• 한국산학기술학회논문지
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• 제11권4호
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• pp.1367-1372
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• 2010

유연한 곁사슬을 가지고 있는 copoly(ether-ether-ester)가 중축합반응에 의하여 합성되었다. 테트라클로로에탄 중에서 측정된 중합체의 고유점성도 값은 0.42~0.78 dl/g을 나타내었다. 합성된 고분자의 구조는 $^1H$-NMR과 FT-IR에 의하여 조사되었으며, 열적성질과 액정성은 DSC, TGA, POM, XRD에 의하여 측정되었다. 조사된 결과에 의하면 합성된 공중합체들은 모두 단독중합체보다 낮은 용융전이온도를 나타내었으며, 공중합체 내의 비페닐렌 단위의 함량이 60 mol %이상일 때 네마틱액정상이 관찰되었으며, 합성된 중합체의 액정성은 비페닐렌 함량에 의존하였다.

• Journal of Mechanical Science and Technology
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• 제19권10호
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• pp.1902-1909
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• 2005

A process for production of ethyl ester for use as biodiesel has been studied. The sodium hydroxide catalyzed transesterification of soybean oil with ethanol was carried out at different molar ratio of alcohol to oil, reaction temperature and catalyst amount for a constant agitation in two hours of reaction time. Central composite design and response surface methodology were used to determine optimum condition for producing biodiesel. It was found that ethanol to oil ratio and catalyst concentration have a positive influence on ester conversion as well as interaction effects between the three factors considered. An empirical model obtained was able to predict conversion as a function of ethanol to oil molar ratio, reaction temperature and catalyst concentration adequately. Optimum condition for soybean ethyl ester production was found to be moderate ethanol to oil ratio (10.5: 1), mild temperature range ($70^{\circ}C$) and high catalyst concentrations ($1.0\%$wt), with corresponding ester conversion of $93.0\%$.

• 생약학회지
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• 제26권2호
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• pp.130-138
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• 1995

Phytochemical study on the aerial parts of Solanum lyratum (Solanaceae) was carried out. On the basis of phytochemical and spectroscopic evidences, compound I was identified as mixtures of hexadecanoic acid methyl ester, 2,6,10,15-tetramethyl heptadecane, tricosane, tetracosane, pentacosane, docosanoic acid methyl ester, docosane, tricosanoic acid methyl ester, 8-hexyl pentadecane, tetracosanoic acid methyl ester, pentatriacontane, hexatriacontane, eicosane, hexacosane, hentriacontane and stigmasta-5,23-dien $3-{\beta}-ol$, and compound II, III, IV and V were identified as hexacosanoic acid methyl ester, ${\beta}-sitosterol-{\beta}-{_D}-glucoside$, $3-O-{\alpha}-{_L}-rhamnopyranosyl-(1->2)-{\beta}-{_D}-glucuronopyranosyl$ diosgenin and $3-O-{\alpha}-{_L}-rhamnopyranosyl-(1->6)-{\beta}-{_D}-glucopyranosyl$ quercetin (rutin), respectively. Rutin was identified as one of the active principles having antioxidative effect from S. lyratum.

• Journal of Genetic Medicine
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• 제9권1호
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• pp.38-41
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• 2012

A 32-year-old female patient and her sister show high levels of high density lipoprotein (HDL) cholesterol in regular health checkups, since female patient was 11 years old. The patient's serum total cholesterol was 285 mg/dL and HDL cholesterol was 113 mg/dL. Her sister's total cholesterol was 240 mg/dL and the HDL cholesterol measured to be 90 mg/dL. Lipoprotein pattern and cholesteryl ester transfer activity gene analysis were examined in these patients. We found c.1321+1G>A (IVS14+1G/A) hetero mutation in cholesteryl ester transfer protein (CETP) genes. Generally, CETP mediates transfer and exchange of triglycerides and cholesteryl ester between plasma lipoproteins. Also we investigated a key role of HDL-CE and Apo A-1 metabolism. Patients with low levels of CETP have increased serum HDL levels. We hereby report two Korean cases of CETP deficiency in a family. Brief literature review ensues with the cases.

