• Journal of Life Science
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• v.29 no.11
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• pp.1294-1303
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• 2019

Perchlorate is an anionic pollutant that is very soluble and stable in water. It has been detected not only in soil/ground water but also in surface water, drinking water, food, fish, and crops. Perchlorate inhibits iodine uptake by the thyroid gland and reduces production of thyroid hormones that are primarily responsible for regulation of metabolism. Although various technologies have been developed to remove perchlorate from the environment, biodegradation is the method of choice since it is economical and environmentally friendly. However there is limited information on perchlorate biodegradation in salt environment such as salt water. Therefore this paper reviews biodegradation of perchlorate in salt water and related microorganisms. Most biodegradation research has employed heterotrophic perchlorate removal using organic compounds such as acetate as electron donors. Biodegradation research has focused on perchlorate removal from spent brine generated by ion exchange technology that is primarily employed to clean up perchlorate-contaminated ground water. Continuous removal of perchlorate at up to 10% NaCl was shown when bioreactors were inoculated with enriched salt-tolerant perchlorate-reducing bacteria. However the reactors did not show long-term stable removal of perchlorate. Microorganisms belonging to ${\beta}$- and ${\gamma}$-Proteobacteria were dominant in bioreactors used to remove perchlorate from salt water. This review will help our understanding of perchlorate removal from salt water to develop a decent biotechnology for the process.

• The Journal of the Petrological Society of Korea
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• v.23 no.3
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• pp.197-208
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• 2014

Zircon separated from a biotite schist of the Guryong Group in Odesan area, eastern part of the Gyeonggi Massif in Korea were analysed for SHRIMP U-Pb ages. CL images display composite core-rim structures of the zircon, indicating an in-situ overgrowth of zircon through a high-grade metamorphism. The metamorphic zircon rims give a weighted mean age of $247{\pm}6Ma$. While the detrital zircon cores have zoning patterns and Th/U ratios indicative of a magmatic origin. Among 53 analyses from the cores, 46 data yield near concordant ages which are concentrated at $378{\pm}10Ma$ (n=9), $420{\pm}4Ma$ (n=6) and $1845{\pm}9Ma$ (n=18) with sporadic Neoproterozoic ($687{\pm}9Ma$) to late Archean ($2519{\pm}20Ma$) ages. The age data constraint sedimentation age of protolith of the Guryong Group, so far unknown, as late Paleozoic. The Guryong Group of this study is the first late Paleozoic strata reported from eastern Gyeonggi Massif, and its maximum depositional age (ca 378 Ma) is identical with those of the late Paleozoic strata in the southwestern Ogcheon Belt. The Triassic metamorphic age and abundant middle Paleozoic provenance (361~425 Ma) of the Guryong Group are similar with those reported from the Triassic collisional belt in central China. Thus this study indicates that the Odesan area would be an possible eastward extension of the Triassic collisional belt in central China.

• Journal of Life Science
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• v.32 no.10
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• pp.749-761
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• 2022

This study evaluated the antioxidizing and antiproliferative effects of Angelica japonica extract and its solvent-partitioned fractions. A dried sample of the halophyte A. japonica was extracted twice using methylene chloride (CH₂Cl₂) and extracted twice again using methanol (MeOH). The combined crude extracts were then fractionated by solvent polarity into distilled water (water), n-butanol (n-BuOH), 85% aqueous methanol (85% aq.MeOH), and n-hexane fractions. The antioxidant activities of the crude extracts and their solvent-partitioned fractions were assessed according to their DPPH radical and peroxynitrite scavenging abilities, formation of intracellular reactive oxygen species (ROS), DNA oxidation, NO production, and ferric reducing antioxidant power (FRAP). The crude extract showed significant antioxidant activity in the overall antioxidizing bioassay systems. Among solvent-partitioned fractions, good antioxidant activities were observed in n-BuOH and 85% aq.MeOH fractions and significantly correlated with the polyphenol and flavonoid contents of the samples. Furthermore, all samples tested, including the crude extract, not only showed cytotoxic effects against human cancer cells (AGS, HT-29, MCF-7, and HT-1080) but also prevented cell migration in a dose-dependent manner in the wound healing assay using HT 1080. Among the solvent-partitioned fractions, the 85% aq.MeOH fraction most effectively inhibited the invasion of HT-1080 cells. Therefore, these results suggest that A. japonica may be a potential antioxidizing and antiproliferative agent.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.3
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• pp.198-204
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• 2000

