• Journal of fish pathology
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• v.36 no.2
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• pp.349-360
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• 2023

Common carp (Cyprinus carpio) (Weight 23.05 ± 6.98 g, Length 12.65 ± 1.38 cm) were exposed to waterborne nitrite at 0, 50, 100, 200, 400 and 800 mg NO₂ ^-/L for 96 hours. The lethal concentration 50 (LC₅₀) of C. carpio exposed to waterborne nitrite was 398.6 mg NO₂ ^-/L. Hemoglobin, hematocrit and RBC count were significantly decreased by waterborne nitrite exposure. The MCV (mean mean corpuscular volume) (µl), MCH (mean corpuscular hemoglobin) (pg) and MCHC (mean corpuscular hemoglobin concentration) (%) were significantly increased. The inorganic component, plasma calcium, was significantly increased, and the organic components such as plasma cholesterol and total protein were significantly increased showing a similar tendency with calcium. In enzymatic components, the AST and ALT were also significantly increased by nitrite exposure. The results of this study indicate that exposure to nitrite can affect the survival and hematological physiology of C. carpio.

• Korean Journal of Biological Psychiatry
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• v.11 no.1
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• pp.33-39
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• 2004

Objective:Nitric oxide(NO) has been known to be associated with tolerance and preference to alcohol. It has also been known to affect various alcohol drinking behavior, alcohol withdrawal symptoms and alcohol- induced brain damage. The purpose of this study was to determine the difference, among alcohol dependence group, alcohol drinking group and abstinence group, in serum concentration of nitrite, a stable metabolite of NO, and it's relationship to clinical and biochemical markers of alcoholism. Methods:Forty subjects diagnosed as alcohol dependence according to DSM-IV diagnostic criteria were evaluated for the clinical characteristics and biochemical markers of alcohol dependence including nitrite with their CIWA-Ar scores checked just after admission. Thirty-nine healthy controls were also evaluated, divided into twenty-three alcohol drinking group and sixteen abstinence group. Clinical characteristics were evaluated by CIWA-Ar, CAGE and AUDIT questionnaires. Aspartate aminotransferase(AST), alanine aminotransferase (ALT), gamma glutamyltransferase(GGT) and mean corpuscular volume(MCV) were used as the biochemical markers of alcohol dependence. Serum nitrite concentrations were measured by Griess reaction. Results:1) The concentrations of nitrite in alcohol dependence patients were not different from those in the control subjects. 2) There were no significant association between the nitrite concentrations and the CIWA-Ar scores in alcohol dependence patients. 3) Nitrites are significantly increased in alcohol dependence group and alcohol drinking group compared with abstinence group. Conclusions:These findings suggest that serum nitrite concentration has no relation with alcohol withdrawal symptoms, but alcohol drinking increases serum nitrite concentration influenced by general condition of the body.

• Journal of Animal Science and Technology
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• v.62 no.5
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• pp.702-712
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• 2020

Synthetic nitrite imparts a reddish-pink color to meat and a distinct flavor to meat products, delays lipid oxidation, and inhibits microbial growth and pathogens. However, excessive intake of nitrite might result in the production of carcinogenic nitrosamine, which might increase the risk of cancer in humans. Therefore, we aimed to find an alternative natural colorant for pork sausages. Pork sausages were mixed with 0.014% sodium nitrite (NaNO₂) alone (CON), without either NaNO₂ or purple-fleshed sweet potato powder (PP; CON1), 0.5% PP alone (PP1), 1% PP (PP2) alone, 0.011% NaNO₂ and 0.5% PP (SP1), and 0.011% NaNO₂ and 1% PP (SP2). The sausages were then cooked and stored for physicochemical analysis on days 0, 5, 10, 15, and 20. The a* and W* values were the greatest and lowest in the SP2 and CON1 treatments, respectively (p < 0.05). The concentrations of residual nitrite in the sausages at 20 days decreased in the order of CON > SP1, SP2 > PP2 > PP1, CON1. The fatty acid content was higher, and flavorous amino acids were more in PP2 (p < 0.05). The fatty acid composition was comparable between the SP2 and CON groups, but the contents of glutamic acid and alanine were greater in the SP2 group. In conclusion, SP2 (0.011% NaNO₂ with 1% PP) could be added as a natural colorant for pork sausage production, and NaNO₂ could be substituted with up to 20% PP without detrimental effects on sausage appearance and/or quality.

