• Development and Reproduction
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• v.22 no.2
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• pp.119-132
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• 2018

GnRH (gonadotropin-releasing hormone) is a supreme hormone regulating reproductive activity in most animals. The sequences of amino acid and nucleic acid of GnRH reported up to now are examined from the evolutionary framework of Chordata. All identified GnRH are classified into GnRH1, GnRH2, or GnRH3. In all three forms of GnRH both N-terminal and C-terminal are conserved, which allows for effective binding to their receptors. The three amino acids in the middle of GnRH1 sequence have altered diversely from the primitive Chordata, which is indicative of the adaptation process to the ambient environment. GnRH2 and GnRH3 sequences are well conserved. There are more diverse modifications in the nucleic acids than in amino acid sequence of GnRH1. These variations can result from meiosis, mutation, or epigenetics and indicate that GnRH is the product of natural selection.

• Journal of the Korean Chemical Society
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• v.21 no.3
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• pp.215-218
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• 1977

We have investigated for amino acid composition, molecular weight and terminal amino acid of the main gliadin protein which was purified by Sephadex column. The results were obtained as follows: 1. The highest content of amino acid was glutamic acid for the main gliadin protein. 2. The molecular weight was estimated 60,200 ${\pm}$200 for the main gliadin protein. 3. Identified N-terminal and C-terminal amino acid of the main gliadin protein were phenylalanine and methionine, respectively.

• KSBB Journal
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• v.15 no.1
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• pp.96-99
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• 2000

Liposome-amino acid conjugates were prepared using phopholipid (dipalmitoylphosphatidylcholine (DPPC) or distearoylph-osphatidylcholine(DSPC)) and hydrophobically modified amino acids (glutamic acid(glu), glutamine(gln) or asparagine(asn)). The size of liposomes was about 100 nm. According to the glucose-induced turbidity changes, liposomes composed of DPPC and glutamic acid have higher glucose binding affinity than liposomes of DPPC-glutamine or DPPC-asparagine. Also, the liposomes were more stable in terms of aggregation or fusion than the others (DPPC-glutamine, DPPC-asparagine and DSPC-amino acids). As a rdsult, stable liposomes with an affinity for glucose could be prepared with DPPC and glutamic acid.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.609-615
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• 1994

Fermented traditional soybean paste(doenjang), koji soybean paste by Aspergillus oryzae, natto soybean paste by Bacillus natto and koji & natto soybean paste by Aspergillus oryzae and Bacillus natto were analyzed for compositions of amino acids and contents of nitrogens. Amino type nitrogen was the highest in fermenting for 90 days as $271{\sim}868\;mg/100g$, and its contents were in the order of koji soybean paste>traditional soybean paste>koji & natto soybean paste>natto soybean paste in all samples tested. In compositions of total amino acids, glutamic and aspartic acids were rich in koji soybean paste but big differences were not observed in all samples. But some differences were observed in free amino acid compositions in all samples, that is, glutamic acid, tyrosine, lysine and aspartic acid were detected more abundantly. Sum of free amino acids for 90 days were in order of koji soybean paste>traditional soybean paste>koji & natto soybean paste>natto soybean paste. The ratios of free to total amino acids were $3.28{\sim}19.81%$ for 45 days, but increased to $10.88{\sim}25.10%$ for 90 days, and in order of traditional doenjang>koji doenjang>koji & natto doenjang>natto doenjang. Methionine and histidine showed higher ratios of free to total amino acid but lower in glutamic acid and aspartic acid. These results suggest that koji and traditional soybean paste of having high ratios of free amino acids to free and total amino acids may be more favorable in soybean paste fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.9
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• pp.1367-1374
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• 2005

Amino acid transporters play an important role in supplying nutrition to normal and cancer cells for cell proliferation. Amino acid transport system L is a major nutrient transport system responsible for the $Na^+$-independent transport of neutral amino acids including several essential amino acids. The system L is divided into two major subgroups, the L-tyre amino acid transporter 1 (LAT1) and the L-type amino acid transporter 2 (LAT2). In the present study, we have examined the expression and functional characterization of system L amino acid transporters in FOB human osteoblast cells. RT-PCR and western blot analysis have revealed that the FOB cells expressed LAT1, LAT2 together with their associating protein 4F2hc. The uptakes of $[^{14}C]_L$-leucine by FOB cells are $Na^+$-independent and almost completely inhibited by system L amino acid transporter selective inhibitor, 2-aminobicyclo-(2,2,1)-heptane-2-carboxylic acid (BCH). These results suggest that the transport of neutral amino acids including several essential amino acids for cellular nutrition into the FOB human osteoblast cells is mediated by system L amino acid transporters.

