• Food Quality and Culture
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• v.2 no.2
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• pp.89-96
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• 2008

In order to determine whether green tea tannin ameliorates abnormal arginine metabolism as the result of excessive arginine, we have assessed the effects of the administration of green tea tannin mixture in rats treated 30 days with 2% arginine. In the arginine-treated group, the level of guanidino compounds such as arginine (Arg), guanidinoacetic acid (GAA), creatinine (Cr), methylguanidine (MG) and guanidinosuccinic acid (GSA), nitric oxide, urea, protein and glucose increased significantly in the serum, urine and kidney, whereas the oxygen species-scavenging enzymes of kidney were reduced as compared with the non-arginine-treated group. By way of contrast, the administration of green tea tannin reduced blood urea nitrogen and serum creatinine, and reduced the urinary excretion of guanidinoacetic acid, creatinine, and $NO_2^-+NO_3^-$. The increased levels of urinary urea, protein and glucose in the arginine-treated group were also lowered by the administration of green tea tannin. In these groups, the activities of superoxide dismutase and catalase in the kidney were increased, thereby suggesting the involvement of radicals in the normalizing of kidney function. These results show that the abnormal renal function induced by the adminstration of excessive arginine in rats may be restored by treatment with green tea tannin.

• Fisheries and Aquatic Sciences
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• v.2 no.2
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• pp.135-141
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• 1999

In order to investigate the composition of extractive nitrogenous components in the diploid and the triploid oysters, Crassostrea gigas, cultured at the south coast of Korea, the whole edible part (whole body) was analyzed into extractive nitrogen, free amino acids, oligopeptides, ATP and its related compounds, quaternary ammonium bases, and guanidino compounds using specimens collected from April to May of 1992. The major free amino acids in the diploid and the triploid were taurine, proline, alanine, glycine, glutamic acid hypotaurine, glutamine, arginine, aspartic acid, and $\beta-alanine$. There was no conspicuous difference in the constituents of free amino acids between the diploid and the triploid. A lot of hypotaurine was detected in the diploid and the triploid of oyster and the contents of them were 107 mg and 123 mg/100g, respectively. The compounds, glycinebetaine, homarine and trigonelline were found in both the diploid and the triploid. Among them, glycinebetaine was the most prominent in all the samples. The amount of protein, glycogen, extractive nitrogen, oligopeptides, ATP and its related compounds, and free amino acids in the triploid was higher than that of the diploid (p<0.10)

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.954-961
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• 2002

Extracts of raw bloody clams, broughton's ribbed ark (Scaphrca broughtonii), subcrenated ark (S. subcrenata), and granulated ark (Tegillarca granosa), were analyzed and compared foe extractive nitrogen, free amino acids, combined amino acids, ATP and related compounds, quaternary ammonium bases, and guanidino compounds. The contents of extractive nitrogen in broughton's ribbed ark, subcrenated ark, and granulated ark were 479, 506, and 432 mg/100 g, respectively. Twenty-eight or twenty-nine types of free amino acids were detected in all three extracts, among which taurine, ${\beta}-alanine$, glutamic acid, and alanine were the major ones. The composition of the major extractive components such as free amino acids, combined amino acids, ATP and related compounds, TMAO, TMA, and creatine in the extracts were similar among the extracts, but their contents were different.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.274-279
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• 1995

Seasonal variation of the taste components such as free amino acids, nucleotides, quarternary ammonium bases, and guanidino compounds in warty sea squirt(S. clava) were determined bimonthly from April to October for its food quality contributed in Korean seafood dishes. Fifty to sixty two percentage of the extractable nitrogen was free amino acids, and mainely it composed of taurine, proline, glutamic acid, glycine and glycinebetaine. Among the various taste component, betaine's level was somewhat higher(11~15%) and nucleotides related compounds also followed(5~8%). Most of nitrogenous compounds in the extractives reached to a maximum value in June and AMP content was relatively higher than the other nucleotides. The major organic acids were composed of succinic acid, malic acid, lactic acid and pyroglutaric acid in S. clava. The result of omission test suggested that the taste of S. clava is mainly attributed to free amino acids, betaines, nucleotides and non-volatile organic acid in order.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.13-19
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• 1999

In order to investigate the composition and the actual status of extractive nitrogenous compounds in the fresh 'Gae-bul' (echiuroid), a kind of echiurida (Urechis unicinctus), the extract was analyzed separately into extractive nitrogen, free amino acids (FAAs), oligopeptides, nucleotides and related compounds, quaternary ammonium bases, and guanidino compounds, using specimens collected at fish market in April 1988. The extractive nitrogen of echiuroid was $601{\sim}610mg/100g$. Thirty-two kinds of FAAs were found, and the total of them in it was $2,437{\sim}2,609\;mg$. Glycine, alanine, taurine, and serine were the major FAAs in the echiuroid extracts. The large amount of glycine $(1,075{\sim}1,171mg)$ was noted in the extract. The sum of ATP and its related compounds was $3.04{\sim}3.12\;{\mu}mol/g$, and predominant compound was the AMP. Besides, CTP, GTP, UTP and their related compounds were also detected, and the total amount of them was $1.92{\sim}3.74\;{\mu}mol/g$. The lower homarine, trigonelline, TMAO, TMA, and creatine were detected in the extracts. The extractive nitrogenous constituents of medium size and large size echiuroid were almost the same level each other. The total nitrogens of the compounds analyzed for each samples accounted for more than 90% of the extractive nitrogen in this study.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.1
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• pp.51-63
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• 1996

