• Biomolecules & Therapeutics
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• v.3 no.2
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• pp.165-170
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• 1995

The biochemical properties of the fibrinolytic protease of 50,800 Da isolated from the venom of Kgdistrodon blomhoffi brevicaudus were characterized. The enzyme hydrolyzed the carboxyl side of arginine in the synthetic chromogenic peptides, N-Benzoyl-Phe-Val-Arg-pNA and N-p-Tosyl-Gly-Pro-Arg-pNA, and the enzyme activity was inhibited by phenylmethylsulfonylfluoride indicating that the enzyme belongs to the serine protease family. The pretense showed maximum activity at pH 7.5 and inhibited by ZnCl$_2$, CuSO$_4$, but not by soybean trypsin inhibitor, pepstatin A, 2-mercaptoethanol and EDTA. The fm value determined with N-p-Tosyl-Gly-Pro-Arg-pNA was 0.2 mM. The thrombolytic activity of the purified enzyme was evaluated by platelet aggregation test in rabbits. While the platelet count ratio in blood of the rabbits injected with thrombin alone declined from 1.0 to 0.6 within 7 min and maintained around 0.6 for 24 hours thereafter, the ratio rapidly recovered from around 0.6 to 0.8 in 1 hr, to 1.0 in 24 hrs when the rabbits were sequentially treated with thrombin and the purified enzyme. The result showed that the serine protease from A. blomhoffi brevicoudus of 50,800 Da had a thrombolytic activity in vivo and the enzyme might be developed as a therapuetic agent for the treatment of thrombic disease.

• Journal of Ocean Engineering and Technology
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• v.19 no.5 s.66
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• pp.43-49
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• 2005

This paper is to investigate the effect of corrosion by acoustic emission method in tensile loading and the adhesiveness between substrate and coating layer. The powders used are Zn and Amdry625, respectively. They are coated on brass alloy substrate. AE signals of Zn and Amdry625 coating layer increase drastically in strain $2\%$. However, those of Zn specimen have more than those of Amdry625 specimen. When the specimens executed the corrosion test under $3.5\%$ NaCl solution for 500, 1000 hours, the salt solution penetrated into the surface of the substrate through the pores of the coating layer. As a result, corrosion production formed on the surface of the substrate. The adhesiveness between coating layers is weakened by the polarization and corrosion itself. The AE event, count, and energy of corroded coating specimens decrease, compared to specimens without corrosion. The results are summarized as follows : 1. In the tensile tests, the time that it took to start and develop the cracks and exfoliations between the surface of the substrates and the plasma spray coatings were different according to the type of plasma sprayed material, which are Zn and Amdry625. These phenomena were obvious at the strain rate 1 to $5\%$, and few available data were found after that stage. 2. The specimens with Zn coating showed the characteristics of crack, according to the changes of the tensile strength applied on the substrates while those with Amdry625 showed exfoliation as a result of low adaptation to the tensile strength. 3. The anti-corrosion specimens showed that the adhesive properties between the substrate and the plasma spray coating were strong in the order of Zn, Amdry. It showed that Corroded specimens cracked or exfoliated easily, even with the small energy, because those had a comparatively weakened adhesive property, due to corrosion. 4. Zn specimen showed no corrosion phenomena on the surface of the substrates, because they had the function of sacrifice anode however, Amdry625 specimen showed the corrosion, because it did not have that function.

• Analytical Science and Technology
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• v.15 no.4
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• pp.365-372
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• 2002

In this study, inorganic elemental distribution in Korean adult human tissue of liver, lung, muscle, kidney, rib and thyroid has been investigated. These tissues were collected from human's body within 48 hours after their death according to IAEA's recommended method, dried by freeze drying method and then pulverized. Neutron activation analysis was applied to these samples to determine the concentrations of 5 major elements of Ca, Mg, Na, K, and Cl and 12 trace elements of Mn, I, Sr, As, Br, Co, Cr, Cs, Fe, Rb, Se, and Zn. To confirm accuracy of analytical result was performed using three kinds of standard reference materials and resulted that the relative error is within 10% for the most of elements and the Z-score indicating a performance of analysis is within 2. The elemental distribution shows that the major elements are distributed homogeneously with a specific concentration and that the trace elements shows a distribution of different concentration with kinds of tissue and their age. Particularly, iodine shows higher concentration with 1000 ${\mu}g/g$ in thyroid, and calcium and strontium show the concentration with 15.9% and 84.4 ${\mu}g/g$ in rib, respectively.

