• Analytical Science and Technology
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• v.11 no.6
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• pp.429-435
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• 1998

Free and glycine conjugated bile acids were detected fluoromatrically in high-performance liquid chromatography after derivatization with dansyl cadaverine. The coupling agent, diethyl phosphorocyanidate was used to form the amide bond between dansyl cadaverine and analytes. The dansyl derivatives of 8 bile acids were separated successfully on Cosmosil ODS column by using linear gradient elution of 20% MeOH-water/$CH_3CN$. The detection limits of cholic acid was reached 10 pg(S/N=5) per $1{\mu}l$ of injected volume. This new derivatization method would be applicable to detect the changes of bile acids in biological samples.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.2
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• pp.117-122
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• 1982

Abalone, Haliotis diversicolor japonica, is one of the most palatable sea foods in Jeju-Do, Korea : however relatively little is known about the characteristics of its taste. This study was undertaken to establish the basic data for evaluating the taste compounds in the extract of abalone including nucleotides and their related compounds, free amino acids, trimethylamine oxide, trimethylamine and total creatinine. The amount of AMP was $2.21{\mu}mole/g$ while IMP and inosine was trace in content. In the extracts, taurine, arginine and glycine were abundant holding $39.9\%,\;25.4\%,\;14.0\%$ of total free amino acids content respectively, but tyrosine and phenylalanine was trace in content. TMAO, TMA and total creatinine were poor in content marking $5.4mg\%,\;1.0mg\%\;and\;5.0mg\%$. It was presumed that the characteristic flavor of abalone was mainely attributed to free amino acids. Organic acids, nucleotides and their related compounds played auxiliary role in the characteristic flavor of abalone.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.4
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• pp.333-338
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• 1985

In this experiment, the contents of free amino acids, and nucleotides and their related compounds of dried cod products were analysed by amino acid autoanalyzer and HPLC. Proline, histidine, lysine and alanine were dominant amino acids in raw extracts, having $65.4\%$ of total free amino acid contents, but the contents of aspartic acid, serine, isoleucine and phenylalanine were low, and methionine, tyrosine and arginine were detected in trace amount. In free amino acid composition of dried products, abundant amino acids were glycine, histidine, lysine, proline and alanine. Such amino acid as aspartic acid, methionine, tyrosine and phenylalanine were poor. In extracts of storage sample, most free amino acids were increased in both sun dried products and hot air dried products, and glycine, histidine, lysine, proline and alanine were abundant amino acid, such amino acid as methionine, tyrosine and phenylalanine were poor. In raw cod, inosine and IMP were dominant contents which 18.5, $10.0{\mu}mole/g$ on dry base, respectively, but the contents of ATP, ADP, hypoxanthine and AMP were detected less than $3.2{\mu}mole/g$. ATP and ADP were decreased while IMP, inosine and hypoxanthine were increased during drying and storage of cod.

• Journal of the Korean Society of Food Culture
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• v.13 no.2
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• pp.91-96
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• 1998

This study was conducted to investigate the constituents of pumpkin and sweet-pumpkin. Moisture content of pumpkin was higher than that of sweet-pumpkin, but the other proximate constituents were lower. The major free amino acids were aspartic acid, threonine and cystine in pumpkin and cystine, arginine and tyrosine in sweet-pumpkin. Non-volatile organic acid of sweet-pumpkin was higher than that of pumpkin. Crude fat content of pumpkin and sweet-pumpkin were 0.33% and 0.48%. The major fatty acids were palmitic acid, linolenic acid and linoleic acid in pumpkin and oleic acid, linoleic acid and palmitic acid in sweet-pumpkin. The content of unsaturated fatty acid was 52.3%, 71.5% in pumpkin and sweet-pumpkin, respectively. The contents of minerals, vitamin C and carotenoid in sweet-pumpkin were higher than those of pumpkin.

• Analytical Science and Technology
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• v.8 no.3
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• pp.229-236
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• 1995

Multiple-step gradient method was used for the analysis of free amino acids in physiological fluids by high-performance liquid chromatography with diode array detector on the Amino Quant $C_{18}$ column under the condition of pH 7.2 of buffer solutions. Plasma samples of normal Korean people and abnormal Korean people who have schizophrenia were subjected to derivatization with o-phthalaldehyde in the presence of 3-mercaptopropionic acid. Quantitative analysis of amino acids in physiological fluids by internal standard method gave highly reproducible results within a relative standard deviation of less than 2~6%. And amino acids amounts of physiological fluids of Korean people gave some different results from those of foreigners. There was large differences in tyrosine amount between normal and abnormal man.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.403-410
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• 1994

Changes in physical and chemical characteristics of industry-type kochujang were investigated during 105 days of storage at $37^{\circ}C$. Reducing sugar content of kochujang decreased rapidly up to the 15th day of storage and then decreased slowly thereafter. Total free amino acid contents decreased by 22.3% after 60 days and by 35% after 90 days of storage. The activities of amylase and protease did not show any significant changes, however, the activity of neutral protease increased slightly. The moisture content and water activity of the kochujang decreased linealy during storage and the correlation coefficient between the moisture content and water activity showed 0.964. Apparent viscosity of kochujang increased with an increase in storage time. It was found that water activity was more responsible for the increase of apparent viscosity than water content.

