• Asian-Australasian Journal of Animal Sciences
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• v.30 no.8
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• pp.1168-1174
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• 2017

Objective: The aim of the study was to evaluate the effects of different nitrate levels (150, 300, 450, and 600 ppm $KNO_3$) on the volatile compounds and some other properties of pastırma. Methods: Pastırma samples were produced under the controlled condition and analyses of volatile compounds, and thiobarbituric acid reactive substances (TBARS) as an indicator of lipid oxidation, non-protein nitrogenous matter content as an indicator of proteolysis, color and residual nitrite were carried out on the final product. The profile of volatile compounds of pastırma samples was analyzed by gas chromatography/mass spectrometry using a solid phase microextraction. Results: Nitrate level had a significant effect on pH value (p<0.05) and a very significant effect on TBARS value (p<0.01). No significant differences were determined in terms of $a_w$ value, non-protein nitrogenous substance content, color and residual nitrite between pastırma groups produced by using different nitrate levels. Nitrate level had a significant (p<0.05) or a very significant (p<0.01) effect on some volatile compounds. It was determined that the amounts and counts of volatile compounds were lower in the 450 and especially 600 ppm nitrate levels than 150 and 300 ppm nitrate levels (p<0.05). While the use of 600 ppm nitrate did not cause an increase in residual nitrite levels, the use of 150 ppm nitrate did not negatively affect the color of pastırma. However, the levels of volatile compounds decreased with an increasing level of nitrate. Conclusion: The use of 600 ppm nitrate is not a risk in terms of residual nitrite in pastırma produced under controlled condition, however, this level is not suitable due to decrease in the amount of volatile compounds.

• Fisheries and Aquatic Sciences
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• v.8 no.2
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• pp.43-50
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• 2005

We evaluated the nutritional composition of the siphon of the surf clam Tresus keenae in regard to the presence of nitrogenous [amino acids, nucleotides and their related compounds, total creatinine, betaine, trimethylamine oxide (TMAO), and trimethylamine (TMA)] and non­nitrogenous compounds (sugars and organic acids), lipid fatty-acid composition, and occurrence of minerals. The content of total free amino acids was 660.27 $\pm$ 7.94 mg/100 g, and the predominant amino acids were arginine, alanine, sarcosine, glycine, and glutamic acid. These amino acids accounted for $71\;\%$ of the total free amino acids. Among the nucleotides and their related compounds, inosine was the major component and comprised 40.38 $\pm$ 0.02 mg/100 g. Free amino acids were the largest contributor to total extracted nitrogen, comprising $49.94\%$, followed by total creatinine, betaine, nucleotides, and ammonia; the contribution of TMAO and TMA was small. For the non-nitrogenous compounds, malic acid, propionic acid, and succinic acid comprised the major portion of the ten kinds of organic acids detected, and the sugars found were glucose, maltose, and arabinose, which were estimated to be $147.0\pm7.15,\;34.45\pm1.09,\;and\;1.21\pm0.02\;mg/100\;g,$ respectively. The predominant minerals were Na and K, which comprised $11.43\pm1.06\;and\;9.46\pm1.02\;mg/100\;g,$ respectively. The major fatty acids were C22:6, C20:5, C23:0, C18:3, and C16:0 in the lipid fractions. The 23:0 level of glycolipid (GL) was the highest of any other lipid fraction. The amount of total polyunsaturated fatty acids (PUFA) in the lipid fractions was higher, ranging from $58.22\%\;in\;GL\;to\;77.1\%$ in phospholipid (PL), compared to the saturated and monounsaturated fatty acids. Of the n-3 fatty acids, C20:5 and C22:6 contributed $35.30-64.44\%$ of PUFA in the lipid fractions. The ratios of n-3 to n-6 PUFA in total lipid (TL), neutral lipid (NL), PL, and GL were 4.35, 4.26, 6.69, and 2.04, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.12 no.2
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• pp.91-97
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• 1979