• Economic and Environmental Geology
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• v.32 no.5
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• pp.421-434
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• 1999

Gas and chemical compositions of fluid inclusions in quartz some of Au-Ag, Pb-Zn-Cu and W-Mo mineral deposits in South Kores were analyzed to interpret the sources of ore fluid and the depositional condition of ore minerals in base-metal ore deposits. Fluid inclusions in quartz from the gold and silver mines are characterized by $CO_2$ rich fluids which have a wide range in $CH_4 \;and\; CO_2$ contents ($CH_4/CO_2$=0.001-0.225). The $CO_2$ rich but $CH_4$-poor nature of the fluid reflects the high fo2 condition during the mineral precipitation. The C2H6 is detected in hydrothermal quartz vines in metasedimentary rocks from the Jeonjoo-il, Youngbokari and Taechang mines. The $CH_4 /CO_2$ rations in W-Mo bearing quartz veins range from 0.005 to 0.214, which is similar with those in Au-Ag mines. However, skarn formation stage. Fluid inclusions, A relatively good correlation between Na and Cl contentrations reflects varible salinity in the fluid inclusion, it is suggested that the chemistry of promary magmatic hydrothermal fluids has changed during post-magmatic alteration and/or wall rock alteration processes. The content of gas compositions also depends on the kinds of country rocks, supporting above conclusion.

• Food Science and Preservation
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• v.8 no.4
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• pp.419-426
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• 2001

This study was carried out to develope a convenient instant spiced Toha-jeot. Toha-jeot was manufactured by five samples; 8%, 10%, 13% 23% sodium chloride and a conventional type soy sauce. The Toha-jeot was refrigerated at 4$\pm$1$\^{C}$ for 3 months and then boiled glutinous rice, red pepper powder, chopped garlic and ginger were added, and the spiced Toha-jeot was fermented at 4$\pm$1$\^{C}$ for 2 months, was freeze-dried at a condition of 40$\^{C}$, vacuum 100∼200 millitor millitorr and then packed in vacuum. It is called freeze-dried instant spiced Toha-jeot (FIST). Changes in the components and quality of refrigerated spiced Toha-jeot (RST) and FIST were investigated for 30day. The moisture content of RST was 53.79∼58.91%. Among the mineral constituents of RST, Na and Ca were dominantly occupying. Water activity of FIST was 0.28-0.39 while that of RST was 0.87-0.92. TBA value of FIST was lower than that of RST. Acidity, VBN (volatile basic nitrogen) and TBA(thiobarbituric acid) of the FIST and RST increased slightly, whereas pH decreased. The major components of fatty acids in FIST and RST were analysed into a feater amount of linoleic acid (Cl8:2), palmitic acid (Cl6:1), oleic acid (Cl8:1), linolenic acid (Cl8:3), EPA (C2O:5) and stearic acid(Cl8:0). In sensory evaluation, the RST had higher scores in color and taste and the FIST in chewiness and flavor. The qualitative characteristics and sensory evaluation of FIST and RST were similar.

• Journal of Environmental Science International
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• v.16 no.12
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• pp.1337-1343
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• 2007

The aim of this study was to isolate chicken feather-degrading bacteria with high keratinolytic activity and to investigate cultural conditions affecting keratinolytic enzyme production by a selected isolate. A chicken feather-degrading bacterial strain CH3 was isolated from poultry wastes. Isolate CH3 degraded whole chicken feather completely within 3 days. On the basis of phenotypical and 16S rDNA studies, isolate CH3 was identified as Bacillus thuringiensis CH3. This strain is the first B. thuringiensis described as a feather degrader. The bacterium grew with an optimum at pH 8.0 and $37^{\circ}C$, where maximum keratinolytic activity was also observed. The composition of optimal medium for keratinolytic enzyme production was feather 0.1%, sucrose 0.7%, casein 0.3%, $K_2HPO_4$ 0.03%, $KH_2PO_4$ 0.04%, $MgCl_2$ 0.01% and NaCl 0.05%, respectively. The keratinolytic enzyme had a pH and temperature optima 9.0 and $45^{\circ}C$, respectively. The keratinolytic activity was inhibited ethylenediaminetetraacetic acid, phenylmethylsulfonyl fluoride, and metal ions like $Hg^{2+},\;Cu^{2+}\;and\;Zn^{2+}$. The enzyme activated by $Fe^{2+}$, dithiothreitol and 2-mercaptoethanol.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.5
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• pp.479-482
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• 1991

The medical use of Acer mono MAX. and Betula costata T. sap has had the long history in Korea. So the mineral and sugar contents of these sap gathered in Mt. Jiri area at spring were analyzed to investigate the scientific base of folk remedies by using ion liquid chromatography and high performance liquid chromatography. The values of chlorine and sulfate in Acer mono MAX. were 11.5 mg/l and 176.7 mg/l, and in Betula costata T. 26.5 mg/l and 162.4 mg/l, respectively. The values of potassium, sodium, calcium and magnesium in Acer mono MAX. were 67.9 mg/l, 5.6 mg/l, 73.8 mg/l and 4.5 mg/l, and in Betula costata T. were 152.1 mg/l, 9.7 mg/l, 39.2 mg/l and 5.7 mg/l, respectively. The values of copper, zinc and manganese in Acer mono MAX. were 0.057 mg/l, 0.483 mg/l and 5.071 mg/l, and copper, zinc, mangances and iron in Betula costata T. were 0.038 mg/l, 1.584 mg/l, 4.354 mg/l and 2.511 mg/l, respectively. The values of sucrose in Acer mono MAX. were 27.29 mg/l, glucose and fructose in Betula costata T. were 0.97 g/l and 3.05 g/l, respectively.

