• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.4
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• pp.293-296
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• 1979

The effects of temperature and salinity on tile rates of ammonia and amino nitrogen excretion, and oxygen consumption were measured for Crassostrea gigas. There was variability with temperature and salinity changes in both the rates of nitrogen excretion and the proportionality between ,ammonia and amino acids in the excreta, and also in the rates of oxygen consumption. Rates of nitrogen excretion and oxygen consumption were markedly decreased with increase in salinity, especially at high salinity-high temperature, whereas at low salinity-high temperature condition they were significantly increased. These changes are considered as the responses of physiological tolerances to the high temperature stress and the results of the metabolic temperature compensation at the low salinity-high temperature condition. Most of nitrogenous excretory products was ammonia, and large amounts of amino-nitrogen was excreted, and especially the rate of amino-nitrogen excretion was dominant at $32.5\%_{\circ}-22^{\circ}C$. The amounts of amino-nitrogen excreted by animals were decreased in the medium of high salinity and increased in the medium of low salinity through the experimental temperature. The atomic ratios of oxygen consumed to ammonia-nitrogen excreted (O: N ratio) was low at the low temperature $(15^{\circ}C)$, and was high at $22^{\circ}$ and $29^{\circ}C$ in the medium of 32.5 and $37.5\%_{\circ}$ but low in the low salinity $27.5\%_{\circ}$.

• Journal of Nutrition and Health
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• v.27 no.7
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• pp.699-708
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• 1994

This study aimed to verify the nutritional and curative effects of protein hydrolysate in rats with cysteamine-induced duodenal uncer. Duodenal ulcer rat model was established by intraperitoneal injections of cysteamine. Sprague-Dawley, female rats weighing approximately 200g were intraperitoneally injected twice cysteamine(13mg/100g BW) at intervals of 3h per day. This procedure was repeated 3$\times$at intervals of 3d. Animals fed on 10% casein diet for infection periods. After last injection, 4 kinds of diets(10% casein, 20% casein, 10% casein hydrolysate, 20% casein hydrolysate) were given. Gastric montility, trypsin activity in gastrointestinal content, retention rate of nitrogen, plasma total protein, albumin, amino-N, urinary urea nitrogen, creatinine and hydroxyproline were analyzed for nutritional effects of dietary nitrogen levels(10%, 20%) and sources(casein, casein hydrolysate). In duodenal ulcer rat model, there was no differences between 20% casein diet and 20% casein hydrolysate in the view of severeness of ulcer, gastric emptying rate, serum total protein, serum albumin, plasma $\alpha$-amino-N, UUN, creatinine excretion, GFR, nitrogen retention. On the other hand, rats on 10% casein hydrolysate diet group had more curative effect of the ulcer, higher plasma albumin concentration and nitrogen retention than 10% casein diet group. The casein hydrolysate diet group was lower trypsin activity in small intestinal content than the casein diet group, at both nitrogen levels(10%, 20%). The results suggest that protein hydrolysate be applied in diet therapy for the patients with gastrointestinal ulcer.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.4
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• pp.619-622
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• 1993

Rumen bacterial amino acids in sheep on urea diet were monitored to assess a possible change in amino acid synthesis as a long term response to high rumen ammonia environment. A sheep was fed a semipurified diet with soybean meal, followed by a diet with urea as a main nitrogen source. Mixed rumen bacteria were harvested from ruminal fluid taken 3 h after feeding (twice in soybean meal feeding and 6 times in urea feeding) and fractionated as cell wall, proteins and protein-free cell supernatant of monitor amino acids in each fraction. Ruminal ammonia concentration at the sampling ranged from 5.7 to 39.5 mgN/dl. Cell wall and protein fractions of mixed rumen bacteria were stable in their amino acid composition regardless of nitrogen sources of diet and the feeding duration. However, protein-free cell supernatant fraction showed a higher alanine proportion with urea feeding (18.6 and 28.2 molar % of alanine for samples from sheep fed soybean meal and urea, respectively) and its duration (20.6 and 32.9 molar % for samples from sheep on urea diet for 1 and 65 days, respectively). Total free amino acid level of bacteria was depressed in the initial period of urea feeding but restored on 65th day of the feeding. These results suggest that an alanine synthesizing system may develop in rumen bacteria as urea feeding becomes longer.

