• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.630-631
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• 2000

지방산과 당의 transesterification에 의하여 제조되는 당에스테르를 분리정제하는 방법으로 크로마토그라피방법을 조사하였다. 당에스테르제조에 사용되고 있는 각종 지방산(oleic, stearic, palmitic acid)과 당에스테르의 크로마토그라피 용출특성을 이동상의 유속과 온도, 그리고 주입량을 변화시켜 관찰하였다. 본 실험에서 사용한 column은 Silica 계통의$C_{18}$ column($3.9{\times}300mm$) 이었으며 본 실험에서 조사한 지방산과 당에스테르의 혼합물은 모두 높은 해상도로 분리되는 것을 관찰하였다.

• 생명과학회지
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• 제9권6호
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• pp.737-742
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• 1999

천일염에서 분리된 고호염성균인 Haloarual sp. EH-1으로부터 PHA를 생산하여 PHA의 구조 및 성질 등을 검토하였다. 그 결과는 다음과 같다. PHA를 GC chromatogram, IR 및 300MHz H-NMR로 분석한 결과 Haloarcnly sp. EH-1으로부터 추출된 PHA는 3-hydroxybutyric acid와 3-hydroxyvaleric acid 와 3-hydroxyvaleric acid의 중합체인 PBB/HV로 추정되었으며, thermal property는 $152.46^{\circ}C.$ 점도는 1.25dl/g 그리고 분사량은 $1.44 X 10^5$이었다.

• 한국식품위생안전성학회지
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• 제9권4호
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• pp.185-189
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• 1994

This study was to investigate time-dependent degradation process under various pH condition for organophosphorus(org-p) insecticides, namely Demeton-s-methyl, diazinon, Parathion, Phenthoate, and EPN in several waters. They were analysed by GC-FTD according to standard methods for the examination of water and wastewater. In pH=4, diazinon showed disappearance after 14 days in chromatogram. In pH=11, org-p insecticides were almost degradable after 7 days. In this condition, effect of pH on degradation process was greater than of light. In pH=7, org-p insecticides persisted residues after 112 days except Demeton-s-methyl. In BOD5 120, 250 ppm and domestic water, org-p insecticides showed also rapid degradation process.

• Biotechnology and Bioprocess Engineering:BBE
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• 제6권1호
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• pp.31-36
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• 2001

Optimal operation in chromatography is needed to save operation time and the solvent used in multiple chromatographic runs. To this end, many simulation studies of chromatography process have been performed. The relationship between the distribution coefficient and the ionic strength is important in gradient elution ion chromatography. Experimental runs and computer simulations were carried out under linear gradient elution condition in order to compare the experiments and the simulation. Experiments were performed with formic acid under isocratic conditions to determine the simulation equation parameters. Computer simulation was based on three equations which related distribution with ionic strength as follows; K=${\alpha}$I(sup)-${\beta}$, K=A+BI+Cl$^2$and K=y(sub)0+A$_1$$.$e(sup)(-I/m$_1$). The effects of gradient slope on the chromatograms are discussed, and good agreement between the experimental and the simulated results is shown.

• 분석과학
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• 제5권3호
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• pp.339-343
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• 1992

HPLC-UV방법을 이용하여 밀전분 지방질의 주성분인 LPC를 정량하기 위해 HRW 밀전분 지방질로부터 순수한 LPC를 분리하여 LPC의 표준곡선을 작성하였다. 밀 품종별 LPC에서 대한 HPLC peak responses는 시료간 큰 차이를 보여주지 않아 HRW 밀전분 지방질로부터 만든 LPC의 HPLC-UV 표준곡선은 밀전분 지방질에 함유되어 있는 LPC의 함량을 신속하고 정확하게 정량하는 데 이용할 수 있음을 보여 주었다.

• Journal of Microbiology and Biotechnology
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• 제3권4호
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• pp.270-276
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• 1993

We characterized the character impact compounds of flavors of the fermented Korean soy sauce manufactured with both the traditional and the improved Meju made with different strains. The whole flavor samples were obtained by extracting each volatile flavor phase from both the traditional and the improved soy sauce. To get more detailed information, each whole volatile flavor was further fractionated into the basic, acidic, phenolic and neutral fractions. Each separated peak from the whole and fractionated flavor samples on gas chromatogram was identified by GC/MS and Kovat s retention index, and likewise the aroma of each peak was investigated by a sniffing test with the exercised panel. We were able to identify 15 groups of ingredients with the characteristic soy sauce aroma from the soy sauce made with the traditional Meju and 6 groups from the soy sauce manufactured with the improved Meju made with Aspergillus oryzae. The character impact compounds the two soy sauces were different from each other.

