• Title/Summary/Keyword: organic acids.

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Changes in Taste Components of Marsh Calm Soup as Affected by Boiling Time (재첩국 제조시 가열시간에 따른 맛성분의 변화)

  • Chun, Soon-Sil;Suh, Jae-Soo;Oh, Chan
    • The Korean Journal of Food And Nutrition
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    • v.13 no.6
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    • pp.529-533
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    • 2000
  • The marsh calm soup was prepared with 2 volumes of boiling water and heated for 0, 5, 10, 30, 60 and 120 minutes. As the boiling time prolonged, water content decreased gradually, while protein content increased. Free amino acid content was the highest with 30 minutes of boiling showing 103.1 mg/100g, and decrease showly thereafter. Among the free amino acids, alanine was the most abundant followed by proline, glutamic acid and glycine. Degree of protein hydrolysis increased as boiling prolonged. In the non-volatile organic acids, succinic acid was the highest(137.08 mg/100g with 30 minutes of boiling), followed by oxalic acid, magic acid and lactic acid. The optimum boiling time for marsh calm soup was evaluated to be 30 minutes.

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Seasonal Variations of Taste Components in Warty Sea Squirt(Styela clava) (계절에 따른 미더덕의 정미성분 조성 변화에 관한 연구)

  • 이강호;김민기;홍병일;정병천;이동호;박천수
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.24 no.2
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    • pp.274-279
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    • 1995
  • Seasonal variation of the taste components such as free amino acids, nucleotides, quarternary ammonium bases, and guanidino compounds in warty sea squirt(S. clava) were determined bimonthly from April to October for its food quality contributed in Korean seafood dishes. Fifty to sixty two percentage of the extractable nitrogen was free amino acids, and mainely it composed of taurine, proline, glutamic acid, glycine and glycinebetaine. Among the various taste component, betaine's level was somewhat higher(11~15%) and nucleotides related compounds also followed(5~8%). Most of nitrogenous compounds in the extractives reached to a maximum value in June and AMP content was relatively higher than the other nucleotides. The major organic acids were composed of succinic acid, malic acid, lactic acid and pyroglutaric acid in S. clava. The result of omission test suggested that the taste of S. clava is mainly attributed to free amino acids, betaines, nucleotides and non-volatile organic acid in order.

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Nutritional Characteristics of Juvenile Black Rockfish Sebastes schlegeli Fed a Diet of Fig Leaf Extract (무화과 잎 추출물 첨가 사료를 급이한 조피볼락(Sebastes schlegeli)치어의 영양학적 특성)

  • Hwang, Jae-Ho;Lee, Si-Woo;Rha, Sung-Ju;Han, Kyeong-Ho;Kim, Seon-Jae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.45 no.6
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    • pp.570-578
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    • 2012
  • The present study investigated the effect of diets supplemented with different levels (0, 1, 3, and 5 %) of fig leaf ethanol extract (FLEE) on the nutritional composition of black rockfish Sebastes schlegeli. Fish ($10.05{\pm}0.44g$) were fed to apparent satiation twice daily for 8 weeks. Adding FLEE decreased crude lipid levels and increased crude protein and ash. Among the three organic acids in the whole body of black rockfish, lactic acid was predominant, followed by citric acid and oxalic acid. Five free sugars were found in all groups. Fucose and glucose were the dominant free sugars in the FLEE-added group. The abundant fatty acids in the FLEE-added group were C16:0, C18:1-cis (n9), and C22:6n-3. The major amino acids in the samples were glutamic acid, aspartic acid, glycine, leucine, alanine, lysine, and arginine. The abundant free amino acids in the FLEE-added group were taurine, glutamic acid, alanine, leucine, and arginine.

Characterization of Itraconazole Semisolid Dosage Forms Prepared by Hot Melt Technique

