• Analytical Science and Technology
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• v.11 no.4
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• pp.271-280
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• 1998

Rice flour reference materials were prepared from the unpolished rice grown in Korea and certified for elemental composition. The reference materials consist of two samples containing normal and high level. The reference material at elevated level was prepared by spiking to the normal rice flour six toxic elements of As, Cd, Cu, Cr, Hg, Pb with $1.0{\mu}g/g$ on a dry weight basis. Homogeneity of the prepared materials was evaluated through the determination of Ca, Cu, Fe, Mn, Zn by instrumental neutron activation analysis (INAA) and atomic absorption spectrometry (AAS). Small variance of elemental composition among interbottled samples assured homogeneity of the prepared materials. The materials were decomposed by high pressure digestion and microwave digestion method. INAA, AAS, inductively coupled plasma-atomic absorption spectrometry (ICP-AES), ICP-mass spectrometry (MS) and vapour generation techniques were employed to analyze the reference materials. From this independent analytical results, the certified or reference values are determined for As, Ca, Cd, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, P, Pb, Se, Zn.

• The Journal of Engineering Geology
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• v.28 no.3
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• pp.465-473
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• 2018

The application of singular value decomposition (SVD) filtering is examined for attenuation of the ground-roll in land seismic data. Prior to the SVD computation to seek singular values containing the highly correlatable reflection energy, processing steps such as automatic gain control, elevation and refraction statics, NMO correction, and residual statics are performed to enhance the horizontal correlationships and continuities of reflections. Optimal parameters of SVD filtering are effectively chosen with diagnostic display of inverse NMO (INMO) corrected CSP (common shot point) gather. On the field data with dispersion of ground-roll overwhelmed, continuities of reflection events are much improved by SVD filtering than f-k filtering by eliminating the ground-roll with preserving the low-frequency reflections. This is well explained in the average amplitude spectra of the f-k and SVD filtered data. The reflectors including horizontal layer of the reservoir are much clearer on the stack section, with laminated events by SVD filtering and subsequent processing steps of spiking deconvolution and time-variant spectral whitening.

• Korean Journal of Food Science and Technology
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• v.41 no.5
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• pp.522-527
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• 2009

The principal objective of this study was to assess the effects of various manufacturing conditions of soy sauce containing hydrolyzed vegetable protein (HVP) (HVP-soy sauce) on 3-monochloropropane-1,2-diol (3-MCPD) contents. Various HVP soy sauces were prepared under different conditions of alkaline treatment and retention process. Derivatives of heptafluorobutylimidazole (HFBI) 3-MCPD were determined via GC/MS below $0.010{\mu}g/g$, which was sensitive with a good recovery rate. The quantity of 3-MCPD decreased with the pH and temperature of alkaline treatment, and the time and temperature of the retention process increased. Alkaline treatment at pH 10.0-10.5 and a 72 hr retention process were shown to reduce effectively the 3-MCPD contents of HVP-soy sauces. This result indicates that the manufacturing process, particularly alkaline treatment, and retention process would be critical steps in managing 3-MCPD contents in HVP-soy sauce.

• Journal of Sericultural and Entomological Science
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• v.46 no.2
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• pp.58-64
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• 2004

The current study was performed to clarify the pupation disorder symptoms in silkworm which herbicide, molinate has been regarded as a causal origin. Molinate residues in mulberry leaves was monitored in major rearing area of silkworm; Yeacheon, Sangju and Namwon. Detected range of the molinate in mulberry leaves was 0.002 to 0.013 mg/kg and detection frequency was 30.0 to 81.8%. Molinate concentration in the air of mulberry tree growing area was $0.004\;{\mu}g/m^3$. Water diluted solution of molinate at the concentration of 1, 10, 100 mg/l gave no abnormal symptoms in silkworm irrespective of spraying to silkworm or spiking to diet. Exposing the silkworm to the air containing 250, 2,500, and $10,000\;{\mu}g/m^3$ also revealed no abnormal symptom. These results illustrated that the abnormal growth of silkworm encountered in the field was not caused by pesticide contamination.

• Tuberculosis and Respiratory Diseases
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• v.70 no.3
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• pp.251-256
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• 2011

The prevalence of multi-drug resistant tuberculosis (MDR-TB), which is resistant to isoniazid and rifampin, has been increasing in Korea. And the side effects of 2nd line anti-tuberculosis medications, including drug-induced hepatitis, are well known. Although prothionamide (PTH) is one of the most useful anti-TB medications and although TB medication-induced acute hepatitis is a severe complication, there are only a few published case reports about prothionamide induced hepatitis. In this case report, a 22 year old male was diagnosed with pulmonary MDR-TB and was administered 2nd line anti-TB mediations, including PTH. Afterwards, he had a spiking fever and his liver enzymes were more than 5 times greater than the upper limit of the normal range. He was then diagnosed with drug-induced hepatitis by liver biopsy. His symptoms and liver enzyme elevation were improved after stopping PTH. Accordingly, we report this case of an association between PTH and acute hepatitis.

