• Korean Journal of Agricultural Science
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• v.29 no.2
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• pp.78-90
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• 2002

This study was carried out to investigate whether peptide produced from wheat protein by enzyme hydrolysis can be used as a natural antimicrobial agent. Antimicrobial peptide was obtained from wheat protein by protease of 7 species. The produced antimicrobial peptide was purified through ultrafiltration, membrane filtration and HPLC, and molecular weight and amino acid sequence of the purified antimicrobial peptide were determined. Among hydrolysate produced from wheat protein by protease of 7 species, antimicrobial activity was observed for the peptide obtained from Asp. saito protease. The Asp. saito protease did production antimicrobial hydrolysate showing the highest antimicrobial activity at reaction condition of $37^{\circ}C$ and pH 6.0, but not at reaction condition above $50^{\circ}C$. Wheat protein hydrolysate was fractionated by membrane filtration and showed antimicrobial activity between molecular weight 1,000 - 3,000. The antimicrobial activity fraction obtained by membrane filtration was separated through HPLC and showed antimicrobial activity in the peak of retention time 31.1 - 31.8 min. Since after wheat protein protease hydrolysate was heated during 15 min at $121^{\circ}C$, antimicrobial activity was maintained, we could be conviction as heat-stable peptide. Molecular weight of antimicrobial peptide identified by MALDI-mass was 1,633. Amino acid sequence of antimicrobial peptide was cysteine, glycine, prolin, prolin, prolin, valine, valine, alanine, alanine and arginine.

• The Korean Journal of Food And Nutrition
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• v.19 no.4
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• pp.466-472
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• 2006

In order to develop materials of crab-like flavorant, taste compounds including physicochemical characteristics were analyzed in red snow crab cooker effluent(RSCCE) and hepatopancreas. The $30\;^{\circ}Brix$ was a suitable condition in from 1.5 to $40\;^{\circ}Brix$ RSCCE by sensory evaluation. Lactic acid and succinic acid were major compounds in non-volatile organic acids detected in both $30\;^{\circ}Brix$ RSCCE and hepatopanceras. The 5 compounds such as AMP, HxR, IMP, ATP and GMP were major in ATP related compounds of $30\;^{\circ}Brix$ RSCCE, whereas 3 compounds including IMP, GMP and Hx in hepatopanceras. The content of total free amino acids in hepatopancreas was 5.6 times higher than in $30\;^{\circ}Brix$ RSCCE. The major compounds in $30\;^{\circ}Brix$ RSCCE were followed by methionine, lysine, arginine, valine, histidine, alanine, hydroxy proline, and glycine in that order, whereas methyl histidine, leucine, alanine, glutamic acid, glycine, valine, threonine, taurine, isoleucine, and serine were followed in hepatopancreas. By adding 0.5%(w/w) hepatopancreas in $30\;^{\circ}Brix$ RSCCE, crab meat-like odor was kept high level by sensory evaluation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.4
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• pp.325-332
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• 1985

As a series of study for processing low salt fermented fish, this work was undertaken to investigate taste compounds of low sodium salt fermented anchovy and yellow corvenia comparing with conventional fermented fish ($20\%$ of salt contents) during the fermentation of 120 days at $25{\pm}3^{\circ}C$. The major amino acids in fermented anchovy at 60 day fermentation were lysine, alanine, leucine, valine, isoleucine, histidine, threonine and glycine, while those in fermented yellow corvenia at 90 day fermentation were lysine, leucine, alanine, valine, threonine, isoleucine, glutamic acid and methionine. These amino acids held $57\%$ of the total extractive nitrogen content for fermented anchovy and $41\%$ for fermented yellow corvenia, respectively. It was supposed from the results that principal taste compounds both for fermented anchovy and fermented yellow corvenia were free amino acids, and that nucleotides and their related compounds as well as total creatinine also played an assistant role. And also there was little difference between taste compounds of low salt fermented fish and those of conventional fermented fish irrespective of fish species.

