• Title/Summary/Keyword: concentration of nitrite

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The High Rate Denitrification of Nitric Acid Wastewater in a Fluidized Bed Biofilm Reactor (유동층 생물막 반응기를 이용한 고농도 질산성 폐수의 탈질화에 관한 연구)

  • 신승훈;김민수;박동일;안재동;장인용
    • Journal of Environmental Health Sciences
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    • v.23 no.1
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    • pp.95-104
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    • 1997
  • The objectives of this study are to investigate the effect of media on the removal efficiency of nitrate-nitrogen and the biofilm thickness in the fluidized bed biofilm reactor(FBBR) used for the high rate denitrification of nitric acid wastewater. Granular activated carbon(GAC) of 1.274 mm diameter and sand of 0.455 mm diameter were used as the media in the FBBR of 0.05 m diameter and 1.5 m height. As the nitrate-nitrogen concentration of the influent was increased stepwise from 600 to 4800 mg/l, the nitrate- and nitrite-nitrogen concentration of the effluent, biofilm thickness and biofilm dry density were measured to study the effects of media on the denitrification efficiency. The biofilm thickness increased with the substrate loading rate, and the biofilm dry density decreased with the increase of the biofilm thickness. At the influent nitrate-nitrogen concentration of 2400 mg/l, the removal efficiency in the FBBR with GAC was 88%, while that in the FBBR with sand was 99.6%. The biofilm in the FBBR with GAC was so thick, 754.9 $\mu$m, as to increase the mass transfer resistance, compared to that, 143.7 $\mu$m, in the FBBR with sand. The maximum specific denitrification rate in the FBBR with GAC was 15.0 kg-N/m$^3\cdot$ day, while that in the FBBR with sand was 18.0 kg-N/m$^3\cdot$ day. The biomass concentration in the FBBR with sand exhibited the high value 37 kg/m$^3$.

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Analysis of the Contents and Physiological Activities of Calystegia japonica Leaf Extracts (메꽃(Calystegia japonica) 잎 추출물의 함유성분과 생리활성에 관한 연구)

  • Choi, Bok-Dong;Jeon, Ho-Sung;Lee, Yang-Suk;Joo, Eun-Young;Kim, Nam-Woo
    • Korean Journal of Food Science and Technology
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    • v.42 no.2
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    • pp.250-255
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    • 2010
  • This study examined the physiological activities as well as the total polyphenol and flavonoid content of water extract (WE), ethanol extract (EE) and hot water extract of Calystegia japonica leaves under high pressure (HWE). The xanthine oxidase inhibitory rate of EE was the highest with a value of 98.89% at a concentration of 1.0 mg/mL, whereas the rate of WE and HWE was over 90% at a concentration of 0.3 mg/mL. The superoxide dismutase (SOD)-like activity of HWE was the highest at 18.88%. The nitrite scavenging abilities were 64.59-66.46% at conditions of pH 1.2 and 1.0 mg/mL, and 52.78-55.89% at pH 3.0. The electron donating ability of EE was the highest with a value of 84.80% at a concentration of 0.1 mg/mL. All extracts showed the highest degree of electron donating at the concentration of 0.1 mg/ mL, and this effect decreased as the extract concentration increased. The EE had the highest content of total polyphenol compound (173.89 mg/g) and flavonoid compounds (40.68 mg/g).

Nitrogen Removal by Electrochemical Oxidation Using the Tube Type Electrode (튜브형 전극을 이용한 전기화학적 산화에 의한 질소제거에 관한 연구)