In order to utilize by-products which would normally be discarded in marine processing plants, cod teiset protein was hydrolyzed and antioxidative actiTity of the hydrolysate was investigated. AntioxidatiTe peptide was isolated using ultrafiltration membrane, ion-exchange chromatography on a SP-Sephadex C-25 column, gel filtration on a Sephadex G-15 column, high performance liquid chromatography on an ODS column, and capillary electrophoresis chromatography. Antioxidative activities of the cod teiset hydrolysate were compared with ${\alpha}-tocopherol$, one of the commercial antioxidant. The hydrolysate passed through a membrane with molecular weight cut-off (MWCO) 1 kDa was shown the strongest antioxidative activity, and the activity was higher $10{\%}$ as compared with ${\alpha}-tocopherol$. In addition, the peptide isolated by ion-exchange chromatography, gel filtration, and HPLC, respectively, was higher $53{\%}$ as compared with ${\alpha}-tocopherol$, and the amino acid sequence was Ser-Asn-Pro-Glu-Trp-Ser-Trp-Asn.

• Journal of Applied Biological Chemistry
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• v.54 no.3
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• pp.218-224
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• 2011

This study was conducted to estimate the water quality of agricultural groundwater well located in Buan-gun, Jinan-gun, Sunchang-gun, and Jangsu-gun of Jeollabuk-do. The groundwater samples were collected at 328 sites (Buan-gun: 158, Jansu-gun: 45, Sunchang-gun: 32, Jinan-gun: 93, respectively). We measured 4 kinds of general contaminants (pH, $NO_3-N$, $Cl^-$, and COD) and 10 kinds of specific contaminants (Cd, As, $CN^-$, Hg, phenol, Pb, $Cr^{+6}$, organophosphorus, trichloroethylene, and tetrachloroethylene). Generally, the level of general contaminants and specific contaminants in the agricultural groundwater was suitable for water quality standard in all sites for agricultural irrigation water. Exceptionally, chloride concentrations were exceeded water quality standard of agricultural groundwater at some sites in western coast area of Jeollabuk-do. Although water quality standards in agricultural groundwater have been suitable, the water contaminants of agricultural groundwater in western coast area were gradually increased than eastern mountain area.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.5
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• pp.44-49
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• 2016

Among the deteriorating agents, chloride ion is reported to be one of the most harmful ions due to its rapid diffusion and direct effect on steel corrosion. Cold joint which occurs in mass concrete placing is vulnerable to shear resistance and more severe deterioration. The paper presents an quantitative evaluation of chloride diffusion coefficient in OPC(Ordinary Portland Cement) and GGBFS(Ground Granulated Blast Furnace Slag) concrete containing cold joint. GGBFS concrete shows $6.6{\times}10^{-12}m^2/sec$ which is almost 30% level of OPC concrete results and the trend is repeated in the case of cold joint concrete. Compared with OPC concrete, GGBFS concrete is evaluated to have better resistance to chloride penetration, showing 0.30 times of chloride diffusion coefficient in concrete without cold joint 0.39 times with cold joint, respectively.

• The Journal of Korean Society for Radiation Therapy
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• v.20 no.2
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• pp.109-113
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• 2008

Purpose: To evaluate the detector dependency in the various collimator size for Stereotactic Radiosugery (SRS). Materials and Methods: This study was performed with 6 MV photon beam (Varian 21EX, Varian, US) and the measurement detectors are used by ion chamber CC01, CC13 (Wellhofer, Germany) and stereotactic diode detector (SFD, Wellhofer, Germany). SRS collimator size was used by ${\varphi}$5, 10, 20, 30 mm (Brain Lab, Germany). Percentage depth dose (PDD) was measured at SSD 100 cm and field size 10×10 cm from individual detectors. Ouput factor was measured by using same setup of PDD and with maximum dose depth. Data was normalized at field size $10{\times}10\;cm$. Beam profile was measured at SSD 100 cm in SRS collimator ${\varphi}$10, 30 mm and field $10{\times}10\;cm$ and a comparison of FWHM (full width half maximum), penumbra width (20~80%). Results: The CC13 detector was overestimated 16% than other detectors from the PDD in the 5 mm collimator. Output factors were underestimated CC01 28%, CC13 72% in the 5 mm collimator and CC01 9.6%, CC13 25% in the 10 mm collimator than the SFD. Maximum difference was 3% at the FWHM of the dose profile in the 10 mm collimator and difference of the 30 mm collimator was 0% at the FWHM. Penumbra width was increased CC01 122%, CC13 194% in the 10 mm collimator and CC01 68%, CC13 185% in the 30 mm collimator than the SFD. Conclusion: It is very important for accurate dosimetry to select a detector in small field. The SFD was considered with the most accurate dosimeter for small collimator dosimetry in this study.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.1-8
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• 1997