In order to investigate the food quality of Korean chum salmon (Oncorhynchus keta) the composition of extractive nitrogenous components including the free amino acids, oligopeptides, nucleotides and related compounds, guanidino compounds, and quaternary ammonium bases were analyzed. The extractive nitrogen from the muscle ranged from 478 to 649 mg/100 g with little discrepancies by sex, sampling seasons and areas. The large amount of anserine was noted with fairly low level of taurine, alanine, glycine, glutamic acid and lysine in each extract. After Hydrolysis of the entracts remarkable increases were found in $\pi-methylhistidine,\;\beta-alanine$ from anserine and carnosine. The sum of nucleotides and related compounds of the muscle was $3.32\~9.22\;{\mu}mol/g$, and predominant compound was the inosine 5'-monophosphate. The lower glycinebetaine, $\beta-alaninebetaine$ and homarine were also found in some samples. The trimethylamine oxide content of the muscle was ranged from 107 to 148 mg, and the trimethylamine content was no move than 11 mg in all the collections. The concentrations of creatine in the muscle extracts ranged from 477 to 642 mg, and $8\~11mg$ for creatinine, respectively. The total nitrogens of the compounds analyzed for each samples accounted for more than $90\%$ of the extractive nitrogen in this study.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.2
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• pp.150-158
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• 1993

In order to investigate the content and seasonal variation of the extractive components including taste compounds, free amino acids, nucleotides and related compounds, quanternary ammonium bases, and guanidino compounds of ascidian collected from the south coast of Korea were determined bimonthy from April to October in 1990. The extractive nitrogen was composed of $60{\sim}62\%$ as free amino acids, $12{\sim}16\%$ as betaines, $5{\sim}9\%$ as nucleotides, and others as trimethylamine oxide(TMAO) and total creatinine. The muscle of ascidian was rich in such free amino acids as taurine, proline, glutamic acid, glycine and glycinebetaine. Most of nitrogenous compounds in the extractives showed a marked seasonal variation with a maximum in summer or autumn. AMP content was relatively high among nucleotides. Succinic acid, malic acid, lactic acid and pyroglutaric acid were the major organic acids in ascidian. The results of omission test suggested that the taste of ascidian is attributed to mainly free amino acid, betaines, nucleotides and nonvolatile organic acid in order.

• Korean Journal of Food Science and Technology
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• v.27 no.4
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• pp.471-477
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• 1995

Extractive nitrogen, free amino acids, oligopeptides, nucleotides and related compounds, quaternary ammonium bases, and guanidino compounds were analyzed to evaluate quality of anchovy sauce. The commercial products contained low proximate composition, extractive nitrogen and other extractive components, than the experimentally prepared anchovy sauce. Both samples, commercial products and experimentally prepared anchovy sauce, were rich in free amino acids, such as glutamic acid, leucine, alanine, lysine, and aspartic acid. The extractive nitrogenous components which consist of total nucleotides and related compounds, total free amino acids, methionine, isoleucine, valine, taurine, tyrosine, histidine, leucine, aspartic acid, cystine, and lysine, showed significant correlation(p<0.01) with extractive nitrogen. Possibly, seven kinds of free amino acids such as methionine, isoleucine, valine, taurine, tyrosine, histidine, and leucine, might be recommend as quality indices of standardization for anchovy sauce.

• 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.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1111-1118
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• 1996

The extracts of toha, a kind of freshwater shrimp (Caridina denticulata denticulata) being cultivated in Naju district, Chonnam of Korea and jeotsaeu, a kind of seawater shrimp (Acetes japonicus) being caught in Shinan district, Chonnam of Korea, were analyzed for the taste constituents-extractive nitrogen, free amino acids, oligopeptides, nucleotides and related compounds, quaternary ammonium bases, and guanidino compounds-using specimens collected from December in 1994 to November in 1995. The content of extractive nitrogen. free amino acids, oligopeptides, nucleotides and related compounds in toha extract was higher than that in jeotsaeu extract. On the contrary, the amount of homarine, trimethylamine oxide and trimethlamine in toha extract was lower than that in jeotsaeu extract. But in case of creatine and creatine both species showed almost the same level. Arginine, lysine, glutamine, glutamic acid, phenylalanine, leucine, alanine, asparagine and glycine were the major amino acids in toha extract, while arginine, glutamic acid, proline, glutamine, lysine, leucine, glycine, alanine and taurine were the major amino acids in jeotsaeu extract. Methionine, glutamine, valine were almost the same level between the two species. As for nucleotides and related compound, AMP was the principal constituent in toha extract, and inosine was the principal constituent in jeotsaeu extract. In conclusion, the content of major nitrogenous constituents in toha extract was more abundant than that in jeotsaeu extract. So toha was more excellent raw material than jeotsaeu.