• 제목/요약/키워드: Acids

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천연 물질을 이용한 이산화탄소 하이드레이트 형성 억제 (Natural Inhibitors for $CO_2$ Hydrate Formation)

  • 사정훈;이보람;박다혜;한건우;전희동;이건홍
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2011년도 추계학술대회 초록집
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    • pp.122.1-122.1
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    • 2011
  • The motivation for this work was the potential of hydrophobic amino acids such as glycine, L-alanine, and L-valine to be applied as thermodynamic hydrate inhibitors (THIs). To confirm their capabilities in inhibiting the formation of gas hydrates, three-phase (liquid-hydrate-vapor) equilibrium conditions for carbon dioxide hydrate formation in the presence of 0.1 to 3.0 mol% amino acid solutions were determined in the range of 273.05 to 281.45 K and 14.1 to 35.2 bar. From quantitative analyses, the inhibiting effects of the amino acids (on a mole concentration basis) decreased in the following order: L-valine > L-alanine > glycine. The application of amino acids as THIs has several potential advantages over conventional methods. First, the environmentally friendly nature of amino acids as compared to conventional inhibitors means that damage to ecological systems and the environment could be minimized. Second, the loss of amino acids in recovery process would be considerably reduced because amino acids are non-volatile. Third, amino acids have great potential as a model system in which to investigate the inhibition mechanism on the molecular level, since the structure and chemical properties of amino acids are well understood.

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Hydrophobicity of Amino Acids in Protein Context

  • Cho, Hanul;Chong, Song-Ho;Ham, Sihyun
    • EDISON SW 활용 경진대회 논문집
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    • 제3회(2014년)
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    • pp.103-113
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    • 2014
  • Hydrophobicity is the key concept to understand the role of water in protein folding, protein self-assembly, and protein-ligand interaction. Conventionally, hydrophobicity of amino acids in a protein has been argued based on hydrophobicity scales determined for individual free amino acids, assuming that those scales are unaltered when amino acids are embedded in a protein. Here, we investigate how the hydrophobicity of constituent amino acids depends on the protein context, in particular, on the total charge and secondary structures of a protein. To this end, we compute and analyze the hydration free energy - free energy change upon hydration quantifying the hydrophobicity - of three short proteins based on the integral-equation theory of liquids. We find that the hydration free energy of charged amino acids is significantly affected by the protein total charge and exhibits contrasting behavior depending on the protein net charge being positive or negative. We also observe that amino acids in the central ${\beta}$-strand sandwiched by ${\beta}$-sheets display more enhanced hydrophobicity than free amino acids, whereas those in the ${\alpha}$-helix do not clearly show such a tendency. Our results provide novel insights into the hydrophobicity of amino acids, and will be valuable for rationalizing and predicting the strength of water-mediated interaction involved in the biological activity of proteins.

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Determination of Fatty Acid Composition and Total Trans Fatty Acids in Meat Products

  • Yilmaz, Ismail;Gecgel, Umit
    • Food Science and Biotechnology
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    • 제18권2호
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    • pp.350-355
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    • 2009
  • In this research, fatty acid composition and trans fatty acids of 22 selected meat products produced by Turkish companies were analyzed by capillary gas liquid chromatography (GLC). Total fat contents of the meat products ranged from 11.60-42.50%. Salami had the lowest fat content 11.60% and sucuk (soudjuk) the highest 42.50%. Major fatty acids were C$_{16:0}$, C$_{18:0}$, trans C$_{18:1}$, cis C$_{18:1}$, and C$_{18:2}$ in the samples. Total unsaturated fatty acid contents have changed from 38.73 to 70.71% of total fatty acids, and sausage had the highest percentage among the samples. The majority of samples contain trans fatty acids and the level ranged from 2.28 to 7.95% of the total fatty acids. The highest amount of total trans fatty acids was determined in kavurma (Cavurmas) (7.95%), and total trans fatty acids of meat products such as pastrami contained more than 5% of the total fatty acids.

관상동맥질환자의 혈청 지방산 조성에 관한 연구 (Serum Fatty Acids in Patients with Angiographically-Documented Coronary Artery Disease)

  • 김수연
    • Journal of Nutrition and Health
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    • 제32권2호
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    • pp.166-174
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    • 1999
  • To study the relation between serum fatty acids and coronary artery disease(CAD), 194 subjects were randomly selected and divided into three groups(control, single vessel disease group(SVD), muliple vessel disease group(MVD)) according to the angiographic results. Total serum levels of fatty acids and serum phospholipid(PL)-fatty acids(FAs)were analysed using gas chromatography and their associations with CAD were examined. Different patterns of total serum fatty acid levels were found in men and women. Levels of most fatty acids of SVD and MVD were significantly lower in men, while those of MVD were significantly higher in women. In terms of PL-FAs in both men and women, the levels of PL-FAs follow the order of control < SVD < MVD and in women, the difference was significant. Various ratio(including ratios denoting the activites of desaturase and elongase) of total serum-and PL-FAs were similar in the three groups. In the relation of serum fatty acids to serum lipid profiles, PUFA & LDL showed a negative correlation, while, SFA & LDL-cholesterol and PUFA and HDL-cholesterol showed positive correlatons. correlations. Systolic blood pressure and alcohol intake levels negatively affected the levels of serum LA, AA, EPA and DHA in the risk factor analysis. These findings are consistent with other evidence indicating that fatty acid compositions are changed in CAD, especially on the concentration base and the change was related to the severity of the disease. Therefore, for the purpose of disease prevention and therapeutic use, balanced intakes of various fatty acids must be seriously considered.

