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Isolation and Identification of Volatile Compounds from Red Wine Manufactured with Vitis vinifera grapes (Vitis vinifera 적포도주 휘발성분의 분리 및 동정)

  • 이용수;최진상;심기환
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.22 no.2
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    • pp.196-201
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    • 1993
  • In order to investigate some chemical components, higher alcohols, ethyl acetate and volatile compounds of Vitis vinifera red wines were analyzed by HPLC, GC and GC-MS. During the process of ripening for the content of wine and acids were much changed, particurally the content of tartaric acid was decreased largely. Content of total phenolics and phenol flavonoid in wines which manufactured with Malbec varieties as 470mg/L and 245mg/L respectively, was higher than those in Cabernet sauvignon (310mg/L, 135mg/L) and Cabernet franc (425mg/L, 125mg/L) wines, and nonflavonoid was higher in Cabernet franc wine(300mg/L) than in others. Content of acetaldehyde was higher in Malbec wine (33mg/L) than in Cabernet sauvignon (26mg/L) and Cabernet franc (28mg/L) wines. Amount of methyl alcohol, propanol and isoamyl alcohol were higher in Cabernet sauvignon wine than in others, and isobutanol was more in Malbec wine(64mg/L), ethyl acetate was more in Cabernet franc wine as 35mg/L than in Malbec(28mg/L) and in Cabernet sauvignon (23mg/L) wines. Volatile compounds were isolated about 87~91 varieties from concentrates of three red wines by GC, and thirty-five compounds including terpine-4-ol were identified by GC-MS.

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Synthesis and Characterization of New Polyaza Non-macrocyclic and Macrocyclic Nickel(II) Complexes Containing One 1,3-Diazacyclohexane Ring

  • Lee, Yun-Taek;Jang, Bo Woo;Kang, Shin-Geol
    • Bulletin of the Korean Chemical Society
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    • v.34 no.7
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    • pp.2125-2130
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    • 2013
  • A new nickel(II) complex $[NiL^1]^{2+}$ ($L^1$ = 1-(2-aminoethyl)-3-(N-{2-aminoethyl}aminomethyl-1,3-diazacyclohexane) containing one 1,3-diazacyclohexane ring has been prepared selectively by the metal-template condensation of formaldehyde with N-(2-aminoethyl)-1,3-propanediamine and ethylenediamine at room temperature. The complex reacts with nitroethane and formaldehyde to yield the pentaaza macrocyclic complex $[NiL^2]^{2+}$ ($L^2$ = 8-methyl-8-nitro-1,3,6,10,13-pentaazabicyclo[13.3.1]heptadecane) bearing one C-$NO_2$ pendant arm. The reduction of $[NiL^2]^{2+}$ by using Zn/HCl produces $[NiL^3(H_2O)]^{2+}$ ($L^3$ = 8-amino-8-methyl-1,3,6,10,13-pentaazabicyclo[13.3.1]heptadecane) bearing one coordinated C-$NH_2$ pendant arm that is readily protonated in acid solutions. The hexaaza macrocyclic complex $[NiL^4]^{2+}$ ($L^4$ = 8-phenylmethyl-8-nitro-1,3,6,8,10,13-hexaazabicyclo[13.3.1]heptadecane) bearing one N-$CH_2C_6H_5$ pendant arm has also been prepared by the reaction of $[NiL^1]^{2+}$ with benzylamine and formaldehyde. The nickel(II) complexes of $L^1$, $L^2$, and $L^4$ have square-planar coordination geometry in the solid states and in nitromethane. However, they exist as equilibrium mixtures of the square-planar $[NiL]^{2+}$ (L = $L^1$, $L^2$, or $L^4$) and octahedral $[NiL(S)_2]^{2+}$ species in various coordinating solvents (S); the proportion of the octahedral species $[NiL(S)_2]^{2+}$ is strongly influenced by the ligand structure and the nature of the solvent. Synthesis, spectra, and chemical properties of the nickel(II) complexes of $L^1-L^4$ are described.

Synthesis and Characterization of Poly(L-lactic acid-co-glycine-L-lactic acid) and Poly - ( L-1actic acid-co-gl ycine-L-methyl 1actic acid) (생체분해성 고분자의 합성 및 물성에 관한 연구(II) -Poly (L-lactic acid-co-glycine-L-lactic acid) 와 Poly- (L-lactic acid-co-glycine-L-methyl lactic acid))

