• 대한가정학회지
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• 제19권1호
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• pp.25-31
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• 1981

The changes of various nitrogenfractions and free amino acid composition were investigated at various growing stages. The results are summarized as follows 1) Total nitrogen, water soluble protein nitrogen, and true protein nitrogen were decreased with growth. 2) Free amino acid increased with sprout-growth. the content of free amino acid were about 74.4%(combined Ser, Asp, Arg, Val) after 4 day sprout. It is belived that serine, aspartic acid, arginine and valine play an important role as taste compounds in mungbean sprout. 3) 16kinds of amino acid, including essential amino acids in human nutrition except tryptophan and cystin were quantified.

• Asian-Australasian Journal of Animal Sciences
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• 제15권10호
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• pp.1507-1516
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• 2002

Meat and bone meal is a valuable protein and mineral source in diets of production animals and contributes to the protein, energy and mineral component of diets. The aim of the present study was to more accurately characterise the apparent ileal amino acid digestibility of meat and bone meals produced in New Zealand and evaluate routine in vitro assays used in practise to measure meat and bone meal quality. A total of 94 commercial meat and bone meals from 25 New Zealand rendering plants over a two and a half year period were analysed for proximates, gross energy, gross amino acid content (incl. hydroxyproline, hydroxylysine and lanthionine), apparent ileal amino acid digestibility, pepsin nitrogen digestibility, protein solubility and bone content. The mean crude protein content of the 94 meat and bone meal samples was 56.8% with a range of >35% units and a coefficient of variation of 9.8%. The mean crude fat and ash content were 10.0 and 28.4% respectively. These latter components showed a large range (16 and 43%, respectively) with coefficients of variation above 22%. Amino acid digestibility between samples was highly variable with lysine and sulphur amino acids digestibility ranging between 45.8-89.0 and 38.2-85.5%, respectively. Pearson correlation coefficients are presented between crude protein content and individual gross amino acids, crude protein content and individual digestible amino acid content, and pepsin N digestibility and individual digestible amino acid content. There was a significant relationship between the digestible amino acid nitrogen content and the crude protein content while pepsin nitrogen digestibility was not correlated to ileal amino acid nitrogen digestibility (r=-0.06). Meat meals with a high protein content had relatively low hydroxyproline and hydroxylysine levels something that was attributed to the levels of collagen from bone. The data indicated that lanthionine (formed upon heat treatment of cysteine with a hydroprotein) is not a good indicator of the heat treatment employed to meat and bone meals. Step-wise multiple regression equations to predict the apparent digestible content of amino acids from rapid in vitro assays are presented. The most selected variables included ash and crude fat content. In general the equations derived for the essential amino acids had a higher degrees of fit (R2) compared to the non-essential amino acids. The R2 for the essential amino acids ranged from 0.43 for histidine and 0.68 for leucine. These equations provide a means of more rapidly estimating the apparent ileal digestible amino acid content (protein quality) of meat and bone meal using standard analyses.

• Asian-Australasian Journal of Animal Sciences
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• 제12권8호
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• pp.1298-1309
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• 1999

The nutritional value of protein varies between feedstuffs. It is possible to feed animals using crystalline amino acids as a sole nitrogen source, but in practice only some limiting amino acids are added to the diet. In order to use feedstuffs efficiently, it is important to determine exact amino acid requirements. Reported values differ widely because the requirements are affected by various factors. In this report, therefore, the factors affecting amino acid requirements are reviewed as follows: 1) availability of dietary amino acids, conversion factors of nitrogen to protein, interaction of amino acids, and strain, sex and age of animals; 2) amino acid requirements for maximum performance and maintenance, usefulness of non-essential amino acids; 3) plasma amino acid concentration as a parameter to determine amino acid requirements; and 4) nitrogen excretion to reduce environmental pollution. These factors should be considered, it is to improve the dietary efficiency, which is to reduce excess nitrogen excretion for environmental pollution.

