• Title/Summary/Keyword: GC analysis

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Cause Analysis in Candle Fire Investigation (양초화재 원인 감정에 관한 연구)

  • Han, Dong-Hun
    • Fire Science and Engineering
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    • v.30 no.3
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    • pp.104-109
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    • 2016
  • Candle fires do not occur frequently, but can easily result in death. In this study, the thermal characteristics of candles and conditions and debris of candle fires were investigated to determine the causes of candle fires. The rates of decrease in weight of 10 candles were measured and found to be between 2.6 g/h and 6.7 g/h. Most candle fires are caused by the ignitiong of combustible materials close to them. The temperature near a candle ranges from about $200^{\circ}C$ to $400^{\circ}C$ at a distance of 1 cm and low ignition temperature materials such as papers can easily catch fire. The melting temperature of candles ranges between $50^{\circ}C$ and $70^{\circ}C$ and their major chemical components are fatty acids and normal hydrocarbons (over C20). Using pretreatment conditions involving the use of activated charcoal strips at $150^{\circ}C$ for 16 hours, the fire debris including candle residues were analyzed using a Gas-chromatograph/Mass-spectrometer (GC/MS).

A Study on Detection of Residual Solvent, Ethoxyquin and Color Stability in Oleoresin Paprika Extracts (파프리카 추출물의 색소안정성과 Ethoxyquin 및 잔류용매 검출)

  • Lee, Seon-Ok;Kyung, Suk-Hun;Park, Kil-Dong;Kang, Hee-Gon;Park, Joo-Sung;Lee, See-Kyung
    • Applied Biological Chemistry
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    • v.45 no.2
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    • pp.77-83
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    • 2002
  • Effects of ethoxyquin on the color stability of oleoresin paprika extracts and amount of residual ethoxyquin, a color stabilizer, in commercial extracts were determined. The oleoresin paprika extracts dissolved in ethanol gave the highest maximum photo-absorbency at 444-458 nm, with the color index of United States product 2-6 times higher than that produced in India. The residual solvents in oleoresin paprika extracts were mainly acetone and methanol, although some other extracts also contained small amounts of hexane. HPLC analysis was determined as a proper analytical method for residual ethoxyquin assay in the oleoresin paprika extracts, particularly when hexane was used as a solvent. The residual ethoxyquins were detected in the extracts produced in US and Spain which had relatively high color indices.

Survey of Contaminants of Bound 3-MCPD in Food (식품 중 결합형 3-MCPD 오염실태조사)

  • Kong, Young-Woon;Park, Sung-Kug;Seo, Jung-Heok;Kim, Dong-Sul
    • Journal of Food Hygiene and Safety
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    • v.25 no.4
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    • pp.289-293
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    • 2010
  • 3-MCPD created in manufacture process was regulated in our country about soy sauce and HVP. The latest paper reported that Bound 3-MCPD is created as intermediate. Germany common risk assesment reported that Bound 3-MCPD must be reduced because Bound 3-MCPD can be created in estimation circle when this is hydrolyzed in human body, but the data about the toxity of Bound 3-MCPD is lack. Therefore, We analysis about 209 items food such as soy sauce, seasoning food and meat-eating manufactured goods using bound 3-MCPD analysis method developed recently. As result of survey, bound 3-MCPD detected in 8 items among 44 traditional sauce (0.02~0.28ppm), 8 of soup 12 items (0.01~0.96ppm), in 22 items of sauce 60 items (0.01~0.55ppm), in 16 items of meat-eating manufactured foods 30 items (0.04~0.18ppm), in 20 items of snack cookies 28 items (0.09~1.43ppm), in 8 in roasted oil foods 10 items (0.04~1.22ppm), in 6 items of peanut processed food 10 items (0.06~0.25ppm), in 1 of vegetable cream 15 items (0.05ppm). Detected level was lower than the result of monitored by other countries.

