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Gomes, Tamara Maria, João Carlos Cury Saad, Raimundo Leite Cruz, and Carlos Tadeu dos Santos Dias. "AVALIAÇÃO DA CONCENTRAÇÃO E DISTRIBUIÇÃO DE NITRITO, AMÔNIO E NITRATO PROVENIENTES DA URÉIA APLICADA VIA SISTEMA DE IRRIGAÇÃO POR GOTEJAMENTO." IRRIGA 3, no. 2 (August 12, 1998): 29–35. http://dx.doi.org/10.15809/irriga.1998v3n2p29-35.
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AVALIAÇÃO DA CONCENTRAÇÃO E DISTRIBUIÇÃO DE NITRITO, AMÔNIO E NITRATO PROVENIENTES DA URÉIA APLICADA VIA SISTEMA DE IRRIGAÇÃO POR GOTEJAMENTO[1] Tamara Maria GomesBolsista do CNPq, Av. Independência 1592. CEP: 13416-225. Piracicaba-SP João Carlos Cury SaadRaimundo Leite CruzDepartamento de Engenharia Rural. FCA-UNESP, Cx: 237, CEP: 18.603-970, Botucatu Carlos Tadeu dos Santos DiasDepartamento de Matemática e Estatística ESALQ-USP, Cx: 09, CEP: 13418-900, Piracicaba 1 RESUMO O experimento foi conduzido na área experimental de irrigação do Departamento de Engenharia Rural da Faculdade de Ciências Agronômicas - UNESP/Câmpus de Botucatu, com o objetivo de avaliar a concentração e distribuição de amônio, nitrito e nitrato provenientes do fertilizante uréia em um sistema de irrigação localizada por gotejamento.As amostras de solução do solo foram coletadas nas profundidades de 25, 50 e 75cm em ambos os lados do gotejador (lado esquerdo e direito) com o uso de cápsulas porosas e as concentrações de amônio, nitrito e nitrato existentes foram determinadas em laboratório, utilizando um espectômetro de fluxo contínuo.A adubação via fertirrigação foi realizada com uréia nas doses de 0, 30 e 60 kg de N..ha-1 em três épocas de aplicação, com.a finalidade de estimar a concentração de nitrato, nitrito e amônio após a ultima fertirrigação. Os valores da concentração de amônio e nitrito encontrados nas amostras de solução do solo nos diferentes tratamentos, profundidades e bulbos não atingiram, na maioria das avaliações, teores utilizados como padrão (> 0,2 mg.L-1 e > 0,05mg.L-1, respectivamente). As concentrações de nitrato na solução do solo para as doses de nitrogênio avaliadas nas três profundidades (25, 50 e 75 cm) estudadas não apresentaram diferença significativa, entretanto a concentração de nitrato em relação a posição do gotejador no sentido do fluxo da água foi estatisticamente maior no lado esquerdo, em virtude da declividade do terreno.A baixa concentração de nitrato encontrada na solução do solo por aplicação de uréia, sugere a realização de outros estudos a respeito da concentração e caminhamento do nitrato no solo com o tempo. Para isso recomenda-se um tempo de espera para a coleta de amostras de solução do solo em torno de 30 a 40 dias após aplicação do fertilizante. Outro fator a ser considerado é com relação a instalação dos extratores de cápsulas porosas, que deve ser realizada pouco tempo (1 a 2 dias) antes das amostragens, evitando obstruções das mesmas. UNITERMO: amônio, nitrito, nitrato, fertirigação, gotejamento, cápsula porosa. GOMES, T. M., SAAD, J. C. C., CRUZ, R. L., DIAS, C.T. dos S. Evaluation of the concentration and distribution of nitrite, ammonium e nitrate deriving from the urea applied through trickle irrigation system 2 ABSTRACT This experiment was conducted in the experimental irrigation area of the Department of Rural Engineering of the Faculty of Agronomicae Sciences - UNESP/ Campus of Botucatu, with the objective of evaluating the concentration and distribution of ammonium, nitrite and nitrate deriving from the fertilizer urea in a trickle irrigation localized system.The samples of the soil solution were collected at depths of 25, 50 and 75 cm on both sides of the trickle (left and right side) using porous capsules and the existing concentrations of ammonium, nitrite and nitrate were determined in the laboratory, using a spectrophotometer of continuous flow.The application of fertilizer through fertigation was done with urea in the levels of 0, 30 and 60 kg of N.ha-1 in three times of application, with the aim to estimate the concentration of nitrate, nitrite and ammonium after the last fertigation.The values of the concentrations of ammonium and nitrite found in the samples of the soil solution in the different treatments, depths and bulbs did not reach, in most of the evaluations, contents utilized as standard (>0.2 mg.L-1 and >0.05 mg.L-1, respectively). The concentrations of nitrate in the soil solution for the levels of nitrogen evaluated at the three depths (25, 50 and 75 cm) studied did not show significative difference, although the concentration of nitrate in relation to the position of the trickle in the direction of the water flow was statistically higher on the left side, due to the slope of the soil.The low concentration of nitrate found in the soil solution due to urea application, suggest the accomplishment of other studies involving the concentration and nitrate movement in the soil with the time. Therefore, we recommend a waiting period for the collection of the samples of the soil solution of about 30 to 40 days after the fertilizer application. Another factor to be considered is the installation of extractor of porous capsules, that must be done shortly after (1 to 2 days) the collection of samples, avoiding obstructions in the porous capsules. KEI-WORDS: ammonium, nitrite, nitrate, fertigation, trickle irrigation system, porous capsules.[1] Parte da dissertação do primeiro autor
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Mawaddah, Aida, Roto Roto, and Adhitasari Suratman. "PENGARUH PENAMBAHAN UREA TERHADAP PENINGKATAN PENCEMARAN NITRIT DAN NITRAT DALAM TANAH (Influence of Addition of Urea to Increased Pollution of Nitrite and Nitrate in The Soil)." Jurnal Manusia dan Lingkungan 23, no. 3 (February 27, 2017): 360. http://dx.doi.org/10.22146/jml.22473.
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ABSTRAKNitrat dan nitrit merupakan sumber nitrogen bagi tanaman. Nitrogen sangat diperlukan tanaman untuk pertumbuhan dan perkembangan. Bentuk-bentuk nitrogen di lingkungan mengalami transformasi sebagai bagian dari siklus nitrogen seperti nitrifikasi dan denitrifikasi. Apabila kadar nitrogen dalam tanah rendah, maka urea digunakan sebagai sumber nitrogen. Perubahan urea menjadi nitrit atau nitrat pada beberapa sampel tanah perlu diketahui. Kadar nitrit dan nitrat yang tinggi dapat meningkatkan pencemaran di dalam tanah. Sampel tanah yang digunakan dalam penelitian ini adalah tanah pasir, tanah sawah, tanah pupuk kompos dan tanah pupuk kandang. Analisis nitrit dan nitrat dilakukan dengan menggunakan pereaksi asam p-amino benzoat (PABA) yang dikopling dengan N-naftiletilendiamin (NEDA) dan reduktor spongy cadmium. Sebelum digunakan untuk analisis nitrit dan nitrat, metode divalidasi terlebih dahulu. Hasil validasi metode analisis nitrit dan nitrat dengan pereaksi PABA/NEDA menunjukkan persentase perolehan kembali masing-masing antara 87,15–100,8% untuk nitrit dan 88,16–105,7% untuk nitrat. Setelah ditambah urea sebesar 0,66 g.kg-1 ke dalam tanah, konsentrasi nitrit dan nitrat pada semua sampel tanah mengalami peningkatan. Dari penelitian ini diketahui bahwa peningkatan kadar nitrit dan nitrat setelah ditambahkan urea sangat dipengaruhi oleh kondisi tanah. ABSTRACTNitrate and nitrite were sources of nitrogen for plants. Nitrogen is indispensable for the growth and development of plants. The forms of nitrogen in the environment undergoes a transformation as part of the nitrogen cycle like nitrification and denitrification. If nitrogen level in the soil is low, urea is used as a source of nitrogen. Changes of urea into nitrite or nitrate in some of soil samples need to be known. The levels of nitrite and nitrate are high can increase pollution in the soil. Some of soil samples which is used in this research were sandy soil, paddy soil, compost soil and manure soil. Analysis of nitrite and nitrate were conducted by using a reagent p-amino benzoic acid (PABA) / N-napthylethylenediamine (NEDA) and spongy cadmium as reductor. Before being used for the analysis of nitrite and nitrate, this method was validated first. The results of validation of nitrite and nitrate analysis method by using a reagents PABA / NEDA showed the percent recovery were respectively 87.15-100.8% for nitrite and 88.16-105.7% for nitrate. After the addition of 0.66 g.kg-1 urea into the soil, nitrite and nitrate concentration in all soil sample has increased. Based on this research was known that the increased levels of nitrite and nitrate after the addition of urea was influenced by soil condition.
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Ayala Armijos, Jose Humberto, Carlos Garcia Gonzalez, Raquel Sanchez Prado, Yiceth Jiron Velez, and Washington Espinoza Ramon. "Efecto de la adición de ácido ascórbico en la degradación de nitratos y nitritos en mortadela / Effect of addition of ascorbic acid in the degradation of nitrate and nitrite in mortadella." Ciencia Unemi 9, no. 20 (December 20, 2016): 85. http://dx.doi.org/10.29076/issn.2528-7737vol9iss20.2016pp85-92p.
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El objetivo de la presente investigación fue evaluar el efecto de la adición de ácido ascórbico (Vitamina C) para reducir la concentración de nitritos y nitratos adicionada a la mortadela como conservante. Se realizaron tres formulaciones de mortadela a las cuales se añadió tres concentraciones diferentes de ácido ascórbico (F1: 0,25 g/kg, F2: 0,50 g/kg y F3: 0,75 g/kg) y un testigo, mediante espectrofotometría UV-Visibles se cuantificó la concentración inicial y la final para comprobar la reducción de nitratos y nitritos y la formación de color y el ácido ascórbico residual se lo cuantificó mediante voltametría. El análisis de varianza aplicado al experimento nos indicó que si existió diferencia significativa (p˂0,05) eentre los tres tratamientos estudiados, se alcanzó reducciones de nitratos del 30,78 % en la F1, 50 % en la F2 y 76 % en la F3, en este caso la reducción de nitratos y valores de nitrito formado de 0,41 mg/kg en la F1, 0,24 mg/Kg en la F2 y 0,04 mg/Kg en la F3, en la formación de nitritos. La F3 presentó el mayor % de reducción de nitratos y la menor cantidad de formación de nitritos. En conclusión la adición de ácido ascórbico a la mortadela reduce la concentración residual de nitratos al cabo de tres días, donde ya no se presentó reducción significativa de este conservante. ABSTRACTThe aim of this research was to evaluate the effect of the addition of ascorbic acid to reduce the concentration of nitrites and nitrates in mortadella. Three formulations of mortadella were tested to which three different concentrations of ascorbic acid (0.25 g / kg, F2: 0.50 g / kg and 0.75 g F3 / kg F1) were added. Through UV-visible spectrophotometry it was quantified the initial and final concentration of nitrates and nitrites and color formation, and the residual ascorbic acid was quantified by voltammetry. The analysis of variance indicated that there was significant difference (p˂0,05) among the three treatments. Nitrate reduction of 30.78% in F1, F2 50% at 76% and the values of F3 and formed nitrite 0.41 mg / kg in F1 0.24 mg / kg was achieved in F2 and 0.04 mg / kg in F3, in the formation of nitrite. F3 showed the highest percentage reduction of nitrates and the least amount of formation of nitrite. In conclusion, the addition of ascorbic acid to mortadella reduces the residual nitrate concentration after three days, where no longer significant reduction of this preservative was presented.
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Chen, J., Q. Xiao, F. H. Wu, Z. M. Pei, J. Wang, Y. G. Wu, and H. L. Zheng. "Nitric oxide emission from barley seedlings and detached leaves and roots treated with nitrate and nitrite." Plant, Soil and Environment 56, No. 5 (May 7, 2010): 201–8. http://dx.doi.org/10.17221/231/2009-pse.