  • Sung, Yong-Kiel;Song, Dae-Kyung;Park, Kyung-Hee
    • Journal of Biomedical Engineering Research
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    • v.9 no.2
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    • pp.225-232
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    • 1988
  • Poly (L- lactic acid-co-glycine-L-lactic acid) and Poly (L-lactic acid-co-glycine-L- methyl lactic acid ) have been prepared by ring opening polymerization. The monomer 6, 6-dimethyl morpho-line-2, 5-dione was synthesized by the bromoisobutylation of 2-bromoisobutyryl bromide with glycin e. L-lactide, 6-methyl morpholine-2, 5-diode. and 6, 6-dimethyl morpholine-2, 5-diode have been used as starting materials for polydepsipeptides. The synthesized monomers and copolymers have been identified by NMR and FT-lR spa- ctrophotometer. The thermal propert ies and glass transition temperature(Tg) of the copolymers have been measured by differential scanning calorimetry. The Tg values of poly(L-lactic acid co-glycine-L-lactic acid) system are increased from $53^{\circ}C\; to\; 107^{\circ}C$ with increasing the mole fraction of 6-methyl morpholine-2, 5-diode. And the Tg values of poly(L-lactic acid co-glycine-L-methyl lactic acid) system are increased from $53^{\circ}C\;to\;138^{\circ}C$ with increasing the mole fraction of 6. 6-dimethyl morpholine-2, 5-diode The thermal stability of poly (L-lactic acid-co-glycine-L-methyl lactic acid) is slightly greta text than that of poly(L-lactic acid-co-glycine-L-lactic acid) due to the methyl group.

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Study on Myocardial Protective Effect of L-arginine (L-Arginine의 흰쥐 적출심근보호 효과에 관한 연구)

  • 이인성;이헌재
    • Journal of Chest Surgery
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    • v.29 no.10
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    • pp.1076-1080
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    • 1996
  • The results about the myocardial protection of recta of the nitric oxide precursor L-arginine upon reperrusion injury after ischemia are diverse. These diversities may be model dependent. Experiments were designed and performed to investigate myocardial protection effects according to the concentration of L-arginine. The Isolated rat hearts were subjected in a 30 minutes oi normothermic ischemia and reperfused for 30 minutes with reperfusate containing 0, 1, 2, 3, 4 moil L-arginine. After 30 minutes of reperfusion, group with 1 and 2 mM/L L-arginine showed a trend of better recovery in left ventricular systolic function(left ventricular developed pressure, positive maximum dpfdt), diastolic function(negative maximum dpfdt) and coronary flow compared to control group(reperfusate no L-arginine). Recovery was impaired with a higher concentration, and at 4 moil L-arginine r covery was worse than control(p (0, 05). These results suggest that optimal concentration of L-arginine Is Important or the recovery of myocardial and endothelial function after ischemia and reperfusion.

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Auxin-like Effect of the Antibiotic Carbenicillin on Organogenesis of Leaf Discs of Tobacco (Nicotiana tabacum L. cv. BY-4) (담배 (Nicotiana tabacum L. cv. BY-4) 잎절편의 기관분화에 대한 항생제 carbenicillin의 auxin 유사효과)

  • 배창휴;양덕춘;이효연
    • Korean Journal of Plant Tissue Culture
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    • v.27 no.6
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    • pp.469-474
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    • 2000
  • Effect of the antibiotic carbenicillin on callus and shoot formation from the leaf disc culture of tobacco (Nicotiana tabacum L. cv. BY-4) was examined. The number of shoot induced from the leaf explants was decreased as the amount of carbenicillin increased from 250 mg/L to 2,000 mg/L on MS medium containing 0.5 mg/L of BAP or kinetin. In addition, calli formation from the leaf explants was increased by the treatment of 250 mg/L ∼ 500 mg/L carbenicillin with or without 0.5 mg/L of 2,4-D or NAA. However, the fresh weight of 4-week-cultured explants was decreased with increasing carbenicillin from 250 mg/L to 2,000 mg/L on MS medium containing 0.5 mg/L of 2,4-D or NAA. These results indicate that carbenicillin has an auxin-like effect, such as promoting callus formation and inhibiting shoot induction. It leads to the conclusion that the auxin-like property should be taken into account for the production of transgenic plants via Agrobacterium-mediated transformation.

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Influences of Proteolytic Ability of Lactic Acid Bacteria on Acid Production and Precipitates Occurrence in Liquid Yogurt Preparation (액상발효유 제조시 유산균 Starter의 단백질 분해능이 산생성 및 침전발생에 미치는 영향)

  • 소명환
    • Microbiology and Biotechnology Letters
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    • v.12 no.4
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    • pp.285-291
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    • 1984
  • In making liquid yoghurt, the influences of proteolytic ability of lactic acid bacteria on acid production and on protein stability were investigated. L. bulgaricus CH-2, L. helviticus IAM 1042 and L. jugurti 3048 showed a comparatively high proteolytic activity in milk, while L. casei YIT 9018 did not show any marked proteolysis. Starter organisms having high proteolytic ability showed more rapid growth and acid production than those having low ability in milk. The most active proteolysis occurred during logarithmic growth phase of yogurt organisms, and most of the proteolysis took place in the first 24-48 hrs of incubation. Highly proteolysed yogurts made by L. bulgaricus CH-2, L. jugurti 3048, L. helviticus IAM 1042, L. acidophilus L-54 and L. casei 3012 had low protein solubility at pH 3.5 and had much protein precipitates during storage of product, but those having little protein hydrolysates made by L. casei YIT 9018 or artificial acidification showed no precipitation during keeping.