• Journal of the Korean Society of Food Culture
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• v.31 no.4
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• pp.348-356
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• 2016

The purpose of this study was to investigate the chemical contents (sugar, nitrogen, and amino acids) and sensory characteristics of traditional soy sauce according to three different methods. The samples were taken from four different periods (0, 20, 40, and 60 days after fermentation). Total sugar contents increased in all groups according to ripening period, and Gyupjang (G) showed the highest sugar content among the groups. Total nitrogen and amino acid contents of all groups increased after 60 days of ripening, and Gyupjang (G) and Gyupjang mixed with salt water (SG) had higher total nitrogen content compared to Chungjang (S) at the same period. The results from the sensory evaluation show that preferable sensory characteristics, such as color preferences, sweetness, umami taste, and overall preference, were significantly higher in Gyupjang (G) and Gyupjang mixed with salt water (SG) than in Chungjang (S). Preferable sensory characteristics had significantly high positive correlation with most amino acids, total nitrogen, and sugar contents, except for glutamine. Based on the significant difference in preferable sensory characteristics between Gyupjang mixed with salt water (SG) and Chungjang (S), Gyupjang mixed with salt water (SG) can be used to improve sensory characteristics. This research implies that adding salt water during the manufacturing Gyupjang process is advisable to yield high quality soy sauce.

• Microbiology and Biotechnology Letters
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• v.15 no.6
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• pp.369-374
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• 1987

A bacterium which grows on D-$\alpha$-Amino-$\varepsilon$-Caprolactam as sole carbon, energy and nitrogen source was isolated from the sludge of industrial areas in Taegu, and identified as Alcaligenes eutrophus. The optimum pH, temperature and concentration of D-$\alpha$-Amino-$\varepsilon$-Caprolactam for the growth were 6.0, 3$0^{\circ}C$ and 0.2% respectively. The bacteria could utilize glucose and fructose as a carbon source, and utilize ammonium chloride, ammonium nitrate, ammonium sulfate and sodium nitrate as a nitrogen source, and utilize L-Iysine and L-glutamate as a carbon and nitrogen source. It was found with thin layer chromatography and polarimeter that D-$\alpha$-Amino-$\varepsilon$-Caprolactam was converted to L-Iysine by the cell-free extracts of Alcaligenes eutrophus A52.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.4
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• pp.403-409
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• 1995

A growth experiment was conducted to evaluate the nutritivie values of supplemental lysine and methionine in broiler chicks. Two types of L-lysine, liquid and powder type, and DL-methionine were added to the diets at different levels of dietary protein with two growth phases, 0-3 weeks and 4-6 weeks named starter and grower, respectively. Six hundred seventy two chicks were allotted in 14 treatments; 3 controls by dietary CP level (starter-grower) with CP 23-21%, CP 21-19% and CP 20-18, 8 groups of liquid and powder lysine supplementation of 0.1, 0.2, 0.3 and 0.4%, and 3 groups of lysine and methionine supplementation. Body weight, feed intake, and excreta were measured and analyzed to determine growth performance, amino acid digestibilities, and the quantity of excreted nitrogen in feces. Chicks fed CP 23-20 with 3,200 ME kcal showed significantly better growth performance than those fed CP 21-18 for 6 weeks. The supplementation of 0.2% of either type of lysine to CP 21-19 diet improved weight gain and feed efficiecy to the extent that CP 23-21 diet was fed. Physical type of lysine did not affect chick's growth and amino acid digestibilities of the diets. The level of CP in the diet significantly affected nitrogen excretion in feces. Supplementation of lysine and methionine to CP 21-18 diet reduced fecal nitrogen by 10% compared to CP 23-21 diet. It was confirmed that 0.2% of supplemental lysine to the broiler diet spared the dietary protein by 3%, and also reduced nitrogen excretion in feces by 10%.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.403-408
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• 1999

