• Journal of Nutrition and Health
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• v.17 no.1
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• pp.50-59
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• 1984

This study was performed to investigate the placental transfer and the human fetal utilization of amino acids at term of pregnancy. The plasma levels of 23 free amino acids in both the umbilical circulation ( umbilical vein and artery ) and the uterine circulation ( uterine vein and iliac artery ) of 34 pregnant women were measured at delivery by the cesarean section. In the umbilical circulation, 9 amino acids ( alanine, lysine, valine, leucine, arginine, isoleucine, ornithine, cystine, ${\alpha}-aminobutyrate$ ) were significantly higher and 2 amino acids ( glutamate, aspartate ) were significantly lower in the umbilical vein than in the umbilical artery. In the uterine circulation, alanine, tyrosine and methionine were significantly lower in the uterine vein than in the iliac artery. Glutamate was significantly lower in the uterine vein than in the iliac artery. According to these results, the origin of fetal plasma amino acids was discussed in terms of the metabolic conversions which would occur in the Placenta and the fetal utilization of amino acids was estimated.

• BMB Reports
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• v.28 no.1
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• pp.17-20
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• 1995

Thioredoxin reductase is a flavoprotein oxidoreductase catalyzing the reduction of a cystine disulfide in thioredoxin. Thioredoxin, in turn, can reduce disulfide bonds in other proteins and serves as a reducing agent in enzymatic reactions such as those of ribonucleotide reductase and methionine sulfoxide reductase. In this work thioredoxin reductase was found to directly reduce DTNB in the absence of thioredoxin. This new reactivity of E. coli thioredoxin reductase was produced by relatively high concentrations of univalent cations such as $Na^+$, $K^+$, $Li^+$, and ${NH_4}^+$, and it appeared with the oxidation of NADPH. These results indicate that E. coli thioredoxin reductase may be slightly modified by univalent cations, and the modified enzyme directly reacts with DTNB. This DTNB-reducing activity offers a new assay method for E. coli thioredoxin reductase.

• Journal of Nutrition and Health
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• v.16 no.1
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• pp.34-40
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• 1983

Clam, Tapes japonica, has been widely used and occupies an important position in the markets. More than thirty kinds of fermented fish and shellfish are presently available in the markets in korea. This study was attempted to establish the basic data for evaluating the taste compounds of the clam. The free amino acids as taste compounds during the fermentation of the clam, Tapes japonica, were analyzed by an amino acid autoanalyzer. Alanine (17.0%), glycine (15.5%), taurine (13.9%) were high in amount in the fresh clam and then glutamic acid, arginine, tyrosine, asparagine, lysine, threonine, serine and leucine were the next in order. Such amino acids as methionine, phenylalanine, histidine and cystine were low in amounts. The total free amino acid nitrogen in the fresh clam was 45.5% of its extract nitrogen. During the fermentation of the clam, the kinds of the free amino acids were the same with the fresh samples although the amounts were changed. It is believed that glutamic acid, aspartic acid, glycine, alanine, lysine, and leucine may play an important role as the taste compounds in the fermented clam.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.3
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• pp.529-534
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• 1996

Using cystine, ascorbic acid and citric acid, retarding and synergistic effect on the browning reaction of onion juice concentrate was evaluated. Cysteine retarded the browning reaction most effectively followed by citric acid ; on the contrary, ascorbic acid accelerated rather than retarded the reaction at the concentration of 0.1%. The retarding effect of cysteine increased abruptly up to concentration of 0.3% and remained unchanged. Citric acid acted more effectively than ascorbic acid in terms of synergism. The browning reaction of onion juice concentrate exhibited activation energies of 62J/mol with cysteine and citric acid as compared to 73J/mol for control. $Q_{10}$ was determined to be 2.52 and 2.38 for control, 2.2 and 2.09 for treatment in the temperature range of 30~4$0^{\circ}C$ and 40~5$0^{\circ}C$, respectively.

• Korean journal of food and cookery science
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• v.6 no.1
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• pp.27-31
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• 1990

These experiments were carried out to compared with components of AGM and raw beef. The results obtained were summarized as follows: 1) In proximate compositions of raw beef and AGM, water, protein, and fat were 71.21% and 48.47%, 29.35% and 21.85%, 5.36% and 14.95%, respectively. 2) Total amounts of amino acids of AGM were higher than raw beef, and glutamic acid was the highest in both, but methionine was the lowest in AGM, and cystine, in raw beef. 3) In fatty acids composition, unsaturated fatty acids were 90.4%, and linoleic acid (57.63%), among them, was the highest in AGM. But in raw beef, saturated fatty acids were 35.2%, and oleic acid, among them, was the highest content.

