• Journal of the Korean Chemical Society
• /
• v.8 no.2
• /
• pp.85-87
• /
• 1964

In order to stabilze alloxan as a reagent for detection of amino acids by spot test, sugars and other reductants were added to the aqueous alloxan solution. It was found that lactose was the best for the purpose. The alloxan reagent containing lactose did not give color change on blank test and was very stable that there was no color change even it was allowed to stand in room temperature for several months. The color reaction with amino acids and some amines was not affected by lactose. This spot test for amino acids is in sensitivity as comparable to that of the previously reported methods and gave color reaction with proline and hydroxyproline to 1${\gamma}$ and 5${\gamma}$ respectively.

• Preventive Nutrition and Food Science
• /
• v.1 no.1
• /
• pp.16-22
• /
• 1996

Amino acids and ribonucleotides were measured for boiled-dried anchovy to determine the effect of 5 kGy γ-irradiation on its quality stability during storage at ambient and cooling (5∼10℃) temperatures for 12 months in a laminated-film package(Polyethylene 10㎛). The anchovy samples contained about 55%(d.b) of total amino acids and about 1%(d.b) of free amino acids. Although there found a significant change(p<0.01) in the content of leucine and lysine immediately sfter irradiation, the overall content of toral amino acids was little changed in stored anchovy even six months after irradiation at cooling conditions. γ-Irradiation caused a significant reduction(p<0.01) in the total content of free amino acids, showing a similar tendency by storage conditions. However, the ribonucleotides. which were 12.00mg/g(d.b) in inosine-5'-monophosphate and 0.38mg/g(d.b) in guanosine-5'-monophospate, were resistant to 5kGy-irradiation. With the lapse of storage time, it was also shown that storage temperature was more influential than irradiation on the contents of amino acids and taste compounds of dried anchovy.

• Bulletin of the Korean Chemical Society
• /
• v.32 no.spc8
• /
• pp.3017-3021
• /
• 2011

Two chiral stationary phases (CSPs) based on (3,3'-diphenyl-1,1'-binaphthyl)-20-crown-6 bonded covalently to silica gel were applied for the first time to the resolution of racemic vigabatrin and its analogue ${\gamma}$-amino acids and the resolution results were compared to those on the commercially available Crownpak CR(+) based on (3,3'-diphenyl-1,1'-binaphthyl)-20-crown-6 coated dynamically onto octadecylsilica gel. While vigabatrin was not resolved at all on Crownpak CR(+), it was resolved quite well on the two CSPs. Among four vigabatrin analogue ${\gamma}$-amino acids, only two were resolved on Crownpak CR(+), but three were resolved on the CSP (CSP 1) containing residual silanol groups and all of four were resolved on the CSP (CSP 2) containing residual silanol group-protecting n-octyl groups. The improved lipophilicity in CSP 2 was proposed to be responsible for its superiority to CSP 1 for the resolution of vigabatrin and analogue ${\gamma}$-amino acids. In addition, the composition of aqueous mobile phase was found to affect the chiral recognition behaviors for the resolution of vigabatrin and analogue ${\gamma}$-amino acids on CSP 2.

• Korean Journal of Microbiology
• /
• v.5 no.2
• /
• pp.79-85
• /
• 1967

Kim, Jong Hyup., (Div. of Biology, Atomic Energy Research Institute,Korea.;) Studies on the Cellulor Metabolism in Microorganisms as influenced by Gamma-irradiation(III): On the Changes of Free Amino acid Pool and content of Protein in Yeast clls irradiated by .gamma.-ray. 1. The strain of Saccharomyces cerevisiae had been cultured synchronously in aerobic condition and irradiatel by gamma-ray from the source of cobalt-60. Drying in vacuum oven at $90^{\circ}C$ C over 12 hours, then changes of protein content (Kjeldahl) and free amino acid pool have been assayed with use of spectrophotometer. Results obtained were compared with those of unirradiated normal cells. 2. It is proved that amount of protein content in the irradiated cells increases to seven percent more than those of normal cells in the same weight of dried samples. It seems like carbohydrate breakown had been stimulated by irradiation and that relative contents of protein shows higher values than those of normal in the same weight of samples. 3. The amount of free amino acid pool in the irradiated cells shows less value about ten percent than those of normal cells, and rate of decreasing is also weak than those of standard reagent solution of amino acid. We may assume that free amino acid pool would be protected against radiation damage in living cells and more stable than in vitro. 4. The component of free amino acid pool have been assayed on second dimensional paper chromatogram, and the identified amino acids are as follows; aspartic acid, serine, glutamic acid, cystine, lysine, glycine, threonine, histidine, arginine, tyrosine, phenylalanine, valine and leucine. 5. Distributional presence of free amino acids are identical to that of normal cells except arginine, it is cosumable that radiation effect is univerlsal to all amino acid. However it is obvious that there are differences in radiolabilities of amino acids in irradiated cells.