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Nitric oxide (NO) emission from detached barley leaves, roots and whole plants treated with various nitrate or nitrite concentrations under light/dark and aerobic/anaerobic conditions was quantified by using a chemiluminescence detector. NO emission from detached tissues and whole plants treated with moderate nitrate concentration (60mM) was relatively higher under anaerobic condition, and was positively correlated with nitrite concentration. Darkness and anaerobic condition remarkably induced NO emission from detached barley leaves. On the contrary, NO emission from detached roots and whole plants was relatively higher in light. As for whole plants treated with 60mM nitrate and 12mM nitrite, the pattern of NO emission in normal environment was broken by light-dark and aerobic-anaerobic transition. Light and anaerobic condition induced NO emission significantly in the whole plant. The whole barley plant emitted significantly higher amount of NO than detached leaves or roots.
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Drysdale, G. D., H. C. Kasan, and F. Bux. "Assessment of denitrification by the ordinary heterotrophic organisms in an NDBEPR activated sludge sytem." Water Science and Technology 43, no. 1 (January 1, 2001): 147–54. http://dx.doi.org/10.2166/wst.2001.0036.
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The purpose of this study was to isolate and characterise the ordinary heterotrophic organisms (OHOs) present in a NDBEPR system in order to gain a better understanding of the organisms involved in denitrification as well as a more holistic and accurate evaluation of the OHO fraction attributable to denitrification in such a system. Heterotrophic bacteria were isolated from the pre- and secondary anoxic zones of the Darvill NDBEPR process and characterised according to their ability to reduce nitrates and/or nitrites under anoxic conditions. Results showed that the OHO fraction is more complex than currently accepted and, with respect to denitrification, can be more accurately subdivided into five functional groups, four of which interactively contribute to denitrification occurring in the system and one group that are non-denitrifying. These groups were defined as true denitrifiers (bacteria capable of both nitrate and nitrite reduction), incomplete denitrifiers (bacteria that reduced nitrates to nitrites with no further reduction of the nitrites produced), incomplete-nitrite reducers (bacteria capable of both nitrate and nitrite reduction, however, exhibiting severe inhibition of nitrite reduction by nitrates), exclusive nitrite reducers (bacteria only capable of reducing nitrites) and non-denitrifiers (bacteria not capable of nitrate or nitrite reduction).
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Paulionytė, Skaistė, and Aušra Mažeikienė. "BIOLOGICAL NITROGEN REMOVAL FROM WASTEWATER IN COLD PERIOD / BIOLOGINIS AZOTO JUNGINIŲ ŠALINIMAS IŠ NUOTEKŲ ŠALTUOJU LAIKOTARPIU." Mokslas – Lietuvos ateitis 8, no. 4 (October 24, 2016): 468–74. http://dx.doi.org/10.3846/mla.2016.957.
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Today the number of individual wastewater treatment plants in the country is increasing. Popular are biological treatment, activated sludge-based operating units. There are almost no data on how the wastewater disposed of nitrogen compounds, especially in the cold (winter) period. The article analyzes the small domestic wastewater treatment plant AT-6 available in the main clean-up indicators (pH, T, SS, BOD7, nitrate nitrogen, nitrite nitrogen, ammonia nitrogen concentrations). The investigation period as the AT-6 type device treated wastewater in line with the general requirements of the natural environment, effluents (depending on the temperature, odor, pH, and SS, BOD7 concentrations). Nitrate nitrogen and nitrite nitrogen concentrations in the effluent of the device did not exceed the requirements into the natural environment effluents. Ammonium nitrogen concentration in the treated wastewater the entire study period exceeded requirements (5 m. / l) of the discharge into the natural environment. It should be more research during the cold months to confirm this. Šiandien individualių buitinių nuotekų valymo įrenginių skaičius šalyje vis didėja. Populiarūs biologinio valymo veikliojo dumblo pagrindu veikiantys įrenginiai. Beveik nėra duomenų, kaip iš nuotekų šalinami azoto junginiai, ypač šaltuoju (žiemos) laikotarpiu. Straipsnyje analizuojami mažu buitinių nuotekų biologinio valymo įrenginiu AT-6 pasiekiami pagrindiniai išvalymo rodikliai (pH, temperatūra, SM, BDS7, nitratų azoto, nitritų azoto, amonio azoto koncentracijos). Tyrimų laikotarpiu AT-6 tipo įrenginiu išvalytos nuotekos atitiko bendruosius reikalavimus į gamtinę aplinką išleidžiamoms nuotekoms (pagal temperatūrą, kvapą, pH, SM ir BDS7 koncentracijas). Nitratų azoto ir nitritų azoto koncentracijos įrenginio ištakyje neviršijo reikalavimų į gamtinę aplinką išleidžiamoms nuotekoms. Amonio azoto koncentracija išvalytose nuotekose visą tyrimo laikotarpį viršijo reikalavimus (5 mg/l) išleidžiant nuotekas į gamtinę aplinką. Reikėtų atlikti daugiau tyrimų šaltuoju metų laikotarpiu rezultatams patvirtinti.
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Saputra, Alfian Dony, Haeruddin Haeruddin, and Niniek Widyorini. "EFEKTIVITAS KOMBINASI MIKROORGANISME DAN TUMBUHAN AIR Lemna minor SEBAGAI BIOREMEDIATOR DALAM MEREDUKSI SENYAWA AMONIAK, NITRIT, DAN NITRAT PADA LIMBAH PENCUCIAN IKAN." Management of Aquatic Resources Journal (MAQUARES) 5, no. 3 (December 20, 2016): 80–90. http://dx.doi.org/10.14710/marj.v5i3.14393.
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ABSTRAK Limbah pencucian ikan bersumber dari kegiatan pencucian bagian luar dan dalam tubuh ikan. Limbah pencucian ikan memiliki kandungan senyawa amoniak, nitrit, dan nitrat yang tinggi sehingga kemungkinan mempunyai efek negatif bagi lingkungan. Sebagian besar industri pengolahan ikan belum melakukan pengolahan limbah cairnya dengan baik. Bioremediasi merupakan metode biologi dengan memanfaatkan mikroorganisme dan tumbuhan air Lemna minor dalam pengolahan air limbah. Penelitian ini bertujuan untuk mengetahui efektivitas dan pengaruhdari kombinasi mikroorganisme dan Lemna minor dalam mereduksi senyawa amoniak, nitrit, dan nitrat pada limbah pencucian ikan. Metode penelitian yang digunakan adalah eksperimen skala laboratorium dimana wadah percobaan berisi limbah pencucian ikan dengan volume 1 Liter. Desain penelitian yang digunakan yaitu percobaan faktorial 3 x 3 dengan 2 faktor, sehingga terdapat 9 kombinasi perlakuan M1L10, M1L50, M1L100, M5L10, M5L50, M5L100, M10L10, M10L50, dan M10L100, dimana “M” faktor konsentrasi mikroorganisme (1 mL/L, 5 mL/L, 10 mL/L), sedangkan “L” faktor bobot biomassaLemna minor (0,0255 gr/cm2, 0,1273 gr/cm2 , 0,2546 gr/cm2). Variabel utama penelitian adalah amoniak, nitrit, dan nitrat yang didukung oleh temperatur, pH, dan oksigen terlarut. Analisis data dengan menggunakan analisis efektivitas, uji two way Anova, dan uji Beda Nyata Jujur. Hasil penelitian menunjukkan bahwa nilai efektivitas berkisar antara 40,85% - 74,03% (amoniak), 42,21% - 74,10% (nitrit), dan 3,19% - 34,65% (nitrat). Pengaruh interaksi kombinasi mikroorganisme dan Lemna minor yaitu terdapat pengaruh yang nyata dan efektif dalam mereduksi senyawa amoniak, nitrit, dan nitrat pada limbah pencucian ikan. Kata Kunci: Amoniak; Bioremediasi; Lemna minor; Limbah Pencucian Ikan; Mikroorganisme; Nitrat; Nitrit ABSTRACT Fish washery waste derived from washing inner and outer part of fish body.Fish washery waste containshigh ammonia, nitrite, and nitrate which may have negative effect for the environment.Most of the fish processing industry are not doing the processing of waste water properly yet. Bioremediation is a biological method by using microorganisms and aquatic plant Lemna minor in wastewater treatment. The aims of study is to determine the effectiveness anda effect of the use of microorganism and Lemna minor combination in effort to reduce ammonia, nitrite, and nitrate compound in fish washery waste. The method used is laboratory-scale experiments where the experimental containers containing fish washery waste with a volume of 1 Liter. 3 x 3 factorial with 2 factor method design were used, so there are nine treatment combinations of M1L10, M1L50, M1L100, M5L10, M5L50, M5L100, M10L10, M10L50, and M10L100, where "M" forconcentrationof microorganisms factor (1 mL/L, 5mL/L, 10 mL/L), while the "L" for biomass weight of Lemna minorfactor (0,0255 gr/cm2, 0,1273 gr/cm2 , 0,2546 gr/cm2). The main variable of this study are ammonia, nitrite, and nitrate supported by temperature, pH, and Dissolved Oxygen. The data was analyzed using effectiveness analysis, two way Anova, and Least Signifficant Difference methode. The results show that the concentration of ammonia, nitrite, and nitrate decreased after 96 hours for all treatmentscombination. The effectiveness value, ranged between 40.85% - 74.03% (ammonia), 42.21% - 74.10% (nitrite), and 3.19% - 34.65% (nitrate). There is a signifficant influence and effective in combination of microorganisms and Lemna minor to reduce ammonia, nitrite, and nitrate compound in fish washery waste. Keywords: Ammonia; Bioremediation; Lemna minor; Fish Washery Waste; Microorganism; Nitrate;Nitrite
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Ginting, Nahitma, Jansen Silalahi, Tuty Roida Pardede, Sudarmi Sudarmi, and Nerdy Nerdy. "EFFECT OF HARVESTING TIME AT MORNING, AFTERNOON, AND EVENING ON NITRATE AND NITRITE LEVEL IN SPINACH (AMARANTHUS TRICOLOR L.) AND MUSTARD (BRASSICA RAPA L.)." Asian Journal of Pharmaceutical and Clinical Research 11, no. 13 (April 26, 2018): 110. http://dx.doi.org/10.22159/ajpcr.2018.v11s1.26581.
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Objective: The objective of this study is to determine the effect of harvesting time at morning, afternoon, and evening on nitrate and nitrite level in spinach and mustard.Methods: Nitrite identification was done using sulfanilic acid reagent and N-(1-naphthyl) ethylenediamine dihydrochloride. Identification of nitrate was done using reagent ferrous sulfate. Determination of nitrites level was performed visible spectrophotometry using N-(1-naphthyl) ethylenediamine dihydrochloride at maximum wavelength of 540 nm. Nitrate determination is taken with the same method but started with reduction process from nitrate into nitrite using Zn powder in acid condition and then measured as nitrite.Results: Research result shows that there is a change of nitrate and nitrite level from the spinach harvested at morning, afternoon, and evening.Conclusion: Spinach and mustard are better harvested in the morning because it contains nitrite less than in spinach picked afternoon and evening. Level of nitrite increases from morning to afternoon and decreases from afternoon to evening. However, the level of nitrate decreases from morning to afternoon and increases from afternoon to evening.
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Fogarasi, Erzsébet, Ibolya Fülöp, Emanuela Marcu, and Mircea Dumitru Croitoru. "Presence of Nitrate and Nitrite in Well Water in Mureș County." Acta Medica Marisiensis 62, no. 1 (March 1, 2016): 78–81. http://dx.doi.org/10.1515/amma-2015-0063.