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약용식물(藥用植物)(음나무, 오가피)로부터 생리활성물질(生理活性物質) 검정(檢定) (Identification of Biologically Active Substances from Medicinal Plants)

  • 이인중;김길웅
    • 한국잡초학회지
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    • 제7권3호
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    • pp.289-298
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    • 1987
  • 약용식물(藥用植物)을 대상(對象)으로 생리활성(生理活性)을 지닌 phenolic산(酸)과 지방산(脂肪酸) 및 유기산(有機酸) 등(等)을 조사(調査)한 결과(結果)는 다음과 같다. 음나무와 오가피의 EtOH 추출물(抽出物)은 상치의 발아(發芽)를 강하게 억제(抑制)하는 생리활성물질(生理活性物質)을 함유(含有)하고 있었다. 음나무와 오가피로부터 GLC에 의해 동정(同定)된 phenolic 산(酸)은 protocatechuic 산(酸) 외(外) 11종(種)이었으며 총(總) phenolic 산(酸)의 함량(含量)은 음나무가 1.7971mg/g, 오가피가 0.9567mg/g 이었다. HPLC로 검정(檢定)된 polyphenols은 ncochlorogenic, chlorogenic, scopoletin, rutin, kaempferolglycoside 였으며 chlorogenic 산(酸)의 함량(含量)이 음나무 23.7ppm, 오가피 13.0ppm으로 가장 많았다. 음나무는 지방산(脂肪酸)이 5.26mg/g, 유기산(有機酸)이 27.69mg/g, 오가피는 지방산(脂肪酸)이 3.22mg/g, 유기산(有機酸)이 9.80mg/g 함유(含有)되어 있었으며 음나무가 오가피보다 많은 지방산(脂肪酸)과 유기산(有機酸)을 함유(含有)하고 있었다. 지방산(脂肪酸) 가운데는 linoleic 산(酸)이 전체(全體)의 50% 이상(以上)을, 유기산(有機酸) 가운데는 oxalic 산(酸)이 80% 이상(以上)의 비율(比率)로 함유(含有)되어 있었다.

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건조조건(乾燥條件)에 의(依)한 알로에의 부위별(部位別), 품종별(品種別) 지방산(脂肪酸) 유기산(有機酸) 및 Barbaloin 성분(成分) 연구(硏究) (Fatty and organic acids, and barbaloin in various parts of Aloe species dried at different drying temperatures)

  • 장기운;박종상;장기철;남윤규
    • Applied Biological Chemistry
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    • 제36권4호
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    • pp.244-248
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    • 1993
  • 건조조건에 의한 알로에의 품종별 및 부위별로 지방산 및 유기산과 약효성분인 barbaloin을 추출 분리정량 하였다. 7종의 지방산 및 6종의 유기산과 barbaloin 성분을 확인한 후 각 품종별, 부위별, 건조온도별로 함량을 비교하였다. 7종의 총지방산량으로 볼때 palmitic, eicosanoic acid 함량이 높았으며, Aloe saponaria가 가장 적었다. 6종의 유기산 총량으로는 malic, citric 및 oxalic acid가 다른 유기산보다 많았으며, Aloe sponaria가 함량이 많았고, Aloe arborescence 변종 1은 적었다. $65^{\circ}C$$80^{\circ}C$ 열풍건조시료는 유기산 및 지방산의 함량이 거의 유사하였고, 동결건조한 시료는 열풍건조한 시료보다 함량이 낮았다. Barbaloin의 경우 품종별 함량은 Aloe arborescence 변종 1이 가장 높았으며, 건조조건에 따른 Aloe vera의 barbaloin 성분은 $65^{\circ}C$보다 $80^{\circ}C$의 경우 감소되었고 동결건조가 가장 많은 함량을 나타내었다.

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Influence of organic acids and heat treatment on ginsenoside conversion

  • Jang, Gwi Yeong;Kim, Min Young;Lee, Yoon Jeong;Li, Meishan;Shin, Yu Su;Lee, Junsoo;Jeong, Heon Sang
    • Journal of Ginseng Research
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    • 제42권4호
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    • pp.532-539
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    • 2018
  • Background: Heat treatments are applied to ginseng products in order to improve physiological activities through the conversion of ginsenosides, which are key bioactive components. During heat treatment, organic acids can affect ginsenoside conversion. Therefore, the influence of organic acids during heat treatment should be considered. Methods: Raw ginseng, crude saponin, and ginsenoside $Rb_1$ standard with different organic acids were treated at $130^{\circ}C$, and the chemical components, including ginsenosides and organic acids, were analyzed. Results: The organic acid content in raw ginseng was 5.55%. Organic acids were not detected in crude saponin that was not subjected to heat treatment, whereas organic acids were found in crude saponin subjected to heat treatment. Major ginsenosides ($Rb_1$, Re, and $Rg_1$) in ginseng and crude saponin were converted to minor ginsenosides at $130^{\circ}C$; the ginsenoside $Rb_1$ standard was very stable in the absence of organic acids and was converted into minor ginsenosides in the presence of organic acids at high temperatures. Conclusion: The major factor affecting ginsenoside conversion was organic acids in ginseng. Therefore, the organic acid content as well as ginsenoside content and processing conditions should be considered important factors affecting the quality of ginseng products.