• 한국식품영양과학회지
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• 제26권6호
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• pp.1033-1038
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• 1997

Antioxidant effect of several antioxidative components on the high purity $\alpha$-linolenic acid(HALA; ALA, 78.1%) ethyl ester concentrated from perilla oil were investigated by measuring weight-gains and peroxide value(POV) during storage at 5$0^{\circ}C$, 23$^{\circ}C$ and 4$^{\circ}C$. Amounts of antioxidant components were 0.2g/kg HALA ethyl ester for sesamin, sesangolin and butylated hydroxytolune(BHT), and 0.1g/kg for sesamol and 100g/kg for ether extracts from perilla seed. The oxidative stability of HALA ethyl ester was particularly increased by adding sesamol, ether extracts and BHT, but sesamin and sesangolin scarcely showed an antioxidant effect. POV on the HALA ethyl ester added sesamol and ether extract was less than 15.0meq/kg by 9 weeks of storage at 23$^{\circ}C$. However, in the case of low temperature storage at 4$^{\circ}C$, all the samples estimated showed less than 7.0meq/kg in POV by 5 months. Consequently, sesamol and ether extracts were recognized as available antioxidant components on the HALA ethyl ester from perilla oil.

• 한국식품영양학회지
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• 제36권5호
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• pp.354-359
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• 2023

A mono-type glycerine fatty acid ester compound was chemically synthesized using medium-chain fatty acids with antibacterial activity, and the physicochemical quality and antibacterial activity of the synthesized glycerine medium-chain fatty acid ester compound were measured. At a reaction molar ratio of MCT(medium chain triglyceride) to glycerine of 1:2.5, 48.15% mono ester was produced. The physicochemical analysis of the synthesized glycerine fatty acid ester compound showed an acid content of 0.38~0.60%, which tended to increase slightly as the glycerine molar ratio increased. The saponification value decreased as the synthesized molar ratio of glycerine increased from 218 to 284. The number of bacteria was measured to confirm the degree of antibacterial activity of glycerine medium-chain fatty acid esters against food poisoning bacteria, Bacillus cereus and Salmonella typhi. The number of bacteria significantly decreased as the MCT:glycerine molar ratio increased. In particular, the antibacterial effect between the treatment groups was the highest when at an MCT:glycerine molar ratio of 1:2.5.

• 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.

• Natural Product Sciences
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• 제6권2호
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• pp.53-55
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• 2000

In the course of continous work for the discovery of anti-thrombotic constituents from tubers of Gastrodia elata, citric acid 1,5-dimethyl ester was isolated from ethylacetate soluble fraction prepared from the methanol extract. The structure of the compound was determined by the spectroscopic data. The anti-thrombotic effect of this compound was observed with prolonging the bleeding time in thrombin-induced thrombosis model of mice.

• Bulletin of the Korean Chemical Society
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• 제26권2호
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• pp.292-296
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• 2005

Physical and chemical properties of thexylboronic acid and its derivatives such as thexylboroxine and ethylene glycol or diethanolamine thexylboronic ester have been studied. Thexylboronic acid can be extracted from an organic solution with an aqueous sodium hydroxide solution as an “te”complex. It is readily converted into thexylboroxine in the presence of anhydrous magnesium sulfate in pentane. It reacts with simple alcohols only slowly; however, it reacts readily with excess diethanolamine in the presence of anhydrous magnesium sulfate to give the corresponding ester.

• Archives of Pharmacal Research
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• 제14권1호
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• pp.48-51
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• 1991

Amides from amino acid ester and nalidixic acid were synthesized. The solubility characteristics and partition coefficient of the compounds were studied. The hydrolysis of the compounds was studied in the simulated gastric fluid and simulated intestinal fluid. Some compounds showed better antibacterial activity than nalidixic acid.