• 통합자연과학논문집
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• 제9권1호
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• pp.28-34
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• 2016

A number of chiral selectors have been developed and applied for enantiomer separation of a variety of chiral compounds. Among these chiral selectors are chiral crown ethers, a class of synthetic host polyether molecules that bind protonated chiral primary amines with high selectivity and affinity. In this paper, two important chiral crown ethers as chiral selectors of bis-(1,1'-binaphthyl)-22-crown-6 and (18-crown-6)-2,3,11,12-tetracarboxylic acid (18-C-6-TA) are focused. They have been widely used to resolve the enantiomers of chiral compounds containing a primary amino moiety using chiral stationary phases (CSPs) or chiral selectors by high-performance liquid chromatography (HPLC), capillary electrophoresis (CE) and so on in chirotechnology. Also, it was described that the commercially available covalent type HPLC CSPs derived from (+)- and (-)-18-C-6-TA have been developed and successfully applied for the resolution of various primary amino compounds including amino acids.

• 한국식품과학회지
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• 제28권3호
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• pp.433-439
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• 1996

Major components affecting nonenzymatic browning in stored ginger paste were investigated using five synthetic model solutions.　The model systems were stored at $40^{\circ}C$ for 30 days and analyzed for browning, in addition the contents of sugars, organic acids, ascorbic acids, amino acids and gingerols were determined. Among the chemical components, fructose, asparagine and ascorbic acid were the main contributors to the browning development of ginger paste, while gingerol compounds were browning inhibitors.

• Bulletin of the Korean Chemical Society
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• 제8권3호
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• pp.189-192
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• 1987

The syntheses of mercaptotetrazoles and cephalothin analogs are described. Their in vitro potency was established. The compounds exhibited high antibacterial activity against Gram-positive bacteria and moderate activity against Gram-negative bacteria.

• 한국수산과학회지
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• 제17권1호
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• pp.33-39
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• 1984

우리 나라 중요 담수어의 정미성분을 밝힐 목적으로 전보에 이어서 천연산 뱀장어배육중의 유리아미노산, 핵산관련물질, 유기염기, 유기산, 당류 및 무기질을 분석하였다. 또한 이 분석치를 기초로 하여 표준시약을 가지고 합성엑스분을 조제하여 천연엑스분과 맛을 비교하였으며, omission test를 실시하여 각성분들이 맛에 미치는 영향을 조사하였다. 유리아미노산의 함량은 lysine 함량이 가장 많아 42.4mg/100g으로서 전체 유리아미노산의 $25\%$를 차지하였으며, 다음으로 glycine, arginine, alanine, histidine 및 proline 둥이 함량이 많았다. 핵산관련물질은 IMP함량이 78.7 mg/100 g으로서 월등히 많았으며, 그 외의 성분은 비교적 함량이 적었다. 유기염기에서는 creatinine이 252.5mg/100g으로서 가장 많았고, betaine은 23.9mg/100g이었으며, TMA 및 TMAO는 1mg/100g미만으로 극미량이었다. 유기산의 경우는 부티르산, 발레르산, 숙신산 및 프로피온산의 함량이 많았고 옥살산, 푸마르산, 말레산, 타르타르산 및 시트르산은 흔적량에 불과하였다. 당류의 함량은 포도당과 inositol이 $1{\sim}2$mg/100g이고 그 외 ribose, arabinose, fructose는 흔적량으로 나타났다. 무기염류의 함량을 보면 $K^+$ 및 $PO_{4}^{3-}$이 각각 170.0mg/100g, 278.6mg/100g으로서 월등히 많았고, $Na^+$ 및 $Cl^-$의 함량은 모두 31.0mg/100g으로 함량이 적었으며 $Ca^{2+}$ 및 $Mg^{2+}$은 4.0mg/100g이하로 그 함량이 아주 적었다. 관능검사 결과, 중요한 맛성분으로는 glycine, serine, glutamic acid, IMP, $Na^+,\;K^+,\;Cl^-$ 및 $PO_{4}^{3-}$이었으며, lysine, alanine, isoleucine, aspartic acid 및 creatinine 등이 맛의 조화에 기여하고 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제11권5호
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• pp.550-558
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• 1998