• Journal of the Korean Chemical Society
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• v.41 no.5
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• pp.256-265
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• 1997

A rapid and sequential method was studied, which can determine nitrite, nitrate and ammonium ion in soil or water samples with flow injection analysis. Geometric factors including injection volume, length of the reaction coil and flow rate of carrier solution were investigated prior to sample measurement. Nitrite was determined at 540 nm by Griess reaction producing azo dye between N-(1-naphthylethylenediamine dihydrochloride) and sulfanilamide. Nitrate was also measured under the help of reduction mechanism toward nitrite with hydrazine. Ammonium was analyzed at 440 nm with Nessler's reagent. At the optimum condition, the detection limit(S/N=3) has been shown 0.1 ㎍/mL N(NO2-), 0.4 ㎍/mL N(NO3-) and 0.3 ㎍/mL N(NH4+) respectively. The results measured by colorimetry, ion chromatography and FIA were compared showing 80%-125% reasonable match each other. Injection throughput rate could be performed better than 30 times per hour.

• Journal of Korean Society on Water Environment
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• v.30 no.1
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• pp.1-7
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• 2014

The purpose of this study was to investigate the nitrification characteristics of biological aerated filter (BAF) packed with ceramic media, especially focusing on nitrite build-up during nitrification. When increasing the nitrogen load above $1.63kgNH_4{^+}-N/m^3{\cdot}d$, ammonium removal efficiency decreased to less than 60% and the nitrite ratio ($NO_2{^-}-N/NO_x-N$) of higher than 75% was achieved due to the inhibitory free ammonia (FA, $NH_3-N$) concentration and oxygen limitation. FA inhibition, however, is not recommended strategy to promote nitrite build-up since FA concentration in the reactor is coupled with decreased ammonium removal efficiency. Nitrite ratio in the effluent was also affected by aeration rate and influent ammonium concentration. Ammonium oxidation was enhanced at a higher aeration rate regardless of influent ammonium concentration but, the nitrite ratio was dependent on both aeration rate and influent ammonium concentration. While a higher nitrite ratio was obtained when BAFs were fed with $50mgNH_4{^+}-N/L$ of influent, the nitrite ratio significantly decreased for a greater influent concentration of $200-300mgNH_4{^+}-N/L$. Taken together, aeration rate, influent ammonium concentration and FA concentrations kept in the BAF were found to be critical variables for nitrite accumulation in the BAF system.

• Journal of Wetlands Research
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• v.15 no.2
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• pp.265-269
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• 2013

Nitrogen in water is mainly composed of ammonium, nitrite and nitrate, and which can cause eutrophication. A lot of efforts were made to remove them and the accompanying efforts have been made for the development of analytical methods. Rapid and on site detection methods are required for the analysis of pollutants in water system. Thus, we focused on the development of analytical method for nitrite, and the feasibility study on the nitrite analysis by PVC adsorbent columns coated with BCDMA, Biphenyl and methanol. The adsorbents could effectively adsorb mixed reagent in the range of 4 to 20 $mgNO_2-N/L$ for nitrite detection and show linear relationship with color band length. The adsorbance was influenced by pH.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.11a
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• pp.145-146
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• 2020

This study investigated the performance evaluation of polymer cement mortar for repairing concrete structures using calcium nitrite(Ca(NO₂)₂) and CO₂ nano-bubble mixing water to develop section-restoration methods for the repair and reinforcement of cracks. The evaluation items were strength and microstructure analysis at 28 days of age according to the change in the amount of calcium nitrite and the use of CO₂ nano-bubble water. As a result of the experiment, it was confirmed that the performance of polymer cement mortar for repairing concrete structures was improved by the generation of nitrite-based hydration products when calcium nitrite and CO₂ nano-bubble water were used.