Invitro and Virtual Screening of Bioactive Molecule from Mycelium of Trichoderma atroviride Inhibit the UDP-3-O-(R-3-hydroxymyristoyl)-N-acetylglucosamine Deacetylases (LpxC) for Treatment of Bacterial Infection

  • Saravanakumar, Kandasamy;Park, Cheol-Ho;Wang, Myeong-Hyeon
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2018.04a
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    • pp.67-67
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    • 2018
  • Trichoderma species are a rich source of metabolites, but less known for biomedical potential. This work deals with antibacterial and antioxidant potentials of intracellular non-cytotoxic metabolites, extracted from Trichoderma atroviride (KNUP001). A total of 53 fractions was collected by column chromatography and tested for cytotoxicity by MTT assay. Only one fraction (F41) was found to be non-toxic to Vero cells with $95.4{\pm}0.61%$ of survival. The F41 was then subjected to chemical analysis, antibacterial and antioxidant assays. The F41 at $500{\mu}g.ml^{-1}$ showed the total antioxidant of $48.70{\pm}2.90%$, DPPH radical scavenging activity of $37.25{\pm}2.25$, nitric oxide (NO) radical scavenging activity of $54.55{\pm}1.95$ and $H_2O_2$ radical scavenging activity of $43.75{\pm}3.21$. The F41 at $25{\mu}g.ml^{-1}$ displayed antibacterial activity against E. coli ($14.25{\pm}0.2mm$), P. mirabilis ($10.4{\pm}0.6mm$), S. dysenteriae ($18.6{\pm}03mm$), S. paratyphi A ($14.1{\pm}1.1mm$), E. aerogenes ($5.6{\pm}0.4mm$) and S. marcescens ($14.25{\pm}0.2mm$). GC-MS analysis revealed the dominant presence of oleic acid C 18.1 (63.18%), n-hexadecanoic acid (6.17%), and ethyl oleate (4.93%) and potent molecules such as 8-[(2E)-2-(3-hydroxybenzylidene)hydrazinyl]-1,3,7-trimethyl-3,7-dihydro-1H-purine-2,6-dione, 2-(Dimethylamino)ethyl (1Z)-N-hydroxy-2-(4-morpholinyl)-2-oxoethanimidothioate, Fluorene in the F41, and virtual study revealed that these molecules are likely responsible for the antibacterial activities of F41. Hence, further investigation deserves on purification and characterization of the active metabolites from T. atroviride strain KNUP001 towards developing molecular leads to effective antibacterial drugs, and non-toxic to host cells.

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Analysis of Fatty Acid Composition and Effects of Pumpkin Seed Oil on Human Umbilical Vein Endothelial Cells (호박씨유의 지방산 성분 분석 및 Human Umbilical Vein Endothelial Cell에 미치는 영향 연구)

  • Kim, Kyoung Kon;Kang, Yun Hwan;Kim, Dae Jung;Kim, Tae Woo;Lee, Jeong Il;Choe, Myeon
    • Journal of the East Asian Society of Dietary Life
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    • v.24 no.3
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    • pp.351-358
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    • 2014
  • Pumpkin seed oil (PSO) was investigated for its parasite elimination activity and efficacy in treating disorders of the prostate gland and urinary bladder. We confirmed the composition of PSO and identified its ability to improve vessels. Gas chromatography coupled with mass spectrometric (GC-MS) system was used for PSO composition analysis. Cytotoxicity and cell proliferation were confirmed by Cell Counting Kit-8 (CCK-8) assay. Nitric oxide(NO) production was measured with Griess reagent, and intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 mRNA expression levels were measured by reverse transcription polymerase chain reaction (RT-PCR). As a result, PSO revealed the presence of several components such as linoleic acid, oleic acid, palmitic acid and stearic acid. Cytotoxic effects of PSO were not observed, and PSO increased nitric oxide production in human umbilical vein endothelial cells (HUVEC). Additionally, TNF-${\alpha}$-induced cell proliferation and ICAM-1 expression in HUVEC were inhibited by PSO treatment, whereas VCAM-1 expression was not significantly reduced. Taken together, these results show that PSO is worthy of study as a candidate food material for improvement of vascular disease.