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AbstractObjective: One of the most important sources of nitrite and nitrate anions, besides vegetables and meat products, is the drinking water. Presence of nitrite and nitrate in the water in higher concentrations than those set by EFSA (0.5 mg/l nitrite, 50 mg/l nitrate), may have toxicological significance. A quantitative determination of these ions in samples collected from several pleases from Mureș County was made. Methods: Ninety-seven well water samples were tested from 12 different places from Mureș County. We used a simple HPLC-UV ion pair method for the determination of nitrite and nitrate concentrations. Sensitivity of the method enables the quantification for concentrations far below the MCL value. Results: The highest amounts of nitrate and nitrite were measured in Sangeorgiu de Mureș and Cristești. Concentrations of nitrite and nitrate were exceeded in 4.12% and respectively 44.32% of the samples. Conclusions: The high amounts of nitrites and nitrates existing in well water go beyond the expected extent. This pollution can become a health risk since this water is used in human nutrition especially in child nourishment.
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Silalahi, Jansen, Shena Keshia Aritonang, and Muchlisyam. "The Effect of Boiling Time and the Type of Utensil Used on the Nitrite and Nitrate Contents in Carrots (Daucus carota L.)." Indonesian Journal of Pharmaceutical and Clinical Research 1, no. 1 (April 16, 2018): 18–27. http://dx.doi.org/10.32734/idjpcr.v1i1.208.
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Abstract. The purpose of this study was to investigate the effect of boiling time using utensils made of different metal component on thenitrate and nitrite contentsin carrots. The carrots were obtained from Jaranguda Village, Karo Regency, North Sumatra. The utensil types used for boiling were made of stainless steel, what so called periuk and aluminum and boiling time were 5 minutes, 10 minutes and 15 minutes.The determination of nitrite was done by visible spectrophotometer using sulfanilic acid and N-(1-naphthyl) ethylenediamine dihydrochloride reagentsand absorbance was measured at a wavelength of 540 nm. The determinationof nitrate wascarried out by reducing the nitrate into nitrite using Zinc powder and diluted HCl then measured as nitrite. The nitritelevel was then convertedinto nitrate. The result showed that the utensil types and boiling time affected the levels of nitrate and nitrite in carrots. The nitrate and nitrite levels in fresh carrots was 32.14 mg/kg and 24.78 mg/kg respectively. After boiling for 5 minutes, the nitrate and nitrite levels decreased significantly. Further boiling of boiled carrots, the nitrite levelincreased in the aluminum utensil from 11.00 mg/kg to 20.15 mg/kg (83 %); in periuk from 9.18 mg/kg to 16.95 mg/kg (78%) andin stainless steelfrom 8.21 mg/kg to 11.75 mg/kg (43%). While the nitrate level decreased in aluminumutensil from 27.14 mg/kg to 21.08 mg/kg (22%); stainless steel from 16.40 mg/kg to 13.25 mg/kg (19%) and periuk from 20.30 mg/kg to 16.51 mg/kg (18%). The results of this study indicated that the nitrite level increased, while nitrate level decreased with boiling time.The effect of utensil type used on boiling increased nitrite but decreased nitrate level in carrotsand these effects were found that the mostinfluential treatmentwas using utensil made of aluminum.
Keyword: Carrot, Boiling Time, Nitrate, Nitrit, Utensil Type
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LIN, KUEN-SONG, NI-BIN CHANG, and TIEN-DENG CHUANG. "DECONTAMINATION OF NITRATES AND NITRITES IN WASTEWATER BY ZERO-VALENT IRON NANOPARTICLES." Nano 03, no. 04 (August 2008): 291–95. http://dx.doi.org/10.1142/s1793292008001283.
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The chemical reduction of nitrate or nitrite species by zero-valent iron nanoparticle (ZVIN) in aqueous solution and related reaction kinetics or mechanisms using fine structure characterization were investigated. Experimentally, ZVIN of this study was prepared by borohydride reduction method at room temperature. The morphology of as-synthesized ZVIN shows that the nearly ball and ultrafine particles ranged of 20–50 nm were observed with FE-SEM analysis. The kinetic model of nitrites or nitrates reductive reaction by ZVIN is proposed as a pseudo-first-order kinetic equation. The nitrite and nitrate removal efficiencies using ZVIN were found 65–83% and 51–68%, respectively, based on three different initial concentrations. By using XRD patterns, the quantitative relationship between nitrite and Fe(III) or Fe(II) becomes similar to the one between nitrate and Fe(III) in the ZVIN study. The possible reason is linked with a faster nitrite reduction by ZVIN. In fact, the occurrence of the relative faster nitrite reductive reaction suggested that the passivation of the ZVIN have a significant contribution to iron corrosion. The XANES spectra show that the nitrites or nitrates reduce to N 2 while oxidizing the ZVIN to Fe 2 O 3 or Fe 3 O 4 electrochemically. It is also very clear that decontamination of nitrate or nitrite species in groundwater via the in-situ remediation with a ZVIN permeable reactive barrier would be environmentally attractive.
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KATSOULOS (Π. Δ. ΚΑΤΣΟΥΛΟΣ), P. D., N. PANOUSIS (Ν. ΠΑΝΟΥΣΗΣ), and H. KARATZIAS (Χ. ΚΑΡΑΤΖΙΑΣ). "Nitrate poisoning in ruminants." Journal of the Hellenic Veterinary Medical Society 55, no. 3 (December 6, 2017): 226. http://dx.doi.org/10.12681/jhvms.15098.
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This paper describes the nitrate - nitrite poisoning of ruminants. This disease is caused by the ingestion of large amount of nitrate salts, which are reduced in the rumen to nitrite ions. Nitrites, after their absorption, cause the formation of methemoglobin and, in turn, respiratory and circulatory distress. The aim of the treatment is to reduce the percentage of methemoglobin in blood and to stop the continuing production of nitrite ions in the rumen. For the prevention of the disease, avoidance of feedstuff rich in nitrates and improvement of the water quality, are suggested.
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Sutardi, Aris, Slamet Suprayogi, and Tjahyo Nugroho Adji. "Kajian Kualitas Airtanah Bebas antara Sungai Kuning dan Sungai Tepus di Kecamatan Ngemplak, Yogyakata, Indonesia." Majalah Geografi Indonesia 31, no. 1 (April 21, 2017): 31. http://dx.doi.org/10.22146/mgi.24230.
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Pertumbuhan penduduk di Kabupaten Sleman telah menempatkan banyak tekanan pada sumber daya air. Perkembangan ini berkembang pesat ke daerah pedesaan termasuk Ngaglik, Ngemplak dan Kalasan Kecamatan. Oleh karena itu, studi tentang kualitas air di daerah ini penting. Daerah antara Sungai Kuning dan Sungai Tepus merupakan daerah yang ideal untuk melakukan penelitian ini saerah ini meliputi 3 kecamatan yaitu: Ngaglik, Ngemplak dan Kalasan. Dalam penelitian ini, parameter untuk menilai kualitas air terbatas pada 4 parameter: Nitrat, Nitrit, Amoniak dan Fosfat. Penelitian ini dilakukan pada tahun 2015, pengambilan sampel purposive dipilih untuk mengumpulkan besar sampel air tanah. Penggunaan lahan dan kegiatan lain yang dianggap dapat menyebabkan polusi air seperti pertanian, catel, dan limbah domestik. Sampel dianalisis di laboratorium untuk menentukan konsentrasi Nitrat, Nitrit, amoniak dan fosfat. Secara total, 23 sampel dikumpulkan. Selama kerja lapangan, tabel air diukur untuk menghasilkan peta flownet. Peta flownet ini akan digunakan untuk menganalisis potensi pencemaran air tanah. Hasil penelitian ini menunjukkan bahwa Nitrat, Nitrit, amoniak, dan fosfat yang bervariasi. Kontaminasi Nitrat dan Nitrit dalam air tanah masih di bawah standar sebesar 10 mg / L untuk Nitrat dan 0,06 mg / L untuk Nitrit sementara amoniak dan fosfat berada di atas standar sebesar 0,02 mg / L untuk amoniak dan 0,2 mg / L untuk fosfat. Tingginya jumlah amoniak ini disebabkan oleh kegiatan peternakan ayam sementara fosfat disebabkan oleh penggunaan pemupukan fosfat di daerah pertanian padi. Distribusi kualitas air tanah di daerah itu bervariasi berdasarkan penggunaan lahan, kegiatan orang dan aliran air tanah. Air tanah potensial pencemaran dilakukan berdasarkan aliran air tanah. Hasilnya menunjukkan bahwa daerah atas (utara) memiliki konsentrasi yang lebih rendah dari Nitrat, Nitrit, amoniak dan fosfat. Daerah pertengahan, di mana sebagian besar peternakan ayam dan pertanian berada, telah menjadi sumber pencemaran air. Population growth in Sleman regency have put a lot of pressure on water resources. This development is growing rapidly into the rural area including Ngaglik, Ngemplak and Kalasan Sub-district. Therefore, study about water quality in these area is important. The area between Kuning River and Tepus River is an ideal area to conduct this research since its cover 3 sub-districts: Ngaglik, Ngemplak and Kalasan. In this research, the parameter to assess water quality is limited to 4 parameters: Nitrate, Nitrite, Ammoniac and Phosphate. The study was conducted in 2015. Purposive sampling was selected to collect the groundwater sampels. Landuse and other people activities that can contribute to water pollution such as farming, catel, and domestic waste were considered. The samples were analysed in laboratory to define the concentration of Nitrate, Nitrite, ammoniac and phosphate. In total, 23 samples were collected. During fieldwork, the water table were measured to generate the flownet map. This flownet map will be used to analyse the groundwater pollution potential. The result of this research shows that the Nitrate, Nitrite, ammoniac, and phosphate were varies. The contamination of Nitrate and Nitrite in the groundwater is still below standard by 10 mg/L for Nitrate and 0,06 mg/L for Nitrite while ammoniac and phosphate were above standard by 0,02 mg/L for ammoniac and 0,2 mg/L for phosphate. These high number of ammoniac were caused by the chicken farming activities while phosphate were caused by the use of phosphate fertilization in the rice farming area. The distribution of groundwater quality in the area were varies based on the landuse, people activities and groundwater flow. The groundwater potential pollution were conducted based on the groundwater flow. The result show that the upper area (north) has lower concentration of Nitrate, Nitrite, ammoniac and phosphate. The mid area, where most of the chicken farm and rice farm are located, has become the sources of the water pollution.
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Chatterjee, Amrita, Dipratn G. Khandare, Praveen Saini, Anjan Chattopadhyay, Mahesh S. Majik, and Mainak Banerjee. "Amine functionalized tetraphenylethylene: a novel aggregation-induced emission based fluorescent chemodosimeter for nitrite and nitrate ions." RSC Advances 5, no. 40 (2015): 31479–84. http://dx.doi.org/10.1039/c4ra14765k.
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A novel AIE-based fluorescent probe for the detection of trace amounts of nitrite and nitrate ions in water has been developed, which spontaneously detects nitrites (or nitrates) by a fluorescence “turn-off” method.
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Putri, Wike Ayu Eka, Anna Ida Sunaryo Purwiyanto, Fauziyah, Fitri Agustriani, and Yulianto Suteja. "KONDISI NITRAT, NITRIT, AMONIA, FOSFAT DAN BOD DI MUARA SUNGAI BANYUASIN, SUMATERA SELATAN." Jurnal Ilmu dan Teknologi Kelautan Tropis 11, no. 1 (April 1, 2019): 65–74. http://dx.doi.org/10.29244/jitkt.v11i1.18861.
