• Journal of Food Hygiene and Safety
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• v.27 no.1
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• pp.37-41
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• 2012

The current standard for testing tetrodotoxin (TTX) in foodstuffs is the mouse bioassay (MBA) in Korea as in many other countries. However, this test suffers from potential ethical concerns over the use of live animals. In addition, the mouse bioassay does not test for a specific toxin thus a sample resulting in mouse incapacitation would need further confirmatory testing to determine the exact source toxin (e.g., TTX, STX, brevotoxin, etc.). Furthermore, though the time of death is proportional to toxicity in this assay, the dynamic range for this proportional relationship is small thus many samples must be diluted and new mice be injected to yield a result that falls within the quantitative dynamic range. Therefore, in recent years, there have been many efforts in this field to develop alternative assays. High performance liquid chromatography (HPLC) coupled with mass spectrometry (MS) has been emerged as one of the most promising options. A LC-MS-MS method involves solid-phase extraction (SPE) and followed by analysis using an electrospray in the positive ionization mode and multiple reactions monitoring (MRM). To adopt LC-MS-MS method as alternative standard for testing TTX, we performed a validation study for the quantification of TTX in puffer fish. This LC-MS-MS method showed good sensitivity as limits of detection (LOD) of $0.03{\sim}0.08{\mu}g/g$ and limits of quantification (LOQ) of $0.10{\sim}0.25{\mu}g/g$. The linearity ($r^2$) of tetrodotoxin were 0.9986~0.9997, the recovery were 80.9~103.0% and the relative standard deviations (RSD) were 4.3~13.0%. The correlation coefficient between the mouse bioassay and LC/MS/MS method was higher than 0.95.

• Journal of Korea Foresty Energy
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• v.19 no.2
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• pp.93-101
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• 2000

Wood of Robinia pseudoacacia and bark of Populus alba$\times$P. glandulosa, Fraxinus rhynchophylla and Ulmus davidiana var. japonica were collected and extracted with acetone-water(7:3, v/v) in glass jar to examine whether its bioactive compounds exist. The concentrated extracts were fractionated with hexane, chloroform, ethylacetate and water, and then freeze-dried for column chromatography and bioactive tests. The isolated compounds were sakuranetin-5-O-$\beta$-D-glucopyranoside from Populus alba $\times$Pl glandulosa, 4--ethyoxy-(+)-leucorobinetinidin frm R. pseudoacacia and fraxetion from F. rhynchophylla and were characterized by $^1H$ and$^{13}C $ NMR and positive FAB-MS. Decay-resistant activity was expressed by weight loss ratio and hyphae growth inhibition in the wood dust agar medium inoculated wood rot fungi. R. pseudoacacia showed best anti-decaying property in both test and its methanol untreated samples, indicating higher activity than methanol treated samples in hyphae grwoth test. In antioxidative test, $\alpha$-tocopherol, one of natural antioxidants, and BHT, one of synthetic antioxidants, were used as references to cmpare with the antioxidant activities of the extacted fractions. Ethylacetate fraction of F. rhynchophylla bark indicated the hightest activity in this test and all fractions of R. pseudiacacia extractives also indicated higher activities compared with the other fractions. In the isolated compounds, aesculetin isolated from F. rhynchophylla bark showed best activity and followed by robonetinidin from R. pseudoacaica.

• Journal of the Korean Chemical Society
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• v.63 no.6
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• pp.420-426
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• 2019

Selenoproteins,in Korean blood serum, GPx, SelP, and SeAlb were separated and determined with the use of HPLC-ICP/MS. Deuterium was used as a collision gas and affinity column with ammonium formate was used as an eluting solvent for the accurate quantitation of selenoproteins in human blood serum. Certified reference material BCR 639 (133±12 ng g^-1) was tested for the accuracy and the result was satisfactory 130±6 ng g^-1. Blood serum for the rectal cancer and controlled groups were collected and analyzed to give 84±27 ng g^-1, and 119±28 ng g^-1, respectively. The difference was statistically obvious when t-test was performed (t_cal 4.93 > t_95% 2.04). The decrease for cancer group was more obvious for female and aged group. The distributions of three selenoproteins were similar with each other, which means rectal cancer group did not show any specificity for any selenoproteins. As cancer developed, GPx showed a slight decrease but not obvious while the total concentration was increasing particularly at the second stage of cancer.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.1
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• pp.49-56
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• 2005

