• Journal of Food Hygiene and Safety
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• 제20권1호
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• pp.64-68
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• 2005

An analytical method of nine synthetic foods colors in Korea, Japan, Joint FAO/WHO Expert Committee of Food Additives (JECFA), and USA were compared. Contents of water insoluble matter in synthetic food colors tested were not different by general test methods of various organs. Contents of chloride and sulfate salts in Food Green No.3, Food Red No.3, Food Blue No.2, and Food Yellow No.4 slightly differed in various methods, and but up to the standard, and general test methods of JECFA and USA needed far more time. For the measurement of arsenic contents in food colors, colorimetric method in Korea and Japan, and silver diethyldithiocarbamate colorimetric method in USA and JECFA were used, but the standards of them were different. Content of heavy metals was up to the standard, but the methods were used colorimetric method in Korea, atomic absorption method in Japan, and both methods in JECFA and USA.

• Journal of Food Hygiene and Safety
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• 제19권4호
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• pp.171-175
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• 2004

An analytical method of nine synthetic food colors in Korea, Japan, Joint FAO/WHO Expert Committee of Food Additives (JECFA), and USA were compared. Contents of water insoluble matter in synthetic food colors tested were not different by general test methods of various organs. Contents of chloride and sulfate salts in Food Green No.3, Food Red No.3, Food Blue No.2, and Food Yellow No.4 slightly differed in various methods, and but up to the standard, and general test methods of JECFA and USA needed far more time. For the measurement of arsenic contents in food colors, colorimetric method in Korea and Japan, and silver diethyldithiocarbamate colorimetric method in USA and JECFA were used, but the standards of them were different. Content of heavy metals was up to the standard, but the methods were used colorimetric method in Korea, atomic absorption method in Japan, and both methods in JECFA and USA.

• Korean Journal of Food Science and Technology
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• 제37권6호
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• pp.918-921
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• 2005

Quantitative analysis of flavonoids in commercial propolis extract products were compared by three colorimetric methods; aluminum chloride method, dinitrophenylhydrazine method and aluminum nitrate method, Aluminum nitrate method in Korea Health Supplement Food Code was proved to be specific only for flavones and flavonols same as aluminum chloride method, while dinitrophenylhydrazine method was specific for flavanones and dihydroflavonols. Therefore, the sum of flavonoid contents determined by 2,4-Dinitrophenylhydrazine method and aluminum nitrate method may represent the real content of total flavonoids. As for the 25 commercial propolis extract products examined, the contents of flavonoid varied from 2.15% to 9.53% except for one product.

• Korean Journal of Microbiology
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• 제18권4호
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• pp.155-160
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• 1980

Microorgansims utilizing anionic detergent as their carbon and sulfur sources were isolated from soils and sewages. Alkyl benzene sulfonate (Hiti) and sodium dodecyl sulfonate (SDS) were the detergent compound tested. Three of these isolated microorganisms were identified as Pseudomonas spp. and the others asKlbsiella, Enterobacter and Acinetobacter. Biodegradation rate of the detergents and growth rate of Acinetobacter Strain II-8, Pseudomonas strain H-3-1 and 554 among six isolated microorganisms were investigated with colorimetric, warburg manometric, and ultraviolet absorption analyses. By performance of 4 serial successive tranfer to new culture broth for the purpose of adaptation method, ABS and SDS could be degraded to far more than 40%-60% and 70%-75%, respectively. However the employment of nonadaptation method, ABS and SDS were degraded to 30%-45% and 45%-65%, respectively. In another words, detergents degradation ability was increased to a certain extent by successive transfer to the new minimal media. We would conclude that the development of adaptation was effective in the removal of recalcitrant compounds.

• Restorative Dentistry and Endodontics
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• 제37권2호
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• pp.84-89
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• 2012

Objectives: This study analyzed the difference in color caused by different thickness in enamel layer of composite resins when applied with single and layering placement technique, and evaluated if the results agreed with the shade guide from the manufacturers to verify reliability of the color matching process of the manufacturers. Materials and Methods: For single composite resin samples, 6 mm diameter and 4 mm thickness cylindrical samples were fabricated using Ceram-X mono (DENTSPLY DeTrey) and CIE $L^*a^*b^*$ values were measured with spectrophotometer. Same process was done for layering composite resin samples, making 3 dentinal shade samples, 4 mm thickness, for each shade using Ceram-X duo (DENTSPLY DeTrey) and enamel shade resins were layered in 2 mm thickness and CIE $L^*a^*b^*$ values were measured. These samples were ground to 0.2 mm thickness each time, and CIE $L^*a^*b^*$ values were measured to 1 mm thickness of enamel shade resin. Results: Color difference (${\Delta}E^*$) between single and layering composite resin was 1.37 minimum and 10.53 maximum when layering thicknesses were between 1 mm and 2 mm and 6 out of 10 same shade groups suggested by manufacturer showed remarkable color difference at any thickness (${\Delta}E^*$ > 3.3). Conclusion: When using Ceram-X mono and duo for composite resin restoration, following the manufacturer's instructions for choosing the shade is not appropriate, and more accurate information for Ceram-X duo is needed on the variation and expression of the shades depending on the thickness of the enamel.