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ABSTRAKPesisir Banyuasin merupakan salah satu sentra perikanan tangkap di Provinsi Sumatera Selatan. Kawasan ini menyimpan potensi sumber daya perikanan yang harus dijaga kelestariannya. Banyak nelayan yang menggantungkan hidupnya di kawasan ini, hanya saja ragam pemanfaatan di sepanjang aliran Sungai Banyuasin seperti pemukiman, industri, pertanian dan transportasi telah mempengaruhi kualitas perairan. Penelitian ini bertujuan untuk mengkaji bagaimana kondisi nitrat, nitrit, amonia, fosfat dan BOD di Pesisir Banyuasin. Pengambilan sampel dilakukan pada bulan September 2017 meliputi 22 stasiun penelitian, analisa sampel dilakukan di Laboratorium Balai Riset dan Standardisasi Industri (Baristand) Palembang merujuk pada SNI. Hasil penelitian menunjukkan konsentrasi nitrat selama penelitian berkisar antara 0,025-3,21 mg/L, nitrit 0,002-0,093 mg/L, amonia 0,002-0,031 mg/L, fosfat 0,011-0,231 mg/L dan BOD 2,14-8,73 mg/L. Konsentrasi nitrat dan fosfat telah melebihi baku mutu yang ditetapkan, adapun untuk parameter nitrit, amonia dan BOD masih dibawah baku mutu. ABSTRACTCoastal of Banyuasin is one of the centers of capture fisheries in South Sumatra Province. This area had the potential of fisheries resources that must be preserved. Many fishermen are depend their lives on this area, but some activity along Banyuasin River such as settlement, industry, agriculture and transportation has affected the quality of water. This study aims to examine the conditions of nitrate, nitrite, ammonia, phosphate and BOD in the Coastal of Banyuasin. Sampling was conducted in September 2017 covering 22 research stations, sample analysis conducted at Palembang Institute for Industrial Research and Standaritation Laboratory refers to SNI. The results showed that the concentration of nitrate during the study ranged from 0.025-3.21 mg.L-1, nitrite 0.002-0.093 mg.L-1, ammonia 0.002-0.031 mg.L-1, phosphate 0.011-0.231 mg.L-1and BOD 2.14-8.73 mg.L-1. The concentration of nitrate and phosphate in Banyuasin River estuary were exceeded quality standards while nitrite, ammonia and BOD were still below specified quality standards.
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Casella, Sergio, Anita Toffanin, Stefania Ciompi, Nora Rossi, and W. J. Payne. "Metabolism of nitrogen oxides and hydroxylamine in cells of true denitrifiers and Rhizobium "hedysari" HCNT1." Canadian Journal of Microbiology 40, no. 1 (January 1, 1994): 1–5. http://dx.doi.org/10.1139/m94-001.
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Cells of several copper-protein denitrifiers that produce nitrite reductase reduced nitrate to gaseous products but were completely or strongly inhibited by the copper chelator diethyldithiocarbamate (DDC), which did not comparably inhibit cells of cytochrome ed1 nitrite reductase producers. Both types of true denitrifiers released NO while reducing nitrite anaerobically in the presence of the uncoupler 3-chlorophenylhydrazonepropanedinitrile (CCCP), as seen previously only in Paracoccus denitrificons. In contrast, the pseudodenitrifier Rhizobium "hedysari" HCNT1, which grows as neither adenitrifier nor a fermenter, failed to reduce nitrate or nitrite or to nitrify ammonia when grown aerobically but reduced nitrite to N2O after growth at low oxygen tension even without any nitrogen oxide in the culture medium. Such oxygen-limited cells also formed N2O when incubated anaerobically with NO and hydroxylamine, and with nitrite and hydroxylamine as well, but not when anaerobic nitrite reduction (i.e., apparent production of NO) was inhibited by DDC. Rhizobium "hedysari" HCNT1 cells released no NO while reducing nitrite even in the presence of CCCP. The use of CCCP may permit differentiation of respiratory from nitrite-detoxifying denitrifying bacteria. Under aeration, but not anoxia, NO and hydroxylamine reacted to form N2O even in the absence of cells, providing a possible indicator of NO production assayable by gas chromatography.Key words: nitrite, nitric oxide, diethyldithiocarbamate (DDC), hydroxylamine, 3-chlorophenylhydrazonepropanedinitrile (CCCP).
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Gutyj, B., K. Leskiv, A. Shcherbatyy, V. Pritsak, V. Fedorovych, O. Fedorovych, and V. Rusyn. "The influence of Metisevit on biochemical and morphological indicators of blood of piglets under nitrate loading." Regulatory Mechanisms in Biosystems 8, no. 3 (July 29, 2017): 427–32. http://dx.doi.org/10.15421/021767.
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The article presents the results of research on the influence of the developed complex preparation Metisevit on the dynamics of morphological and biochemical blood indicators of piglets under nitrate loading. The research established that sodium nitrate intoxication causes disbalance of the physiological level of hematological indicators of the tested animals’ organisms. This was indicated by the manifestations of subclinical chronic nitrate-nitrite toxicosis: the increase in the level of nitrates, nitrites and methemoglobin in the blood. After prolonged feeding of the piglets with sodium nitrate at a dose of 0.3 g nitrate ion/kg, the concentration of nitrates and nitrites in the blood serum reached its maximum on the 60th day of the experiment. Also, the number of leukocytes and erythrocytes in the blood increased, and the activity of aspartate- and alanineaminotransferase in the blood serum increased. We rank the extent of liver intoxication with nitrates according to intensity of aminotransferase in the blood serum of the tested piglets. The normalization of morphological and biochemical indicators of blood of piglets under nitrate-nitrite intoxication requires usage of a preparation which contains vitamins, zeolites and antioxidants. If the fodder contains high doses of nitrates, 1.0 mg/kg dose of Metisevit is added to the fodder for preventing subclinical nitrate-nitrite toxicosis. Metisevit contains the following agents: phenozan acid, methionine, zeolite, selenium, vitamins E and C. The research conducted proved the feasibility of using Metisevit for preventing chronic nitrate-nitrite toxicosis in piglets. This preparation caused a decrease in the concentration of nitrates, nitrites and in the level of methemoglobin in the blood of piglets. Usage of Metisevit on piglets showed normalization of the number of erythrocytes and hemoglobin in the blood on the 10th day, and normalization of ASAT and ALAT on 30th and 90th days. The mechanism of Metisevit activity is connected with the direct contribution of its elements to the inhibition of the processes of absorbing metabolites which cause a toxic effect on the cell membranes of an animal’s organism. The absorbing activity of zeolite leads to decrease in concentration of agents which can be substrates for processes of peroxidation of lipids in the alimentary canal, and also to elimination of toxic pro-oxidant metabolites from the blood. This process occurs through osmosis and diffusion of these elements in the capillaries of microvilli of the small intestine and through their further fixation on sorbent granules.
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MOTTELET, S., A. FILALI, S. GUERIN-RECHDAOUI, V. ROCHER, S. AZIMI, and A. PAUSS. "Mesure en ligne des concentrations d’ions nitrites et nitrates pour l’optimisation de la dénitrification et la réduction de la production de protoxyde d’azote." Techniques Sciences Méthodes, no. 6 (June 22, 2020): 23–32. http://dx.doi.org/10.36904/tsm/202006023.
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Cette étude vise à évaluer la capacité d’une sonde à rayons ultraviolets (UV) à estimer simultanément les teneurs en nitrate et nitrite en sortie d’une unité de biofiltration en postdénitrification. L’estimation de ces deux espèces est compliquée du fait de la très grande similitude de leur spectre UV et de la présence d’autres molécules absorbantes dans l’UV. Celle-ci est pourtant indispensable au développement d’algorithmes de contrôle, seuls à même de garantir un résiduel en nitrite et nitrate conforme aux exigences de la directive cadre sur l’eau. La sonde WTW Nitra Vis 705 IQ NI a été calibrée puis validée en laboratoire sur un effluent réel dans une gamme de 0 à 3,5 mgN/L en nitrite. Elle a ensuite été installée en sortie d’une unité de biofiltration de la station de Seine Centre afin d’évaluer sa capacité à prédire les dynamiques de concentrations en nitrites et nitrates. Le suivi a montré que, moyennant une calibration multipoint pour le nitrite et multilinéaire pour le nitrate, il est possible de mesurer simultanément et dynamiquement le nitrite dans la gamme 0-5 mgN/L avec une précision de 0,2 mgN/L et le nitrate dans la gamme 0-10 mgN/L avec une précision de 0,3 à 0,4 mgN/L. Les mesures en ligne de protoxyde d’azote dissous, effectuées sur site au moyen de sondes ampérométriques, montrent que la dynamique est similaire à celle du nitrite en fonction du ratio DBO/N-NO3– appliqué, et que l’on obtient une meilleure corrélation du protoxyde d’azote avec le nitrite (R2 = 0,72) comparativement à la somme nitrite + nitrate (R2 = 0,52).
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GOVARI (Μ. ΓΚΟΒΑΡΗ), M., and A. PEXARA (Α. ΠΕΞΑΡΑ). "Nitrates and Nitrites in meat products." Journal of the Hellenic Veterinary Medical Society 66, no. 3 (January 31, 2018): 127. http://dx.doi.org/10.12681/jhvms.15856.
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Nitrates and nitrites have been traditionally used as curing agents in the production of cured meat products. Beneficial effects of the addition of nitrates and nitrites to meat products are the improvement of quality characteristics as well as the microbiological safety. The nitrates and nitrites are mainly responsible for the development of the distinct flavor, the stability of the red color, as well as the protection against lipid oxidation in cured meat products. The nitrites show important bacteriostatic and bacteriocidal activity against several spoilage bacteria as well as foodborne pathogens found in meat products. The nitrites prevent the growth and toxin production by Clostridium botulinum. According to Commission Regulation (EU) No. 1129/2011, nitrates (sodium nitrate, E251; potassium nitrate, E252) and nitrites (potassium nitrite, E249; sodium nitrite, E250) are listed as permitted food additives. Nitrates are relatively non-toxic, but nitrites, and nitrites metabolic compounds such as nitric oxide and N-nitroso compounds, have raised concern over potential adverse health effects. Recently, the International Agency for Research on Cancer (IARC) concluded that ingested nitrates or nitrites are probable carcinogen to humans under conditions favoring the endogenous nitrosation. Legal limits for the addition of nitrates and nitrites have been set by several countries and EU [Commission Regulation (EU) No. 601/2014]. Several data from recent reviews conducted in several countries on the levels of nitrates and nitrites in cured meat products were summarized. In recent reviews, the residual levels of nitrites in cured meat samples have been constantly reduced and are in accordance with the legal limits set by most countries.
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Izidoro Apezteguia Martinez, José Henrique. "Características de um Rio Cárstico na Bacia do São Francisco (Characteristics of a Cárstico River in the São Francisco Basin)." Revista Brasileira de Geografia Física 10, no. 5 (August 24, 2017): 1576. http://dx.doi.org/10.26848/rbgf.v10.5.p1576-1594.
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Este trabalho teve como objeto de estudo o Córrego do Barreado localizado na mesorregião do oeste do estado de Minas Gerais, que tem sua bacia contida na região da bacia do Alto São Francisco sobre relevo cárstico. A Bacia do São Francisco abastece 14,2 milhões de habitantes em 6 estados, sendo assim importante o conhecimento de suas características limnológicas. Para se avaliar as águas do Córrego do Barreado foi efetuado um monitoramento hidrológico mensal de um ano, entre outubro de 2014 e setembro de 2015, os parâmetros avaliados foram: precipitação, vazão, temperatura, condutividade, oxigênio dissolvido, pH, turbidez, nitrito, nitrato, ortofosfato e amônia. O acumulado de chuva anual entre outubro de 2014 e setembro de 2015 foi 1464,8 mm, as médias de cada parâmetro para todo o Córrego do Barreado foram respectivamente: oxigênio dissolvido (OD) – 2,83 mg/l, pH – 7,25, turbidez – 53,6, nitrito – 0,03 mg/l de NO2, nitrato – 0,14 mg/l de NO3, ortofosfato – 0,05 mg/l de P, amônia – 0,16 mg/l NH3. Conclui se que a combinação da impropriedade da qualidade das águas, ocupação do solo e alta sensibilidade dos aquíferos cársticos amplificam efeitos poluidores no Córrego do Barreado, que alteram suas características com efeito percebido principalmente nos valores de oxigênio dissolvido.Palavras-chave: água, relevo cárstico, monitoramento hidrológico, usos da água.A B S T R A C TThis study object was the Córrego do Barreado located in the mesoregion of the western state of Minas Gerais, which has its basin inserted in the region of the Upper São Francisco basin on karst relief. The São Francisco River Basin supplies 14.2 million inhabitants in 6 states, so it is important to know its limnological characteristics. The following parameters were evaluated: rainfall, flow, temperature, conductivity, dissolved oxygen, pH, turbidity, nitrite, precipitation, precipitation, nitrate, orthophosphate and ammonia. The annual rainfall accumulated between October 2014 and September 2015 was 1464.8 mm, the mean of each parameter for the entire Barreado Stream were: OD - 2.83 mg / l, pH - 7.25, turbidity - 53.6, nitrite – 0.03 mg/l de NO2, nitrate - 0.14 mg/l de NO3, orthophosphate - 0.05 mg/l de P, ammonia - 0.16 0,16 mg/l NH3. It is concluded that the combination of water quality improperness, soil occupation and high sensitivity of the karstic aquifers amplify polluting effects in the Barreado Stream, which alter their characteristics with a perceived effect mainly on the values of dissolved oxygen.Keywords: water, carstic relief, hidrologic monitoring, warer uses.