  • Shim, Sang-Young;Ji, Chang-Won;Sah, Hong-Kee;Park, Eun-Seok;Lee, Beom-Jin
    • Archives of Pharmacal Research
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    • v.29 no.11
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    • pp.1055-1060
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    • 2006
  • The objective of this study was to formulate itraconazole semisolid dosage forms and characterize their physicochemical properties. Itraconazole and excipients such as polysorbate 80, fatty acids, fatty alcohols, oils and organic acids were melted at $160^{\circ}C$. The fused solution was then cooled immediately at $-10^{\circ}C$ to make wax-like semisolid preparations. Their physicochemical attributes were first characterized using differential scanning calorimetry, Fourier transform infrared spectroscopy and nuclear magnetic resonance spectrometry. The solubility of itraconazole in semisolid preparations and their dispersability in the simulated gastric fluid were also determined. Our semisolid preparations did not show any distinct endothermic peak of a crystalline form of itraconazole around $160-163^{\circ}C$. This suggested that it was changed into amorphous one, when it was formulated into semisolid preparations. In addition, the distinctive functional peaks and chemical shifts of itraconazole were well retained after processing into semisolid preparations. It could be inferred from the data that itraconazole was stable during incorporation into semisolid preparations by the hot melt technique. In particular, itraconazole semisolid preparations composed of polysorbate 80, fatty acids and organic acids showed good solubility and dissolution when dispersed in an aqueous medium. It was anticipated that the semisolid dosage forms would be industrially applicable to improving the bioavailability of poorly water-soluble drugs.

Elicitation에 의한 인삼 모상근의 성장 및 이차 대사산물 생산

  • Jeong, Gwi-Taek;Lee, Gwang-Yeon;Hwang, Baek;U, Je-Chang;Park, Don-Hui
    • 한국생물공학회:학술대회논문집
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    • 2001.11a
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    • pp.487-488
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    • 2001
  • The effects of biotic elicitors, organic acids, and environmental changes on the growth of Panex. ginseng hairy roots were investigated in the shaking flask culture. Among the organic acid tested, gluconic acid was found to be the most efficient in the hairy roots growth. And citric and succinic acid were facilitated the growth of hairy roots.

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Wet Etching Behaviors of Transparent Conducting Ga-Doped Zinc Oxide Thin Film by Organic Acid Solutions

  • Lee, Dong-Kyoon;Lee, Seung-Jung;Bang, Jung-Sik;Yang, Hee-Sun
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.831-833
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    • 2008
  • 150 nm thick Ga-doped ZnO thin film, which was deposited by a sputtering process, was wet-chemically etched by using various organic acids such as oxalic, citric and formic acid. Wet etch parameters including etchant concentration and temperature are investigated for each etchant, and their effects on the etch rate and the feature of edge line are compared.

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The Taste Components of Ordinary Korean Soy sauce (한국재래식(韓國在來式) 간장의 맛 성분(成分)에 관한 연구(硏究))

  • Kim, Jong-Kyu;Kim, Chang-Sik
    • Applied Biological Chemistry
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    • v.23 no.2
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    • pp.89-105
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    • 1980
  • Soysauce was made in the salt concentrations of 22.0% and 28.5%, and the changing aspects in nucleotides and their related compounds, free amino acids, free sugars and non-volatile amines which are related to the taste components during the fermentation process with a view to examining the taste components in the ordinary Korean soysauce were studied. And then artificial soysauce was prepared by applying the values derived from the analysis and measurement, and its sensory evaluation was performed. As the result of the sensory evaluation of artificial soysauce prepared according to the value of components analyzed from soysauce which had been fermented for fourty days in the salt concentration of 22.0%, it has been found that artificial soysauce was similar in taste to ordinary Korean soysauce. So, the following facts have been found: glutamic acid and aspartic acid have MSG-like taste, and IMP has a synergistic effect with these acids, which play great roles in ordinary Korean soysauce; both free sugars such as galactose and amino acids such as glycine, alanine and lysine have sweet taste; both amines such as tyramine and histamine, and amino acids such as valine, leucine, isoleucine, and phenylalanine have bitter taste; these components, combined with saline taste of salt and sour taste of organic acids, are assumed to form the unique taste in the ordinary Korean soysauce.

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Synthesis of α-Ketobutyrolactones and γ-Hydroxy-α-Keto Acids

  • Kang, Han-Young;Ji, Yu-Mi;Yu, Yeon-Kwon;Yu, Ji-Yeon;Lee, Young-Hoon;Lee, Sang-Joon
    • Bulletin of the Korean Chemical Society
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    • v.24 no.12
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    • pp.1819-1826
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    • 2003
  • In connection with the studies for developing new enzymes that could be useful in organic synthesis, practical preparation of racemic and enantiopure forms of ${\gamma}$-hydroxy-${\alpha}$-keto acids has been successfully achieved. For racemic form of ${\gamma}$-hydroxy-${\alpha}$-keto acids, indium-mediated allylation of aldehydes with 2-(bromomethyl)acrylic acid has been employed as a key step. Oxidative cleavage of the thus formed 2-methylenebutyrolactones provided the desired ${\alpha}$-ketobutyrolactones. Enzymatic resolution of the ${\gamma}$-hydroxy-${\alpha}$-methylene esters provided the desired${\gamma}$-hydroxy-${\alpha}$-methylene acids which were successfully converted to ${\gamma}$-hydroxy-${\alpha}$-ketobutyrolactones in optically pure forms.