• Applied Biological Chemistry
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• v.47 no.4
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• pp.403-408
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• 2004

We studied active substances like crude cell wall components, crude protein, composing amino acids and free amino acids including orinithine cycle-related amino acids such as asparagine, ornithine and citrullin in fully ripe fruits of Korean native squash, Cucurbita moschata Poir. Crude protein content of 'Jeju 2' was the highest with $2,830\;{\mu}g/g$, while 'Sangju' was the lowest with $1,319\;{\mu}g/g$. Regarding the contents of crude cell wall components, fruit 'Kanghaw' was the highest with 2,961 mg% while 'Namhea' was the lowest with 1,582 mg%. Pectin contents of crude cell wall components were the highest in 'Kanghaw' (2,198 mg%) followed by 'Jeju 2' (2,178 mg%) and 'Jeju l' (1,461 mg%). The main contents of amino acids in squash were glutamic acid, aspartic acid, lysine, leucine and valine, which comprised to be more than 50% of total amino acid contents. Especially, in 'Jeju 2' aspartic acid and threonine were not detected. In fully ripe fruits, a total of 34 kinds of free amino acids were detected including 8 kinds of essential amino acids (histidine, isoleucine, leucine, lysine, phenylalanine, methionine, threonine and valine). More than 50% of the total free amino acids were aspartic acid and asparagine, and also all varieties were detected in ornithine, citrullin, and arginine, which are related to Ornithine cycle. There was a big difference in the contents of arginine in all varieties whereas the contents of ornithine and citrullin were very similar. 'Teaan' 29.34% was 7 times higher than 'Namhea' 4.30% in regards to arginine contents.

• Korean Journal of Food Science and Technology
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• v.8 no.4
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• pp.225-229
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• 1976

Gulbi, salted and dried yellow corvenia, is one of widely consuming fish foods in this country. This study was attempted to establish the basic data for evaluating the taste compounds of Gulbi. The free amino acids were analysed by amino acid autoanalyser. In the free amino acid composition of raw yellow corvenia, abundant amino acids were glutamic acid, alanine and lysine and then leucine, glycine, serine and threonine in order. Such amino acids like proline, valine, methionine, tyrosine and phenylalanine were poor in content. The changes of free amino acid composition in the extract of yellow corvenia during Gulbi processing was not observed. In the extract of Gulbi product, glutamic acid, lysine, leucine, alanine and valine were dominant holding 20.0%, 12.9%, 11.1%, 10.1% and 8.5% of total amino acids respectively. The amounts of total free amino acids of yellow corvenia increased more than 3.6 times as compared with that of raw sample during Gulbi processing. It is convinced that the characteristic flavor of Gulbi was attributed to such amino acids like lysine and alanine known as kweet compounds, as glutamic acid with meaty taste, and as leucine known as bitter taste.

• Journal of Korean Society of Forest Science
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• v.79 no.4
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• pp.345-351
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• 1990

The seeds of Korean pine, Pinus koraiensis, had been used as one of edible fruits for long time, but its chemical analysis of the nutrient components was extremely limited. The purpose of this study is to analyze the content of chemical components of Korean pine seeds. The results obtained are as follows : 1. In general analysis of Korean pine seeds, moisture is 4.4%, crude protein 18.3%, crude fat 67.3%, crude fiber 4.7%, ash 2.2%, and nitrogen-free extract 3.4%, respectively, 2. The Korean pine seed contained 18 different kinds of amino acid : lysine, histidine, arginine, aspartic acid, threonine, serine, glutamic acid, proline, glycine, alanine, valine, methionine, isoleucine, leucine, tyrosine, phenylalanine, cysteic acid, and tryptophan. The glutamic acid is highest content among 18 kinds of amino acid. 3. The Korean pine seed contains all the essential amino acids such as arginine, histidine, lysine, threonine, valine, methionine, isoleucine, leucine, phenylalanine, and tryptophan. 4. The Korean pine seed contains 13 different kinds of fatty acid such as myristic acid, palmitic acid, palmitoleic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, arachidic acid, 9-icosenoic acid, 9, 11-icosenoic acid, 8, 11, 14-icosatrienoic acid, and tn-o unknown substances. Also it contains all the essential fatty acids as linoleic acid and linolenic acid. The linoleic acid is highest content among 13 kinds of fatty acid. 5. The Korean pine seed contained 5 different kind., of vitamin such as vitamin A, vitamin $B_1$, vitamin $B_2$, vitamin E and niacin. The content of vitamin E is the largest among 5 kinds of vitamin.