• The Korean Journal of Physiology and Pharmacology
• /
• v.18 no.5
• /
• pp.371-376
• /
• 2014

Amino-acid neurotransmitter system dysfunction plays a major role in the pathophysiology of depression. Several studies have demonstrated the potential of amino acids as a source of neuro-specific biomarkers could be used in future diagnosis of depression. Only partial amino acids such as glycine and asparagine were determined from certain parts of rats' brain included hippocampi and cerebral cortex in previous studies. However, according to systematic biology, amino acids in different area of brain are interacted and interrelated. Hence, the determination of 34 amino acids through entire rats' brain was conducted in this study in order to demonstrate more possibilities for biomarkers of depression by discovering other potential amino acids in more areas of rats' brain. As a result, 4 amino acids (L-aspartic acid, L-glutamine, taurine and ${\gamma}$-amino-n-butyric acid) among 34 were typically identified as potentially primary biomarkers of depression by data statistics. Meanwhile, an antidepressant called Fluoxetine was employed to verify other potential amino acids which were not identified by data statistics. Eventually, we found L-${\alpha}$-amino-adipic acid could also become a new potentially secondary biomarker of depression after drug validation. In conclusion, we suggested that L-aspartic acid, L-glutamine, taurine, ${\gamma}$-amino-n-butyric acid and L-${\alpha}$-amino-adipic acid might become potential biomarkers for future diagnosis of depression and development of antidepressant.

• Asian-Australasian Journal of Animal Sciences
• /
• v.22 no.2
• /
• pp.296-304
• /
• 2009

The nutritional significance of essential amino acids, as well as non-essential amino acids, is well documented in poultry production with regards to growth performance and protein accretion. However, the function of amino acids in the stress response is still unclear. L-Pipecolic acid, a L-lysine metabolite in the brain, induced a hypnotic and sedative effect acting via the ${\gamma}$- aminobutyric acid receptors. L-Arginine also induced a sedative effect via its metabolism to L-ornithine. In addition, three-carbon nonessential amino acids like L-alanine, L-serine and L-cysteine also induced sedative effects. These facts suggest that the requirement for amino acids in both essential and non-essential types may require reconsideration to add the concept of stress amelioration in the future.

• Korean journal of food and cookery science
• /
• v.29 no.6
• /
• pp.671-677
• /
• 2013

The objective of this study was to examine the levels of free amino acids and identify the correlation between ${\gamma}$-aminobutyric acid (GABA)and L-glutamic acid contents in Kimchi during fermentation. During 2 weeks of fermentation, the acidity of Kinchi increased, i.e., the pH level decreased from 5.24 to 4.40. The content of amino acids determined using HPLC differed significantly (p < 0.05) during 7 weeks of fermentation. Over the 7 weeks of fermentation, the content of most free amino acids increased in the order L-valine > L-glutamic acid > L-glycine, except L-methionine decreased. Initially, the GABA content was found to be $72.43{\mu}M/100g$ fresh weight (fw), and it increased to $229.06{\mu}M/100g$ fw after 7 weeks. This rapid increase in the GABA content in the initial stage is considered to be due to L-glutamic acid. However, during the period of 0~7 weeks, no correlations were found between the L-glutamic acid and GABA contents.