This study was conducted to investigate chemical properties, quality stability and utilization of approved sardine surimi(ASS) which is developed our laboratory. The product yield of the ASS was about 3 times higher than that of usual sardine surimi(SS). The proper addition concentration of sodium bicarbonate was 0.1% for the neutralization of the ASS. The content of salt soluble protein nitrogen in the ASS was about the half of that in the SS, while the content of water soluble protein nitrogen was 2.4 times higher in ASS. The total amount of free amino acids in the ASS was about 11 times higher than that of the SS. Predominant free amino acids in the ASS were histidine, taurine, glutamic acid and alanine, and those four amino acids occupied 94% of total amount of free amino acids. During cold storage at 21oC for 6 months, the quality of ASS was more stable than that of SS in judging from changes of water soluble and salt soluble protein nitrogen, AV and POV. Quality of fish burger, fish sausage and fried fish paste processed in accordance with commercial processing preparation using the ASS or SS exclusively and mixtures which other white meat fish surimi(alaska pollack, hair tail and sole) were proportionallly added to each of two types of sardine meat were evaluated. In case of fish burger, the product processed from the ASS only were superior.

• Korean Journal of Environmental Agriculture
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• v.38 no.4
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• pp.262-268
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• 2019

BACKGROUND: To investigate mineralization characteristics of organic resources in the soil, five materials (rice straw, cow manure sawdust compost, microorganism compost, mixed oil-cake, and amino acid fertilizer) were treated according to the nitrogen content, and an indoor incubation experiment was conducted for 128 days. The results of this analysis were applied to determine the nitrogen mineralization pattern of these organic resources. METHODS AND RESULTS: During the constant temperature incubation period, the nitrogen net mineralization rate of the organic resources was the highest in the amino acid fertilizer with the highest nitrogen content, and the lowest in the rice straw with the lowest nitrogen content. A positive correlation (0.96) was observed between the potential nitrogen mineralization rate and total nitrogen content. The mineralization rate constant, k, was negatively correlated with the organic matter (-0.96) and carbon content (-0.97). The nitrogen mineralization rate during the first cropping season, as estimated by the model, was 6.6%, 11.6%, 30.9%, 70.7%, and 81.0% for the rice straw, the cow manure sawdust compost, the microorganism compost, the mixed oil-cake, and the amino acid fertilizer, respectively. CONCLUSION: The nitrogen mineralization rate varies depending on the type of organic resources or the nitrogen content; thus, it can be used as an index for determining the nitrogen supply characteristics of the organic resource. Organic resources such as compost with low nitrogen content or those undergoing fermentation contain organic nitrogen. Organic nitrogen is stabilized during the composting process. Therefore, as the nitrogen mineralization rate of these resources is lower than that of non-fermented organic resources, it is desirable to use the fermented organic materials only to improve soil physical properties rather than to supply nutrients for the required amount of fertilizer.

• Fisheries and Aquatic Sciences
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• v.4 no.3
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• pp.144-149
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• 2001

In other to establish the exact determination method of amino nitrogen (AN) in salt-fermented fish sauces, we determined the AN in fish sauces according to the measuring methods and also investigated the main factors influencing on determination method of AN. AN in salt-fermented anchovy sauce increased linearly as fermentation progressed, and was shown the highest amount measuring by the Formol method, followed by the trinitrobenzene sulfonic acid (TNBS) method and the Copper-salt method. AN concentration in anchovy sauces fermented for 12 months was $88.2\%$ and $77.6\%$ for the TNBS method and the Copper-salt method, respectively, on the basis of Formol method. The ratio of AN/total nitrogen (TN) in anchovy sauce fermented for 12 months was higher than that in commercial anchovy sauces. The determination of AN in anchovy sauce by the TNBS method was not affected by salt concentration, and slightly affected by heating. The effect of MSG on AN contents by Copper-salt method was shown higher than those by the Formol method and the TNBS method. The TNBS method was adaptable to measure the content of AN in fish sauce by this study.