• Asian-Australasian Journal of Animal Sciences
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• 제33권5호
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• pp.679-695
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• 2020

Evaluating amino acid requirements, specifically threonine requirements, in horses will enable better feed formulation and result in economic production, improved animal health, and reduced environmental pollution. However, the current knowledge of protein and amino acid requirements in horses is still limited. Because horses have a unique digestive system and consume a variety of feed ingredients, their protein digestibility may be affected than other species by different feed composition, and thus amino acid requirements are susceptible to vary between situations. Therefore, a careful evaluation of amino acid requirements with a proper method is needed for various conditions. This review will also provide comprehensive information that needs to be considered when designing an amino acid requirement study in horses.

• 한국식품영양과학회지
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• 제22권5호
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• pp.586-591
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• 1993

지리산 싸리의 유리 아미노산, 총 아미노산 조성과 총 지방산 조성을 규명하기 위한 gas chromatography와 HPLC를 사용하여 분리 정량한 결과는 다음과 같다. 조지방 함량은 11.13%이고, 조단백질 함량은 5.18%로 조성되어 있다. 유리 아미노산의 총 함량은 433.14mg/100g으로 조성되어 있으며, 유리 아미노산 중에서 필수 아미노산의 총 함량은 94.84mg/100g으로 21.90%를 차지하고 있다. 총 아미노산의 함량은 3159.85mg/100g으로 조성되어 있으며, 총 아미노산중에서 필수 아미노산의 함량은 1068.18mg/100g으로 35.80%를 차지하고 있다. 총 지방산 조성은 $C_{18\;:\;2}$가 45.05%로 제일 많이 함유되어 있고, $C_{18\;:\;3}=18.71%,\;C_{19}=14.70%,C_{18\;:\;1}=6.81%,\;C_{16}=4.35%,\;C_{16\;:\;1}=1.59%$순으로 함유되고 있고, 탄소소 홀수 지방산이 14.70% 함유되어 있으며, 불포화 지방산이 72.44%이고, 필수 지방산은 63.76%를 차지하고 있는 결과로 볼 때 유지자원 및 사료의 자원으로 가치가 있다고 판단된다.

• Applied Biological Chemistry
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• 제15권1호
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• pp.35-40
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• 1972

The contents of free amino acids in deembryod brown rice of two varieties were investigated by amino acid autoanalizer in relation to specific gravity grade. The analytical methods of free amino acid were also discussed. 1) The lower the specific gravity of the unhulled rice the higher the content of total free amino acids in the deembryod brown rice, and the similar trend appears to hold on each amino acids. 2) Main free amino acids were serine+asparagine, glutamic acid, aspartic acid, alanine and valine, and maximum values of them were 7.3, 5.1, 4.0, 3.4, 0.9mg/100g rice, respectively. They consist about 85% of total free amino acids in most cases. 3) The contents of soluble nitrogen and free amino acids appear to be lower in high protein variety (IR 667) than in low protein variety (Jinhung). The percentage of free amino acid nitrogen to soluble nitrogen, however, appears to be higher in high protein variety (IR 667). 4) Alanine was much lower than aspartic acid in IR 667 having Indica blood while alanine appears to be higher than aspartic acid in Jinhung (Japonica rice) suggesting varietal difference in amino acid metabolism. 5) Threonine peak was overlaped with glutamine, and serine was with asparagine in this study.

• Journal of Plant Biology
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• 제7권1호
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• pp.1-4
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• 1964

A comparative study of free amino acid content in healthy and virus diseased tobacco leaves was carried out by author throughout the gorwing season from June to November of 1963. The methods of qualitative analysis of free amino acids applied in this experiment is followed by Moore and Stein. 1,2 Free amino acids determined in this experiment are shown in Fig. Ⅰ, Ⅱ and Table Ⅰ. As the figure and the table are shown, four more amino acids such as a spartic acid, glutamic acid, tyrosine and phenylalanine are detected in the healthy leaves; these four additional amino acids in the healthy leaves are conspicuous. More quantities of asparagine and alanine are detected in the diseased leaves than the healthy leaves and more quantities of tryptophan is detected in the healthy leaves. It is presumed that such amino acids as tyrosine and phenyllanine are decreased by the incooperation of free amino acid to TMV protein in the process of the process of the leaf protein metabolism which is caused by TMV-RNA trapping action in the diseased leaf protoplasm. It is thought that the decrease of asparagine and the increase of asparic acid in the healthy leaves are the results of in incooperaton of NH2, produced by the protein dissimilation in the diseased leaves, to aspartic acid; it's reaction is caused by the respiration of the diseased leaves accelerated by TMV attack. It is presumed, consequently, that the check of the diseased tobacco leave growth is influenced by the reduction of such amino acids as tryptophane and glutamic acid, which reduction may be due to the abnormal protein metabolism and the action of certain enzyme caused by TMV attack on host protoplast.