The experiment was conducted to evaluate CM (Cell Mass from Lysine Fermentation), which is used to produce synthetic lysine in industry, as an alternative protein source in broiler diets. Three different production conditions were employed to produce CMs (CM I, II, III). Treatments were control, CM I -1 (1 % of CM in the diet), CM I -3 (3% of CM in the diet), CM I -5 (5% of CM in the diet), CM II (3% of CM in the diet), and CM III (3% of CM in the diet). It was found that CM products were all high in crude protein content and especially high in lysine and methionine contents, while very low in minerals. For the starter period, all CM groups showed better weight gain, chicks fed CM I -1 diets were especially high in weight gain (p < 0.05). CM groups consumed 14.4 to 18.0% more feed than chicks fed control diets (p < 0.05). The best FCR was found in CM I -1 groups (p < 0.05), but as CM level was increased, FCR was also increased. For the finisher period, weight gain was similar through all treatments. Through whole experimental period, weight gain and feed intake were higher in all CM groups than control group (p < 0.05), however, as CM level was increased, FCR was also increased. Generally chicks fed CM diets showed higher utilizabilities of gross energy, dry matter, crude protein and crude fat. The best nutrients utilizability was obtained in CM I -1 group, and the worst was found in the control group. During the finisher period, the utilizabilities of crude protein, crude ash and phosphorus were not affected by the dietary treatments. Amino acids utilizability was not significantly affected by the treatments except CM I -5 group. In all amino acids tested, chicks did not show the big difference in utilizabilities. Only in the CM I -5 group, amino acids utilizability was significantly lower than control group. However, among CM I groups, the mean value of the amino acids utilizability was decreased as the level of CM inclusion in the diet was increased. During the finisher period, similar trend was found in amino acids utilizability.

• 한국해양학회지
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• 제30권4호
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• pp.341-354
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• 1995

동해의 8개 정점에서 해수 및 추출된 용존 유기물의 형광특성과 아미노산 조성이 연구되었다. C-18 Sep-Pak cartridge에 의해 추출된 시료는 3차원 형광특성 분석에 따 라 생거대물질과 지구거대물질로 구분되었다. 전 조사 정점을 통하여 생거대물질(ex : 280 nm/em : 330 nm)은 표층이 높고 수온약층 아래에서 점차 감소하는 것으로 나타났 으며 이는 표층혼합층의 생물 활동에서 기인된 분해가능한 생거대물질이 수온약층 부 근 및 저층에서 활발한 미생물 분해과정에 의해 감소하는 것으로 사료된다. 한편 이와 는 역상관계를 보이는 지구거대물질 (ex : 330 nm/em : 430 nm)은 표층은 낮고 수온약 층 아래에서 증가하였는데 이는 표층에서 생성된 생거대물질 및 입자유기체가 생물 분 해 후 재축합 과정을 거쳐 난분해성의 지구거대물질로 전환된 것으로 사료된다. HPLC 를 이용하여 해수와 추출된 유존유기물의 아미노산 조성을 분석하였다. 분석결과 Glycine, serine 그리고 alanine등이 우점하였으며, 전체 농도의 50% 이상을 차지하는 것으로 조사되었다. 해수중의 용존 자유아미노산 농도는 표층이 0.7∼1.8um 범위로 저 층 0.2∼0.4um보다 높게 측정되었다. 추출된 유기물중 alanine의 D/L racemice ratio 측정결과 저층보다 표층이 상대적으로 낮은 값을 보였으며 이는 표층의 생거대물질이 연령이 젊고 재순환이 빠르며 생물 분해가능성이 큰 물질임을 시사하고 있다.

• 한국식품영양학회지
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• 제36권6호
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• pp.572-580
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• 2023

Hypertension is characterized by excessive renin-angiotensin system activity, leading to blood vessel constriction. Several synthetic compounds have been developed to inhibit renin and angiotensin-converting enzyme (ACE). These drugs often have adverse side effects, driving the exploration of plant protein-derived peptides as alternative or supplementary treatments. This study assessed the phenolic compound and amino acid content and the antioxidant and antihypertensive activity of 5 South Korean staple crops. Sorghum had the highest phenolic compound content and exhibited the highest antioxidant activity. Millet grains, particularly finger millet (38.86%), showed higher antihypertensive activity than red beans (14.42%) and sorghum (17.16%). Finger millet was found to contain a large proportion of branched-chain, aromatic, and sulfur-containing amino acids, which are associated with ACE inhibition. In particular, cysteine content was positively correlated with ACE inhibition in the crops tested (r=0.696, p<0.01). This study confirmed that the amino acid composition was more correlated with the antihypertensive activity of grains than the phenolic compound content. Finger millet mainly contained amino acids, which have higher ACE inhibitory activity, resulting in the strongest antihypertensive activity. These findings underscore the antihypertensive potential of select crops as plant-based food ingredients, offering insight into their biological functions.