• Journal of Marine Life Science
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• v.3 no.2
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• pp.87-95
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• 2018

To investigate effects of starvation on physiological changes, stress response, and survival of cobitid loach (Misgurnus anguillicaudatus) exposed to sodium nitrite (NaNO₂), a 4-week experiment was conducted. Fewer fish survived in the starved group than those in the fed group during the experiment. Starvation resulted in growth retardation, leading to differences in body length and body depth between fed and starved groups. The fed gorup continued to grow and remained in good condition. Blood chemical analysis (plasma cortisol and glucose) showed significant differences in stress response to nitrite exposure between fed and starved groups (p < 0.05). These results suggest that all parameters employed in this study to assess effects of starvation with NaNO₂ stress are useful information for researching nutritional status in cobitid loach.

• Journal of Food Hygiene and Safety
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• v.15 no.2
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• pp.101-107
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• 2000

This experiment was conducted to investigate the effect of NA formation in the human body with salted and dried yellow corvenia(Gulbi, Pseudosciaena manchurica) steamed for 30 minutes and incubated in 10 ml simulated saliva and 40 ml gastric juice at 37。C for 2 hours. And the experiment studied the NA formation after nitrite, thiocyanate and ascorbic acid treatment under simulated gastric conditions. N-nitrosodimethylamine(NDMA) was not detected when nitrite was not added to the digestate mixture. And then increasing the nitrite concentration from 0.5 mM to 8 mM gave a slight increase in the NDMA formation at all level of Gulbi utilized in the experiment. In contrast to the change of the nitrite concentration, the increase of the amount of Gulbi didn't show any marked influence on NDMA formation. At all level of thiocyanate(1∼6.4 mM) tested, concentration of NDMA was still proportional to the nitrite concentration. In the catalytic ability of thiocyanate at another high level of nitrite(100 mM) no catalytic activity was observed up to the level of 8mM thiocyanate. The same amounts of salted fish(10 g) and ascorbic acid levels in each single digestate were used to prevent NDMA formation. No prevention effect was observed at nitrite concentration of 0.5 mM and 1 mM. Most importantly, the decrease of NDMA concentration, by the increase of ascorbic acid absolutely, was remarkably shown when nitrite concentration was high. On the contrary, according to the degree of ascorbic acid, the higher the amount of nitrite the higher the prevention of NDMA formation.

• Environmental Engineering Research
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• v.13 no.3
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• pp.125-130
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• 2008

Free ammonia ($NH_3$-N) inhibition of nitrite-oxidizing bacteria (NOB) has been widely studied for partial nitrification (or nitrite accumulation) and denitrification via nitrite ($NO_2^-$-N) as a low-cost treatment of ammonium containing wastewater. The literature on $NH_3$-N inhibition of NOB, however, shows disagreement about the threshold $NH_3$-N concentration and its degree of inhibition. In order to clarify the confusion, a simple and cheap respirometric method was devised to investigate the effect of free ammonia inhibition of NOB. Sludge samples from an autotrophic nitrifying reactor were exposed to various $NH_3$-N concentrations to measure the maximum specific nitrite oxidation rate ($\hat{K}_{NO}$) using a respirometer. NOB biomass was estimated from the yield values in the literature. Free ammonia inhibition of nitrite oxidizing bacteria was reversible and the specific nitrite oxidation rate ($K_{NO}$) decreased from 0.141 to 0.116, 0.100, 0.097 and 0.081 mg $NO_2^-$-N/mg NOB h, respectively, as the $NH_3$-N concentration increased from 0.0 to 1.0, 4.1, 9.7 and 22.9 mg/L. A nonlinear regression based on the noncompetitive inhibition mode gave an estimate of the Inhibition concentration ($K_I$) of free ammonia to be 21.3 mg $NH_3$-N/L. Previous studies gave $\hat{K}_{NO}$ of Nitrobacter and Nitrospira as 0.120 and 0.032 mg/mg VSS h. The free ammonia concentration which inhibits Nitrobacter was $30{\sim}50\;mg$ $NH_3$-N/L and Nitrospira was inhibited at $0.04{\sim}0.08\;mg$ $NH_3$-N/L. The results support the fact that Nitrobacter is the dominant NOB in the reactor. The variations in the reported values of free ammonia inhibition may be due to the different species of nitrite oxidizers present in the reactors. The respirometric method provides rapid and reliable analysis of the behavior and community of the nitrite oxidizing bacteria.