A complement system-activating (anti-complementary) polysaccharide was purified from the hot water extract of young stems of Cinnamomum cassia Blume. Crude polysaccharide fraction (CC-1) was prepared from the hot water extract of the young stems followed by methanol-reflux, precipitation with ethanol, dialysis, and lyophilization. The anti-complementary activity of CC-1 was decreased greatly by periodate oxidation, but was not changed by pronase digestion. These suggest that carbohydrate moiety may be related to the activation of complement system. According to its ionic strength CC-1 was fractionated first using cetavlon to give 4 fractions, CC-2, 3, 4 and 5. Among them CC-2 fraction was found to retain the highest activity and yield. CC-2 was separated to an unabsorbed neutral sugar portion (CC-2-I) and seven absorbed acidic sugar fractions $(CC-2-II{\rightarrow}CC-2-VIII)$ on DEAE-Toyopearl 650C (Cl-). CC-2-III showing higher anti-complementary activity and yield than those of other fractions, was further purified on the gel permeation of Sephadex G-100 and Sepharose CL-6B to CC-2-IIIa-3. CC-2-IIIa-3 was determined to have a homogeneity hy GPC (Sepharose CL-6B) and HPLC. Gel chromatography using standard dextrans gave a value of $2.4{\times}10^5$ for the molecular weight. The purified polysaccharide, CC-2-IIIa-3 consisted of arabinose, xylose, glucose, galactose, galacturonic acid and glucuronic acid in a molar ratio of 5.56 : 3.77 : 1.87 : 1.00 : 5.12 : 3.13 and contained no nitrogen.

• Biomedical Science Letters
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• v.6 no.3
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• pp.209-221
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• 2000

The purpose of this study was to investigate the practical availability of pretense production that can be used at home after isolating Serratia sp.2000-1 which produced extracellular pretense from clinical specimen. Basic production conditions and partial enzymatic characteristics of pretense produced by Serratia sp. 2000-1 was as follows: The kind and concentration of carbohydrate, nitrogen and metal salts for optimal enzyme production condition were each identified as the concentration of 1.5% glucose, 2.0% CSP, and 0.1% CaCl$_2$, and the optimal temperature, time and initial pH for culture were each 3$0^{\circ}C$, 72 hours, and pH 8.0. The final enzymatic yeild that was purified by 3 steps with ammonium sulfate precipitation (45~80%), DEAE-cellulose column chromatography, and Sephadex G-200 gel chromatography was 14.4%, and enzyme inactivity rate increased approximately 291314s. The optimal temperature and pH for purified pretense activity were 35$^{\circ}C$ and pH 7.0~8.0, and purified pretense activity was relatively stable by 4$0^{\circ}C$ at pH 6~10 for 30 min, however heating at 6$0^{\circ}C$ for 30 min, it liminated detectable pretense activity. The pretense activity was activated by $Mg^{2+}$, $Ba^{2+}$, $Ca^{2+}$, Mn$^{2+}$, but inactiviaed by Hg$^{2+}$, Ag$^{2+}$, Cu$^{2+}$, and the pretense activity was inhibited strongly by SDS among enzyme activity inhibitors. Further study is required to evaluate the practical availability of pretense production that can be used at home by isolating Serratia sp. from more clinical specimen and examining pretense more in details.

• 한국해양학회지
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• v.3 no.1
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• pp.26-38
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• 1968

Nutrients and principal ions contents in downstream water of the Han River, near Seoul, measured at somewhat three week intervals over a period of two years were shown its characteristic seasonal cycles. The annual ranges of nutrients were 0.5-7.7 $\mu\textrm{g}$ at/L of ammonia, 0.12-0.90 $\mu\textrm{g}$ at/L of nitrite, 2.9-35.9 $\mu\textrm{g}$ at/L of nitrate, 8.8-42.0 $\mu\textrm{g}$ at/L of tatal soluble nitrogen, 0.09-0.57 $\mu\textrm{g}$ at/L of phosphorus, and 3.0-15.3 mg/L of silicate, and these were lower in spring and fall closely correlate with phytoplankton blooms and higher in winter except ammonia and silicate contents. Annual variations of BOD and COD were 0.10-2.14 ml/L, 0.88-6.82 mg/L, respectively. The ionic concentrations of Cl, Ca and Mg were not high of which Cl 5.0-13.1 mg/L, Ca 3.7-9.1 mg/L and Mg 1.5-10.4 mg/L of annual ranges. Fe ranged 18.5-82.8 $\mu\textrm{g}$/L, Mn 15-58 $\mu\textrm{g}$/L, Cu 0.3-4.7 $\mu\textrm{g}$/L annually In general, the Han River water is low in nutrients, mineral contents, and may be said not yet polluted, excellent quantity and quality of river water.