Headspace Volatile Compounds of Krill Reaction Flavor and Its Application to Teriyaki Sauce (크릴반응향의 휘발성 향기 성분 및 데리야끼소스의 적용)

  • Kim, Kyoung-Myo;Park, Hyun-Joo;Nam, Min-Hee;Kim, Seong-Bong;Chun, Byung-Soo;Lee, Yang-Bong
    • Culinary science and hospitality research
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    • v.19 no.3
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    • pp.105-115
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    • 2013
  • Maillard reaction flavors had been tried by using krill hydrolysate and precursors in order to develop Teriyaki sauce with the reaction flavors. Also, the study for applying krill to Teriyaki sauce had been tried by using krill instead of eel bones. To make boiled-type and grilled-type reaction flavors, krill hydrolysate was used with other precursors such as serine, glucose and glucosamine. In the dynamic analysis of headspace volatile compounds, 20 mL reaction flavor was analyzed by the combined system of purge & trap, automatic desorber, gas chromatography and mass selective detector. Three kinds of Teriyaki sauce were developed with reaction flavor, krill and eel bones, and their products were evaluated by 10 items of cooked vegetables, cooked potatoes, boiled shrimp, grilled shrimp, fishy smell, pungent aroma, burned smell, sweety aroma, chemical smell, mud smell and preference. In the results of headspace analysis, 35 and 33 volatile compounds were identified from grilled-type and boiled-type reaction flavors. Grilled-type had sulfur-containing, aliphatic compounds, alcohols, ketones, pyrazines, and other aromatic compounds, and grilled-type had aldehydes, furans, other nitrogen-containing compounds. In the sensory evaluation of Teriyaki sauce, the items of roasted shrimp and sweety aroma showed significant differences for grilled-type application to Teriyaki sauce. The above results show the possible application of grilled-type reaction flavor to Teriyaki sauce.

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Volumetric accuracy of cone-beam computed tomography

  • Park, Cheol-Woo;Kim, Jin-ho;Seo, Yu-Kyeong;Lee, Sae-Rom;Kang, Ju-Hee;Oh, Song-Hee;Kim, Gyu-Tae;Choi, Yong-Suk;Hwang, Eui-Hwan
    • Imaging Science in Dentistry
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    • v.47 no.3
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    • pp.165-174
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    • 2017
  • Purpose: This study was performed to investigate the influence of object shape and distance from the center of the image on the volumetric accuracy of cone-beam computed tomography (CBCT) scans, according to different parameters of tube voltage and current. Materials and Methods: Four geometric objects(cylinder, cube, pyramid, and hexagon) with predefined dimensions were fabricated. The objects consisted of Teflon-perfluoroalkoxy embedded in a hydrocolloid matrix (Dupli-Coe-Loid TM; GC America Inc., Alsip, IL, USA), encased in an acrylic resin cylinder assembly. An Alphard Vega Dental CT system (Asahi Roentgen Ind. Co., Ltd, Kyoto, Japan) was used to acquire CBCT images. OnDemand 3D (CyberMed Inc., Seoul, Korea) software was used for object segmentation and image analysis. The accuracy was expressed by the volume error (VE). The VE was calculated under 3 different exposure settings. The measured volumes of the objects were compared to the true volumes for statistical analysis. Results: The mean VE ranged from -4.47% to 2.35%. There was no significant relationship between an object's shape and the VE. A significant correlation was found between the distance of the object to the center of the image and the VE. Tube voltage affected the volume measurements and the VE, but tube current did not. Conclusion: The evaluated CBCT device provided satisfactory volume measurements. To assess volume measurements, it might be sufficient to use serial scans with a high resolution, but a low dose. This information may provide useful guidance for assessing volume measurements.

