thus is an ongoing health concern. Thus far. MeHg has been suggested to exert its toxicity through its high reactivity to thiols of bioactive proteins. elevation in intracellular Ca2＋ concentration. and generation of reactive oxygen species. but its mechanism remains poorly understood. (omitted)

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.16 no.4
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• pp.149-156
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• 2006

For an aspect ratio (transport length-to-width) of 5, Pr = 2.89, Le = 0.018, Pe = 2.29, Cv = 1.11, $P_B$=40 Torr, solutally buoyancy-driven convection $(Gr_s=3.03{\times}10^5)$ due to the disparity in the molecular weights of the component A $(Hg_2Cl_2)$ and B (He) is stronger than thermally buoyancy-driven convection $(Cr_t=1.66{\times}10^4)$. The crystal growth rate is decreased exponentially for $2.5\;{\leq}\;Ar\;{\leq}\;5$, with (1) the linear temperature profile and a fixed temperature difference, (2) the imposed thermal profile, a fixed crystal region and varied temperature difference. This is related to the finding that the effects of side walls tend to stabilize convection in the growth reactor. But, with the imposed thermal profile, a fixed source region and varied temperature difference, the rate is increased far $2\;{\leq}\;Ar\;{\leq}\;3$, and remains nearly unchanged for $3\;{\leq}\;Ar\;{\leq}\;5$.

• Journal of Nutrition and Health
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• v.40 no.6
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• pp.500-508
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• 2007

The purpose of this study was to investigate the influence of mixed NaCl-KCl salt on sodium intake and urinary excretion of sodium and potassium. In this study, 3-day food records for pre-experimental diet and 24-hr urine collected for 2-days, 6-day experimental diet food and 24-hr urine were used to evaluate the relationship between Na metabolism. In the experimental diet food, mixed NaCl-KCl salt was added. During the pre-experimental diet period, intakes of Na and K were 178.2 mEq and 56.4 mEq, respectively. The urinary excretion of Na and K in 24-hr were 139.6 mEq, 27.7 mEq, respectively and urinary Na/K ratio was 6.6. During the experimental diet period, intakes of Na and K were 130.2 mEq and 120.4 mEq, respectively. The urinary excretion of Na and K in 24-hr were 100.2 mEq, 37.1 mEq, respectively and urinary Na/K ratio was 2.8. According to this study, it is concluded that mixed NaCl-KCl salt diet decreased the intake of Na, and increased the intake of K.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.20 no.3
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• pp.125-132
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• 2010

For typical governing dimensionless parameters of Ar = 5, Pr = 1.16, Le = 0.14, Pe = 3.57, Cv = 1.02, $Gr_s=2.65{\times}10^6$, the effects of thermo physical properties such as a molecular weight, a binary diffusivity coefficient, a partial pressure of component B on solutally buoyancy-driven convection (solutal Grashof number $Gr_s=2.65{\times}10^6$) are theoretically investigated for further understanding and insight into an essence of solutal convection occurring in the vapor phase during the physical vapor transport of a $Hg_2Cl_2-N_2$ system. The solutally buoyancy-driven convection is significantly affected by any significant disparity in the molecular weight of the crystal components and the impurity gas of nitrogen. The solutal convection in a vertical orientation is found to be more suppressed than a tenth reduction of gravitational accelerations in a horizontal orientation. For crystal growth parameters under consideration, the greater uniformity in the growth rate is obtained for either solutal convection mode in a vertical orientation or thermal convection mode in horizontal geometry. The growth rate is also found to be first order exponentially decayed for $10{\leq}P_B{\leq}200$ Torr.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.4
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• pp.172-183
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• 2009

For the effects of the nonlinear temperature profiles and reduced-gravity conditions we conduct a two-dimensional numerical modeling and simulations on the physical vapor transport processes of $Hg_2Cl_2-Xe$ system in the horizontal orientation position. Our results reveal that: (1) A decrease in aspect ratio from 5 to 2 leads to an increasingly nonuniform interfacial distribution and enhances the growth rate by one-order magnitude for normal gravity and linear wall temperature conditions. (2) Increasing the molecular weight of component B, Xenon results in a reduction in the effect of solutal convection. (3) The effect of aspect ratio affects the interfacial growth rates significantly under normal gravity condition rather than under reduced gravitational environments. (4) The transition from the convection-dominated regime to the diffusion-dominated regime ranges arises near at 0.1g$_0$ for operation conditions under consideration in this study.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.465-474
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• 1999