• Journal of Korean Society of Forest Science
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• 제96권5호
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• pp.580-584
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• 2007

Actinidia arguta extracts obtained from three cultivars ('Sae-Han', 'Dae-Sung', and 'Chil-Bo') were assayed for their antioxidant properties and nutritional composition. Antioxidant activity of the extracts was evaluated using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method. Total phenolic contents of the extracts were determined by the Folin-Ciocalteu method. Vitamin C (L-ascorbic acid) content measured by a colorimetric method and reducing sugar content estimated by dinitrosalicylic acid (DNSA) method. Crude extracts from A. arguta 'Sea-Han' showed the most potent radical-scavenging activity showing 86.55% at 10 mg/ml. The DPPH radical scavenging activity of extracts and solvent fractions from Sea-Han cultivar was in decreasing order of EtOAc fraction>BuOH fraction>$CH_2Cl_2$ fraction>hexane fraction, among which EtOAc fraction showed the highest antioxidant activity (87.51 % at 5 mg/ml). Total phenolic contents in A. arguta 'Sae-Han', 'Dae-Sung' and 'Chil-Bo', were 32.93, 28.23, and 25.60 mg/g, respectively. Vitamin C contents of them were 840.57, 578.81 and 730.10 ug/g, respectively.

• Food Science and Biotechnology
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• 제16권3호
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• pp.477-481
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• 2007

Fourier transform near-infrared (FT-NIR) spectroscopy and partial least squares (PLS) regression were used to predict the amylose content of polished rice. Spectral reflectance data in a wavelength range of 1,000 to 2,500 nm were obtained with a commercial spectrophotometer for 60 different varieties of Korean rice. For a comparison of this spectroscopic method to a standard chemical analysis, the amylose contents of the tested rice samples were determined by the iodine-blue colorimetric method. The highest correlation for the rice amylose ($R^2=0.94$, standard error of prediction=0.20% amylose content) was obtained when using the FT-NIR spectrum data pre-treated with normalization, the first derivative, smoothing, and scattering correction.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 한국조명전기설비학회 2007년도 춘계학술대회 논문집
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• pp.166-169
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• 2007

최근에 정부의 "15/30 LED조명 보급정책"에 힘입어 개발된 8W급 조명용 LED광원의 CIE 색도좌표 (chromaticity coordinate)와 주파장(dominant wavelength)등을 측정 고찰 하였다. 적색(R), 녹색(G), 청색(B), 백색(W)순으로 주파장은 각각 620[nm], 531[nm], 465[nm], 579[nm]이고, 자극순도(excitation purity)는 0.98, 0.82, 0.97, 0.15이며, 휘도순도(colorimetric putity)는 45[%], 16[%], 279[%], 6[%]로 나타났다. Power LED의 최적배치 설계로서, 특히 백색 LED광원의 경우 백열전구(15 lm/W)에 비해 3배 이상의 높은 효율(47.71m/W)을 보였고, 배광측정에서는 78.7%의 효율로 나타났다. 현재 LED광원은 MR16이나 베이스 타입 등의 형태로 제작하여 스탠드, 복도등, 비상유도등, 침실용 등의 용도에 사용되고, 일부는 LED의 원형이나 면(flat)타입으로 가로등이나 투광등으로도 활용되고 있다. 따라서 이들에 대한 각각의 특성들을 제시해 둘 필요성인 인지되어 국내 최초로 개발된 R/G/B/W 8W급 LED광원에 대한 기본적인 광특성 결과를 얻었으며, 이중에서 HB 백색 LED램프의 색도좌표 값을 얻어 CIE표준광과의 색도좌표(x, y) 위치를 비교 검토할 수 가 있었다.

• Archives of Pharmacal Research
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• 제14권3호
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• pp.207-216
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• 1991

Pseudixus japonicus agglutinin (PJA) was isolated. And its characteristics were compared with those of concanavalin A (Con A). PJA is a glycopritein composed of 49.3% carbohydrate and 50.7% protein which had relatively high percentages of glutamic acid, aspartic acid and phenylalanine residues. The hemagglutinating activity of PJA was approximately one-eighth of that of Con A when tested with mouse crythrocytes. PJA failed to simulate the proliferation or transformation of human and mouse lymphocytes in contratst to Con A. PJA and Con A showed cytotoxicities against SNU-1 (human stomach cancer cells), SNU-CI (human colon cancer cells) and mouse Sarcoma 180 cells when tested by 3-(4, 5-dimethyl thiazol-2-yl)2. 5-diphenyl tetrazolium bromide (MIT) colorimetric assay. The antitumor activity of the lectin in vivo was also tested in Sarcoma 180 bearing mice. There was no significant difference in prologation of lifc span of the mice after the treatment with PJA and Con A for 10 consecutive days.

• Journal of Microbiology and Biotechnology
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• 제30권11호
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• pp.1739-1749
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• 2020

Exopolysaccharide produced by the yeast Papiliotrema flavescens, isolated from wine grape berries of Champagne vineyard, was investigated for both chemical and functional characterization. SECMALLS and colorimetric assay analyses showed that the EPS is a high M_W heteropolymer (2.37 × 10⁶ g/mol) majorily consisting of mannose, glucose, xylose and glucuronic acid as monosaccharide constituents, with two substituents (sulphate and phosphate groups), and a minor protein moiety. Structural enchainment of these carbohydrates based on methylation, GC-MS and NMR analyses revealed a linear main backbone built up of α-(1 → 3)-D-mannopyranosyl residues on which are branched side chains consisting of a single β-D-glucopyranosyluronic acid residue and β-(1 → 2)-xylopyranoses (2-5 residues). Suggestion of some xylopyranose side chains containing a mannose residue at the nonreducing terminal end was also proposed. This is first report on EPSs from the grape P. flavescens yeast with such structural characteristics. Furthermore, investigations for valuating the application performance of these EPS in relation with their structural features were carried out in 8% alcohol experiment solutions. Very exceptional viscosifying and foaming properties were reported by comparison with commercial biopolymers such as Arabic, gellan and xanthan gums. The intrinsic properties of the natural biopolymer from this wild grape-associated P. flavescens yeast make it a potential candidate for use in various biotechnology applications.