1. Nitrogenous compounds of-organic materials as nitrogen sources for Korean ginseng were characterized according to their solubility and chemical forms. 2. The extractable fractionation was as follows : Yakto group : non-extractable N > acid hydrolyzable N > acid nonhydrolyzable N > water sol. N, Litter group : acid hydrolyzable N > non-extractable N > water sol. N > acid non-hydrolyzable N, Bone meal : acid hydrolyzable N > water sol. N > acid non-hydrolyzable N. 3. Nitrogenous compounds in the water sol. fraction were : Yakto group and Litter group : humus N > amino acid N > nitrate N (recognized only in Yakto group) > ammonia N > hexosamine N > amide N, Bone meal : amino acid N > humus N > ammonia N > amide N. And nitrogenous compounds in the acid hydrolyzable fraction were : amino acid N > humus N ${\simeq}$ ammonia N > hexosamine N. 4. Availability was discussed about the major nitrogenous compounds (amino acid, humus and inorganic N) and the solubility.

• The Korean Journal of Food & Health Convergence
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• v.6 no.6
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• pp.1-7
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• 2020

We compared the fermentation of 0 to 4 weeks by manufacturing a rapid low salt-fermented seahorse with a commercial Protamex added to the functional food, Hippocampus abdominalis. We studied amino acid composition, content and major amino acids related to flavor during the fermentation process of salt-fermented seahorse. In the enzyme-free group, it showed little change in the content of non-protein nitrogenous compounds, the content of amino acids and degree of hydrolysis. The Protamex enzyme treatment group was rapidly hydrolyzed in one week of ripening, resulting in increased non-protein nitrogenous compounds content, amino acid content and degree of hydrolysis, and minimal changes in the four weeks. The total amino acid contents ratio showed the highest content of glutamic acid in the enzyme additive group, glycine, alanine, which indicates sweet taste, and serine, the content of glycine, alanine, serine, and lysine, indicating sweet taste, has increased significantly over the enzyme-free group. Twenty species of free amino acid in the four-week of salt-fermented seahorse were detected. It detected 43.0% (6 species) in the enzyme-free group and 63.96% (7 species) in the enzyme additive group.

• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.1
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• pp.7-15
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• 1993

Nitrogenous and non structural carbohydrate compounds in the remaining tissues of 10 weeks old alfalfa (Medicago sativa L.) grown in hydroponic culture, were analysed during 24 days of regrowth following shoot removal. The dry weights of the remaining organs were not significantly changed for 10 days following shoot removal. Compared with uncut plants, defoliation drastically depressed root growth, in particular that of taproot. During 6 days of regrowth, nitrogen contents in all remaning organs significantly decreased. Nitrogen loss in this period was pronounced in root system. Nitrogen contents in each organ after 24 days of regrowth in defoliated plant were recovered completely or exceeded initial level. Amino acid-N was the most readily available form of nitrogen while protein-N was the largest storage pool. The tap root contained about 51.0% and 33.4%, respectively, of the total starch and total ethanol-soluble sugar contents. The starch content of tap roots initially exceeded 40.7 mg. plant$^{-1}$ (day 0), and then declined to the minimum level on day 14. This result clearly showed that the tap root is the major storage site for metabolizable nitrogen (protein-N and amino acid-N) and carbohydrate(starch), and that the degradation of these researves occur much actively in the early period of regrowth.

• Journal of Plant Biology
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• v.33 no.2
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• pp.119-126
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• 1990

The content of canavanine was measured and analyzed in leaves, roots and xylem exudate of Canavalia lneata. In non-nodulated plants, the cotyledons were removed after a week of sowing and the plants were grown for 3 weeks. The quantity of canavanine measured by canavanine specific-PCAF colorimetric assay was 9-10 $\mu$mol/g fresh wt. in leaves, 5-6 $\mu$mol/g fresh wt. in roots, and 0.3-0.5 $\mu$mol/ml in xylem exudate. When free amino acids of leaves, roots, and xylem exudate were analysed by HPLC, the relative proportion of asparagine plus glycine was the highest and canavanine was high secondarily. And the relative proportion of canavanine among total free amino acids was 30-35% in leaves and roots, and 12-13% in xylem exudate. In non-nodulated plants grown for 8 weeks, the canavanine content of each part was similar to that of 3-week-old plants. By the formation of nodules, the canavanine content of leaves, roots, xylem exudate, and nodules decreased apparently. In xylem exduate, the nitrogenous compounds were also analyzed. The relative contents of NO3-, free amino acids, and ureides(allantoin and allantoic acid) were 60-80%, 20-30%, and 5%, respectively. From these results, it can be assumed that canavanine is synthesized in the root of plant and nodulation affects the canavanine content. It is obvious that canavanine is considered one of the reduced-N forms transported via xylem.