• Journal of Nutrition and Health
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• 제28권10호
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• pp.976-985
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• 1995

Changes in free amino acid concentrations is blood and various tissues were evaluated in cats adapted to the low-protein diet(20% protein, LPD) or the high-protein diet(60% protein, HPD) for 5 weeks. Cumulative body weigth gain for the 5 week period was 463$\pm$43g, and -128$\pm$40g for cats fed HPD and LPD, respectively. Feeding HPD significantly increased the size of liver and kidney. Cats adapted to HPD for 5 weeks have significantly elevated plasma concrntrations of essential amino acids (branched-chain amino acides, threonine, trytophan, phenylalanine and methoionine), whereas plasma levels of non-essential amino acids(alanine, asparagine, glycine, glutamine and serine) were significantly reduced in animals adapted to HPD(p<0.01, or p<0.001) compared to the values for the cats fed LPD. Changes in free amino acid concentratioks in whole blood induced by the variations in dietary level of protein closely reflect the pattern seen in plasma. Amino acids such as branched-chain amino acids, proline and threonine were most difficult to maintain homeostasis and consistantly elevated in lever, kidney, skeletal muscle and brain, as well as in blood of cats adapted to HPD(p<0.01 or p<0.001). All of the free amino acids in jejunum, excluding taurine and ornithine, were significantly elevated in animals adapted to HPD, most probably due to the rapid absorption of large amount of amino acids across the epithelium of small intestine.

• 운동영양학회지
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• 제15권4호
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• pp.153-161
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• 2011

The maintenance of skeletal muscle mass is very important for the prevention of life style-related diseases and the improvement of quality of life. It is well-known that resistance exercise and nutrition (especially amino acids) are the most effective interventions for maintaining skeletal muscle mass. It has been reported that many molecules are involved in the regulation of protein synthesis in response to resistance exercise and nutrition. Understanding the molecular mechanisms regulating muscle protein synthesis is crucial for the development of appropriate interventions. The role of intracellular signaling pathways through the mammalian target of rapamycin (mTOR), a serine/threonine protein kinase in the regulation of muscle protein synthesis, has been extensively investigated for these years. Control of protein synthesis by mTOR is mediated through phosphorylation of downstream targets that modulate translation initiation and elongation step. In contrast, upstream mediators regulating mTOR and protein synthesis in response to resistance exercise and amino acid still needed to be determined. In this brief review, we discuss the current progress of intracellular mechanisms for exercise- and amino acid-induced activation of mTOR pathways and protein synthesis in skeletal muscle.

• 한국정보과학회논문지:소프트웨어및응용
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• 제37권1호
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• pp.74-79
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• 2010

단백질의 아미노산 조성은 생물정보학의 여러 문제를 해결하기 위한 기초적인 정보로 자주 활용된다. 본 논문에서는 아미노산간의 진화적인 연관성을 정의한 BLOSUM 행렬에서 유도한 유사도 함수를 사용하여 아미노산 조성을 결정한다. 이러한 방법은 생물학적인 연관성이 있는 단백질 서열일수록 비슷한 아미노산 조성을 갖도록 한다. 또한 단백질의 구조와 기능에 중요한 역할을 하는 위치-특이적인 아미노산의 분포를 추정하기 위해서 레이더나 음성 신호의 스펙트럼 분석에 사용되는 개념인 시간-종속 분석, 시간 해상도와 주파수 해상도의 개념을 적용하였다. 제안한 방법을 단백질의 세포내 위치예측에 적용하여 기존의 아미노산 조성 추정 방법을 사용하는 것보다 크게 향상된 성능을 보임을 확인하였다.