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Fernandes, Monique Carolina Nunes, Flávia Barbosa Silva Botelho, Kamila Rezende Dázio de Souza, Gabrielle Carvalho Pereira, Camila Soares Cardoso da Silva, and Douglas Goulart Castro. "ATIVIDADE DA ENZIMA NITRATO REDUTASE EM ARROZ DE TERRAS ALTAS SOB CONDIÇÕES DE ESTRESSE HÍDRICOS." Nativa 8, no. 4 (July 31, 2020): 484–89. http://dx.doi.org/10.31413/nativa.v8i4.9707.
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A assimilação de nitrogênio é um processo vital que controla o crescimento e desenvolvimento da planta, garantindo bons níveis de produtividade de grãos. A enzima nitrato redutase (NR) catalisa o primeiro passo enzimático da assimilação de nitrogênio pelas plantas superiores por meio da redução do nitrato (NO3-) a nitrito (NO2-). Assim, objetivou-se estudar a atividade da enzima redutase do nitrato em genótipos de arroz de terras altas e correlacioná-la com os demais caracteres agronômicos. O experimento foi conduzido em dois ambientes distintos, com e sem irrigação suplementar. As análises de atividade enzimática foram realizadas em laboratório. Foram avaliados 20 genótipos de um experimento de VCU na safra 2014/2015. O delineamento experimental foi em blocos casualizados com três repetições. Foi obtida a quantidade de nitrito liberado pelos tecidos vegetais na solução de incubação (µmoles NO2- gmf -1 h-1) em sete coletas realizadas aos 7, 14, 21, 28, 45, 75 e 100 dias após emergência (DAE), sempre no período da manhã, em todas as parcelas. Diante dos resultados, observou-se que a atividade da enzima NR, na cultura do arroz, é dependente do genótipo, do período de desenvolvimento vegetal e das condições ambientais, sendo de maior expressão no início do ciclo da cultura e em ambientes sem a ocorrência de estresse hídrico. A atividade da enzima RN não deve ser utilizada isoladamente para seleção indireta no caráter produtividade na cultura do arroz de terras altas, é necessário avaliar outras características que complementem à seleção.Palavras-chave: Oryza sativa; nitrogênio; melhoramento de plantas; expressão enzimática. ACTIVITY OF THE NITRATE REDUCTASE ENZYME IN UPLAND RICE UNDER WATER STRESS CONDITIONS ABSTRACT:Nitrogen uptake is a vital process that controls plant growth and development, ensuring great grain yield levels. The enzyme nitrate reductase (NR) catalyzes the first enzymatic step of nitrogen uptake by higher plants by reducing nitrate (NO3-) to nitrite (NO2-). Thus, the objective was to study the activity of nitrate reductase enzyme in upland rice genotypes and to correlate it with other agronomic traits. The experiment was conducted in two distinct environments, with and without supplemental irrigation. The enzymatic activity assays were performed in the laboratory. Twenty genotypes of a VCU experiment in the 2014/2015 crop were evaluated. The experimental design was in randomized blocks with three replications. The amount of nitrite released by the plant tissues in the incubation solution (µmoles NO2-gmf -1 h-1) was obtained in seven collections performed at 7, 14, 21, 28, 45, 75 and 100 days after emergence (DAE). always in the mornings, in all installments. Given the results, it was observed that the activity of NR enzyme in rice culture is dependent on genotype, plant development period and environmental conditions, being more expressive at the beginning of the crop cycle and in environments without occurrence of water stress. The activity of the RN enzyme should not be used alone for indirect selection in the productivity character in the upland rice crop, it is necessary to evaluate other characteristics that complement the selection.Keywords: Oryza sativa; nitrogen; plant breeding; enzymatic expression.
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Stief, Peter, and Dietrich Neumann. "Nitrite formation in sediment cores from nitrate-enriched running waters." Fundamental and Applied Limnology 142, no. 2 (May 26, 1998): 153–69. http://dx.doi.org/10.1127/archiv-hydrobiol/142/1998/153.
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TYRPENOU, A. E., E. H. GOUTA (E.H. ΓΟΥΤΑ), A. D. TSIGOURI (Α.Δ. ΤΣΙΓΟΥΡΗ), and Ch N. VLASIOTIS (Χ.Ν. ΒΛΑΣΙΩΤΗΣ). "Nitrate and nitrite residues in Greek pastirma." Journal of the Hellenic Veterinary Medical Society 51, no. 4 (January 31, 2018): 302. http://dx.doi.org/10.12681/jhvms.15691.
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In this research, for the investigation of the nitrate and nitrite content of Greek pastirma samples coming from several Greek meat processing factories were examined. Nitrate and nitrite determination was carried out following the standard methods of the International Standard Organization ISO No. 2918/751 and 3091/75.2 According to these Standard Operating Procedures-SOPs, reducing capacity of cadmium column should always has to be >90%. Because this critical point usually causes problems [never was >70%], we succeeded and validated this point by amending 3 points of the Standard Operating Procedure [SOP]. These amendments referred to the replacement of the buffer pH 9,6 of the cadmium column with the buffer pH 12,0 according to the method of Margeson et al., 1980.3 The result was that the reducing capacity of the cadmium column increased from 70% to 90-105%. Thirty pastirma samples have been tasted and the concentrations determined ranged from 0,85 to 189,65mg/kg for nitrites and from 2,66 to 639,67mg /kg for nitrates expressed as sodium nitrite. Nitrites, in 56,66% of the samples and nitrates in 83,33% of the samples were ranging in the limits foreseen by the Greek Legislation.
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Habibah, Nur, I. G. A. Sri Dhyanaputri, I. Wayan Karta, and Ni Nyoman Astika Dewi. "Analisis Kuantitatif Kadar Nitrit dalam Produk Daging Olahan di Wilayah Denpasar Dengan Metode Griess Secara Spektrofotometri." International Journal of Natural Science and Engineering 2, no. 1 (April 18, 2018): 1. http://dx.doi.org/10.23887/ijnse.v2i1.13907.
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Nitrite is one of important food additive that used as a preservative and curing agent for the meat product. Since the adverse effect of nitrites to the human health has been reported, the government regulated maximum allowable nitrite content in meat product is 125 mg/kg. Hence, continuous monitoring of the existence of nitrite, especially in the meat products are important to conducted. Quantitative analysis of nitrite in the meat product, especially sausage has been described. The spectrophotometric measurement of the nitrite contents was conducted by using Griess method. The absorbance of both standard solution and sample carried after 30 minutes at the maximum wavelength 520 nm. A linier calibration curve was obtained in the range of 0.1-0.5 ppm, with the R2 value is 0.997. Subsequently, the method was applied to determine the nitrit contents in sausage samples. The spectrophotometric determination showed there were 6 samples have nitrite contents more than maximum allowable nitrite content in the meat product.
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Jones, Trevor. "Nitrate/nitrite." In Practice 15, no. 3 (May 1993): 146–47. http://dx.doi.org/10.1136/inpract.15.3.146.
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von Schulthess, R., D. Wild, and W. Gujer. "Nitric and nitrous oxides from denitrifying activated sludge at low oxygen concentration." Water Science and Technology 30, no. 6 (September 1, 1994): 123–32. http://dx.doi.org/10.2166/wst.1994.0259.
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To determine the net-production of the denitrification intermediates nitric oxide (NO) and nitrous oxide (N2O), two batch experiments with different nitrite concentrations have been performed (A: 3.5 g NO2−-Nm−3, B: 12 g NO2−-Nm−3). In these experiments the concentration of oxygen in the reactor has been varied from 4 g O2m−3 to 0 g O2m−3. As NO and N2O might be produced by nitrifiers as well, the sludge used was unable to nitrify due to a low sludge age. High nitrite as well as aerobic conditions favor the production of N2O but not the production of NO. Furthermore, NO was accumulated at very low concentration and the highest emission was under completely anoxic conditions. A mathematical model has been formulated describing the reduction of nitrate, nitrite, and nitrous oxide. Noncompetitive inhibition of these processes by oxygen and nitrite has been included in the kinetics. The estimated parameters indicate that nitrite serves mainly as a denitrification intermediate rather than as an inhibitor. The net-production of N2O at low oxygen concentrations can be explained by different oxygen inhibition of the three reduction steps. The fast reduction of N2O is most inhibited by oxygen. As a consequence, the reduction of N2O is a slower process under low oxygen pressure than the reduction of nitrate and nitrite.
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Bachvarova, Darina, Renay Rafi, and Aleksandar Doichinov. "The Impact of Environmental Factors on the Amount of Nitrates and Nitrites in Different Types of Soils and Ways of Their Utilization." Acta Scientifica Naturalis 4, no. 1 (March 1, 2017): 100–105. http://dx.doi.org/10.1515/asn-2017-0016.
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Abstract Despite the last decade considerable advances in the study of nitrate and nitrite pollution of soil, there are still some gaps in research related to neglecting or ignoring the role of soil in the food chain and its effects on upper trophic units. The article presents the results of a study on the impact of air and soil humidity and temperature, as well as soil type and utilization on the amount of nitrates and nitrites in the soil solution at the end of vegetation period. It was proved that statistically significant impact on the amounts of residual nitrate and nitrite ions was caused by the temperature and moisture of soil, its type, and the specific properties of the crops grown.
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Nuriani, Layli, Hairul Basri, and Khairullah Khairullah. "Analisis Kelas Mutu Air Berdasarkan Baku Mutu di Sub DAS Kalarengkih Kabupaten Aceh Tengah." Jurnal Ilmiah Mahasiswa Pertanian 3, no. 3 (August 1, 2018): 260–69. http://dx.doi.org/10.17969/jimfp.v3i3.8286.