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 2005년도 제36차 추계 학술발표대회
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• pp.329-333
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• 2005

ACE inhibition activity of peptides was measured after 2 months of storage at $4^{\circ}C$ under condition of pH 6.0, 6.5, 7.0, 7.5, 8.0. and the ACE inhibitory activity were changed only slightly. After 2 months of chilled storage ($4^{\circ}C$), no dramatic change and significance was found. This indicates that acidic, neutral, weak alkali conditions did not affect ACE inhibitory activity of those peptides. Among peptide 1134, 1152, and 1155, peptides from thermolysin + protease A hydrolysates, inhibition activity of peptide 1134 and 1152 was decreased significantly at $60^{\circ}C$, however, they showed stable inhibition activity from $70^{\circ}C$ to $100^{\circ}C$ (P<0.001). Also, chromatogram of peptide 1134, 1152, and 1155 was shown that retention time of peptide of $60^{\circ}C$ was not correspond to the retention time of the rest of peptides. This indicated that temperature may change the inhibitory activity and profile of peptides.

• Journal of Ginseng Research
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• 제10권2호
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• pp.187-192
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• 1986

Activity of endogenous growth regulator in 4th year Panax ginseng root was investigated by second leaf sheath test of rice seedling and paper chromatogram of a acidic fraction of methanol extract before (March 28) and after (May 9) emergence of root bud, at the late season (Sept.4) and after leaf fall (November 11). GA$_3$ and ABA were used as reference. According to paper and high performance liquid chromatography of samples and authentic growth regulators the presence of insole acetic acid (IAA), gibberellic acid (GA$_3$) and abscisic acid (cis and trans ABA) was confirmed. These three regulators appeared to consist of major system though the existence of other regulators could not be ruled out. IAA activity seemed little changed through out the seasons. GA activity decreased in the later stages while ABA activity increased.

• Elastomers and Composites
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• 제51권1호
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• pp.63-67
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• 2016

Poly(ethylene-co-vinyl acetate) (EVA) was pyrolyzed to eliminate acetic acid of VA unit using off-line pyrolysis, and the deacetylated EVA was analyzed infrared spectroscopy (IR) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). EVA film for deacetylation was prepared by solution casting on aluminum foil and it was pyrolyzed at low temperature of $300^{\circ}C$ in the off-line pyrolysis apparatus. After deacetylation, carbon-carbon double bond (C=C) was formed by 1,2-elimination of the VA unit in the EVA backbone. Most of C=C bonds were trans-1,4-unit and 1,2-unit was also observed. Presence of the 1,2-unit in deacetylated EVA indicates that terminal or branch VA units exist in the raw EVA. Py-GC/MS chromatogram of deacetylated EVA displayed much smaller acetic acid and much more abundant other pyrolysis products than that of raw EVA, which means that the pyrolysis efficiency and separation condition were improved.

• The Korean Journal of Physiology
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• 제19권2호
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• pp.215-225
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• 1985

흰쥐의 태아에서 ACTH의 분비양상을 알아보기 위하여, 태아의 제태일수에 따라 혈장 및 뇌하수체 전엽에서 여러 분자형태의 ACTH를 방사면역측정법으로 측정하였다. 태아의 혈장 ACTH농도는 제태 19일에서 가장 높았으며 그후 계속 감소하여 출생후 1주에서 가장 낮은 값을 보였다. 출생 1주후부터 ACTH농도는 다시 증가하기 시작하여 출생후 21일에서는 거의 성체의 값에 도달하였다. 측정된 ACTH는 chromatogram상에서 항상 3가지 peak가 나타났다. 즉 'big'형 ('big' ACTH, $MW\approx44,000$), 'intermediate'형 ('intermediate' ACTH, $MW\approx13,000$)및 'little'형 ('little' ACTH, $MW\approx4,500$)으로 구분되었다. 임신말기 (제태기간 17일에서 21일 사이)에서 태아 혈장의 ACTH는 'little'형의 비율이 증가한 반면 'big'형의 비율은 감소하였다. 그러나 뇌하수체 전엽에서 분비된 ACTH는 3가지 형이 같은 비율이었다. 뇌하수체 전엽에서 분리한 'big'형의 ACTH를 시침관내에서 trypsin을 처리한 결과 'intermediate'형과 little'형이 출현하였다. 이 결과로 미루어 태아 흰쥐의 뇌하수체에서 분비된 ACTH가 순환도증 다른 형으로 전환될 수 있음이 시사된다.