• Food Science and Biotechnology
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• 제18권3호
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• pp.700-705
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• 2009

In this study, the volatile compounds in 9 commercial fermented soybean pastes were extracted and analyzed by headspace-solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS), respectively. A total of 63 volatile components, including 21 esters, 7 alcohols, 7 acids, 8 pyrazines, 5 volatile phenols, 3 ketones, 6 aldehydes, and 6 miscellaneous compounds, were identified. Esters, acids, and pyrazines were the largest groups among the quantified volatiles. About 50% of the total quantified volatile material was contributed by 5 compounds in 9 soybean paste samples; ethyl hexadecanoate, acetic acid, butanoic acid, 2/3-methyl butanoic acid, and tetramethyl-pyrazine. Three samples (CJW, SIN, and HAE) made by Aspergillus oryzae inoculation showed similar volatile patterns as shown in principal component analyses to GC-MS data sets, which showed higher levels in ethyl esters and 2-methoxy-4-vinylphenol. Traditional fermented soybean pastes showed overall higher levels in pyrazines and acids contents.

• 생약학회지
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• 제35권1호통권136호
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• pp.62-79
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• 2004

Cell-scattering is a phenotypic change easily observed in most epithelial cells treated with Hepatocyte Growth Factor /scatter Factor (HGF/SF) or phorbol esters (PKC-activators). Recent studies have shown the possibilities to use as therapeutic materials of HGF/SF or non tumor promoting phorbol esters for liver disease, cancer and AIDS. In this study, we tested a cell-scattering activity of 534 methanol extracts from plants inhabiting in Korean peninsula using the phenotype-based assay system. Nine Active extracts were detected : Daphne genkwa, Daphne kiusiana, and Aleurites fordii showed high activity (+++), Euphorbia sieboldiana and Rhodotypos scandens showed medium activity (++), Sambucus sieboldiana var. pendula, Catalpa bignonioides, Sambucus sieboldiana and Lycoris squamigera showed low activity (+). Furthermore, the effects of these active materials in the culture cells were investigated with biochemical studies.

• Bulletin of the Korean Chemical Society
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• 제13권4호
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• pp.407-413
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• 1992

The chromatographic separation of the stereoisomers of the N-(3,5-dinitrobenzoyl) derivatives of fifteen dipeptide methyl esters and nine dipeptide alkyl esters was investigated on three different chiral stationary phases derived from N-acylated ${\alpha}-arylalkylamines$. Two of these CSPs contain second stereogenic centers. These secondary stereogenic centers of CSPs were proposed to provide secondary effects in terms of chiral recognition. From the elution orders of the four dipeptide stereoisomers and the separation factors of the enantiomeric pairs of the N-(3,5-dinitrobenzoyl) derivatives of the dipeptide alkyl esters having different alkoxy substituents, it was proposed that the intercalation of the alkoxy substituents of dipeptide derivatives between the connecting arm of CSPs may control the magnitude of chiral separations of dipeptide derivatives.

• Bulletin of the Korean Chemical Society
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• 제22권2호
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• pp.199-204
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• 2001

A Cryptate (221) having a short alcohol pendant (2) was metallated with europium(Ⅲ) in anhydrous condition, and its hydrolytic activity for phosphate esters at neutral pH was examined. While the activity for the phosphate diester and monoester is comparable to that of the parent metal complex [1Eu]3+, its hydrolytic activity towards a phosphate triester is significantly suppressed. Potentiometric titration and luminescence spectroscopic studies for the equilibrium behavior of the complex in solution suggest that a dimer formation through the metal hydroxides as well as the pendant alcohol is likely to happen. The low hydrolytic activity for the triester seems to be associated with the dimer formation.

• 한국식품과학회지
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• 제10권4호
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• pp.409-414
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• 1978