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Abstrak. Penelitian ini bertujuan untuk mengetahui kelas mutu air untuk kebutuhan penduduk berdasarkan baku mutu di sekitar Sub DAS Kalarengkih Kabupaten Aceh Tengah.. Lokasi di Sub DAS Kalarengkih Kecamatan Bintang Kabupaten Aceh Tengah. Penelitian menggunakan metode deskriptif kuantitatif yang dilaksanakan melalui survei lapang dan analisis laboratorium. Untuk pengambilan sampel air dilakukan dengan cara purposive sampling yaitu pengambilan sampel dengan cara penarikan sampel yang dilakukan memilih subjek berdasarkan kriteria spesifik yang dianggap tepat dan sesuai terhadap fenomena yang diteliti yaitu terdiri dari 5 titik sampel. analisis kelas mutu air sungai mempergunakan baku mutu sebagai pembanding untuk kelayakan kualitas parameter sungai yaitu Peraturan Pemerintah No 82 Tahun 2001 yaitu mengkaji data baku mutu air hanya untuk parameter fisika (TSS, TDS, Temperatur, Kekeruhan) dan kimia (Nitrat, Nitrit, pH, BOD, COD, Sulfat) selanjutnya dapat ditentukan klasifikasi airnya. Hasil Kelas Mutu Air Sub DAS kalarengkih berdasarkan baku mutu pada titik 1 tergolong Kelas 1 yang berada pada hulu Sub DAS Kalarengkih. Pada titik 2, 3, 4 dan 5 tergolong Kelas 4 dengan faktor pembatas Nitrit yang melebihi batas ambang baku mutu, disamping itu pada titik 4 juga terdapat nilai Nitrat yang tinggi, Nitrit terdapat pada outlet yang berada pada areal persawahan sedangkan Nitrat outletnya berada pada areal pemukiman, hal ini diduga Nitrit berasal dari hasil pemupukan dan Nitrat diduga hasil dari buangan limbah pemukiman.Analysis Class of Water Quality Based on Quality Standard in Kalarengkih Wateshed Regency of Aceh TengahAbstract. This study aims to determine the quality class of water for the needs of the population based on quality standards around the Kalarengkih Sub-Basin Central Aceh Regency .. Location in Kalarengkih Sub DAS Sub-District Bintang Regency Central Aceh. The research used quantitative descriptive method implemented through field survey and laboratory analysis. For the sampling of water is done by purposive sampling that is sampling by way of sampling conducted by choosing subject based on specific criterion which is deemed appropriate and appropriate to phenomenon studied that consist of 5 point sample. analysis of river water quality class using quality standard as a comparison for the feasibility of river parameter quality that is Government Regulation No. 82 Year 2001 that is studying data of water quality standard only for physics parameter (TSS, TDS, Temperature, Turbidity) and chemistry (Nitrate, Nitrite, pH, BOD, COD, Sulfate) can then be determined water classification. Results Quality Class Water Sub DAS kalarengkih based on the quality standard at point 1 Class Class 1 located in the upstream Kalarengkih Sub-watershed. At point 2, 3, 4 and 5 belong to Class 4 with limiting factor of Nitrite which exceed the quality standard threshold, beside that at point 4 there is also high Nitrate value, Nitrite is in outlet located in rice field area while Nitrate outlet is in area settlement, it is suspected Nitrite comes from the result of fertilization and Nitrate is suspected to result from disposal of waste settlement.
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López-Espí, Pablo, Sancho Salcedo-Sanz, Ángel M. Pérez-Bellido, Irene de Bustamante, and Francisco López-Ferreras. "Nitrates/nitrites concentration estimation in wastewater samples using transmittance curve models optimized by evolutionary computation techniques." Journal of Hydroinformatics 12, no. 4 (January 6, 2010): 446–57. http://dx.doi.org/10.2166/hydro.2010.016.
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This paper presents an application of evolutionary computation algorithms in the estimation of the concentration of nitrates/nitrites in water. Specifically, we start from the measured transmittance curves of a water sample and a model of the curve consisting of a mixture of polynomial, Fermi and Gaussian functions. An evolutionary programming algorithm is then used to obtain the optimal parameters of the model which minimize the distance between the measured and the modeled transmittance curves. This process allows us to separate the modeled transmittance curve into several components, one of them associated with the nitrate/nitrite concentration. We can extract the nitrate/nitrite concentration of the water sample using this component of the transmittance model. We test our proposal on several laboratory samples and on three real samples measured in different locations around Madrid, Spain.
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Ferysiuk, Karolina, and Karolina M. Wójciak. "Reduction of Nitrite in Meat Products through the Application of Various Plant-Based Ingredients." Antioxidants 9, no. 8 (August 5, 2020): 711. http://dx.doi.org/10.3390/antiox9080711.
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Nitrite is the most commonly applied curing agent in the meat industry, and is known to affect human health. Nitrites impart a better flavor, taste and aroma; preserve the red-pinkish color of the meat; and prevent the risk of bacterial contamination of the cured meat, especially from Clostridium botulinum. Unfortunately, recent research has demonstrated some negative effects of this technique. Certain N-nitroso compounds have been shown to stimulate gastric cancer; therefore, most of the research groups are studying the effects of nitrates and nitrites. In this review, we discuss the various food sources of nitrites and nitrates and their current legal requirements for use in meat products. We also discuss the possible changes that might come up in the regulations, the concerns associated with nitrates and nitrites in meat products, and the use of plant-based nitrite and nitrate substitutes. All these topics will be considered with respect to ensuring a high level of microbiological protection, oxidative stability and acceptable sensory quality (color, taste and smell) in meat products.
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Grandett, Liliana, Sony Reza, Juan De Dios Jaraba Navas, and Yuri Pardo. "Efecto de la actividad microbiana sobre la nitrifiación en suelos cultivados con Brachiaria humidicola (Rendle) Schweicerdt en Cereté, Córdoba." Temas Agrarios 20, no. 2 (November 12, 2015): 9–18. http://dx.doi.org/10.21897/rta.v20i2.754.
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Los fertilizantes nitrogenados en la agricultura han incrementado las emisiones de óxidos de Nitrógeno a la atmósfera. En este trabajo se evaluó la producción de NO2- (nitrito) y NO3- (nitrato) de microorganismos del suelo durante la época seca y de lluvias, en el Centro Investigación Turipaná de Corpoica, Cereté, Colombia. Se utilizó un diseño de parcelas divididas con bloques completamente al azar, con tres accesiones de Brachiaria humidicola (CIAT 16888, CIAT 26159 y CIAT 679), tres dosis de nitrógeno (0, 150 y 300 kg ha-1), dos épocas de aplicación y tres repeticiones por tratamiento. Parcelas sin cobertura vegetal fueron usadas como control. Se determinó el número más probable (NMP) de colonias de bacterias productoras de nitrito y nitrato en la época seca y lluviosa, se evaluó la velocidad de producción de nitritos, nitratos y nitratos totales (nitritos + nitratos) en la época lluviosa, al inicio (Mayo) y al fial (Septiembre) de la fertilización nitrogenada. El mayor NMP se encontró a 300 kg ha-1 de N y la más alta producción de nitritos y nitratos se encontró en las parcelas sin cobertura. Las accesiones CIAT 16888 y CIAT 279 presentaron las menores producciones de nitratos y nitratos en todos los tratamientos en ambos muestreos. Las accesiones de B. humidicola utilizadas en este estudio redujeron la producción de nitritos y nitratos en condiciones de campo, por lo que constituyen una pastura importante en las estrategias de reducción de emisiones de óxidos nitrosos a la atmósfera.
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Anaya Pajuelo, Rosalía, Maritza Vernaza Morales, and Victor Zevallos Narro. "Investigación de la acción de los nitratos y nitritos contenidos en algunos vegetales como causantes de metahemoglobinemia." Ciencia e Investigación 2, no. 1 (June 14, 1999): 1–10. http://dx.doi.org/10.15381/ci.v2i1.4401.
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El efecto tóxico más preocupante de la intoxicación de nitratos y nitritos es la metahemoglobinemia.La metahemoglobinemia reduce la capacidad de transporte de oxígeno por la sangre y además cambia la curva de disociación de oxihemoglobina hacia la izquierda lo cual interfiere con la descarga de oxígeno. Puede ocurrir también hipotensión y colapso.La preocupación principal puede frente a la exposición de nitratos es su reducción biológica a nitrito reactivo y tóxico.El mayor uso del nitrato es como fertilizante. También se usa en la fabricación de nitritos, óxido nitroso, explosivos, pirotecnias, fósforos, aditivo alimentario.El nitrito se usa como preservante en las comidas y para el curado de las carnes, en la sintesis de diazoicos, en la industria textil y fotográfica.Se determinó por Cromatografia Gas - Liquido las concentraciones de nitratos y nitritos en diferentes especies vegetales que supuestamente causan metahemoglobinemia, encontrándose una concentración promedio preocupante de nitratos en: beterraga 2,139 ppm; nabo 2,038 ppm; espinaca 1,195 ppin; alfalfa 66 ppm; zanahoria 404 ppm.Los sintomas de la metahemoglobinemia fueron evaluados experimentalmente en perros administrándoles diferentes dosis de unasolucián de nitrito de sodio. Posteriormente se cuantificó la metahemoglobinemia por el método espectrofotométrico observándose que la dosis de 50 mgl kg de peso in vivo causó 78% de metahemoglobinemia.
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De Luca, Chiara, Agnese Gugliandolo, Carlo Calabrò, Monica Currò, Riccardo Ientile, Desanka Raskovic, Ludmila Korkina, and Daniela Caccamo. "Role of Polymorphisms of Inducible Nitric Oxide Synthase and Endothelial Nitric Oxide Synthase in Idiopathic Environmental Intolerances." Mediators of Inflammation 2015 (2015): 1–10. http://dx.doi.org/10.1155/2015/245308.
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Oxidative stress and inflammation play a pathogenetic role in idiopathic environmental intolerances (IEI), namely, multiple chemical sensitivity (MCS), fibromyalgia (FM), and chronic fatigue syndrome (CFS). Given the reported association of nitric oxide synthase (NOS) gene polymorphisms with inflammatory disorders, we aimed to investigate the distribution of NOS2A −2.5 kb (CCTTT)nas well as Ser608Leu and NOS3 −786T>C variants and their correlation with nitrite/nitrate levels, in a study cohort including 170 MCS, 108 suspected MCS (SMCS), 89 FM/CFS, and 196 healthy subjects. Patients and controls had similar distributions of NOS2A Ser608Leu and NOS3 −786T>C polymorphisms. Interestingly, the NOS3 −786TT genotype was associated with increased nitrite/nitrate levels only in IEI patients. We also found that the NOS2A −2.5 kb (CCTTT)11allele represents a genetic determinant for FM/CFS, and the (CCTTT)16allele discriminates MCS from SMCS patients. Instead, the (CCTTT)8allele reduces by three-, six-, and tenfold, respectively, the risk for MCS, SMCS, and FM/CFS. Moreover, a short number of (CCTTT) repeats is associated with higher concentrations of nitrites/nitrates. Here, we first demonstrate that NOS3 −786T>C variant affects nitrite/nitrate levels in IEI patients and that screening for NOS2A −2.5 kb (CCTTT)npolymorphism may be useful for differential diagnosis of various IEI.
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Moshage, H., B. Kok, J. R. Huizenga, and P. L. Jansen. "Nitrite and nitrate determinations in plasma: a critical evaluation." Clinical Chemistry 41, no. 6 (June 1, 1995): 892–96. http://dx.doi.org/10.1093/clinchem/41.6.892.
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Abstract Plasma nitrite and nitrate determinations are increasingly being used in clinical chemistry as markers for the activity of nitric oxide synthase and the production of nitric oxide radicals. However, a systematic evaluation of the determination of nitrite and nitrate in plasma has not been performed. In this study the recovery and stability of nitrite and nitrate in whole blood and in plasma, the relation between nitrite and nitrate concentrations in plasma, and possible sources of artifacts were investigated. The main conclusions are: (a) Recovery of nitrite and nitrate from plasma is near-quantitative (87%) and reproducible; (b) nitrite and nitrate are stable in (frozen) plasma for at least 1 year; (c) nitrite in whole blood is very rapidly (> 95% in 1 h) oxidized to nitrate, and therefore plasma nitrite determination alone is meaningless; (d) the ranges of nitrite and nitrate concentrations in plasma samples of 26 healthy persons are 1.3-13 mumol/L (mean 4.2 mumol/L) and 4.0-45.3 mumol/L (mean 19.7 mumol/L), respectively; (e) plasma nitrite and nitrate concentrations were not correlated (nitrite as % of total nitrite + nitrate varied from 3.9% to 88% in plasma samples); and (f) plasma samples should be deproteinized, and background controls for each sample should be included in the assay, to avoid measuring artifactually high nitrite and nitrate concentrations in plasma.
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Gates, Andrew J., Victor M. Luque-Almagro, Alan D. Goddard, Stuart J. Ferguson, M. Dolores Roldán, and David J. Richardson. "A composite biochemical system for bacterial nitrate and nitrite assimilation as exemplified by Paracoccus denitrificans." Biochemical Journal 435, no. 3 (April 13, 2011): 743–53. http://dx.doi.org/10.1042/bj20101920.