• Microbiology and Biotechnology Letters
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• v.24 no.4
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• pp.452-458
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• 1996

A yeast strain TH65 producing a high level of proteinase under alkaline condition was isolated, and identified as Yarrowia lipolytica by morphological, physiological, and biochemical characteristics. In proteinase productivity, glycerol and glucose among tested carbon sources were very effective, and optimum concentration of glucose was 0.5%. Skim milk was found to be most effective nitrogen source in productivity, and its optimum concentration was 0.6%. But, cysteine, cystine and tryptophane decreased the proteinase productivity. Yeast extract was relatively effective at the range of 0.1-0.5%. The yeast showed maximum production of proteinase at 18$\circ$C, pH 9-11, and cultivation time of 36 hours.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.219-219
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• 2003

찹쌀 및 가루를 사용하여 담금한 고추장(시험구 A: 찹쌀가루, 시험구 B: 찹쌀, 시험구 C: 찹쌀 및 가루의 혼용)의 화학성분, 효소력 및 texture를 측정한 결과는 다음과 같다. 수분, 조단백, 조지방, 적정산도, 무기성분, alcohol의 함량 및 PH는 시험구간에 차이가 없었다. 이미노태 질소함량과 산성 pretense 및 당화 amylase 활성은 A구가 높았고 환원당은 Brn가 경시적으로 높았다. Ca, Cu, K, Mn, Mg, P, Fe의 무기성분이 각 시험구에서 검출되었고 이중 K의 함량이 가장 높았으며 Cu, Mn, Fe는 극히 미량이었다. Aspartic acid, glutamic acid, cystine, arginia proline 등의 유리아미노산이 60일 숙성 고추장에서 양적으로 많이 검출되었고 histidine, valine의 함량은 적었으며, 유리아미노산의 총량은 A구 16.49, B구 13.68, C 구 15.84mg/g으로서 A 구가 가장 많았고 B 구의 고추장이 가장 적었다. texture를 측정한 결과 견고성과 부착성은 담금 직후에는 A구가, 숙성 후기에는 B 구가 높았으며 응집성, 탄력성은 A 구가 높았고 B 구가 낮았다.

• YAKHAK HOEJI
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• v.47 no.4
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• pp.218-223
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• 2003

Effect of taurine treatment on metabolism of glutathione (GSH) was studied in adult male ICR mice. An acute injection of taurine (250 mg/kg, ip) resulted in a significant decline of hepatic GSH level at t = 6 hr, but plasma GSH level was not altered. The activity of GSH-related enzyme in liver, such as GSH peroxidase, GSSG reductase, GSH S-transferases, ${\gamma}$-glutamylcysteine synthetase or ${\gamma}$-glutamyltranspeptidase, was not affected by taurine at t = 2.5 or 6 hr. Plasma cysteine and cystine levels were elevated rapidly following taurine treatment. Hepatic cysteine level was decreased by taurine, reaching a level approximately 70％ of control at t = 4 and 6 hr. In conclusion, the results indicate that an acute dose of taurine decreases hepatic GSH level by reducing the availability of cysteine, an essential substrate for synthesis of this tripeptide in liver. It is also suggested that taurine may decrease the cysteine uptake by competing with this S-amino acid for a non-specific amino acid transporter.

• Proceedings of the Korean Fiber Society Conference
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• 1996.10a
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• pp.478-483
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• 1996

다관능성 에폭사이드 PPE(Polyglycerol Polyglycidyl Ether)를 양모섬유에 처리하였을 때 부가반응의 특성을 고찰하였다. 에폭사이드 PPE에 의한 부가반응이 촉매작용을 하는 NaSCN 존재하에서 이관능성 EGDE보다 높은 부가율을 얻을 수 있었다. 에폭사이드 부가반응은 고온에서 반응이 잘 일어나며 에폭사이드 처리욕의 pH는 반응 초기 급격히 상승했다가 이후 점차 초기 값까지 안정화된다. 처리한 양모섬유를 FTIR의 KBr-pellet법과 ATR법에 의해 분석하여 absorbance ratio를 비교하였을 때 부가반응은 표면으로의 그라프트 반응이 우세함을 알 수 있었으며 이러한 결과는 SEM 관측을 통하여 확인할 수 있었다. Performic acid/Ammonia solubility를 에폭사이드 처리 양모섬유에 적용하여 용해도 변화를 보았을 때 부가된 양이 많을수록 용해도 값이 감소하며 특히 15.6%를 중심으로 용해도 변화가 둔화되었다. 아미노산 분석으로 에폭사이드가 반응한 아미노산이 cystine임을 알 수 있었으며 단백질 사슬간에 가교반응이 이루어졌음을 확인할 수 있었다.

• Journal of Nutrition and Health
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• v.3 no.2
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• pp.113-117
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• 1970

1) It was found that the polished rice is short of Iysine, methionine, cystine, and tryptophan among the essential amino acids, and that it shows no significant variations with regard to its pattern of geographical region. 2) Comparing in the contents of essential amino acids in the cereals, such as polished barley, wheat, great millet, and soy bean, the soy bean is found to be better than the polished rice, while the others to be either poorer or similar than the polished rice. 3) The aminal experiments observed with the mixed diet revealed that the most ideal composition of the mixed diet is the one composed of 70% polished rice, 20% polished barley, and 10% soy bean.