Stability Test and Quantitative and Qualitative Analyses of the Amino Acids in Pharmacopuncture Extracted from Scolopendra subspinipes mutilans

  • Cho, GyeYoon;Han, KyuChul;Yoon, JinYoung
    • 대한약침학회지
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    • 제18권1호
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    • pp.44-55
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    • 2015
  • Objectives: Scolopendra subspinipes mutilans (S. subspinipes mutilans) is known as a traditional medicine and includes various amino acids, peptides and proteins. The amino acids in the pharmacopuncture extracted from S. subspinipes mutilans by using derivatization methods were analyzed quantitatively and qualitatively by using high performance liquid chromatography (HPLC) over a 12 month period to confirm its stability. Methods: Amino acids of pharmacopuncture extracted from S. subspinipes mutilans were derived by using O-phthaldialdehyde (OPA) & 9-fluorenyl methoxy carbonyl chloride (FMOC) reagent and were analyzed using HPLC. The amino acids were detected by using a diode array detector (DAD) and a fluorescence detector (FLD) to compare a mixed amino acid standard (STD) to the pharmacopuncture from centipedes. The stability tests on the pharmacopuncture from centipedes were done using HPLC for three conditions: a room temperature test chamber, an acceleration test chamber, and a cold test chamber. Results: The pharmacopuncture from centipedes was prepared by using the method of the Korean Pharmacopuncture Institute (KPI) and through quantitative analyses was shown to contain 9 amino acids of the 16 amino acids in the mixed amino acid STD. The amounts of the amino acids in the pharmacopuncture from centipedes were 34.37 ppm of aspartate, 123.72 ppm of arginine, 170.63 ppm of alanine, 59.55 ppm of leucine and 57 ppm of lysine. The relative standard deviation (RSD %) results for the pharmacopuncture from centipedes had a maximum value of 14.95% and minimum value of 1.795% on the room temperature test chamber, the acceleration test chamber and the cold test chamber stability tests. Conclusion: Stability tests on and quantitative and qualitative analyses of the amino acids in the pharmacopuncture extracted from centipedes by using derivatization methods were performed by using HPLC. Through research, we hope to determine the relationship between time and the concentrations of the amino acids in the pharmacopuncture extracted from centipedes.

The Metabolites of a Marine Mollusk Mytilus edulis:- Isolation of Taurine and Compositions of Free Fatty Acids and Free Amino acids-

  • Cho, Yong-Jin;Son, Byeng-Wha;Choi, Hong-Dae
    • Natural Product Sciences
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    • 제1권1호
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    • pp.5-9
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    • 1995
  • The metabolites of marine mollusk Mytilus edulis were isolated and characterized, revealing the presence of the rare free fatty acids and proteinogenic amino acids together with a non-proteinogenic free amino acid, taurine. The free fatty acids in this organism were particularly interesting for the presence of both unusual n-6 acid [20:4 (n-6)] and triple bond containing acid (2,5-octadecadiynoic acid). In addition to the proteinogenic amino acids commonly found in proteins, non-proteinogenic free amino acid taurine was isolated and the structure was determined by its physicochemical properties. Recently taurine has been given much interest in the molecular level because of diverse biological activities and the medicinal properties. Furthermore, the result of the analyses of analyses of free amino acids showed that glycine, glutamic acid, serine and alanine, which were considered to be related to the taste of this organism, are predominantly present.

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n-3 지방산과 건강 (n-3 Fatty Acids (EPA, DHA) and Health)

  • 이수환
    • 한국식품위생안전성학회지
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    • 제7권2호
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    • pp.101-105
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    • 1992
  • There is increasing awareness of the devastating socio-economic cost of cardiovascular disease. As a result there have been a lot of extensive researches both on basic mechanisms involved and on the areas of epidemiology and clinical trials. Now it is being generally accepted that dietary n-3 fatty acids abundant in marine products, may reduce the incidence of cadiovascular disease. Fish oil . with its complement of n-3 fatty acids, has been shown the have diverse and sometimes potent actions on cells of the blood and vasculature, which may explain some of its positive effects on vascular disease. However, the appropriate intake of n-3 fatty acids has not been established. This may vary with desired effects, the duration of ingestion, the type of seafood or fish oil and amount of other fatty acids, especially n-6 fatty acid being consumed in the diet. Although the beneficial effects have been extensively studied, little is known about potential adverse effects with excessive intake of n-3 fatty acids. Thus, it is needed to study on the possible unfavorable effects including genetic effects.

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