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The denitrifying bacterium Paracoccus denitrificans can grow aerobically or anaerobically using nitrate or nitrite as the sole nitrogen source. The biochemical pathway responsible is expressed from a gene cluster comprising a nitrate/nitrite transporter (NasA), nitrite transporter (NasH), nitrite reductase (NasB), ferredoxin (NasG) and nitrate reductase (NasC). NasB and NasG are essential for growth with nitrate or nitrite as the nitrogen source. NADH serves as the electron donor for nitrate and nitrite reduction, but only NasB has a NADH-oxidizing domain. Nitrate and nitrite reductase activities show the same Km for NADH and can be separated by anion-exchange chromatography, but only fractions containing NasB retain the ability to oxidize NADH. This implies that NasG mediates electron flux from the NADH-oxidizing site in NasB to the sites of nitrate and nitrite reduction in NasC and NasB respectively. Delivery of extracellular nitrate to NasBGC is mediated by NasA, but both NasA and NasH contribute to nitrite uptake. The roles of NasA and NasC can be substituted during anaerobic growth by the biochemically distinct membrane-bound respiratory nitrate reductase (Nar), demonstrating functional overlap. nasG is highly conserved in nitrate/nitrite assimilation gene clusters, which is consistent with a key role for the NasG ferredoxin, as part of a phylogenetically widespread composite nitrate and nitrite reductase system.
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Tatarczak-Michalewska, Małgorzata, Jolanta Flieger, Justyna Kawka, Wojciech Płaziński, Wojciech Flieger, Eliza Blicharska, and Dariusz Majerek. "HPLC-DAD Determination of Nitrite and Nitrate in Human Saliva Utilizing a Phosphatidylcholine Column." Molecules 24, no. 9 (May 6, 2019): 1754. http://dx.doi.org/10.3390/molecules24091754.
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The aim of this research was to optimize the separation and quantitative determination of nitrites and nitrates in human saliva. HPLC with UV absorption (HPLC/DAD) using a phosphatidylcholine column (IAM.PC.DD2 Regis HPLC) was applied in this assay. Nitrates were detected directly by their absorbance at 210 nm, whereas nitrites were detected after oxidation to nitrates by potassium permanganate at acidic conditions. The kinetics of the permanganate–nitrite reaction was measured chromatographically. The calibration graph for nitrates was linear in the range of 0.5–35 µg mL−1 with a correlation coefficient of 0.9999. The limit of detection was 4.56 ng mL−1. The calibration graph for nitrites (after oxidation to nitrates) was linear in the range of 0.5–15 µg mL−1 with a correlation coefficient of 0.9972. The limit of detection was 4.21 ng mL−1. The nitrate concentrations in the saliva samples were found in the range of 8.98–18.52 μg mL−1, whereas nitrite was in the range of 3.50–5.34 μg mL−1.
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Mukhamejanova, Akmaral, Zerekbay Alikulov, Nelya Shapekova, Karlygash Aubakirova, and Abilkhas Mukhtarov. "The effect of antioxidants on xanthine oxidase activity in fresh ovine milk." Potravinarstvo Slovak Journal of Food Sciences 15 (July 12, 2021): 599–607. http://dx.doi.org/10.5219/1662.
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In the present, the consequences of nitrate pollution of the environment are very pronounced. In humans and animals, microorganisms can reduce nitrates to nitrites, which cause cancer. Purified and homogeneous xanthine oxidase (XO) of cow's milk can restore these compounds, which makes the article extremely relevant. The purpose of the article is to determine the effect of antioxidants on the activity of xanthine oxidase in fresh ovine milk. Various natural and artificial antioxidants were examined for the detection of xanthine oxidase (XO) activity in ovine milk. Among the natural antioxidants, L-cysteine was more effective in the stabilization of XO in heated milk. XO of sheep milk activated by heat treatment in the presence of cysteine and molybdenum became able to convert nitrate and nitrite to nitric oxide (NO). Therefore, L-cysteine was used for double purposes: as the protector of enzyme active center against the oxidation during heat treatment of milk and as a reagent for S-nitrosothiol formation. Hypoxanthine, as a natural substrate of XO, is an effective electron donor for nitrate reductase (NR) and nitrite reductase (NiR) activities. Heat treatment of the milk in the presence of exogenous lecithin increased the activity of NR and NiR of XO and CysNO formation. Thus, during the heat treatment: a) excess of exogenous phospholipids disintegrates the structure of milk fat globule membrane (MFGM) and b) enzyme molecules denatured partially and their active center became available for exogenous cysteine, molybdenum, hypoxanthine, and nitrate or nitrite.
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Jagannath, A., Manoranjan Kumar, and P. S. Raju. "The recalcitrance of oxalate, nitrate and nitrites during the controlled lactic fermentation of commonly consumed green leafy vegetables." Nutrition & Food Science 45, no. 2 (March 9, 2015): 336–46. http://dx.doi.org/10.1108/nfs-08-2014-0078.
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Purpose – Green leafy vegetables (GLVs) are important components of a balanced diet especially in developing countries where the major requirements of micronutrients are met. However, GLVs also contain significant amounts of oxalate, nitrate and nitrites, whose role in the human diet is constantly changing. The current study explored the behavior of nitrate, nitrites and oxalate in lactic-fermented GLVs with an intention to develop functional foods based on them. Design/methodology/approach – Selected strains of beneficial lactic acid bacteria were used for the controlled fermentation of GLV, while an identical portion was subjected to spontaneous fermentation. The nitrate and nitrites were monitored spectrophotometrically, while oxalate contents were quantified by both titrimetric and by high-performance liquid chromatography throughout the duration of fermentation. Findings – More than 90 per cent of individual constituents studied remained intact in the GLVs paste after the six-day controlled fermentation period. However, there was significant difference between the controlled and spontaneously fermented samples in terms of oxalate, nitrate and nitrite contents. Originality/value – Controlled lactic fermentation although superior in all other aspects may not be able to lower the anti-nutrients present. The advantages of spontaneous fermentation vis-à-vis controlled fermentation are discussed. The work will bring out the importance of the beneficial effects of GLVs and the effect of lactic fermentation.
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Nerdy, Nerdy, and Effendy De Lux Putra. "Spectrophotometric Method for Determination of Nitrite and Nitrate Levels in Broccoli and Cauliflower with Different Fertilization Treatment." Oriental Journal of Chemistry 34, no. 6 (November 13, 2018): 2983–91. http://dx.doi.org/10.13005/ojc/340639.
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Both broccoli and cauliflower are plants that are widely cultivated and consumed. The vegetable also contains Nitrite and Nitrite, which have a negative impact on human health because of the carcinogenic effect. Levels of Nitrite and Nitrate in vegetable are dependent on several factors, one of them is fertilization. The objective of this research is to determine the levels of Nitrite and Nitrate in broccoli and cauliflower without fertilization and with fertilization (natural and chemical). Samples were planted broccoli and cauliflower with different fertilization treatment. Determination of Nitrite and Nitrate levels were done by the colorimetric method (visible spectrophotometric) by using N-(1-Naphthyl) Ethylenediamine Dihydrochloride and Sulfanilic Acid as the dyes and measured at the maximum absorbance wavelength (540 nm) and on the operating time between 11 minutes to 18 minutes. Nitrite and Nitrate levels in various fertilization treatments of broccoli and cauliflower were different significantly. Nitrite and Nitrate levels in broccoli and cauliflower without fertilization are lower than Nitrite and Nitrate levels in broccoli and cauliflower with fertilization. Nitrite and Nitrate levels in broccoli and cauliflower with natural fertilizer fertilization are lower than Nitrite and Nitrate levels in broccoli and cauliflower with chemical fertilizer fertilization.
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Cintya, Henni, Jansen Silalahi, Effendy De Lux Putra, and Rikson Siburian. "The influence of storage condition on nitrite, nitrate and vitamin C levels in vegetables." F1000Research 7 (December 6, 2018): 1899. http://dx.doi.org/10.12688/f1000research.16853.1.
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Vegetables are the main sources of nitrate and nitrite in food. The presence of nitrate and nitrite at a high level may cause a negative impact on health, because nitrite and nitrate when reduced to nitrite, may react with alkylamine to form carcinogenic nitrosamine. The influence of temperature and time of storage on nitrite, nitrate, and vitamin C contents in vegetables were investigated in this study. The vegetables were sweet mustard, bokchoy, spinach and lettuce obtained from a local market. Samples were stored at ±25oC and ±5oC. Analysis of nitrite, nitrate, and vitamin C was conducted in fresh samples, after storage for 24 and 48 hours. Nitrite was analyzed by spectrophotometry at 540 nm. Nitrate reduced into nitrite with Zn in acidic conditions and then analyzed as nitrite. Vitamin C was analyzed by titration with 2.6-dichlorophenolindophenol. During storage, nitrite and nitrate increased, while vitamin C decreased. Nitrite and nitrate content in fresh samples were 15.22 and 22.46 mg/kg (sweet mustard), 12.57 and 6.55 mg/kg (bokchoy), 20.26 and 90.60 mg/kg (spinach), 18.77 and 32.68 mg/kg (lettuce), respectively. Vitamin C content in fresh samples was 101.15 mg/100g (mustard), 92.17 mg/100g (bokchoy), 88.95 mg/100g (spinach), 40.03 mg/100g (lettuce). After storage for 48 hours at ±25oC, nitrite and nitrate increased 44.97% and 53.19% (mustard), 46.18% and 62.59% (bokchoy), 43.86% and 16.48% (spinach), and 41.05% and 47.09% (lettuce), respectively. Vitamin C decreased 67.57% (mustard), 24.68% (bokchoy), 81.25% (spinach), and 79.74% (lettuce). Storage at ±5oC, showed that nitrite and nitrate increased 27.54% and 35.08% (mustard), 13.75% and 43.51% (bokchoy), 19.59% and 10.60% (spinach), 19.85% and 25.16% (lettuce), respectively. Vitamin C decreased 30.88% (mustard), 6.05% (bokchoy), 60.92% (spinach), and 74.94% (lettuce). During storage, nitrite and nitrate increased more significantly at ±25oC than ±5oC while vitamin levels C decreased and were more effective at 25oC than 5oC.
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Cabrera, Elisa, Rafaela González-Montelongo, Teresa Giraldez, Diego Alvarez de la Rosa, and José M. Siverio. "Molecular Components of Nitrate and Nitrite Efflux in Yeast." Eukaryotic Cell 13, no. 2 (December 20, 2013): 267–78. http://dx.doi.org/10.1128/ec.00268-13.
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ABSTRACTSome eukaryotes, such as plant and fungi, are capable of utilizing nitrate as the sole nitrogen source. Once transported into the cell, nitrate is reduced to ammonium by the consecutive action of nitrate and nitrite reductase. How nitrate assimilation is balanced with nitrate and nitrite efflux is unknown, as are the proteins involved. The nitrate assimilatory yeastHansenula polymorphawas used as a model to dissect these efflux systems. We identified the sulfite transporters Ssu1 and Ssu2 as effective nitrate exporters, Ssu2 being quantitatively more important, and we characterize the Nar1 protein as a nitrate/nitrite exporter. The use of strains lacking eitherSSU2orNAR1along with the nitrate reductase geneYNR1showed that nitrate reductase activity is not required for net nitrate uptake. Growth test experiments indicated that Ssu2 and Nar1 exporters allow yeast to cope with nitrite toxicity. We also have shown that the well-knownSaccharomyces cerevisiaesulfite efflux permease Ssu1 is also able to excrete nitrite and nitrate. These results characterize for the first time essential components of the nitrate/nitrite efflux system and their impact on net nitrate uptake and its regulation.
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Sierra-Campos, E., M. A. Valdez-Solana, and M. I. Campos-Almazan. "Nitrate and nitrite in drinking water affect antioxidant enzymes in erythrocytes of rats." Ukrainian Biochemical Journal 90, no. 4 (June 22, 2018): 90–101. http://dx.doi.org/10.15407/ubj90.04.090.