Quality Characteristics of Takju, Yakju, Spirit made by Cereal Nuruks (곡류 누룩으로 제조한 탁주, 약주, 증류주의 품질 특성)

  • Jeong, Jae-Hong;Chai, He-Suk;Lee, Yun-Hi;Kim, Jae-Min;Lee, Jeong-Hoon
    • Culinary science and hospitality research
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    • v.21 no.1
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    • pp.267-280
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    • 2015
  • This study was carried out to evaluate the quality characteristics of Takju, Yakju, Spirit made by various cereal Nuruks which were made by Jokuk(whole wheat), Bunkuk(wheat flour), Maekkuk(whole barley). pH, Brix, cell number of yeast, alcohol content, flavors, organic acid, and sensory evaluation of brews were employed to analyze current study. Results showed that pH value of brews during fermentation decreased, while Brix value increased. In addition, alcohol contents increased up to 11 day's fermentation, but there were no significant differences among Jokuk, Bunkuk and Maekkuk(p<0.05). Cell numbers of yeast dramatically increased up to 5 day's fermentation, and then decreased. After 13 day's fermentation cell numbers of yeast were similar among Jokuk, Bunkuk and Maekkuk. In terms of analysis of flavor components, acetone and n-amyl alcohol were not detected in all brews, however fusel oil level was 494.65 mg/L in Maekkuk, and 525.4 mg/L in Bunkuk. Lactic acid showed the highest level in organic acid analysis. Furthermore, Jokuk and Maekkuk showed highest score in Takju, Maekkuk showed highest score in Yakju in sensory evaluation, although Jokuk, Bunkuk, and Maekkuk revealed similar score in spirit.

Mechanism of Action of Prochloraz and Triadimefon on Valsa ceratosperma (Prochloraz 와 Triadimefon의 사과나무 부란병균(腐爛病菌)에 대(對)한 작용기작(作用機作))

  • Hong, Jong-Uck;Lee, Dong-Jin;Kim, Jang-Eok
    • Applied Biological Chemistry
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    • v.32 no.3
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    • pp.270-277
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    • 1989
  • In order to elucidate the action mechanism of prochloraz and triadimefon, the mycelia of the Valsa ceratosperma were treated with the compounds in vitro. Analysis by GLC of the sterol extract from Valsa ceratosperma mycelia revealed one major peak and two minor peaks. Their relative retention time(RRT) relative to chloresterol were 1.29, 1.48 and 1.82, The compounds with RRT 1.29 and RRT 1.82 were identified as ergosterol and 24-methylenedihydrolanosterol by GC/MS, respectively. Five ppm of prochloraz and triadimefon applied to mycelia caused decrease in ergosterol content, whereas increase in 24-methylenedihydrolanoserol content in mycelia. The longer treatment time and the higher concentrations of the chemicals resulted in the greater decrease in ergosterol and the greater increase in 24-methylenedihydrolanosterol. Based on the analysis, it is considered that the two chemicals inhibit the ergosterol biosynthesis in Valsa ceratosperma by blocking C-14 demethylation as found previously in other fungi arid yeasts.

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A Study on the Cookery of Andong Sikhe(II) -Physicochemical Changes upon Fermentation Temperature and Time- (안동식혜의 조리법에 관한 연구(II) -발효온도와 시간에 따른 이화학적 변화-)

  • 윤숙경
    • Korean journal of food and cookery science
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    • v.4 no.2
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    • pp.21-30
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    • 1988
  • To study the optimum fermentation and aging conditions for preparation of Andong Sikhe which is consumed in the northern Kyungbuk province as a traditional beverage, Sikhe were fermented and aged at $12^{\circ}C$ for 48, 60 and 72hrs and fermented at 40, 50. and $60^{\circ}C$ for 2, 3, and 4hrs and then aged at $12^{\circ}C$ for 20 hrs, Non-volatile organic acids and free sugars were analyzed by GC and HPLC, respectively, and sensory test was performed. Sikhe fermented at $40^{\circ}C$ for 3hrs and aged at $12^{\circ}C$ for 20hrs was evaluated the most favorable one by sensory test. This Sikhe had the lowest pH 4.6~4.7 among sample and 14.6% of sugar. The sugar content was lower than those of Sikhe Fermented at $50^{\circ}C$ and $60^{\circ}C$. In organic acid analysis, the concentration of malate 67.53%/mg in this Sikhe was the highest. Lactate, succinate and maleate were produced more in this Sikhe than in any other ones. Oxalate which was existed before fermentation was not found in the Sikhe, and a small amounts of citrate and fumarate were produced. In sugar analysis, maltose was dominant 11.56%, glucose 1.25% and fructose 0.45%.

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