Many different kinds of radwastes are discharged from the nuclear power plants, and $^{129}$I is included in these radwastes. Recovery test of $^{129}$I was evaluated for different radwastes(dry active waste, sludge, spent resin and simulated evaporator bottom). Recovery of $^{129}$I for dry active waste by acid leaching with $1.8\%$ NaClO was $74.3\%$$(RSD,\;2.2\%)$ and l291 for spent rein by alkali fusion method with KOH as a flux agent was $87.7\%$$(RSD,\;0.9\%$), respectively. iodide in simulated evaporator bottom containing a high concentration of borate was adsorbed with anion exchange resin at pH 7 phosphate buffer solution. Recovery of $^{129}$I for anion exchange resin was $92.5\%$ and not affected up to 1,200 $\mu$g/mL $H_3BO)3$(as a Boron). Recovery of $^{129}$I for the spent resin from nuclear power plant was $87.2\%$ $(RSD,\;1.2\%)$.

• Journal of Mushroom
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• v.12 no.4
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• pp.275-279
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• 2014

Pleurotus pulmonarius usually grows on the dead wood of deciduous trees from mid summer to early fall. Cultivation of this mushroom is recently increasing due to its good flavour and fragrance. This study was conducted to find out the favorable substrate formulation in the bottle and bag cultivation of P. pulmonarius. The V formulation (10 : 50 : 20 : 20 mixing ratio of poplar sawdust, cottonseed hull, cottonseed meal and beet pulp) showed the fastest mycelial growth in the test tube column medium and highest yields in both bottle cultivation and bag cultivation. Those chemical conditions were pH 5.52, 29.07% organic matter contents, 1.12% total nitrogen, 25.95 OM/N ratio, 0.16% CaO, 0.51% $K_2O$, 0.17 MgO and 0.26 $P_2O_5$.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.2
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• pp.178-182
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• 2006

The purpose of this research is to remove the bromate that is a disinfection by-poduct of water purification by ozone. I achieved a high rate of removal with iron, copper, or silver impregnated activated carbon by using both the adsorbing power of granular activated carbon and the oxidizing power of metal ions as deoxidizing agents. In the removal test of bromate with the quantity of activated carbon input I injected each activated carbon by 0.1, 0.3, 0.1, and 1.0 g and let them react for 240 minutes. I found the quantity of removed bromate was in proportion to the amount of input. The removal rate of bromate increased about 20% when I used acid treated activated carbon. The metal impregnated activated carbon had a higher removal rate of bromate than that of general activated carbon by about $30{\sim}50%$. Iron impregnated activated carbon showed a 92% removal rate of bromate. Iron, copper, or silver impregnated activated carbon removed about $0.9{\sim}1.5mg\;{BrO_3}^-/g$ while general activated carbon removed about $0.02{\sim}0.45mg\;{BrO_3}^-/g$. In the continuous column reaction, there were breakthrough phenomena at 96, 180, and 252 hours when I tested EBCT by 1, 2 and 3 minutes while I was changing the flux rate of bromate from 15.6 to 46.8 mL/min.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.684-688
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• 1996

In order to search for antithrombotic peptides from soybean paste, the inhibitory activity of water extract of soybean paste and its peptide fractions on ADP-induced aggregation of washed platelets was assayed. Soybean paste extract treated with ultrafiltration (M.W. cut off, 3,000 daltons) was found to have inhibitory activity of 90% at the dose of $96\;{\mu}g/ml$ by the method of turbidometric aggregometer. Soybean paste extract was fractionated to 19 fractions (No. B-18) by Dowex 50W X-2 ion exchange column chromatography and activity test was performed by the microplate method. All of the fractions had antithrombotic activity $(IC_{50},\;101,000\;{\mu}g/ml)$, and most fractions had higher activity than positive control, RGDS $(IC_{50}.\;205\;{\mu}g/ml)$. Especially, basic fractions No.16-18 showed higher activity than soybean paste extract $(IC_{50},\;30\;{\mu}g/ml)$. The fraction No.16 with the highest activity $(IC_{50},\;10\;{\mu}g/ml)$ was purified and analysed for amino acid composition. The results showed that histidine, arginine, and alanine were major residues in the peptide part of the fraction.

