• 한국미생물·생명공학회지
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• 제13권3호
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• pp.285-287
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• 1985

To investigate effective constituents of the many taste components in ordinary Korean soy sauce, we analyzed free amino acids, organic acids, free sugars and saline as taste components in ordinary Korean soy sauce, and determined sensory score of the ordinary Korean soy sauce taste with 45 persons of the trained pannels. The relationships between original data transformed with variables and sensory score of the ordinary Korean soy sauce were analyzed by stepwise multiple regression analysis. Eighty five percents of the ordinary Korean soy sauce taste is affected by twenty one kinds (Isoleucine, Leucine, Valine, NaCl, Lactic acid, Alanine, Phenylalanine, Tartaric acid, Sugar(\ulcorner), Proline, Malic acid, Glycine, Tryptophan, Arginine, Glutaric acid, Maltose, Histidine, Glucose, Fructose and Serine) of the taste components by stepwise multiple regression analysis of original data. Eighty one percents of the ordinary Korean soy sance taste is affected by sixteen kinds (Lactic acid, NaCl, Fumaric.Succinic acid, Tyrosine, Tartaric acid, Glycine, Malonic acid, Malic acid, Tryptophan, Glutaric acid, Methionine, Histidine, Cysteine, Maltose, Fructose and (Glutamic acid) of the taste components by stepwise multiple frgression analysis of original data transformed with square root. Eighty five percents of the ordinary Korean soy sauce taste is affected by nineteen kinds (Fumaric.Succinic acid, Lactic acid, Phenylalanine, NaCl, Tyrosine, Sugar(\ulcorner), Tartaric acid, Leucine, Glutaric acid, Methionine, Glycine, Tryptophan, Histidine, Proline, Cysteine, Glutamic acid, Maltose, Threonine and Oxalic acid) of the taste components by stepwise multiple regression analysis of original data transformed with logarithm.

• 분석과학
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• 제14권1호
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• pp.34-43
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• 2001

수소화물생성법-유도결합플라스마-원자방출분광법으로 게르마늄을 분석할 때 보조산으로 phosphoric acid의 사용은 nitric acid, hydrochloric acid, sulfuric acid, perchloric acid, boric acid, tartaric acid, malic acid, oxalic acid, acetic acid, tannic acid, citric acid의 사용보다 높은 수소화물 생성효율을 보였고, 같은 pH영역이라도 phosphate ion이 존재하는 buffer의 사용이 더 높은 생성효율을 보였다. 또한, 2.5M phosphoric acid를 이용한 결과, 시료용액 내에 잔류하는 산이나 공존원소의 영향이 감소하였다. 환원제와 안정제의 농도가 증가할수록 수소화물 생성효율은 증가되었으며, 최대방출세기를 나타내는 산의 세기는 높은 쪽으로 이동했고 농도영역은 넓어졌다. 인산 존재 하에서의 게르마늄의 검출한계는 $0.03{\mu}g/L$이었다.

• 한국미생물·생명공학회지
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• 제28권3호
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• pp.185-187
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• 2000

Instead of using binary HPLC pump which is usually used for the generation of solvent gradient for the analysis of amino acid an isocratic HPLC pump and conventional gra-dient maker were demonstrated to perform such analysis withmuch lower expenses and similar efficiency.

• 한국식품영양과학회지
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• 제32권3호
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• pp.320-324
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• 2003