Effects of Humic Acids on Growth of Herbaceous Plants in Soil Contaminated with High Concentration of Petroleum Hydrocarbons and Heavy Metals (고농도 유류와 중금속으로 복합 오염된 토양에서 식물성장에 미치는 부식산의 영향)

  • Kim, Ki-Seob;Sung, Ki-June
    • Journal of Soil and Groundwater Environment
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    • v.16 no.1
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    • pp.51-61
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    • 2011
  • Germination tests were conducted to determine the practical concentration levels at which plants can reproduce naturally during the phytoremediation of soils contaminated with a high concentration of petroleum hydrocarbons and heavy metals. The effects of humic acids on plant growth and soil physicochemical properties were also investigated. The results show that phytoremediation can be applied in soils contaminated by multiple contaminants at the former soil contamination potential level of Korean soil quality standards considering successful natural reproduction. It was observed that germination rates of Helianthus annuus and Festuca arundinacea were high after all treatments, and transplantation was more appropriate for Phragmites communis in phytoremediation. Humic acids had a positive effect on the growth of both aboveground and belowground biomass of herbaceous plants. Growth inhibition by multiple contaminants is more severe in the case of aboveground biomass. Germination and growth tests suggest that Helianthus annuus is a suitable phytoremediation plant for soils contaminated with a high concentration of petroleum hydrocarbons and heavy metals. The addition of humic acids also caused changes in the physicochemical properties of contaminated soils. An increase in the carbon and nitrogen content due to the addition of humic acids and a correlation between cation exchange capacity(CEC) and the organic matter content were observed.

Physicochemical Characteristics of Corn Silk (옥수수 수염의 이화학적 특성과 변이)

  • Kim, Sun-Lim;Park, Cheol-Ho;Kim, E-Hun;Hur, Han-Sun;Son, Young-Koo
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.45 no.6
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    • pp.392-399
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    • 2000
  • This study was carried out to investigate the physicochemical characteristics of corn silks. Pollination of corn silks was finished within three days after silking, and elongation of open pollinated corn silks was stopped, but unpollinated silks elongated until eight days after silking. Moisture contents of corn silks were about 92-94% at silking stage, but continuously decreased. these were about 70-75% at 30 days after silking. Chlorophyll b was higher than chlorophyll a in corn silks, and chlorophyll a/b ratios of four hybrids were high in this order : silage > sweet > super sweet > waxy corn. Free sugars in corn silks were mainly fructose, glucose and maltose. Their composition rate was 55% of glucose, 42% of fructose and 4% of maltose. Water soluble solid (Brix %) contents of unpollinated corn silks were ranged from 13.7 to 16.8 Brix % and pollinated corn silks were from 12.6 to 13.7 Brix %. Phytic, oxalic, malic. shikimic, glutaric and acetic acid were detected on corn silks. Phytic, oxalic and glutaric acid were considered as a major organic acids in corn silks. Amino acids in corn silks were high in this order : waxy > silage > sweet >sweet corn. Serine, glycine and thereoine were contained more than 10%, and five amino acids such as aspartic, glutaric, arginine, alanine and proline were ranged about 5 to 8%. Methionine and cystine, amino acids containing sulfur were contained only small quantity as about 2.1% and 1.3%, respectively. Acetaldehyde, ethanol, acetone, DMS, isobutylaldehyde, cis-3-hexanol, 3-hexe-1-ol, acetate, trans-2-hexanol and pentanol were detected as the volatile components in corn silks, but acetaldehyde and DMS were major volitiles in silage corn silks, and acetaldehyde, ethanol and DMS were major volitiles in waxy corn silks. The length of corn silks was a positively correlated with organic acids (r=${0.556}^*$), and a negatively correlated with amino acids (r=${-0.514}^*$), respectively. Free sugars were positively correlated with all characteristics tested and significantly correlated with organic acid (r=TEX>${0.703}^{**}$), and flavonoids (r=TEX>${0.544}^*$). Chlorophyll was significantly correlated with flavonoid contents (r=TEX>${0.523}^*$). For this reason chlorophyll was evaluated as an indirect selection character for the high flavonoid containing varieties.

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