  • Cho, Jae-Jun;Jeong, Jong-Sik;Lee, Jae-Bok
    • Journal of Korean Society of Water and Wastewater
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    • v.18 no.5
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    • pp.580-587
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    • 2004
  • The objective of this research is to investigate the electrochemical oxidation process for nitrogen removal in wastewater involving chloride ion and nitrogen compounds. The process experiment of electrochemical oxidation was conducted by using the stainless steel tube type reactor and the $Ti/IrO_2$ as anode. Free chlorine production and current efficiency variation for total nitrogen removal was compared depending on whether electrolyte is added, and the nitrogen type distribution under an operating condition. When chloride was added as electrolyte, it was found that production of free chlorine increased and the concentration of the chloride decreased as retention time passed. The concentration of chloride in influent decreased from 1,660 to 1,198 mg/L at the current density of $6.7A/dm^2$, while concentration of free chlorine increased to 132 mg/L. Current efficiency in removal of ammonium nitrogen was increased when chloride was dosed as electrolyte. It was observed that ammonium nitrogen was oxidized to nitrite and nitrate through electrochemical oxidation and that the concentration of total nitrogen in influent was reduced from 22.58 to 4.00 mg/L at the short retention time of 168 seconds through the electrochemical oxidation of nitrogen.

Evaluation of Anti-oxidant, Anti-microbial and Anti-thrombosis Activities of Fruit, Seed and Pomace of Schizandra chinensis Baillon (오미자 열매, 씨, 착즙 후 박의 항산화, 항균 및 항혈전 활성 평가)

  • Kim, Mi-Sun;Sung, Hwa-Jung;Park, Jong-Yi;Sohn, Ho-Yong
    • Journal of Life Science
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    • v.27 no.2
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    • pp.131-138
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    • 2017
  • In this study, for the efficient use of the byproduct of the omija (Schizandra chinensis Baillon: SC) processing industry, the ethanol extracts of the fruit (F), seed (S), and pomace (P) of SC were prepared, and their useful bioactivities were evaluated. For F-SC, S-SC, and P-SC, the extraction yields were 28.3%, 22.1%, and 7.2%, respectively, and the polyphenol contents were 8.81, 37.22, and 9.20 mg/g, respectively. The total flavonoid content in P-SC (4.31 mg/g) was 3.5-fold higher than that in F-SC (0.76 mg/g). In an antioxidation activity assay, P-SC showed stronger radical scavenging activities against DPPH anion, ABTS cation, and nitrite and stronger reducing power activities than the other extracts. The calculated concentration required for 50% radical scavenging activity, $RC_{50}s$, of P-SC for DPPH anion, ABTS cation, and nitrite was 226.2, 192.5, and $92.5{\mu}g/ml$, respectively. In an antimicrobial activity assay, F-SC, S-SC, and P-SC showed similarly strong growth inhibitions against Bacillus subtilis and P. vulgaris at a concentration of 0.5 mg/disc. F-SC and P-SC showed 15-fold extended time in thrombin, prothrombin, and activated partial thromboplastin time assays at a concentration of 5 mg/ml. The anticoagulation activity of P-SC (2.5 mg/ml) was comparable to that of aspirin (1.5 mg/ml). Furthermore, F-SC and S-SC showed very good platelet aggregation inhibitory activities. F-SC, S-SC, and P-SC did not show significant hemolysis against human red blood cell up to a concentration of 0.5 mg/ml. These results suggest that S-SC and P-SC, both of which are byproducts of the omija processing industry, show strong potential as novel antioxidant, antimicrobial, and antithrombosis agents.

Characteristic study and isolation of Bacillus subtilis SRCM 101269 for application of cow manure (우분 적용을 위한 Bacillus subtilis SRCM 101269의 분리 및 특성 연구)

  • Jeon, SaeBom;Oh, HyeonHwa;Uhm, Tai-Boong;Cho, Jae-Young;Yang, Hee-Jong;Jeong, Do-Youn
    • Korean Journal of Microbiology
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    • v.52 no.1
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    • pp.74-83
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    • 2016
  • Bacillus subtilis SRCM 101269 having safety and amo gene isolated from Korean traditional fermented food and their investigated characterization to apply the cow manure such as cellulase and xylanase activities, 16S rRNA sequencing, and ability of removal of livestock manure odor. Cow manure application results for the removal of livestock manure odor, the ammonia gas was reduced more than two-folder compared to the control group after 6 days, and reduced to less than 10 ppm after 9 days. In the case of cow manure added fowl droppings and other wood-based mixture components, ammonia gas maintained constant after 3 days of fermentation. However, in the case of sample inoculated B. subtilis SRCM 101269, ammonia gas reduced in course of fermentation time, and concentration of hydrogen sulfide also reduced for 65 ppm. Changes of nitrite concentration according to fermentation time no showed different for cow manure, however nitrite concentration in mixed livestock manure increased when compared to control. And then sulfate concentration in cow manure decreased, and no showed different when compared to the initial fermentation. No apparent change of sulfate concentration in mixed livestock manure detected. Through the previously studies, B. subtilis SRCM 101269 has high potential in industrial application manufacturing the cow manure as removal of livestock manure odor.

