• Asian-Australasian Journal of Animal Sciences
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• v.12 no.8
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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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• v.33 no.5
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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.

• Journal of Microbiology and Biotechnology
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• v.31 no.3
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• pp.447-455
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• 2021

Strains of four Bacillus spp. were respectively inoculated into sterilized soybeans and the free amino acid profiles of the resulting cultures were analyzed to discern their metabolic traits. After 30 days of culture, B. licheniformis showed the highest production of serine, threonine, and glutamic acid; B. subtilis exhibited the highest production of alanine, asparagine, glycine, leucine, proline, tryptophan, and lysine. B. velezensis increased the γ-aminobutyric acid (GABA) concentration to >200% of that in the control samples. B. sonorensis produced a somewhat similar amino acid profile with B. licheniformis. Comparative genomic analysis of the four Bacillus strains and the genetic profiles of the produced free amino acids revealed that genes involved in glutamate and arginine metabolism were not common to the four strains. The genes gadA/B (encoding a glutamate decarboxylase), rocE (amino acid permease), and puuD (γ-glutamyl-γ-aminobutyrate hydrolase) determined GABA production, and their presence was species-specific. Taken together, B. licheniformis and B. velezensis were respectively shown to have high potential to increase concentrations of glutamic acid and GABA, while B. subtilis has the ability to increase essential amino acid concentrations in fermented soybean foods.

• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.145-148
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• 2003

Previously, we reported that L-PCA enhanced blood circulation by modulating constitutive NO production. It was that L-PCA increased L-Arg uptake into endothelial cell, followed by the enhancement of NO production. Then we recommended the use of L-PCA for cosmetics, not only as humectants but also as enhancer of blood circulation. Since L-Arg is transported into endothelial cells by CAT (cationic amino acid transporter), it is expected that L-PCA also increase the uptake of basic amino acid, L-Lys. In this study, the uptakes of some amino acids into cells were evaluated by using 3H-labelled amino acid. Then we found the tendency that the uptake of L-Lys into endothelial cells was also enhanced by L-PCA. And the evident effect was observed in the epidermal fibroblasts, which had also CAT. Furthermore, it was found that the transportation of the other type of amino acids were not enhanced by L-PCA. That is to say, a famous moisturizer, L-PCA, has some effects on basic amino acid transport into cells.

• Korean Journal of Poultry Science
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• v.42 no.1
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• pp.87-100
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• 2015

It is well known that dietary protein affects the growth performance and carcass composition of poultry. Over the last several decades, numerous studies have been carried out to investigate to optimize the level of dietary protein since the protein is an important and expensive constituent in poultry feed. It is generally accepted that dietary protein should represent a balance of amino acids supporting the requirements for growth and maintenance of birds. A protein with balanced essential amino acids that matches a bird's requirement and sufficient non-essential amino acid nitrogen to enable the synthesis of all of the non-essential amino acids, is referred to as an 'ideal protein'. Feeding of excess protein or amino acids may result in an amount of nitrogen emission. Most common method to reduce nitrogen emission is using diet formulation which has lower dietary crude protein level and higher concentration of amino acid supplements. However, there are conflicting reports whether low protein diets supplemented with synthetic amino acids can obtain the growth performance equal to high protein diets. Excessive nitrogen excretion caused by amino acid imbalance also may influence the environment of poultry house due to ammonia production from uric acid. These environmental conditions may increase the incidence of skin problem or respiratory diseases of chickens. Various strategies based on comprehensive understanding should be tested to optimize nitrogen utilization and reduce nitrogen emission while maintaining the performance in poultry production.

• Journal of Microbiology and Biotechnology
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• v.10 no.5
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• pp.573-579
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• 2000

Knowledge on the enzymes acting on p-amino-acid-containing peptides appears to be somewhat limited when compared with those acting on peptides composed on L-amino acids. Less than ten D-stereospecific enzymes are hitherto known. This review describes about several novel D-stereospecific peptidases and amidases of microbial origin, including D-aminopeptidase (E.C. 3.4.11.19), alkaline D-peptidase, and D-amino aicd amidase, which are applied to the synthesis of D-amino acid/or D-amino acid derivatives.