• Journal of Plant Biotechnology
• /
• v.7 no.3
• /
• pp.195-202
• /
• 2005

The effects of constituent amino acids of glutathione (GSH), glutamate (Glu), cysteine (Cys) and glycine (Gly), on GSH synthesis in lettuce seedlings were examined in this study. The GSH concentration of the seedlings was increased to 5.1-fold and 1.6-fold the concentration of the control in the first leaves and roots, respectively, by simultaneous application of these constituent amino acids (Glu+Cys+Gly) at 100 mg/l to the culture solution for two days. In the first leaves and roots of these seedlings, the concentration of GSH was 180.4 and 14.6 nmole/gFW, and non-essential amino acids including Glu, Cys and Gly occupied 93.2% and 84.0% of the total free amino acids, respectively. Application of Cys greatly increased the concentration of GSH in the roots, and application of 50 mg/l Cys increased it to 26.1-fold the concentration in the control. The activity of GSH synthetase was higher in the leaves than in the roots, whereas the activity of ${\gamma}$-glutamylcysteine synthetase was higher in the roots than in the leaves.

• Korean Journal of Agricultural Science
• /
• v.9 no.2
• /
• pp.576-583
• /
• 1982

The variation of free amino acids during the tomato producing was studied using a tomato variety, Kagome 77. The concentration of free amino acids in fresh and heated pulp, and in puree and paste was analyzed by using automatic amino acid analyzer, Hitachi model KLA-5. 1. A significant difference in decomposition rate of glutamine and asparagine among amide group was recognized. For instance, the glutamine decomposed fast and no glutamine was found in the paste, while 56% of asparagine was found in the paste. 2. The diminishing quantity of glutamic acid among acid group was highest among all free amino acids. The quantity of aspartic acid was next to the glutamine. The percents of glutamic acid and aspartic acid left over were 38% and 24%, respectively. 3. Glycine, alanine, valine, isoleucine and leucine of neutral amino acids tended to be reduced a little during the heating, concentrating process. 4. No apparent variation was found for the lysine and histidine belonging to basic amino acids. while arginine increased a little. 5. Tyrosine, phenylalanine and tryptophane of aromatic group seemed to increase a little during the heating process. But the variations of them during the concentrating process were not recognized. 6. The methionine content, sulfur containing amino acid decreased a little throughout the process. But the decrease of ${\gamma}-amino$ butyric acid of non-protein was not apparently recognized. 7. The amino acid contents of fresh pulp were found as following order: glutamic acid>${\gamma}$-amino butyric acid>glutamine>aspartic acid>asparagine. The amino acid contents of paste were as glutamic acid>${\gamma}$-amino butyric acid>aspartic acid and aspargine. The percent distribution of aromatic and basic amino acids increased, even it was not great. 8. When amino acids were analyzed by Hitachi KLA-5, unknown peak which was never app eared in the fresh pulp before tryptophane was appeared when processed. The peak became greater when heated and concentrated. Later it was known that the peak was not due to lysinoalanine or ornithine.

• The Korean Journal of Zoology
• /
• v.2 no.2
• /
• pp.10-14
• /
• 1959

The retinae and the lens bodies of the frogs were hydrolyzed with 20% hydrochloric acid, and their amino acids were separated by paper chromatography. As a result of it the following were confirmed : (1) The retinae and the lens bodies were the same incomposition, and aspartic acid, glutamic acid, serine ,tyrosine, glycine, lysine arginine, threonine, alanine, histidine, proline, methionine, valine , phenylalanine, leucine, and two unknown substances were separated. (2) The free amino acids in the retinae were extracted with 80% ethyl alcohol and then separated by paper chromatography. Though their separation was not so definite , serine, gultaminc acid, and glycine were always separated regardless of the amount of the sample. When the amount of the smaple was enough , $\beta$-alanine , ${\gamma}$-amino butyric acid and methionine +valine were also separated. (2) The free amino acids in the retinae were extracted with 80% ethyl alcohol and then separated by paper chromatography. Though their separation was not so definite, serine, glutamic acid, and glycine were always separated regardless of the amount of the sample . When the amount of the sample was enough, $\beta$-alanine , ${\gamma}$-amino butyric acid and methionine + valine were also separated.