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Effects of Sucrose Concentration on the Production of hGM-CSF in Transgenic Plant Cell Suspension Culture (형질전환된 식물세포에서 Sucrose 농도가 hGM-CSF 생산에 및 미치는 영향)

  • Lee, Jin-Ok;Shim, Doo-Hee;Joo, Chi-Un;Kim, Dong-Il;Lee, Dong-Geun;Lee, Jae-Hwa
    • Journal of Plant Biotechnology
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    • v.31 no.2
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    • pp.163-167
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    • 2004
  • The effects of sucrose concentration on the secretion of hGM-CSF, total protein and protease into the medium were investigated in transgenic tobacco cells. The dry cell weight (11.22 g/L), hGM-CSF (181.53 $\mu\textrm{g}$/L) and total protein (66.8 mg/L) were detected as highest at 30 g/L sucrose and protease activity (2660 U/L) was highest at 120 g/L sucrose after 5-day culture. However after 10-day culture, the maximum dry cell weight (28.36 g/L) was found at 60 g/L sucrose while the maximum hGM-CSF (95 $\mu\textrm{g}$/L) was appeared at 150 g/L sucrose. The total protein and protease activity was secreted as 52.28mg/L and 3430 U/L, respectively in the same culture.

An Efficient Implementation of Hybrid $l^1/l^2$ Norm IRLS Method as a Robust Inversion (강인한 역산으로서의 하이브리드 $l^1/l^2$ norm IRLS 방법의 효율적 구현기법)

  • Ji, Jun
    • Geophysics and Geophysical Exploration
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    • v.10 no.2
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    • pp.124-130
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    • 2007
  • Least squares ($l^2$ norm) solutions of seismic inversion tend to be very sensitive to data points with large errors. The $l^1$ norm minimization gives more robust solutions, but usually with higher computational cost. Iteratively reweighted least squares (IRLS) method gives efficient approximate solutions of these $l^1$ norm problems. I propose an efficient implementation of the IRLS method for a hybrid $l^1/l^2$ minimization problem that behaves as $l^2$ norm fit for small residual and $l^1$ norm fit for large residuals. The proposed algorithm shows more robust characteristics to the decision of the threshold value than the l1 norm IRLS inversion does with respect to the threshold value to avoid singularity.

High Density Cell Culture of Bifidobacterium by Optimization of Medium Composition and Culture Conditions. (배지조성 및 배양환경 최적화에 의한 Bifidobacterium의 고농도 배양)

  • 송수한;김택범;지근억;오훈일;오덕근
    • Microbiology and Biotechnology Letters
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    • v.30 no.1
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    • pp.63-67
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    • 2002
  • Bifidobacterium strain was isolated from the feces of brast fed infants. The isolated strain was identified as Bifidobacterium longum by 16S rRNA sequence analysis and named as Bifidobacterium SH2. The MRS medium was modified to obtain high density cells of Bifidobacterium SH2. The optimal medium was determined to be 50 g/L lactose, 10 g/L beef extract, 10 g/L peptone, 5 g/L yeast extract, 7 g/L sodium acetate, 2 g/L ammonium citrate, 2 g/L disodium phosphate,1 g/L tween 80, 0.2 g/L MnSO$_4$ and 0.5 g/L L-cysteine. The pH and temperature were optimized as 5.0 and $37^{\circ}C$, respectively. Through out the optimization of medium composition and culture conditions, the dry cell weight and viable cell count were 2.5 times and 1.8 times higer than those in MRS medium, respectively.

Radon Concentration in Groundwater of Korea (전국 규모로 본 국내 지하수의 라돈 함량)

  • Cho, Byong-Wook
    • The Journal of Engineering Geology
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    • v.28 no.4
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    • pp.661-672
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    • 2018
  • Radon concentration was measured in a total of 5,453 groundwater samples from wells across Korea. The radon concentrations showed the values ranging from 0.1 Bq/L to 7,218.7 Bq/L, with a median of 48.8 Bq/L which is lower than those of other countries having similar geological conditions. The distribution of radon concentrations was lognormal. The median value is high in the granite areas (63.5-105.1 Bq/L) while it is low in the sedimentary rocks and Cheju volcanic area (16.0-20.3 Bq/L). When grouping the groundwater with well depth, the median radon value is high in weathering and/or upper bedrock zone (61.4 Bq/L) while it is low in alluvium and/or weathering zone (28.5 Bq/L). About 17.7% of the total samples exceeded 148 Bq/L of USEPA guideline value. The exceeding radon ratio more than 148 Bq/L in groundwater is highest in Jurassic granite area, however, the exceeding radon rates more than 300 Bq/L and 500 Bq/L are highest in CGRA area.