• Journal of Korean Society of Forest Science
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• v.102 no.1
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• pp.129-135
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• 2013

Japanese larch (Larix leptolepis) has been extensively planted in Korea as a reforestation species but their supply has been a major bottleneck due to sporadic natural seed production. In this study, stem girdling was applied to 32-year-old grafted Japanese larches, resulting in significantly enhanced seed production compared to the controls. Stem girdling induced about 4 times higher cone production than that of controls in the Japanese larch seed orchard. Time-dependent metabolic alterations after girdling were investigated by stable isotope ratio mass spectrometer, HPLC, and GC-MS analysis. In girdled trees, the contents of total nitrogen, sucrose, and total free amino acids were significantly higher than the non-girdled trees at the flowering differentiation season (from July to August). Moreover, the numbers of female strobilus per tree were positively correlated with the contents of both total nitrogen (r=0.765, p<0.01) and total amino acids (r=0.802, p<0.01) in the bark being collected at the flowering differentiation time (August 20). Interestingly, the levels of various individual amino acids at the flowering differentiation times, such as aspartic acid, glutamic acid, glycine, serine, and cysteine, were also significantly correlated (p<0.05) with the numbers of strobilus, suggesting that those amino acids might be involved in the induction of female strobilus formation of Japanese larches.

• 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.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.1
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• pp.42-48
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• 2014

In this study, variations of the organic and nitrogenous compounds in wastewater were investigated in a single reactor with intermittent aeration. Over 90% of organic and nitrogen removals are accomplished with C/N ratio of 3 : 1 and 20/20 min of aeration/non-aeration period. Longer non-aeration period on the aeration/non-aeration cycle showed more stable nitrogen removal, showing various microbial community in the reactor. From PCR-DGGE analysis, it is conclusive that Dysgonomonas mossii strain Melo40, Eubacterium sp. oral clone JN088, Uncultured bacterium clone SPESB2_718, and Bacterium enrichment culture clone LE are related with the organics and nitrogen oxidation. Uncultured Acidobacteria bacterium clone AKYG487, Lactobacillus harbinensis strain FQ003, Erythrobacter litoralis strain Gi-3, Phytobacter diazotrophicus strain Ls8, and Mycobacterium sp. enrichment culture clone GE10037biofNNA are distinctly appeared under denitrification condition.

• Journal of Microbiology and Biotechnology
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• v.21 no.5
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• pp.519-524
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• 2011

The correlation between alcoholic fermentation rate, measured as carbon dioxide ($CO_2$) evolution, and the rate of hydrogen sulfide ($H_2S$) formation during wine production was investigated. Both rates and the resulting concentration peaks in fermentor headspace $H_2S$ were directly impacted by yeast assimilable nitrogenous compounds in the grape juice. A series of model fermentations was conducted in temperature-controlled and stirred fermentors using a complex model juice with defined concentrations of ammonium ions and/or amino acids. The fermentation rate was measured indirectly by noting the weight loss of the fermentor; $H_2S$ was quantitatively trapped in realtime using a pre-calibrated $H_2S$ detection tube which was inserted into a fermentor gas relief port. Evolution rates for $CO_2$ and $H_2S$ as well as the relative ratios between them were calculated. These fermentations confirmed that total sulfide formation was strongly yeast strain-dependent, and high concentrations of yeast assimilable nitrogen did not necessarily protect against elevated $H_2S$ formation. High initial concentrations of ammonium ions via addition of diammonium phosphate (DAP) caused a higher evolution of $H_2S$ when compared with a non-supplemented but nondeficient juice. It was observed that the excess availability of a certain yeast assimilable amino acid, arginine, could result in a more sustained $CO_2$ production rate throughout the wine fermentation. The contribution of yeast assimilable amino acids from conventional commercial yeast foods to lowering of the $H_2S$ formation was marginal.