• Archives of Pharmacal Research
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• v.14 no.1
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• pp.48-51
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• 1991

Amides from amino acid ester and nalidixic acid were synthesized. The solubility characteristics and partition coefficient of the compounds were studied. The hydrolysis of the compounds was studied in the simulated gastric fluid and simulated intestinal fluid. Some compounds showed better antibacterial activity than nalidixic acid.

• Food Science of Animal Resources
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• v.32 no.3
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• pp.369-375
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• 2012

The current study was carried out to investigate the impact of extraction conditions on the free amino acid level and type in beef longissimus muscle. The sample blocks were chiller aged for 1 d and 7 d at $4^{\circ}C$. There are three homogenization speeds (11,000, 19,000 and 24,000 rpm) for bigger and two speeds (11,000 and 13,000 rpm) for smaller homogenizer's dispersing tools were used for evaluation. Results showed that chiller ageing greatly (p<0.05) increased extractable free amino acids, except cystine. Homogenization with the bigger dispersing tool at 24,000 rpm resulted in the highest free amino acid levels for both 1 and 7 d samples. Significant differences (p<0.05) in the mean values of most amino acids due to the effect of speed and interactions between ageing times. However, the speed effect and interaction between ageing with homogenization speed were not significant (p>0.05) for most of the amino acids except valine and isoleucine when using the smaller dispensing tools. The current data indicated that a standardized method for free amino acid types and levels of aged beef samples. In addition, the results also suggested that utilization of a big dispensing tool at high homogenization speed is a better condition for releasing free amino acid contents in beef samples.

• Korean Journal of Food Science and Technology
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• v.4 no.1
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• pp.36-43
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• 1972

A survey of the free amino acids and free sugars in tomato, watermelon, muskmelon, peach and plum was made by means of amino acid autoanalyzer and thin layer chromatography. The results of the survey are summarized as follows. 1) Fifteen amino acids found in fruit were aspartic acid, glutamic acid, alanine, serine, asparagine, lysine, valine, glycine, methionine, histidine, threonine, leucine, isoleucine, proline and arginine, and an unknown was found. 2) Ten kinds of amino acids were detected in tomato, peach and plum, thirteen amine acids in watermelon and muskmelon (edible part), and eleven amino acids in muskmelon (rind). 3) In general, these fruits contained similar amounts of these thirteen amino acids, and although they were not outstandingly high in any one acid they did contain a nutritionally well-balanced mixture. 4) Amino acids found in the greatest amount in fruit were following: glutamic acid and aspartic acid in tomato, asparagine and lysine in watermelon, alanine, serine and aspartic acid in musk-melon, and aspartic acid and serine in peach and plum. 5) Glucose, fructose, sucrose and maltose were detected in all fruit. The contents of glucose and fructose were high, and those of sucrose and maltose were low.

• The Korean Journal of Food And Nutrition
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• v.14 no.2
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• pp.167-174
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• 2001

Soy sauce was prepared with the addition of Gorosoe and bamboos sap instead of tap water to make ordinary soy sauce, respectively. The changes of such compounds during fermentation as minerals, free sugars, organic acids and free amino acids were analyzed. Total mineral contents in the 90 days fermented soy sauce from Gorosoe and bamboos sap were increased by 2.0 and 4.4 times as compared with those of control samples, respectively. Especially the increase of calcium, potassium and magnesium in soy sauce of sapes were derived from those of saps. The sugars were found to be only glucose and galactose in control samples, but they were detected not only above sugar but also fructose and sucrose in soy sauce of saps. Butyric acid in detected organic acid were dominant in all stray sauce samples. In the free amino acid composition of control samples, leucine, phenylalanine, isoleucine, lysine and glutamic acid were abundant amino acids. Amino acid such as isoleucine, leucine and phenylalanine were decreased, the rest 11 kinds of amino acids containing phosphoserine were increased during the fermentation of control samples. Increasing and decreasing patterns of free amino acids during fermentation of sap soy sauce were similar to control samples. Total nitrogen, amino acid nitrogen and ammonia nitrogen were increased during their fermentation.

• Applied Biological Chemistry
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• v.2
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• pp.41-44
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• 1961

The amino acid analysis of ground rice and the crude protein isolated from rice were performed by the most recent method of Moore, Spackman and Stein, using Amberlite IR-120. The effect of carbohydrates on the hydrolysis of rice was found to be definite in losing several amino acids nevertheless Dustin's claim that large excess of hydrolyzing acid reduces the losses of amino acid. Consequantly the removal carbohydrates as much as possible is considered to facilitate the amino acid determination. The amino acid composition of the crude rotein of rice was very similar to that previously found by other investigators.