• Korean Journal of Pharmacognosy
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• v.39 no.3
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• pp.199-202
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• 2008

A high performance liquid chromatographic (HPLC) method for the simultaneous determination of hesperidin and glycyrrhizin was established for the quality control of traditional herbal medicinal preparation, Pyungwi-san (PWS). Separation and quantification were successfully achieved with a Waters XTerra RP18 column ($5{\mu}m$, 4.6 mm I.D. ${\times}$ 150 mm) by gradient elution of a mixture of acetonitrile and water containing 0.03% phosphoric acid (pH 2.03) at a flow rate of 1.0 ml/min. The diode-array UV/vis detector (DAD) was used for the detection and the wavelength for quantification was set at 230 nm. The presence of hesperidin and glycyrrhizin in this extract was ascertained by retention time, spiking with each authentic standard and UV spectrum. All four compounds showed good linearity $(r^2>0.995)$ in a relatively wide concentration ranges. The R.S.D. for intra-day and inter-day precision was less than 7.0% and the limits of detection (LOD) were less than 60 ng. The mean recovery of each compound was 99.0-105.6% with R.S.D. values less than 4.0%. This method was successfully applied to the determination of contents of hesperidin and glycyrrhizin in three commercial products of PWS. These results suggest that the developed HPLC method is simple, effective and could be readily utilized as a quality control method for commercial PWS products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.8
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• pp.1231-1235
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• 2010

The method for residue analysis of four sulfonylurea pesticides, rimsulfuron, ethametsulfuron-methyl, tribenuron-methyl and chlorimuron-ethyl was examined and analyzed by HPLC with ODS column ($250\;mm{\times}4.6\;mm$, $5\;{\mu}m$ diameter particle size) which was maintained at $35^{\circ}C$. Mobile phase consisted of solvent A (20 mM $KH_2PO_4$, pH 2.5) and solvent B (acetonitrile). Isocratic elution of the column with 45% solvent A and 55% solvent B at a flow rate of 1 mL/min resulted in retention times of 5.92, 6.54, 9.28, and 14.35 min for rimsulfuron, ethametsulfuron-methyl, tribenuron-methyl, and chlorimuron-ethyl, respectively. All injection volumes were $20\;{\mu}L$. The limit of quantitation was 0.02, 0.01, 0.001, and 0.004 mg/kg for rimsulfuron, ethametsulfuron-methyl, tribenuron-methyl, and chlorimuron-ethyl, respectively. Recovery rate test was performed with three farm products, rice, apple and soybean. Four sulfonylurea pesticides were spiked at concentrations of 0.05, 0.1 and 0.5 mg/kg. The recovery rates were ranged from 86.12% to 116.26% and the standard deviations of all experiments were within 10%.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.755-761
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• 2017

This study was conducted to establish an analytical method using an HPLC system equipped with a photodiode array (PDA) detector for the quality control of raw materials and cosmeceuticals containing fucoxanthin as an active ingredient. The column was octadecyl-functionalized silica gel and the measurement wavelength of the PDA was set to 499 nm. To validate the analytical method, the linearity of the calibration curve, detection limit, reproducibility and recovery rate were investigated and good results were obtained. The correlation coefficient of the calibration curve was 1.000 and the linearity was good in the concentration range of 0.5 ~ 100 ppm. Moreover, the limit of detection (LOD) was 0.1 ppm and the limit of quantification (LOQ) was 0.5 ppm. The results of the peak reproducibility test used for evaluating the system suitability showed that the RSD (n = 5) of the peak area was 2.0% and that of the retention time was 0.09%. In the spiking test, the recovery rate was $101.6{\pm}0.77%$. The fucoxanthin contents of the two kinds of fucoxanthin-containing raw materials were $49.6{\pm}3.3%$ and $1.03{\pm}0.016%$, respectively. In addition, the fucoxanthin content in the test product, which was intended to be 150 ppm, was $156.7{\pm}4.7ppm$. From the above results, it was concluded that this method could be applied to the quantitative analysis of fucoxanthin in cosmeceuticals.

• The Journal of Pediatrics of Korean Medicine
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• v.17 no.2
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• pp.15-26
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• 2003

Objective : There were few reports on the treatment of Adult-onset Still's disease and Diffuse cerebral dysfunction. This oriental medical treatment shows the possibility of healing Adult-onset Still's disease and Diffuse cerebral dysfunction, therefore we announce this. Methods : The acupuncture, herbal medicine, herbal acupucture(Jahageo, Nockyong) therapies were applied for treating this patient's chief symptom(chest discomfort, palpitation, rigidity, mentality change, global aphasia, dysphagia, coughing and sputum) Results : 1. Adult-onset Still's disease is a rare systemic inflammatory disorder of unknown etiology, characterised by salmon-colored rash, intermittent spiking high fever, arthralgia and variety of systemic features. This is one type of Juvenile arthritis. 2. Diffuse cerebral dysfunction is an anoxic-ischemic encephalopathy, and most cause of this is the hypoxia caused by hypotention or respiratory distress. 3. After oriental medical treatments, his chief symptoms were improved. Conclusion : The more study about oriental medical treatment on Adult-onset Still's disease and Diffuse cerebral dysfunction is needed.

• Analytical Science and Technology
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• v.13 no.2
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• pp.258-267
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• 2000

The result of five year's experience on Inter-laboratory Comparison for Analyses of Heavy Metals and Organic Solvent Metabolites in Biological Samples was described. Since 1995, around a hundred laboratories in the Occupational Health have participated this program twice per year by the Industrial Safety and Health Law. Four metals in blood and five organic solvent metabolites in urine were examined. Reference samples were made by spiking standard materials to human blood or urine pools treated previously to give homogeneity and stability for a specific time periods. Some reference samples for organic solvent metabolites were made from workers' urine who were exposed to the organic solvents. Some items such as Lead in blood and Hippuric acid in urine showed good accordance between participants while the other items such as Mercury and N-methylformamide in urine showed poor proficient rate. The results were published in the internet or newspaper to help the consumer of the laboratory's service to get the information on them and to make competition between them. The inter-laboratory's comparison program have done greate role to improve the ability of analysis and reliability of analytical data produced from each laboratory.