• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.4
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• pp.295-299
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• 2004

The prices of domestic green tea products are relatively expensive and price differences within products of the same levels of quality are various. Also, there is no basic criteria on evaluation of green tea quality. To group 43 commercial green tea products into several parts by the principal component and cluster analyses, this work was done by use of 8 chemical constituents which were analyzed by NIR system. The principal component and cluster analyses revealed 8 groups. The first group included 16 products that had lower free amino acid and theanine contents. The second group included 5 products having higher free amino acid and theanine contents, but lower ash contents. The third group included 13 products showing medium values of 8 constituents. The IV group included 4 products having higher contents of moisture, free amino acids, and theanine. The V group included 1 product showing higher moisture but lower catechins contents. The VI group included 2 products that had higher moisture and catechins contents, but lower free amino acid and theanine contents. The VII group had higher moisture and catechins contents. The VIII group had higher ash and vitamin C contents. The free amino acid contents which were the most important in flavor evaluation of green tea quality did highly positively correlate with the contents of total nitrogen $(0.956^{**}),\;theanine\;(0.981^{**}),\;and\;caffeine\;(0.793^{**})$, but negatively with the contents of ash $(-0.884^{**})$. The catechins used as for functional ingredients did correlate with contents of caffeine(+) and vitamin C(-), respectively.

• Ocean and Polar Research
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• v.35 no.4
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• pp.273-280
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• 2013

The proximate composition, free amino acid composition and mineral contents from Undariopsis peterseniana were determined, and the antioxidant activities of ethanol (EtOH) and hot water extracts of U. peterseniana were investigated using DPPH (1,1-diphenyl-1-picrylhydrazyl), ABTS (2,2'- azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)) radical scavenging effects and reducing power. The contents of moisture, ash, protein, lipid and carbohydrate were 12.5%, 23.1%, 9.7%, 0.2% and 54.5%, respectively, and alginic acid content was 12.3%. The major free amino acid contents were alanine, phenylalanine, aminoethanol, valine, glutamic acid and phosphoserine. Ca (1589.1 mg) was the largest mineral followed by Na (344.6 mg), Mg (74.3 mg), Zn (10.2 mg) and Fe (1.5 mg). The total phenolic contents of EtOH and hot water extracts were exhibited at 15.7 and 4.3 mg GAE/g sample, respectively. The antioxidant activity of EtOH extract exhibited strong ABTS and DPPH radical scavenging activities with reducing power, and hot water extract also demonstrated strong ABTS radical scavenging effects. Therefore, the results of this study suggest that U. peterseniana contained an abundance of naturally occurring nutrients (free amino acids and minerals), and the strong antioxidant activities of EtOH and hot water extracts from U. peterseniana could be good sources of natural antioxidants for healthcare products.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.11 no.2
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• pp.65-83
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• 1978

This study was attempted to evaluate the taste of broiled-dried sea mussel which is a traditional dried Sea food in Korea. The contents of such compounds as free amino acids, nucleotides and their related compounds, TMAO, betaine, and nonvolatile organic acids were analysed. From the results of analysis of nucleotides, the contents of AMP and ADP in broiled-dried Mytilus coruscus and Mytilus edulis appeared higher than other nucleotides and tended to increase slightly after cooking, drying, and storage which might be due to both their stability and the addition of degradation of nucleic acids during cooking. In the free amino acid composition of fresh samples abundant amino were taurine, glycine, serine, glutamic acid, alanine, arginine, threonine, tyrosine, lysine and valine in order. Such amino acids as histidine, leucine, methionine and isoleucine were poor and both proline and phenylalanine were merely trace. The free amino acid composition in the extract of Mytilus corucus and Mytilus edulis after broil-drying was not changed. These amino acids, taurine, glycine, feline, glutamic acid, alanine and arginine were abundant in dried samples as well as in the fresh. The total free amino acid was greatly reduced after cooking and drying ranging from $76.3\%$ to $79.7\%$ loss to that of tile fresh. The content of betaine shelved the same tendency as in total free amino acid while TMA slightly increased relating to TMAO decrease during broil-frying. Such nonvolatile organic acids as succinic, lactic, malic and fumaric acid were abundant in both fresh and broiled-dried samples whereas oxalic and pyruvic acid were poor. It is found that the taste compounds of broiled-dried Mytilus coruscus and Mytilus edulis were composed of amino acids as glycine, serine, alanine, glutamic acid, arginine, and betaine, TMAO, ADP, AMP, and organic acids such as succinic acid, lactic acid, malic acid and fumaric acid. No significant differences in the taste compounds between male and female as well as between Mytilus coruscus and Mytilus edulis was not observed.

• 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.

• Korean Journal of Environmental Agriculture
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• v.30 no.4
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• pp.402-408
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• 2011

BACKGROUND: Effect of various light wavelength and plant defense molecules were evaluated on the hardness and the contents of free amino acid including ${\gamma}$-aminobutyric acid (GABA) in soybean sprouts. METHODS AND RESULTS: Germinating soybean seeds were treated with various single wavelength of light (380, 440, 470, and 660 nm) or without light at $25^{\circ}C$ for six days. Soybean seeds were also treated with stress-signaling molecule ethephon or $H_2O_2$ at the same time. Soybean sprouts treated with 470 nm substantially raised the hardness almost two times than the control. The free amino acid contents were higher in 470 nm and $H_2O_2$ treated soybean seeds than the control. Nutritionally beneficial GABA contents were increased by the treatments of 470 nm, 440 nm, ethephon, and $H_2O_2$. CONCLUSION: These results suggest that the hardness and the contents of amino acids can be regulated by stimuli, which stimuli could be composed of various wavelength and plant defense molecules. Especially, single wavelength 470 nm illumination has the effect of increasing GABA contents with increased hardness.