• Korean Journal of Pharmacognosy
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• v.29 no.4
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• pp.360-364
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• 1998

To develop new elicitors inducing the high productivity of taxane derivatives, plant growth inhibitors, namely, maleic acid hydrazide, N-phosphomethyl glycine and succinic acid 2.2-dimethyl hydrazide, coconut milk and yeast extract were administrated in the cell suspension culture system of Taxus cuspidata, and the production of baccatin III were analysed. The effects of amino acid related with the biosynthesis of baccatin III were also examined in these culture system. As the results, a remarkable enhancement of baccatin III production was observed in the cultivation with coconut water and with maleic acid hydrazide.

• Microbiology and Biotechnology Letters
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• v.27 no.3
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• pp.184-190
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• 1999

To acquire an industrially useful biocatalyst for the enzymatic synthesis and production of various D-amino acid aminotransferase (D-AAT) activity. The enzyme activity was found from 110 strains of isolated thermophiles revealing its wide occurrence in thermophiles. Enzyme activity and thermal stability of the D-AAT producers were compared. Finally we have selected four thermophiles as producers of potent biocatalysts for the D-amino acid production; two thermophiles, Bacillus sp. Lk-1 and LK-2, having higher specific activity and two thermophiles, B. stearothermophilus KL-01 and Bacillus sp. KLS-01, having higher thermal stability than the D-AAT producers. Taxonomic and physiological characteristics of the four isolated thermophiles were described herein.

• Journal of Dairy Science and Biotechnology
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• v.41 no.1
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• pp.34-43
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• 2023

Hydrolysis of whey-derived proteins using lactic acid bacteria (LAB) utilizes the mass culture method and fermentation of LAB to produce effective bioactive peptides. Whey protein has the biological potential of its precursors, but the active fragments may not be released depending on the hydrolysis method. As an alternative to these problems, the nutritional and bioactive functionality of the hydrolysis method have been reported to be improved using LAB for whey protein. Peptide fractions were obtained using a sample fast protein liquid chromatography device. Antioxidant activity was verified for each of the five fractions obtained. In vitro cell experiments showed no cytotoxicity and inhibited nitric oxide production. Cytokine (IL [interleukin]-1α, IL-6, tumor necrosis factor-α) production was significantly lower than that of lipopolysaccharides (+). As a result of checking the amino acid content ratio of the fractions selected through the AccQ-Tag system, 17 types of amino acids were identified, and the content of isoleucine, an essential amino acid, was the highest. These properties show their applicability for the production of functional products utilizing dietary supplements and milk. It can be presented as an efficient method in terms of product functionality in the production of uniform-quality whey-derived peptides.

• Plant Resources
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• v.5 no.1
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• pp.78-85
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• 2002

The material of Rhodiola sachatinensis collected from an alpine region of the west-northern China. For analysing the effect, 1 used Rhodiola sachatinensis's rhizome and cultivated callus. In EtOAc, BuOH, $H_2O$ separation the plant showed strong antioxidative activity, but not in Hexane. The radical scavenging effect of EtOAc(RC$_{50}$,35(g), BuOH(RC$_{50}$, 43(g), H$_2$0(RC$_{50}$, 50(g) fraction and MeOH extract(RC$_{50}$, 50(g) of the Rhodiola sachatinensis was comparable to that of synthetic antioxidant BHA(RC$_{50}$, 14(g) and $\alpha$-Tocopherol(RC$_{50}$, 12(g). Total amino acid concentration of plant of In nature condition were 18,009ppm, and major components were arginine, glutamic acid, aspartic acid and valine. The ratio of essential/total amino acid on plant of In nature condition was 46.93%. Total amino acid concentration of callus of In vitro condition were 32,435ppm, and major components were valine, histidine, lysine and leucine. The ratio of essential/total amino acid on callus of In vitro condition was 56.07%. was 56.07%.