Effect of Ammonium Concentration on the Emission of $N_2O$ Under Oxygen-Limited Autotrophic Wastewater Nitrification

  • Kim, Dong-Jin;Kim, Yu-Ri
    • Journal of Microbiology and Biotechnology
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    • v.21 no.9
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    • pp.988-994
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    • 2011
  • A significant amount of nitrous oxide ($N_2O$), which is one of the serious greenhouse gases, is emitted from nitrification and denitrification of wastewater. Batch wastewater nitrifications with enriched nitrifiers were carried out under oxygen-limited condition with synthetic (without organic carbon) and real wastewater (with organic carbon) in order to find out the effect of ammonium concentration on $N_2O$ emission. Cumulated $N_2O$-N emission reached 3.0, 5.7, 6.2, and 13.5 mg from 0.4 l of the synthetic wastewater with 50, 100, 200, and 500 mg/l ${NH_4}^+$-N, respectively, and 1.0 mg from the real wastewater with 125 mg/l ${NH_4}^+$-N. The results indicate that $N_2O$ emission increased with ammonium concentration and the load. The ammonium removal rate and nitrite concentration also increased $N_2O$ emission. Comparative analysis of $N_2O$ emission from synthetic and real wastewaters revealed that wastewater nitrification under oxygen-limited condition emitted more $N_2O$ than that of heterotrophic denitrification. Summarizing the results, it can be concluded that denitrification by autotrophic nitrifiers contributes significantly to the $N_2O$ emission from wastewater nitrification.

Environmental Pollutants Drained From Highway Pavement Road

  • Takemura, Shinsaku;Goto, Naoshige;Mitamura, Osamu
    • Korean Journal of Ecology and Environment
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    • v.38 no.spc
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    • pp.58-61
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    • 2005
  • Environmental polluting materials from road surface drainage are a significant nonpoint source influenced to the eutrophication of lake and ecosystems with a transport development in recent years. To elucidate the discharge characteristics, the changing patterns in concentrations of polluting materials such as suspended solid (SS), chemical oxygen demand (COD), nitrogenous and phosphorus nutrients in drainage waters, were investigated during rainfall. Load variation of COD concentration in drainage water samples was closely related to that of SS concentration. This indicates that SS contained a greater part of organic matter. A quite difference between the past pavement and the new well-drainage pavement system was observed in the concentrations of SS and COD in drainage waters. Appreciable concentrations of nitrite and nitrate were determined in drainage waters. The present results indicate that the drainage water from road surfaces is a significant nonpoint source, and that the well-drainage pavement system introduced to skid prevention has an effect on the decreases of pollutants.

The study for the effect of biofilter and ultra-violet disinfector in fish-breeding place using seawater (폐쇄순환 양식장에서의 생물여과기 (biofilter) 및 자외선살균기(ultra-violet disinfector)효과에 대한 연구)

  • 강청근;노기완;류시영;조충희
    • Korean Journal of Veterinary Service
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    • v.22 no.4
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    • pp.357-361
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    • 1999
  • The most harmful nitrogenous compounds in fish-breeding place using are ammonia and nitrate. Excessively high total nitrogen concentration is the signal of unbalance for breeding fishes in seawater and may result overfeeding or overstocking without seawater treatment system. The failure of elimination for the organic ingredients or nitrogen compounds can also cause the consequence of inadequate oxygen concentration in seawater, either. The study shows the effect of biofilter and W disinfector of seawater in the fish- breeding place. In the results, these tools had ammonia, nitrite, nitrate and decreased 71.8%, 27.6% and 1%, respectively, and the total number of microorganisms decreased up to 81.9%.

