• Journal of Microbiology and Biotechnology
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• v.33 no.7
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• pp.857-863
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• 2023

Pathogenic bacteria that colonize the human intestinal tract have evolved strategies to overcome acidic conditions when they pass through the gastrointestinal tract. Amino acid-mediated acid resistance systems are effective survival strategies in a stomach that is full of amino acid substrate. The amino acid antiporter, amino acid decarboxylase, and ClC chloride antiporter are all engaged in these systems, and each one plays a role in protecting against or adapting to the acidic environment. The ClC chloride antiporter, a member of the ClC channel family, eliminates negatively charged intracellular chloride ions to avoid inner membrane hyperpolarization as an electrical shunt of the acid resistance system. In this review, we will discuss the structure and function of the prokaryotic ClC chloride antiporter of amino acid-mediated acid resistance system.

• Food Science and Preservation
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• v.13 no.5
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• pp.581-588
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• 2006

Dynamic changes of free sugar and amino acid in the mixture of red bean paste sediment by corn syrup concentration and heating conditions were monitored. Glucose and fructose contents of red bean paste increased with an increasing blown color intensity. Amino acid content was affected by the heating temperature, increased with an increase in browning color intensify. Browning color intensity of each samples increased up to $95^{\circ}C$, but decreased above $95^{\circ}C$. This result was the same tend as changes of glucose and amino acid. The result of correlation coefficients among free sugar amino acid and browning color intensity show that increase in browning color intensity was not correlated directly with changes of free sugar and amino acid content. It seems that the contents of free sugar and amino acid resolved from saccharides and protein were much mote than contents nea for browning reaction.

• Journal of Environmental Health Sciences
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• v.12 no.1
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• pp.63-67
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• 1986

The contents of amino acid in alcoholic beverage-Cheongju, Beer, Makguli, grapewine were analyzed. Cheongju and Makguli were filtered with membrane filter paper. Beer and grapewine were also filtered after treatment with 5-Sulfosalicylic acid. Sample were analyzed by Amino Acid Analyzer (Hitach KLA-5). The results were as follow: 1. The kinds of Amino Acid in Cheongju were 18, those of Beer were 17, Makguli 15, and grape wine 10. 2. The total amino acid in Cheongju was 54.0295 mg, Beer was 16.7172mg, Makguli was 12.3833 mg and grape wine was 4.1480 mg in 100 ml volume.

• Korean Journal of Food Science and Technology
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• v.5 no.2
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• pp.71-77
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• 1973

The results, which was analytically surveyed the free amino acids by the automatic amino acid analyzer adding the enzyme on the Korean cow's fore shank muscles, are as follows: 1. The content of free amino acids in the fore shank muscles, without addition of the enzyme orderly contains alanine, glutamic acid, lysine, glycine, histidine, leucine, threonine, arginine, cystine, serine, proline, isoleucine, phenylalanine, tyrosine, methionine, aspartic acid and valine. 2. In accordance with the addition of the enzyme, by 0.01%, 0.05% and 0.1% the nine free amino acids of glutamic acid, glycine, alanine, cystine, valine, isoleucine, leucine, lysine and arginine were continuosly increased. 3. Proline and histidine were decreased at the enzyme addition of 0.01% after showing the high content at the control, but the quantity of free amino acids was increased according to the increase of the quantity of the enzyme. 4. Aspartic acid, threonine, serine, methionine, tyrosine and phenylalanine were increased till the enzyme addition of 0.05% and remarkably decreased from 0.1%. 5. At cooking the meat, the quantity of the enzyme addition was most effective at 0.05% of meat weight.

• Korean Journal of Food Science and Technology
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• v.8 no.3
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• pp.129-135
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• 1976

The amino acid compositions of polished barley grain were investigated for 16 varieties by using amino acid autoanalyzer and simple correlation analysis between them and between protein and amino acid per protein was done. 1) Limiting amino acid is lysine, leucine and phenylalanine are high but threonine and tyrosine are low. Total essential amino acids is high. 2) Protein is significantly correlated negatively with lysine arginine, total basic amino acids (at p=0.01) and threonine, alanine, aspartic acid (at p=0.05) and positively with phenylalanine (at p=0.01) proline and cystine (at p=0.05). 3) Lysine is positively and significantly correlated with arginine and aspartic acid indicating that aspartic acid is probable precursor of lysine and that high yielding varieties or fertilization for high yielding decrease aspartic acid pool resulting low lysine. 4) Lysine content is positively correlated with dye binding capacity (at p=0.01). 5) Tryptophan is positively (at p=0.01) and significantly correlated with histidine, total basic amino acids and arginine. 6) In essential amino acids lysine, tryptophan, threonine and valine simultaneously increase or decrease while aromatic amino acids, sulfur contained amino acids, isoleucine and leucine do so together.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.2
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• pp.136-143
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• 1988