단백질 구성 아미노산 분석을 위한 효과적인 가수분해 방법을 찾기 위하여 0.3% tryptamine을 함유한 6M formic acid와 6M HCI을 표준 아미노산과 단백질 표준품인 bovine serumn albumin 가수분해에 적용하여 표준아미노산의 회수율과 bovine serum albumin의 아미노산 조성을 분석하였고 GC에 의한 효과적인 아미노산 분석을 위하여 새로운 유도체인 butylthiocarbamyl-trimethylsilyl(BTC-TMS)유도체를 개발하여 분석한 결과는 다음과 같았다 표준아미노산의 회수율은 6M formic acid에 의한 가수분해방법이 6M HCI에 의한 가수분해 방법보다 상당히 정확하였고 특히 산 가수분해에서 tryptamine의 존재하에서도 잘 파괴되는 tryptophan의 경우 formic acid가수분해가 HCI가수분해보다 1.5배정도 높은 회수율을 보였다. Bovine serum albumin의 아미노산 조성을 583 아미노산 잔기로 환산하여 나타내었을 경우도 formic acid에 의한 가수분해가 HCI가수분해 경우보다 훨씬 정확하였고 이 때 tryptophan의 회수율도 훨씬 높게 나타났다. 다만 서열분석에서 분석되지 않는 cystine이 formic acid 가수분해시 분석되고 있어 이에 대한 정확한 검정이 필요하였다. BTC-TMS 유도체는 GC분석시 극성이 다소 낮은 DB-l7 column으로 분리가 잘되었고 재현성도 좋았으나 GC분석을 위한 대부분의 유도체에서와 마찬가지로 몇 가지 아미노산에서 두 개의 peak로 나타나는 결점이 있었다.

• 폴리머
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• 제28권6호
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• pp.519-523
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• 2004

폴리락트산과 상용성을 높이기 위해 전분에 무수 말레산을 그래프팅한 변성 전분을 제조하여 폴리락트산과 혼합하였다. DSC와 TGA 열적거동에서 폴리락트산/변성 전분 혼합체는 폴리락트산에서 관찰되는 172$^{\circ}C$에서의 용융 피크 외에 1$65^{\circ}C$에서 새로운 용융 피크가 관찰되었으며, 열분해 곡선에서는 폴리락트산/변성 전분 혼합체의 분해 온도가 보다 완만하게 감소되는 것으로 나타났다. 또한 기계적 강도의 측정에서는 폴리락트산/변성 전분이 폴리락트산/전분 혼합체와 비교하여 탄성률이 약 12% 증가하였으며, 이는 SEM 이미지에서 나타난 바와 같이 폴리락트산과 변성 전분의 계면 접착력이 향상되었기 때문으로 사료된다.

• 한국식품과학회지
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• 제37권6호
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• pp.912-917
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• 2005

전남 지방에서 생산되는 매생이를 채취하여 이화학적 성분을 조사하였다. 일반성분은 건물기준 탄수화물이 53.65%로 가장 많이 함유하고 있었고, 조단백질 31.76%, 회분 13.58%와 조 지방이 1.01%로 나타났다. 매생이에 주로 함유되어 있는 무기성분으로는 Na>Mg>Ca>K>P 순으로 나타났으며 Se도 검출되었다. 유리당은 총 5종의 유리당(fructose, glucose, sucrose, maltose, galactose)이 분석되었으며 유기산은 l-malic acid, citric acid, tartaric acid, D-malic acid 등 4종이 검출되었다. 매생이의 구성 아미노산은 전체적으로 고루 함유되어 있었고 그 중 glutamic acid, aspartic acid와 alanine이 전체의 36.2%를 차지하였다. 매생이에 함유된 주요 지방산으로는 palmitic acid, linolenoc acid, stearidonic acid 순이었으며 고도 불포화지방산이 전체의 58.37%를 차지하고 있었다.

• 한국산업보건학회지
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• 제9권1호
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• pp.23-40
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• 1999