• Journal of Environmental Science International
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• v.12 no.6
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• pp.665-676
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• 2003

To investigate the chemical characteristics of PM$\_$2.5/ in Seoul, Korea, atmospheric particulate matters were collected using a PM$\_$10/ dichotomous sampler including PM$\_$10/ and PM$\_$2.5/ inlet during the period of October 2000 to September 2001. The Inductively Coupled Plasma-Mass Spectromety (ICP-MS), ion Chromatography (IC) methods were used to determine the concentration of both metal and ionic species. A statistical analysis was performed for the heavy metals data set using a principal component analysis (PCA) to derived important factors inherent in the interactions among the variables. The mean concentrations of ambient PM$\_$2.5/ and PM/sub10/ were 24.47 and 45.27 $\mu\textrm{g}$/㎥, respectively. PM$\_$2.5/ masses also showed temporal variations both yearly and seasonally. The ratios of PM$\_$2.5/PM$\_$10/ was 0.54, which similar to the value of 0.60 in North America. Soil-related chemical components (such as Al, Ca, Fe, Si, and Mn) were abundant in PM$\_$10/, while anthropogenic components (such as As, Cd, Cr, V, Zn and Pb) were abundant in PM2s. Total water soluble ions constituted 30∼50 % of PM$\_$2.5/ mass, and sulfate, nitrate and ammonium were main components in water soluble ions. Reactive farms of NH$_4$$\^$+/were considered as NH$_4$NO$_3$ and (NH$_4$)$_2$SO$_4$ during the sampling periods. In the results of PCA for PM$\_$2.5/, we identified three principal components. Major contribution to PM$\_$2.5/ seemed to be soil, oil combustion, unidentified source. Further study, the detailed interpretation of these data will need efforts in order to identify emission sources.

• Microbiology and Biotechnology Letters
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• v.23 no.4
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• pp.432-438
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• 1995

The intracellular alginase from Vibrio sp. AL-145 was purified by ion chromatography on DEAE-Cellulose column, Q-Sepharose column, and gel filtration on Sephadex G-100 column. The optimum pH and temperature for the activity of the purified intracellular enzyme were 8.0 and 37$\circ$C, respectively. The enzyme was stable at the pH range of 7.5-8.5, and at 30$\circ$C for 30 min. The molecular weight of the intracellular enzyme was estimated to be about 23, 000 daltons by SDS-polyacrylamide gel electrophoresis. NaCl was required for enzyme activity and the optimum concentration was 0.5 M. The activity of intracellular enzyme was inhibited by Co$^{2+}$, Hg$^{2+}$, Zn$^{2+}$, 0-phenanthroline, $\rho$-CMB, EDTA and iodoacetate, and stimulated by Ca$^{2+}$, L-cysteine and 2-mercaptoethanol. This enzyme was an alginase specifically degrading alginic acid.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.61-64
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• 2003

This study was conducted to investigate the chemical characteristics of $PM^{10}$ at Anmyeon-do during the periods from January 1998 to December 2001. The $PM^{10}$ samples ($PM^{10}$) were collected by High Volume Air sampler (HVAS). The measured items were mass concentration of $PM^{10}$ with the major ions ($Cl^{-}$, ${SO_{4}}^{2-}$, ${NO_3}^{-}$, ${Mg}^{2+}$, ${Ca}^{2+}$, ${K}^{+}$etc.) and metallic elements (AI, Fe, Mn, Cr, Zn, Pb etc.). The chemical analysis of major ion components were made by Ion Chromatography (DX-500) and that of metallic elements were made by Inductively Coupled Plasma Spectrometer (ICP-AES, ICP-Mass). The average mass concentration of $PM^{10}$ increased substantially during the heavy dust periods (Asian Dust cases). For water-soluble ions, concentrations of ${Ca}^{2+}$, ${SO_{4}}^{2-}$ and ${NO_3}^{-}$ were remarkably enhanced. Concentrations and mass fraction of crustal elements such as Na, Mg, Ca, Fe, Mn were highly elevated, but those of pollution-derived heavy metals were appreciably decreased. The factor analysis was conducted in order to make the large and diverse data set as manageable levels and to qualitatively examine the relationship between the variables.