• The Journal of Engineering Geology
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• v.15 no.1
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• pp.29-39
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• 2005

For detecting a ground contamination survey, soil sampling method have been used a drilling or coring technique in general. However these methods are very difficult to systematically real-time monitoring of variation of contamination degree in field. ]'n this research frequency Domain Reflectometry (FDR) system was suggested and carried out to experimental approaches for determination of oil contamination on surface and underground. Experimental method using FDR method was discussed with feasibility of measurement in the laboratory column test. It is determined to degree of oil contamination due to response of dielectric constant re-lated with volumetric water content(θ/sub w/) and volumetric oil content( θ/sub al/ ) of saturated and unsaturated soil media. And physical properties such as effective porosity and oil residual ratio of saturated soil media were also measured through real-time monitoring works using installed FDR measurement sensors, which are defected characteristics of oil movement in the saturated soil media under the soil column tests. In the results of these experiments, a range of effective porosity was estimated to about 0.35 compared with initial porosity 0.40 of manufactured saturated soil media, which is also calculated to about 87.5% to the ratio of initial porosity to effective porosity. Finally oil residual ratio which is compared with volumetric water content and volumetric oil content was calculated about 62.5%.

• Journal of the Korean Society of Marine Environment & Safety
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• v.10 no.1 s.20
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• pp.69-73
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• 2004

Control if Sediment is very important in prawn farm due to the eruption of toxic materials such as unionized $H_{2}S,\;NH_{3}\;and\;NO_3$. In this study, column test was conducted with filter media such as activated carbon, zeolite, oyster shell and iron chloride to evaluate the reduction of toxicity from sediment. ammonia-N($NH_3$) was effectively removed by Zeolite and oyster shell. It was indicated that ammonium ion($NH_4^+$) was removed by ion exchange of zeolite. And the ammonia in the column of oyster shell was existed as the form of $NH_4^+$, which is not toxic for prawn because oyster shell was stably kept at $8{\sim}9g$ of pH. Therefore, some of ammonia($NH_4^+$) was removed by oyster shell. Hydrogen sulfide and COD were effectively removed by adsorption of activated carbon and a partial removal of hydrogen sulfide was accomplished by Oyster shell. Phosphorous was removed by activated carbon, oyster shell and iron chloride. In prawn farm, the concentration of ammonia was increased with increase of pH by algae photosynthesis in the column of activated carbon, zeolite and iron chloride, but it was revealed that pH was stably kept in the column of oyster shell.

• KSBB Journal
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• v.22 no.2
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• pp.102-108
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• 2007

A sewage was treated using a vertical flow zeolite-filled reed bed. The sewage from the student dormitory of Changwon National University was fed into the reed bed for 10 minutes every 6 hours at the hydraulic load of $314L/m^3{\cdot}$day. The filtering height of the reed bed was 100 em and the zeolite mixture was filled in the reed bed. The mixture consisted of the same volume of two types of zeolite: 0.5$\sim$1 mm and 1$\sim$3 mm in diameter. Annual average removal efficiency was 88 89.9%, $COD_{Cr}$ 86.1 %, $COD_{Mn}$ 81.2%, T-N 34.0%, $NH_4^+$-N 97.3% and T-P 34.6%. T-N of effluent was mostly $NO_3^-$-N and the concentration of $NO_2^-$-N in effluent was lower than 0.1 mg/L. All removal efficiencies did not show a remarkable seasonal change. The ranking of phosphorous fractions fixed to the zeolite in column test was Ca-P > Fe-P > reductant soluble Fe-P > occluded P > saloid P > AI-P at all depths of the filter. All phosphorous fractions except for AI-P reduced at deeper filter layer, while their content ratios increased at deeper filter layer. Organic matter content was the highest at the highest layer (0$\sim$5 cm from the top of the filter) and only small differences were observed at the deeper filter layer than 5 em from the top. Organic matter content increased at all depths of the filter with the operating time.