This study was performed to provide the optimal conditions of quantitative analysis for free amino acid in fermented protein foods. The water extractable free amino acid from dairy fermented foods was extracted effectively at $75^{\circ}C$ for 40 min., while it were extracted from fermented soy products at $40^{\circ}C$ for 3 hours. A close results of free amino acid content to those from amino acid analyzer were obtained using OPDA method with lysine standard after deproteinizing with 1% picric acid. 95% ethanol used as a deproteinizing reagent could give a comparable results to those from picric acid treatment in determining free amino acid content using OPDA method. Therefore, ethanol treatment was more recommendable than picric acid treatment which has some troubles in removing excess picric acid through Dowex resin column. The most desirable precipitation method for free amino acid determination using TNBS method was 95% ethanol treatment among the various deproteinizing procedure. The copper salt method was not suitable owing to its lacking reproducibility and pronounced discrepancy in determining free amino acid.

• Journal of Microbiology
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• v.39 no.3
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• pp.229-231
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• 2001

Different DL-amino acids were studied as inducers of D-amino acid oxidase (DAAO) and for their influence on the growth of Trigonopsis variabilis. DL-amino acids with non-polar side groups were found to be the befit inducers of DAAO. Maximum increase in the growth of Trigonopsis variabilis (gram dry weight per liter culfure) was observed with DL-methionine (2.39 g/l) followed by DL-serine (2.22 g/l) and DL-alanine (2.21 g/l).

• Korean Journal of Pharmacognosy
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• v.7 no.1
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• pp.63-67
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• 1976

The composition of amino acids in seeds of three species of Gleditsia, Gleditsia japonica var. Koraiensis, Gleditsia japonica var. Imarmatu, and Gleditsia officinalis Hemsley, were determined by the Amino-Acid Autoanalyzer (Technicon PNC-1). Total contents of amino acids were less than that of ordinary edible soybean and an undetermined amino acid was found. The undetermined amino acid showed an absorption peak between histidine and arginine.

• The Korean Journal of Food And Nutrition
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• v.11 no.4
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• pp.437-443
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• 1998

This research is to establish the basic data of the nutritive value and improve our diet. In the part of the leaf and stem of the wild and cultivated horned rampion (Phyteuma japonicum Mig), the components such as chemical compositon, vitamin C, free sugar, mineral, nucleotide and its related compounds, composition and free amino acid were analyzed one after another. Content of the crude lipids and proteins was determined much higher in its wildness than in its cultivated horned rampion; while, that of carbohydrates was higher in the former than in the latter. The content of vitamin C was retained higher in the leaf than in the stem horned rampion. And the content of calcium among the detected minerals was outstanding in all of the samples collected, and potassium and magnesium was the next ones in its order. The main components of free sugars in both the wild and cultivated horned rampion were glucose and fructose, and their content was higher in the stem than in the leaf. Nucleotide and its related compounds were identified with 5 kinds of nucieotides such as CMP, UMP, IMP, AMP and hypoxanthine (Hx), and the content of Hx and AMP was the highest I the wild and cultivated samples, respectively. In the composition amino acid of the wild horned rampion, glutamic acid, aspartic acid and phenylalanine was outstandingly abundant; while, such amino acid as methinone and proline was small and besides cysteine couldn't be detected in the stem. Total amounts of composition amino acid in the leaf was 2118.0 and 1120.1mg% in the wild and cultivated sample, respectively. In the free amino acid of horned rampion, the total amount ranged from 8.5 to 50.1mg.%, which were lower level than that of composition amino acid. But the number of free amino acid was 29 kinds, which was bigger in its number than that of composition amino acid detected 17 kinds.

• Journal of Nutrition and Health
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• v.20 no.6
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• pp.456-462
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• 1987

Chemical composition, free amino acid and fatty acid composition of wild and cultured cockle clam were studied. 1. The content of crude protein was higher in Anadara suberenata thanthat ini Anadara granosa. The contents of crude protein and ash increased after boiling. 2 Free amino acid composition of Anadara granosa was similar to that of Anadara suberenata. Both glutamic acid and aspartic acid among free amino acid were the most abundant in cockle clam. Next, leucine, arginine and lysine were abundant in order. They all composed of approximately 50%^ of total amino acid content. Whereas the contents of cystine and methionine were poor. 3. In cockle clam the major fatty acids consisted of C16 :0, C18: 0, C18 ;1 and C18:3 in order. The level of C16 :0 was the highest in lipids. The levels of C18 : 0 and C14 :0 were higher in Anadara granosa than those in Anadara suberenata, while the levels of C16 :0, C18 :3 and C16 : 1 were higher in Amadara suberenata than those in Anadara granosa.