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Albaladejo-Fuentes, Vicente, María-Salvadora Sánchez-Adsuar, James A. Anderson, and María-José Illán-Gómez. "NOx Storage on BaTi0.8Cu0.2O3 Perovskite Catalysts: Addressing a Feasible Mechanism." Nanomaterials 11, no. 8 (August 21, 2021): 2133. http://dx.doi.org/10.3390/nano11082133.
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The NOx storage mechanism on BaTi0.8Cu0.2O3 catalyst were studied using different techniques. The results obtained by XRD, ATR, TGA and XPS under NOx storage–regeneration conditions revealed that BaO generated on the catalyst by decomposition of Ba2TiO4 plays a key role in the NOx storage process. In situ DRIFTS experiments under NO/O2 and NO/N2 show that nitrites and nitrates are formed on the perovskite during the NOx storage process. Thus, it seems that, as for model NSR catalysts, the NOx storage on BaTi0.8Cu0.2O3 catalyst takes place by both “nitrite” and “nitrate” routes, with the main pathway being highly dependent on the temperature and the time on stream: (i) at T < 350 °C, NO adsorption leads to nitrites formation on the catalyst and (ii) at T > 350 °C, the catalyst activity for NO oxidation promotes NO2 generation and the nitrate formation.
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Mével, Genevieve, Claudette Faidy, and Daniel Prieur. "Distribution, activity, and diversity of heterotrophic nitrifiers originating from East Pacific deep-sea hydrothermal vents." Canadian Journal of Microbiology 42, no. 2 (February 1, 1996): 162–71. http://dx.doi.org/10.1139/m96-024.
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Nitrifiers (bacteria, n = 160) were enriched and isolated from samples of hydrothermal waters, sediments, invertebrate tissues, and chimney rocks collected from two East Pacific deep-sea hydrothermal vents (2000 m): the 13°N site and the Guaymas Basin. They were nitrite producers and seemed be widely and uniformly distributed in various parts of hydrothermal ecosystem. These bacteria grew and nitrified better heterotrophically than autotrophically and they possessed characteristics of heterotrophic nitrifiers. All were aerobic, mesophilic gram-negative rods with a unfermentative metabolism and 88% were nitrate reducers or denitrifiers. They were characterized by a high physiological and nutritional diversity, and because of their ability to ammonify, nitrify, and reduce nitrate, they could largely contribute to the nitrogen cycle in hydrothermal sites.Key words: hydrothermal vents, heterotrophic bacteria, nitrifying activity.
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Al-Omari, Ahmed, Bernhard Wett, Ingmar Nopens, Haydee De Clippeleir, Mofei Han, Pusker Regmi, Charles Bott, and Sudhir Murthy. "Model-based evaluation of mechanisms and benefits of mainstream shortcut nitrogen removal processes." Water Science and Technology 71, no. 6 (January 22, 2015): 840–47. http://dx.doi.org/10.2166/wst.2015.022.
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The main challenge in implementing shortcut nitrogen removal processes for mainstream wastewater treatment is the out-selection of nitrite oxidizing bacteria (NOB) to limit nitrate production. A model-based approach was utilized to simulate the impact of individual features of process control strategies to achieve NO−2-N shunt via NOB out-selection. Simulations were conducted using a two-step nitrogen removal model from the literature. Nitrogen shortcut removal processes from two case studies were modeled to illustrate the contribution of NOB out-selection mechanisms. The paper highlights a comparison between two control schemes; one was based on online measured ammonia and the other was based on a target ratio of 1 for ammonia vs. NOx (nitrate + nitrite) (AVN). Results indicated that the AVN controller possesses unique features to nitrify only that amount of nitrogen that can be denitrified, which promotes better management of incoming organics and bicarbonate for a more efficient NOB out-selection. Finally, the model was used in a scenario analysis, simulating hypothetical optimized performance of the pilot process. An estimated potential saving of 60% in carbon addition for nitrogen removal by implementing full-scale mainstream deammonification was predicted.
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Jia, W., and J. A. Cole. "Nitrate and nitrite transport in Escherichia coli." Biochemical Society Transactions 33, no. 1 (February 1, 2005): 159–61. http://dx.doi.org/10.1042/bst0330159.
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Two polytopic membrane proteins, NarK and NarU, are involved in nitrate and nitrite uptake and nitrite extrusion by Escherichia coli. A third polytopic membrane protein, NirC, functions only in nitrite transport. During exponential growth, the quantity of NarU in membrane fractions was <0.01% of the quantity of NarK. During the stationary phase of growth, the ratio of NarU to NarK increased to 0.1%. However, in the exponential phase of growth, the strain expressing only NarK transports and reduces nitrate and nitrite at a rate only slightly higher than that of the strain expressing only NarU, indicating that, in a NarK+ strain, the rate of nitrate reduction is not limited by the rate of nitrate transport. By measuring nitrate and nitrite transport abilities of strains expressing only narK or expressing both narK and nirC, we hypothesized that NarK might function as a primary nitrate–nitrite antiporter. After nitrate is imported by NarK and reduced to nitrite, some nitrite is expelled from the cell and then reimported for reduction to ammonia. Two highly conserved positively charged residues, Arg-87 and Arg-303 of NarU, were shown by site-directed mutagenesis to play a key role in anion transport. This result indicates that NarU might form a single channel for nitrate and nitrite transport.
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Risteska, Keti, and Vladimir M. Petruevski. "Chemistry of Alkali Metals 2 On the Reactions of Alkali Metals with Liquid NO2 and the Nature of the Product." Educación Química 19, no. 2 (June 22, 2011): 142. http://dx.doi.org/10.22201/fq.18708404e.2008.2.25799.
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Las reacciones de sodio y potasio con óxido de nitrógeno(IV) líquido fueron realizadas para confirmar la naturaleza del producto, que fue predicha por Nekrasov (1976) como MNO3 (M = Na, K). Tanto reacciones químicas clásicas como espectrometría FT–IR fueron empleadas durante el análisis. Se demostró que el producto era nitrato, con nitrito como impureza, en ocasiones. Palabras clave: Metales alcalinos, óxido de nitrógeno(IV), dióxido de nitrógeno, tetróxido de dinitrógeno, nitratos alcalinos, nitritos alcalinos, espectrometría IR.
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Petersson, Joel, Mia Phillipson, Emmelie Å. Jansson, Andreas Patzak, Jon O. Lundberg, and Lena Holm. "Dietary nitrate increases gastric mucosal blood flow and mucosal defense." American Journal of Physiology-Gastrointestinal and Liver Physiology 292, no. 3 (March 2007): G718—G724. http://dx.doi.org/10.1152/ajpgi.00435.2006.
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Salivary nitrate from dietary or endogenous sources is reduced to nitrite by oral bacteria. In the acidic stomach, nitrite is further reduced to bioactive nitrogen oxides, including nitric oxide (NO). In this study, we investigated the gastroprotective role of nitrate intake and of luminally applied nitrite against provocation with diclofenac and taurocholate. Mucosal permeability (51Cr-EDTA clearance) and gastric mucosal blood flow (laser-Doppler flowmetry) were measured in anesthetized rats, either pretreated with nitrate in the drinking water or given acidified nitrite luminally. Diclofenac was given intravenously and taurocholate luminally to challenge the gastric mucosa. Luminal NO content and nitrite content in the gastric mucus were determined by chemiluminescence. The effect of luminal administration of acidified nitrite on the mucosal blood flow was also investigated in endothelial nitric oxide synthase-deficient mice. Rats pretreated with nitrate or given nitrite luminally had higher gastric mucosal blood flow than controls. Permeability increased more during the provocation in the controls than in the nitrate- and nitrite-treated animals. Dietary nitrate increased luminal NO levels 50 times compared with controls. Nitrate intake also resulted in nitrite accumulation in the loosely adherent mucous layer; after removal of this mucous layer, blood flow was reduced. Nitrite administrated luminally in endothelial nitric oxide synthase-deficient mice increased mucosal blood flow. We conclude that dietary nitrate and direct luminal application of acidified nitrite decrease diclofenac- and taurocholate-induced mucosal damage. The gastroprotective effect likely involves a higher mucosal blood flow caused by nonenzymatic NO production. These data suggest an important physiological role of nitrate in the diet.
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Lee, Dong Yun, Adela Ramos, Lee Macomber, and James P. Shapleigh. "Taxis Response of Various Denitrifying Bacteria to Nitrate and Nitrite." Applied and Environmental Microbiology 68, no. 5 (May 2002): 2140–47. http://dx.doi.org/10.1128/aem.68.5.2140-2147.2002.
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ABSTRACT The taxis response of Rhodobacter sphaeroides 2.4.1 and 2.4.3, Rhodopseudomonas palustris, and Agrobacterium tumefaciens to nitrate and nitrite was evaluated by observing the macroscopic behavior of cells suspended in soft agar and incubated under various conditions. R. sphaeroides 2.4.3, which is capable of both nitrate and nitrite reduction, showed a taxis response to both nitrate and nitrite. R. sphaeroides 2.4.1, which contains nitrate reductase but not nitrite reductase, did not show a taxis response towards either nitrogen oxide. Insertional inactivation of the nitrite reductase structural gene or its transcriptional regulator, NnrR, in strain 2.4.3 caused a loss of a taxis response towards both nitrate and nitrite. An isolate of 2.4.1 carrying a copy of the nitrite reductase gene from 2.4.3 showed a taxis response to both nitrogen oxides. The taxis response of 2.4.3 was observed under anaerobic conditions, suggesting that the taxis response was due to nitrate and nitrite respiration, not to inhibition of oxygen respiration by respiration of nitrogen oxides. Strain 2.4.3 showed a taxis response to nitrate and nitrite under photosynthetic and aerobic conditions. Changing the carbon source in the culture medium caused an unexpected subtle shift in the taxis response of 2.4.3 to nitrite. A taxis response to nitrogen oxides was also observed in R. palustris and A. tumefaciens. R. palustris exhibited a taxis response to nitrite but not to nitrate, while A. tumefaciens exhibited a response to both compounds.
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Fida, Tekle Tafese, Chuan Chen, Gloria Okpala, and Gerrit Voordouw. "Implications of Limited Thermophilicity of Nitrite Reduction for Control of Sulfide Production in Oil Reservoirs." Applied and Environmental Microbiology 82, no. 14 (May 6, 2016): 4190–99. http://dx.doi.org/10.1128/aem.00599-16.
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ABSTRACTNitrate reduction to nitrite in oil fields appears to be more thermophilic than the subsequent reduction of nitrite. Concentrated microbial consortia from oil fields reduced both nitrate and nitrite at 40 and 45°C but only nitrate at and above 50°C. The abundance of thenirSgene correlated with mesophilic nitrite reduction activity.ThaueraandPseudomonaswere the dominant mesophilic nitrate-reducing bacteria (mNRB), whereasPetrobacterandGeobacilluswere the dominant thermophilic NRB (tNRB) in these consortia. The mNRBThauerasp. strain TK001, isolated in this study, reduced nitrate and nitrite at 40 and 45°C but not at 50°C, whereas the tNRBPetrobactersp. strain TK002 andGeobacillussp. strain TK003 reduced nitrate to nitrite but did not reduce nitrite further from 50 to 70°C. Testing of 12 deposited pure cultures of tNRB with 4 electron donors indicated reduction of nitrate in 40 of 48 and reduction of nitrite in only 9 of 48 incubations. Nitrate is injected into high-temperature oil fields to prevent sulfide formation (souring) by sulfate-reducing bacteria (SRB), which are strongly inhibited by nitrite. Injection of cold seawater to produce oil creates mesothermic zones. Our results suggest that preventing the temperature of these zones from dropping below 50°C will limit the reduction of nitrite, allowing more effective souring control.IMPORTANCENitrite can accumulate at temperatures of 50 to 70°C, because nitrate reduction extends to higher temperatures than the subsequent reduction of nitrite. This is important for understanding the fundamentals of thermophilicity and for the control of souring in oil fields catalyzed by SRB, which are strongly inhibited by nitrite.