• Journal of Korean Society on Water Environment
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• v.30 no.5
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• pp.503-511
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• 2014

The temporal and spatial analyses of total nitrogen (TN) fractionation were conducted in order to understand 1) total nitrogen components in streams and 2) their patterns in rainy and dry seasons. The result showed that the concentration of nitrogen components in stream water was lower in non-urban area and getting higher in urban area. Dissolved total nitrogen (DTN) was 95~97.7% of total nitrogen in streams, and the proportion of dissolved organic nitrogen (DON) and ammonia nitrogen ($NH_3-N$) was higher with increasing urban area. The concentration of total nitrogen and nitrate nitrogen ($NO_3-N$) were highest in winter among four seasons. The result was showed that concentration of $NH_3-N$ was same variation as concentrations of TN and $NO_3-N$ in urban-rural complex and urban areas, except rural areas. During rainy season, concentrations of particulate organic nitrogen (PON) and $NH_3-N$ increased in rural areas and decreased in both urban-rural complex and urban areas. Correlation between total nitrogen components and land uses was positively correlated with site > paddy, and negatively correlated with forest. The variation of total nitrogen concentration was determined by $NO_3-N$ in non-urban areas, by $NO_3-N$ and $NH_3-N$ in urban-rural complex and by $NH_3-N$ in the urban areas.

• Journal of the Korean Society of Tobacco Science
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• v.3 no.1
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• pp.20-24
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• 1981

This experiment was carried out to determine the relationships between maturity and content of the chemical components in flue-cured tobacco. The results were as follows : 1) Among the chemical components, the contents of total nitrogen, ammonia nitrogen, total alkaloids, nicotine, total volatile base, petroleum-ether extract, crude fiber, crude ash, water soluble ash, and chlorine decreased significantly, and those of total sugar, reducing sugar, and starch increased as leaf maturity progressed until the stage of ripeness, but, afterwards, a reverse tendency appeared. 2) There was a significant relationship between maturity and the contents of chemical components, such as total nitrogen, protein nitrogen, ammonia nitrogen, total volatile base, and the correlation coefficients of them were -0.743, -0.789, -0.797, and -0.642, respectively.

• Korean journal of food and cookery science
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• v.6 no.2
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• pp.85-96
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• 1990

Globefish, Fugu xanthopterus, known to have a severe toxin, is one of the favorite food in Korea and Japan when the toxic part is removed. In this paper, the effect of cooking on the composition of nitrogenous components in the extractives from globefish cooked investigated and the changes of the taste compounds originated from the nitrogenous components in the extractives were discussed. When the sample fish was analysed for general composition, drip amount and pH by the different methods of thawing, the method effective method was the running water thawing. Total nitrogen content in raw globefish and the frozen globefish was not different, and the nitrogen content was increased with the heat treatment. It seemed that the nitrogen content was higher in the extract from the boiled globefish than that of the steamed globefish. Taurine, lysine, glycine and alanine were occupied about 70% of the total free amino acids. Total free amino acid content was higher in the extracts from the frozen sample than those from the raw sample. The amount of free amino acids was increased when the globefish soup cooked under the direct-heat cooking than in the microwave oven-heat cooking. Among nucleotides in the extracts from the thawed and cooked fishes, IMP and inosine contents were increased, and the both components were decreased with the heating time and by the heating method. Tne content of total creatinine-nitrogen were 50% of the total nitrogen content of the extracts, but the concentration of glycinebetaine, TMA and TMAO were only a few amounts. It could be concluded that total creatinine components, including free amino acids such as taurine, lysine, glycine and alanine, and IMP might be the important components contributing to the taste of the cooked globefish.

• Korean journal of food and cookery science
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• v.12 no.3
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• pp.273-278
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• 1996

To investigate the main components of Korean traditional soy sauce for its typical taste, we compare the physicochemical properties of Korean traditional soy sauce and commercial soy sauce. The physicochemical analysis revealed that each components showed significant difference between Korean traditional soy sauce and commercial soy sauce. The significant characters for discrimination between Korean traditional soy sauce and commercial soy sauce were salt content, ammonia nitrogen content and total acidity (R$^2$=0.99). The components of Korean traditional soy sauce divided into 3 clusters, and each group is characterized as formol nitrogen, salt and total nitrogen content by cluster analysis. Main amino acids of Korean traditional soy sauce were alanine, glutamic acid, leucine and valine.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.4
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• pp.323-327
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• 2002

Plant growth and the two components of respiration, growth and maintenance, were compared between low and high nitrogen applications in hydroponic culture on a high-yielding rice cultivar 'Takanari' (Oryza sativa L.). Grain yield decreased by high nitrogen application, and thus this cultivar has low adaptability to nitrogen. Growth efficiency (GE) and net assimilation rate (NAR) were lower in the high-nitrogen plot. The maintenance coefficient (m) and growth coefficient (g) of dark respiration were 0.0111 $d^{-1}$ and 0.196 in the low-nitrogen plot and 0.0166 $d^{-1}$ and 0.237 in the high-nitrogen plot, respectively. Thus, high nitrogen application increased both g and m. Calculated $R_m$ (maintenance respiration rate) was 70 and 90% of total respiration rate at heading, respectively. The significance of nitrogen adaptability and g was discussed.