• Food Science and Preservation
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• v.14 no.5
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• pp.492-496
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• 2007

This study analyzed the sugar, amino acid, and mineral content of Angelica dahurica leaves to explore the physiology of the plant and to examine whether the loaves might be useful in food production. A. dahurica leaves contained moisture 76.30%, carbohydrate 7.58%, crude protein 4.01% crude ash 7.87% and 4.23% crude fat (all w/w). The content of reducing sugar in leaf was 1,687.10 mg/100 g. The total amount of free sugar was 57.30 mg/100 g, including 24.75 mg/100 g fructose, 23.95 mg/100g glucose, and 8.60 mg/100 g maltose. Total hydrolyzed amino acids were 139.25 mg/100 g. Total free amino acids were 215.99 mg/100 g, and that of alanine (61.52 mg/100 g) was highest. Total amino acid derivatives were 101.39 mg/100 g, and, of these materials ${\gamma}-aminoisobutyric$ acid was highest at 78.26 mg/100 g. In the When minerals were analyzed, the content of K was the highest (2,135.03 mg/100 g), followed by 916.47 mg/100 g for Ca.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.1
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• pp.25-31
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• 2000

In order to investigate the composition, seasonal and regional variation of extractive nitrogenous components in the raw anchovy (Engraulis japonica) harvested from June 1991 to June 1992 at Nam-hae and Ki-jang in the southern coast of Korea, the contents of extractive nitrogen (EN), free amino acids (FAA), oligopeptides (OP), ATP and its related compounds (ARC), quaternary ammonium bases, and guanidino compounds were measured. The EN contents of raw anchovy were $444{\~}773\;mg/100\;g$. Thirty-four kinds of FAA were found and their total amount were $1,049{\~}2,079\;mg/100\;g$. Histidine, taurine, alanine, leucine and glutamic acid were the major free amino acids in the anchovy extracts. The amount of ARC was average $5.02\;{\mu}mol/g$, and IMP was the major compound among them, who and creatine contents in the extracts or raw anchovy were average 164 and 229 mg/100 g, respectively. The contents of glycinebetaine,${\brta}-alaninebetaine,\;{\gamma}-burobetaine$, homarine, TMA, and creatinine were extremely small. As for the regional and seasonal disparities, the Nam-hae samples contained more EN, FAA, OP, betaines and creatine than the Ki-jang samples. On the other hand the Ki-jang samples contained more ARC and TMAO. The spring samples contained more EN, FAA, OP, ARC and betaines than the autumn samples. On the other side the autumn samples contained more TAMO and creatine.

• Food Science and Preservation
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• v.12 no.2
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• pp.156-160
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• 2005

To obtain basic data utilizing chestnuts as a raw food material, proximate analysis was conducted. Chemical component of chestnut flesh were $63.60\%$ moisture, $118\%$ ash, $3.02\%$ crude protein, $0.615\%$ crude fat, $1.21\%$ crude fiber, and $30.37\%$ nitrogen free extract, respectively. The weight ratio of tegmen, seed coat and flesh of chestnut sample were 17.05, 14.9, and $68.05\%$, respectively. The total amino acid contents of flesh and seed coat were $2,994\;mg\%$ and $1,450\;mg\%$, respectively. The total amount of free amino acids was less than that of total amino acids. As results of mineral analysis, the content of K was higher than that of any other minerals. The contents of maltose and sucrose were higher than those of fructose and glucose. The total polyphenol contents of tegmen, seed coat, fresh, leaf and bark were $9.56\;mg\%$, $0.047\;mg\%$, $0.23\;mg\%$, $15.44\;mg\%$ and $17.85\;mg\%$, respectively.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.511-517
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• 1988

Kimchi, a traditional vegitable fermented food in Korea, was prepared and fermented at $5^{\circ}C$ in order to analyze the taste and flavor compounds. Major flavor components were identified as dimethyl-disulfide, dimethyl-trisulfide, dipropyl-disulfide, 1-butane 1-isothiocyanate, diallyl-disulfide by GC and GC/MS. Some organic acids such as lactic acid and citric acid increased from 1.2mg/100g and 5.4mg/100g in the initial stage to 33.3mg/100g and 44.4mg/100g at the end of fermentation, respectively. Free amino acids in kimchi were found to play an important role for the taste. The contents of total free amino acid increased from 316.3mg/100g to 600mg/100g in the fermented kimchi and glutamic acid, alanine, valine, leucine, lysine and arginine were abundant in kimchi. The results of sensory evaluation showed that the taste of kimchi was closely related to the contents of non-volatile organic acid, free amino acid and pH.