• Journal of Ginseng Research
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• v.40 no.2
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• pp.113-120
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• 2016

Background: The present study aimed to compare the relative abundance of proteins and amino acid metabolites to explore the mechanisms underlying the difference between wild and cultivated ginseng (Panax ginseng Meyer) at the amino acid level. Methods: Two-dimensional polyacrylamide gel electrophoresis and isobaric tags for relative and absolute quantitation were used to identify the differential abundance of proteins between wild and cultivated ginseng. Total amino acids in wild and cultivated ginseng were compared using an automated amino acid analyzer. The activities of amino acid metabolism-related enzymes and the contents of intermediate metabolites between wild and cultivated ginseng were measured using enzyme-linked immunosorbent assay and spectrophotometric methods. Results: Our results showed that the contents of 14 types of amino acids were higher in wild ginseng compared with cultivated ginseng. The amino acid metabolism-related enzymes and their derivatives, such as glutamate decarboxylase and S-adenosylmethionine, all had high levels of accumulation in wild ginseng. The accumulation of sulfur amino acid synthesis-related proteins, such as methionine synthase, was also higher in wild ginseng. In addition, glycolysis and tricarboxylic acid cycle-related enzymes as well as their intermediates had high levels of accumulation in wild ginseng. Conclusion: This study elucidates the differences in amino acids between wild and cultivated ginseng. These results will provide a reference for further studies on the medicinal functions of wild ginseng.

• Food Science and Preservation
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• v.6 no.1
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• pp.61-65
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• 1999

This study was carried out to investigate change in the components according to drying methods of jujube. Raw jujube was dried with five methods such as sun-drying, hot-air drying after pretreated with sunlight, blanching, microwave treatment, respectively. The contents of soluble sugar and protein in sun-dried jujube were higher than those of other drying methods. The free sugars of dried jujube were consisted of sucrose, glucose and fructose. And the contents of free sugar was not different by drying methods. The major organic acids of dried jujube were oxalic acid, citric acid and malic acid. The contents of glutamic acid, glycine and alanine were higher than those of other amino acids, and the content of each amino acid was not different by drying methods.

• The Korean Journal of Food And Nutrition
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• v.37 no.2
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• pp.123-127
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• 2024

The fatty acid composition and free amino acid content of domestic soybean cultivars were analyzed to confirm the quality characteristics of protein and fat contained in soybeans. The saturated fatty acid content of soybeans included palmitic acid at 9.47~11.15%, followed by stearic acid and myristic acid. The total saturated fatty acid content in soybeans was 12.56~14.34%, with Taekwang having the lowest content, followed by Daewon, Seonyu, Cheonga, and Jinpung. The linoleic acid content, an unsaturated fatty acid, was 45.69~58.17%, with Taekwang showing the lowest composition and Jinpung showing the highest composition. Next was oleic acid at 14.69~33.86%. Jinpung had the highest linoleic acid composition, had the lowest and Taekwang which had the least linoleic acid, had the highest. The unsaturated fatty acid content was in the order of linolenic acid, eicosatrienoic acid, eicosadienoic acid, and eicosapentaenoic acid. The total free amino acid content was 217.28~456.66 mg%, with Daewon showing the highest free amino acid content, followed by Seonyu, Taekwang, Cheonga, and Jinpung. The free amino acid content varied depending on the cultivars, but in general, the free amino acids in the soybeans used in the experiment showed higher aspartic acid, glutamic acid, and proline contents than other amino acids.

• The Journal of the Korea Contents Association
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• v.20 no.2
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• pp.451-461
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• 2020

This study was carried out to investigate the value of yellow cherry tomato as a food material. Contents of nutritional and bioactive compound were determined from yellow cherry tomato. 17 of amino acids occurred. L-Glutamic acid (45.15%), L-glutamine (22%) and L-aspartic acid (11%) were the main amino acids. 8 of essential amino acids were found except tryptophan. γ-aminobutyric acid (GABA) was found in high contentration (258.58 mg/100g). Contents of Lycopene and β-carotene were 2.18 mg/100 g and 9.90 mg/100 g, respectively. Yellow cherry tomato contained naringenin chalcone, quercetin-3-rutinoside(rutin), 5-caffeoylquinic acid, 3-caffeoylquinic acid, and quercetin-3-apiosylrutinoside that have various bioactivities. These results revealed that yellow cherry tomato would be very useful and valuable food material.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.1
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• pp.89-93
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• 1991

For the investigation of major taste components in loquat(Eiobotrya japonica) flesh its conte-nts and compositions of free sugars organic aicds and free amino acids were analyzed Major free sugars of the fully ripened loquat were fructose glucose and sucrose and their contents were 3,71, 3.42 and 0.46%(w/w) respectively. The content of total sugar 13.7% was 2 times higher than that of the unripe fruit. The content of total organic acid was about 0.2% (w/w) and major organic acids were malic acid -89mg% formic acid -32mg% and oxalic acid -26%mg% Thirteen kinds of free amino acids from the fully ripened loquat were confirmed. Major free amino acids were aspartic acid valine glutamic acid serine alanine and histidine and their contents were in the range of 18-30mg%.