숭어 난유(卵油)의 지질조성(脂質組成)을 조사(調査)한 결과(結果)를 보면 다음과 같다. 1 숭어의 각조직(各組織)의 지질성분(脂質成分)은 상이(相異)하였다. 즉 근육(筋肉), 난(卵) 및 간(肝)에서 추출(抽出)한 지질주요성분(脂質主要成分)은 각각(各各) triglyceride, wax ester, 유리지방산(遊離脂肪酸)였다. 2. 숭어난(卵)의 지질함량(脂質含量)은 약(約) 20.5%였고, 그 지질(脂質)의 요-드가(價)는 118, 불감화물의 양(量)은 38.7%였다. 3. 숭어난유(卵油)의 중요지질조성(重要脂質組成)은 wax ester가 59.1%로 제일 많았고, 다음이 극성지질(極性脂質)로 26.9%, 그 다음이 triglyceride로 9.0%였으며, Sterol은 3.0%였다. 4. Wax ester의 중요(重要)한 지방산조성(脂肪酸組成)을 보면 palmitic acid가 47.5%로 제일 많았으며, 그 다음이 oleic acid로 23.0%, hexadecatrienoic acid가 6.5%, eicosapentaenoic acid가 4.0%였다. 또 triglyceride의 조성(組成)을 보면 palmitoleic acid가 25.1%, oleic acid가 16.7%, palmitic acid가 16.3%, eicosamonoenoic가 7.9%, stearic acid가 5.5%였다. 극성지질(極性脂質)의 경우는 palmitic acid가 35.0%, oleic acid가 24.7%, palmitoleic acid가 6.1%, eicosapentaenoic acid가 5.3%였다. 5. Wax ester의 중요(重要)한 alcohal은 cetyl alcohol(C16:0)가 51.0%로 제일 많았고. 그 다음이 palmitoleyl alcohol(C16:1)로 18.2%, 그 다음이 oleyl alcohol (C18:1)로 10.7%였다. 또 C15:0, C15:1, C17:0, C17:1, C19:1과 같은 기수탄소(奇數炭素) alcohol가 상당량(相當量) 발견(發見)되었다.

• Journal of Microbiology and Biotechnology
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• 제32권6호
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• pp.761-767
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• 2022

EHT1 and EEB1 are the key Saccharomyces cerevisiae genes involved in the synthesis of ethyl esters during wine fermentation. We constructed single (Δeht1, Δeeb1) and double (Δeht1Δeeb1) heterogenous mutant strains of the industrial diploid wine yeast EC1118 by disrupting one allele of EHT1 and/or EEB1. In addition, the aromatic profile of wine produced during fermentation of simulated grape juice by these mutant strains was also analyzed. The expression levels of EHT1 and/or EEB1 in the relevant mutants were less than 50% of the wild-type strain when grown in YPD medium and simulated grape juice medium. Compared to the wild-type strain, all mutants produced lower amounts of ethyl esters in the fermented grape juice and also resulted in distinct ethyl ester profiles. ATF2, a gene involved in acetate ester synthesis, was expressed at higher levels in the EEB1 downregulation mutants compared to the wild-type and Δeht1 strains during fermentation, which was consistent with the content of acetate esters. In addition, the production of higher alcohols was also markedly affected by the decrease in EEB1 levels. Compared to EHT1, EEB1 downregulation had a greater impact on the production of acetate esters and higher alcohols, suggesting that controlling EEB1 expression could be an effective means to regulate the content of these aromatic metabolites in wine. Taken together, the synthesis of ethyl esters can be decreased by deleting one allele of EHT1 and EEB1 in the diploid EC1118 strain, which may modify the ester profile of wine more subtly compared to the complete deletion of target genes.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1995년도 제22회 학술대회
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• pp.1-3
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• 1995

Aspects of the current trend in lubricants and future challenges are discussed. The discussion highlights key enviromnental issues regarding to resource conservation, toxicological consideration and environmental acceptability. Also highlighted are base stocks trends relative to hydroprocessed stocks (HVI, VHQ and XHQ), synthetic base stocks (PAO and organic esters) and biodegradable fluids (vegetable oils and special esters). Equipment severity and lubricant performance quality are briefly described.

• 대한화학회지
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• 제12권2호
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• pp.44-46
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• 1968

몇 가지의 ketosteroid의 carboxymethoxime 및 이들의 methyl ester를 합성하였고 carboxymethoxime의 중화 당량으로부터 ketosteroid의 분자량을 결정할 수 있음을 지적하였다. 또한 이들의 methyl ester는 ketosteroid의 확인인에 이용할 수 있음도 아울러 지적하였다.

• Bulletin of the Korean Chemical Society
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• 제34권6호
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• pp.1927-1929
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• 2013

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.490-493
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• 2003

Enzymatic synthesis of sugar fatty acid esters was investigated in organic solvent using Candida rugosa lipase. To overcome sugars insolubility in organic solvent, sugar absorption procedure was done on a silica gel. The product yield was determined by using ion Chromatography, with various factors such as reaction time, enzyme fatty acid molar ratio, number of carbon in fatty acid.