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.269-277
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• 2008

Amino acid composition in grain of Korean native rice core collections was evaluated to identify the useful genotypes for quality enhancing rice breeding and value-added food development. Large variations were found in the contents of 16 amino acids among 388 genotypes tested with 14.9% of the minimum coefficient of variation (CV), and the contents of methionine and histidine showed the highest CV and the second high, respectively. The average values of total amino acid, total essential amino acid, lysine and threonine contents of Korean native rice collections were almost similar with those of cultivating japonica rice, Saechucheong. Among 388 native core collections Baekkokna, Daesona and Saducho were identified as high amino acid germplasm in total amino acid, total essential amino acid, lysine and threonine contents. And Seoksanjo and Sodujo were identified as low amino acid collections. Rice collections showing purple apiculus color tended to distribute in lower serine, proline, glutamic acid, glycine, alanine, valine, leucine, phenylalanine, arginine, and total amino acid contents compared with those of yellowish apiculus color collections. The glutinous rice collections showed the tendency of higher contents of serine, glutamic acid, alanine, valine and leucine compared with those of non-glutinous collections.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.8
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• pp.523-530
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• 2019

This study was performed to develop Sulgidduk prepared with different levels (0, 3, 6, 9 and 12%) of defatted mealworm powder and to evaluate the characteristics of this Sulgidduk. We performed an assessment of color values, mechanical properties, general compositions and branched amino acids of Sulgidduk prepared with different levels of defatted mealworm powder. For the color values, the lightness(L) was decreased with increased amount of defatted mealworm powder, while the redness(a) and yellowness(b) were relatively increased. For the mechanical properties, the hardness and gumminess were significantly increased according to the increased amounts of defatted mealworm powder, but the chewiness, springiness and cohesiveness showed significant differences. For the sensory evaluation, the overall quality of Sulgidduk prepared with 6% defatted mealworm powder (MS-6) was higher as compared with that of the other Sulgidduk samples. For the general composition, the moisture and crude ash contents of MS-6 did not shown differences, while the crude protein was higher than those of the control, and the carbohydrate content of the control was higher than that of the MS-6. The contents of branched amino acids (valine, leucine and isoleucine) of MS-6 were higher than those of the control. Therefore, it was concluded that MS-6 could be a protein rich food as a good source of branched amino acids such valine, leucine and isoleucine.

• Korean Journal of Agricultural Science
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• v.45 no.3
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• pp.379-384
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• 2018

In this study, we analyzed the amino acid contents of corn to provide basic data for promoting the use of proteins in livestock. The present study was done to examine the amino acid contents of the corn 'Gwangpyungok' grown in a natural field at the National Institute of Animal Science, Cheonan province, Korea, in 2016. Gwangpyungok, which is Korean corn cultivar, was used as the sample to provide basic data for promoting the use of proteins in livestock by analyzing the amino acid contents of each part of corn as a breed that is adaptable to the environment of Korea. The asparagine acid content was the highest in the leaf blade among the parts of corn, and the glutamic acid content was the highest in the corn ear, stem, leaf sheath, corn bract and inflorescence. The essential amino acids in the corn ear, leaf blade and inflorescence revealed that their contents were in the following order: leucine > phenylalanine > valine > threonine > lysine > isoleucine, and in the inflorescences and stem, leaf sheath and corn bract, their contents were in following order: leucine > valine > phenylalanine > threonine > lysine > isoleucine. Therefore, further research on the nutritional aspects of forage must be performed because livestock growth is influenced by the nutritive value of the various parts of forage.

• Korean Journal of Food Science and Technology
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• v.23 no.4
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• pp.405-409
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• 1991

The polysaccharide was predominantly composed of glucose (79.60%), galactose (9.68%), mannose(8.67%), fructose (1.96%;) and xylose (0.09%). Major amino acid in protein was consisted of cystein, aspartic acid, valine and glutamic acid. The tumor growth inhibition ratio of the polysaccharide against Sarcoma 180 was at highest level of 64.96%, when administerd at the concentration of 50 mg/kg and life prologation ratio showed 28.91% at the concentration of 50 mg/kg. The direct cytotoxic effect of polysaccharide was not observed in the tumor bearing mice with Sarcoma 180 in vitro.