• 생약학회지
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• 제7권1호
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• pp.3-13
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• 1976

The hitherto existing gap in the field of chromatographic methods has been filled by the direct coupling of a suitable oven (TAS-oven) with TLC. The sample to be examined is heated either isothermally or linearly within the temperature gradient of $50{\sim}450^{\circ}C$. The volatile and/or thermolytically evolved substances are fractionated on the TLC-layer and subsequently chromatographed under standard conditions. Transport mechanisms from the sample to the TLC-layer, applications of the TAS-procedure and further developments are discussed. Thermofractography, developed from the TAS-procedure, is demonstrated on different groups of natural substances such as alkaloids, amino acids, nucleic acids. nucleosides, nucleotides, triglycerides and other lipids, pyrone glycosides and aglycon. Experimental work and results on the thermolysis of macromolecular natural and synthetic substances, natural polyphenols, tanning agents and leather and the possibilities of differentiating various lignins, carbohydrate and synthetic polymers are reported. Further, it is shown that classical reactions in the microgram range, e.g. zinc dust distillation, sulphur-and selenium dehydrogenation and catalytic dehydrogenation, can be coupled directly with TLC. Also described is a method which allows to investigate the gaseous compounds evolved during thermofractography in the range of up to $450^{\circ}C$. Thermal procedures coupled with TLC open up the following new possibilities for chemical microanalysis: fractionated separation of distillable and sublimable components, fractionated thermolysis and carrying out of thermal reactions in the ultra micro range.

• 대한화학회지
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• 제46권4호
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• pp.309-317
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• 2002

형광분광법에 의하여 주성분 회귀분석(principal component regression, PCR)과 부분 최소자승법(Partial least squares, PLS)을 이용하여 아미노산(Tryptophan and Tyrosine)을 동시에 정량하는 방법에 대하여 연구하였다. 아미노산 혼합물의 형광 스펙트럼은 들뜸파장을257nm로 고정하여 측정하였다. 두 가지 아미노산이 서로 다른 농도로 혼합되어 있는 32개의 시료용액을 280nm∼500nm 범위에서 스펙트럼들을 얻었고 이를 이용하여 PCR과 PLS회귀모델을 얻었다. 두 가지 아미노산이 서로 다른 농도로 포함된 6개의 외부검정용 시료들의 스펙트럼들을 이용해서 회귀모델의 적합성을 검정하기 위하여 외부검정용 시료의 농도를 계산하였다. 계산된 농도를 이용하여 relative standard error of prediction($RSEP_a$)를 얻었고 같은 방법으로 overall relative standard error of prediction($RSEP_m$) 도 구하였다

• BMB Reports
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• 제44권10호
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• pp.669-673
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• 2011

Human methionine sulfoxide reductase B3A (hMsrB3A) is an endoplasmic reticulum (ER) reductase that catalyzes the stereospecific reduction of methionine-R-sulfoxide to methionine in proteins. In this work, we identified an antimicrobial peptide from hMsrB3A protein. The N-terminal ER-targeting signal peptide (amino acids 1-31) conferred an antimicrobial effect in Escherichia coli cells. Sequence and structural analyses showed that the overall positively charged ER signal peptide had an Argand Pro-rich region and a potential hydrophobic ${\alpha}$-helical segment that contains 4 cysteine residues. The potential ${\alpha}$-helical region was essential for the antimicrobial activity within E. coli cells. A synthetic peptide, comprised of 2-26 amino acids of the signal peptide, was effective at killing Gram-negative E. coli, Klebsiella pneumoniae, and Salmonella paratyphi, but had no bactericidal activity against Gram-positive Staphylococcus aureus.