The analysis of thiodiglycolic acid in urine has been used as an index of biological exposure to vinyl chloride. Unfortunately thiodiglycolic acid has a strong hydrophilic character, because it has two carboxylic groups, so that it can only be extracted with organic solvent with a great difficulty. Underivatized thiodiglycolic acid tends to tail because of non-specific interaction with the inert support. Therefore, esterification is the obvious first choice for derivatization of thiodiglycolic acid, particularly for gas chromatography. In this study, the focus of interest is to compare two method of esterifications (methylation and silylation). Methylation is to make the methyl ester of thiodiglycolic acid by reaction with diazomethane. Silylation is to make the trimethylsilyl ester of thiodiglycolic acid by reaction with N-trimethylsily-ldiethylamine. The results and conclusions are as the following: 1. The detection limit (sensitivity) of methylated thiodiglycolic acid was $5.00{\mu}g/m{\ell}$ and silylated thiodiglycolic acid was $3.07{\mu}g/m{\ell}$ by gas chromatography with flame ionization detector. 2. The optimal liquid-liquid extraction of thiodiglycolic acid was as following: To each of the tubes, $15m{\ell}$ of urine, concentrated sulfuric acid (pH 1 - 2) and 5 gsodium sulfate were added. The samples was extracted three times with $5m{\ell}$ ethylacetate each time. 3. The methylated thiodiglycolic acid was more stable than silylated thiodiglycolic acid in extractional solvent which contained humidity. 4. The precision (pooled coefficient of variation for 4 days) of the analysis was 0.07324 in methylated thiodiglycolic acid with external standard calibration, and 0.07033 in methylated thiodiglycolic acid with internal standard calibration. 5. The precision (pooled coefficient of variation for 4 days) of the analysis was 0.10914 in silylated thiodiglycolic acid with external standard calibration, and 0.13602 in silylated thiodiglycolic acid with internal standard calibration. From the above results, the analysis of methylated thiodiglycolic acid was more sensitive (limit of detection) than silylated thiodiglycolic acid by gas chromatography. However, the methylated thiodiglycolic acid was stable in the humidity and was separated sharply on chromatogram. Also, analysis of methylated thiodiglycolic acid was more precise (pooled coefficient of variation for 4 days) than silylated thiodiglycolic acid. In conclusion, it is established that the analysis of methylated thiodiglycolic acid is appropriate for biological monitoring of exposure to vinyl chloride.

• 한국미생물·생명공학회지
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• 제30권1호
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• pp.21-25
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• 2002

토양으로부터 분리한 Bacillus sp. YJ-63으로부터 항진균성 항생물질을 분리하여 그 구조를 분석한 결과는 다음과 같다. 항생물질은 7개의 $\alpha$-amino acid와 1개의 $\beta$-amino acid가 결합한 환상구조를 가지는 iturin E 계에 속하며 특히. $\beta$-amino acid의 methylene 수가 기존의 iturin E 보다 더 많은 것으로 나타났다.

• 한국연초학회지
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• 제9권1호
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• pp.57-64
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• 1987

The pyrolysis of geometrical isomers of 9-octadecenoic acid were conducted at $600^{\circ}C$ under nitrogen, and its pyrolytic behaviors were investigated. The pyrolytic products of both fatty acids, cis-9-octadecenoic acid(oleic acid) and trans-9-octadecenoic acid(elaidic acid), were analyzed using a gas chromatograph and GC/MS spectrometer. Twenty-seven different compounds were identified from these pyrolyzates, and the chief products of them were ketones, alcohols and aromatic hydrocarbons. And also, the pyrolytic mechanisms of two geometrical isomers of this fatty acid were discussed by a comparison of experimental results.

• 한국자원식물학회지
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• 제11권2호
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• pp.202-209
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• 1998

Through total fatty acid analysis by the Gas chromatography, 17 different fatty acids were identified from the sap extracted from bark of Korean Rhus(Anacardiaceae), six species. Linoleic acid(C18 :2) and oleic acid(C18 : 1) were identified as major fatty acids for the species investigated, but except in R. chinensis.In the fatty acid composition for the species, one or two specific-fatty acid was detected, and its could be utilized as a useful taxonomic character.The result of cluster analysis by the 22 reliable characters in the fatty acid composition suggested first group was R.trichocarpa and R. succedanea, the second group, R.verniciflua, R.ambgua and R. sylvestris, but R.chinensis was a greatly independent species. The possible chemotaxonomic application of the fatty acid composition of bark in the genus Rhus was discussed.