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Changes in the Endothelin-1-induced Contraction of Aorta in Streptozotocin-induced Diabetic Rats

  • Cheong, Hyun-Joo;Kim, Eun-Jin;Kim, Su-Jin;Lee, Sun-Hee;Rhim, Byung-Yong
    • The Korean Journal of Physiology and Pharmacology
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    • v.4 no.3
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    • pp.185-195
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    • 2000
  • Vascular diseases are significant complications of diabetes mellitus (DM), and the endothelial cells may play a pivotal role in the development of vascular disease in DM. Endothelin-1 (ET-1) released from endothelium is a potent vasoconstrictor peptide and circulating level of ET-1 is increased in a variety of disease states. The purpose of this study was to determine the changes of responsiveness to ET-1 in DM, and we experimented on the changes in the ET-1-induced contraction, levels of nitrite and lipid peroxidation, and ET-1 immunoreactivity in aorta from streptozotocin-induced DM rats. DM was induced by single injection of streptozotocin (55 mg/kg, i.p.). The immunoreactive ET-1 levels in endothelial layer of thoracic aorta were much higher in DM rats than control rats. Nitrite in tissue homogenate was decreased and plasma nitrite was increased in DM rats. Malondialdehyde (MDA) was significantly increased in DM rats and cGMP was not significantly different between control and DM rats. ET-1 produced concentration- dependent contractile responses that are significantly attenuated in DM rats compared to controls. In the presence of selective $ET_A$ receptor antagonist BQ610, the maximum contraction was decreased and the concentration ratios for BQ610 yielded $pA_2$ values of 7.3 (slope, 0.65) in control rats, whereas BQ610 had no antagonistic effect on ET-1-induced contraction in DM rats. However, pretreatment with BQ788, an $ET_B$ receptor antagonist, maximum response was decreased and the dose-response curves for ET-1 were shifted to the right in both groups and $pA_2$ values were 7.9 and 7.7 (slope, 1.05 in control and DM rats), respectively. IRL 1620 and sarafotoxin S6c, $ET_B$ agonists, induced relaxation in control rats but not in DM rats. These results indicate that endothelial cell dysfunction and enhanced immunoreactivity of ET-1 have been found in DM rat and ET-1-induced contraction was attenuated in DM rat. These attenuated responses might be at least in part caused by the alteration of $ET_A$ receptor properties (e.g. desensitization), and partly related with an alteration in intracellular mechanism for contraction to ET-1.

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Comparative analysis of nitrite scavenging activity and anti-inflammation effects in the fruiting bodies of medicinal mushrooms (약용버섯류 자실체의 아질산염 소거능 및 항염증 효능 분석)

  • Cho, Jae-Han;Lee, Gang-Hyo;Han, Jae-Gu;Kim, Hyung-Don;Jhune, Chang-Sung
    • Journal of Mushroom
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    • v.13 no.4
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    • pp.330-333
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    • 2015
  • This study was carried out to compare the anti-inflammation effects of various fruiting body of Ganoderma species and Cordyceps militaris, Phelinus linteus extracts. We concentrated Ganoderma species and other medicinal mushrooms by extracting with ethanol. And We made it $100{\mu}g/ml$ concentration. As a result of nitrite scavenging activity, in the contrast to the positive control; Ascorbic acid was 25%, ASI 7080 of Ganoderma species was disappeared up to around 40%. And in the contrast to Ascorbic acid was 55%, ASI 7002 was 78.5% that was the highest anti-inflammation effect in the result of "No assay test". The Cordyceps militaris showed 75% and Hericium erinaceus showed 59.7% of anti-inflammation effect. As a result of the fungus yield control test of $TNF-{\alpha}$ through ELISA method to ASI 7002 of Ganoderma species that showed the highest anti-inflammation, it was reduced as same as LPS non-treatment. We extracted RNA from ASI 7002 Ganoderma species 10, 50, $100{\mu}g/ml$ concentration and LPS $10{\mu}g/ml$ of Raw 264.7 cell. And we tested the expression of iNOS, COX-2 and TNF-a that are kinds of inflammation gene after synthesizing RNA with cDNA. Finally we could find that iNOS, COX-2 and TNF-a were all controlled expression in the result of above experiment.