RNase activity of Saccharomyces cerevisiae ATCC 7754 was investigated to obtain strains with high ribonucleic acid (RNA) content. The yeast strain contained two RNase activities; an acidic RNase with a optima of pH $3{\sim}4$ and an alkaline RNase with a optima pH 9. The acidic RNase activity was inhibited by $0.08\;M\;HgCl_{2}$ most drastically. The alkaline RNase activity was inhibited by 2.0 M NaCl or KCl, while enhanced by addition of $0.05\;M\;CaCl_{2},\;0.02\;M\;ZnSO_{4},\;or\;0.008\;M\;HgCl_{2}$. Various mutants of Saccharomyces cerevisiae ATCC 7754 were isolated by ethylmethane sulfonate (EMS) treatment or $\gamma$-ray/ultra violet irradiation. Among the mutants that were sensitive to high concentration of KCl which inhibits alkaline RNase, B24 was selected for high RNA content per culture volume. Growth characteristics of the mutant were comparable to those of the mother strain with optimum growth at pH $4.5{\sim}5.5$. The mutant accumulated higher content of RNA than the mother strain when glucose was used as the carbon source. However, both growth rate and total RNA content of the mutant were higher in molasses medium than in glucose medium. RNA content of the mutant increased rapidly during the early stage of growth, and then decreased gradually until the culture reached stationary phase by a fed-batch culture in a 5 L jar fermenter. Maximal cell harvest and the final RNA content using the mutant B24 were 69.6 g/L culture broth and 19.8 g/100 g of the dry cell while those using the mother strain were 68 g/L culture broth and 16.1 g/100 g of dry cell, respectively.

• Journal of Acupuncture Research
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• v.18 no.2
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• pp.101-110
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• 2001

Objective : This study was undertaken to determine if Scutellaria baicalensis Georgi (SbG) extract exerts protective effect against oxidant-induced cell injury in renal proximal tubular cells. Methods : The cell injury was evaluated by lactate dehydrogenase (LDH) release in rabbit renal cortical slices and lipid peroxidation was estimated by measuring malondialdehyde (MDA). t-Butylhydroperoxide (tBHP) was used as a model of oxidant. Results : tBHP at 1 mM increased LDH release and lipid peroxidation, which were prevented by SbG in a dose dependent manner over concentration range of 0.001-0.1%. SbG provided the protective effect against oxidant-induced reduction in PAH uptake by renal cortical slices and microsomal Na+-K+-ATPase activity. SbG attenuated tBHP-induced depletion of reduced glutathione. 0.2 mM $HgCl_2$ increased LDH release and lipid peroxidation, which were completely prevented by 0.05% SbG. Conclusion : SbG prevents oxidant-induced impairment in membrane transport function.

• Journal of Acupuncture Research
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• v.19 no.5
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• pp.209-218
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• 2002

Objective : This study was undertaken to examine whether Carthami Semen aquacupuncture (CSA) exerts protective effect against Hg-induced cell injury in rabbit liver. Methods : The cell injury was evaluated by ALT activity and lipid peroxidation was estimated by measuring malondialdehyde (MDA). Results : Hg caused an increase of ALT activity and lipid peroxidation in a dose-dependent-manner over concentrations of 0.1-1 mM, which were prevented by addition of 0.005% CSA. The protective effect of CSA was dose-dependent in concentration range of 0.001 to 0.01%. The increase of ALT activity and lipid peroxidation induced by 0.5 mM Hg were almost completely decreased by addition of 0.01% CSA. When the liver tissues were exposed to 0.5 mM Hg, GSH content was decreased, which was significantly restored by 0.01% CSA. 0.5 mM Hg caused decrease in the amount of total and nonprotein sulfhydryl groups, and 0.01% CSA prevented Hg-induced reduction of nonprotein sulfhydryl group but not protein sulfhydryl group. Conclusions : These results suggest that CSA exerts protective effect against Hg-induced cell injury by antioxidant action resulting from enhancement of nonprotein sulfhydryl group content including GSH in liver.