• Journal of the Korean Applied Science and Technology
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• v.25 no.3
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• pp.355-362
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• 2008

One of the popular domestic sewage treatment process (called step feed oxic-anoxic-oxic process) for nitrogen removal was analyzed in this study by theoretical analysis based on the nitrification and denitrification reaction. Total nitrogen removal efficiency was suggested by considering influent qualities(i.e., ammonia, nitrite, nitrate, alkalinity, and COD). Total nitrogen removal efficiency depends on r (influent allocation ratio). In the case that all influent components are enough, the total nitrogen removal follows equation 100-b/(1+b), when r is 1/(1+b). Finally, it can be concluded that step feed oxic-anoxic-oxic process could be effective for nitrogen removal.

• Journal of Environmental Health Sciences
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• v.30 no.1
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• pp.22-28
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• 2004

This study was performed to investigate the changes of amino nitrogen, total amino acids, free amino acids, and color of Korean traditional soy sauce (kan-jang) during the ripening and storage for 12 months and the characteristics of the changes. All of the preparation methods for soy sauce followed the recommendations of the Korea Food Research Institute. The components of soy sauce were analyzed at 0,6, and 12 months. The contents of amino nitrogen of soy sauce were significantly higher than that of soybeans or meju (soybean cakes) at the initial stage of storage (p<0.05), and decreased during the storage. The content of total amino acids of soybean sauce was significantly lower than that of soybeans, and the content of free amino acids was higher than that of soybeans (p<0.05). The contents of total and free amino acids decreased in soy sauce after 12 months of storage (p<0.05). The composition of total and free amino acids and their ratios of soy sauce were changed during the storage. The ratios of free to total amino acids of soybeans, meju, and soy sauce were 0.8％, 17.3％, and 53.1-59.8％, respectively. Glutamic acid, which represents the savory taste, was detected the most abundantly in soy sauce during the storage. The ratios of free to total amino acids of glutamic acid were 42.9-59.5％ in soy sauce. Lightness of Hunter color of soy sauce decreased over time (p<0.05). This study indicates that the ratios of free to total amino acids of soy sauce were much higher than those of soybeans, although its contents of total amino acids were much lower than those of soybeans. This study also indicates that this comes from the preparation and fermentation of meju. It was suspected that the organoleptic characteristics of soy sauce derived from the amino nitrogen, amino acids, and color might be inferior over 1 year of storage time. However, more detailed research should be conducted to interpretate this characteristics more accurately.

• Journal of Nutrition and Health
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• v.23 no.3
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• pp.179-186
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• 1990

Nitrogen(N) concentrations of human milk in various fractions, such as total, protein, nonprotein, whey protein and casein were determined at 2-3 days, 1, 2, 4, 6 and 12 weeks of postpartum. significant decreases in total N, nonprotein N, protein N, whey protein N and casein N were found with time postpartum. Total nitrogen decreased from 401mg/dl at 2-3 days to 211mg/dl at 12 week. Whey protein nitrogen was found to contribute to the total nitrogen decrease with time. The percentage of nonprotein nitrogen was 13% in colostrum and 17-18% in mature milk. The proportions of whey protein and casein nitrogen were 55:45 at 2-3 days and 34:66 at 12 week postpartum. These determinations will provide the basic information on the variability of nitrogen components as lactation proceed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.4
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• pp.237-240
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• 2000

This experiment was conducted to evaluate the effect of split application of nitrogen(N) on development of vascular bundle(VB) and yield components of rice. Two cultivars were used in this study; IR58, an indica type and Shinunbongbyeim a japonica type. The number and total cross sectional area of the VB in the peduncle and leaf blade were more and bigger in N split application than 100 percent basal fertilizer. Nitrogen split application at necknode differentiation stage increased the number and size of the VB. Nitrogen split application resulted in increased panicle number with application of N before transplanting and at tillering stage; increased spikelets number with N application at necknode differentiation stage; and increased spikelet fertility and 1000 grain weight with N application at necknode differentiation and heading stages. Grain yield increased 7-10% in N split as compared to all basal application. The total cross sectional area of VB in peduncle closely correlated with the number of spikelets per panicle. Nitrogen management can have an impact on spikelet differentiation through more and bigger VB and increase grain yield potential.

• Korean journal of applied entomology
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• v.9 no.1
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• pp.15-20
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• 1970

An investigation was carried out to know the relationship between resistance of rice varieties to blast disease and the chemical components, especially total nitrogen and total sugars, in the rice plants. The results sic summarized as follow: 1) The nitrogen contents in the resistant variety were less than those of susceptible one, and sugar contents were reversed. Accordingly, the C/N ratio in the resistant variety was higher than that obtained by susceptible one. 2) The free amino acids contents, especially, Glutamine, Valine, Leusine and Iso-leusine, in the resistant varieties were more than those of the susceptible varieties. 3) The starch synthetic activity of rice leaves in the resistant varieties was higher than that of susceptible one in fructose and glucose solutions, but it was reversed in sucrose solution. 4) When more nitrogen was dressed, the total nitrogen content of rice leaves was increased than the ordinary dressing. The rate of increase in nitrogen content in resistant variety was lower than those of the susceptible. The total sugar content of rice plants dressed more nitrogen was decreased at early tillering stage, but increased at maximum tillering stage. It seemed that the rate of increase of total sugar in the resistant variety was higher than those of the susceptible.