Showing papers on "Nitrite published in 1986"
TL;DR: In this paper, the ratio of the 24-h LC50 (concentration lethal to half of the test organisms in 24 h) to the 96-h LCL50 has a median value of 2.0 and is fairly uniform across species.
Abstract: Nitrite, an intermediate in the oxidation of ammonium to nitrate, changes hemoglobin to methemoglobin, which does not carry oxygen; nitrite may thus cause anoxia in fish and other aquatic organisms. The published literature on nitrite toxicity to fish, which consists of about 40 papers, shows that the ratio of the 24-h LC50 (concentration lethal to half of the test organisms in 24 h) to the 96-h LC50 has a median value of 2.0 and is fairly uniform across species; toxicity tests of differing duration can therefore be standardized to a common duration. In general, chronic effects are difficult to detect at concentrations below one-fifth of the 96-h LC50. Most fish concentrate nitrite in fresh water; chloride in the external environment offsets the toxicity of nitrite by competing with nitrite for uptake through the chloride cells of the gills. The strength of the chloride effect is greatest for the least-sensitive species and smallest for the most-sensitive species. The addition of 1 mg/L chloride ...
426 citations
187 citations
TL;DR: Sulfide production was inhibited for periods of at least 6 months and was accompanied by the oxidation of resazurin from its colorless reduced state to its pink oxidized state, which appeared to have a cytotoxic effect on sulfate-reducing populations.
Abstract: The addition of 59 mM nitrate inhibited biogenic sulfide production in dilute sewage sludge (10% [vol/vol]) amended with 20 mM sulfate and either acetate, glucose, or hydrogen as electron donors Similar results were found when pond sediment or oil field brines served as the inoculum Sulfide production was inhibited for periods of at least 6 months and was accompanied by the oxidation of resazurin from its colorless reduced state to its pink oxidized state Lower amounts of nitrate (6 or 20 mM) and increased amounts of sewage sludge resulted in only transient inhibition of sulfide production The addition of 156 mM sulfate to bottles with 59 mM nitrate and 10% (vol/vol) sewage sludge or pond sediment resulted in sulfide production Nitrate, nitrite, and nitrous oxide were detected during periods where sulfide production was inhibited, whereas nitrate, nitrite, and nitrous oxide were below detectable levels at the time sulfide production began The oxidation of resazurin was attributed to an increase in nitrous oxide which persisted in concentration of about 10 mM for up to 5 months The numbers of sulfate-reducing organisms decreased from 106 CFU ml−1 sludge to less than detectable levels after prolonged incubation of oxidized bottles The addition of 10 mM glucose to oxidized bottles after 145 weeks of incubation resulted in rereduction of the resazurin and subsequent sulfide production The prolonged inhibition of sulfide production was attributed to an increase in oxidation-reduction potential due to biogenic production of nitrous oxide, which appeared to have a cytotoxic effect on sulfate-reducing populations
157 citations
TL;DR: In this paper, the feasibility of removing nitrogen from highly nitrogenous wastewater by blocking the nitrification process at the intermediary nitrite level through the action of free ammonia and subsequently reducing the nitrite to nitrogen gas was demonstrated.
Abstract: The objective of this long-term research project was to demonstrate the feasibility of removing nitrogen from highly nitrogenous wastewater by (a) blocking the nitrification process at the intermediary nitrite level through the action of free ammonia and (b) subsequently reducing the nitrite to nitrogen gas. The success of such a process could lead to substantial reductions in nitrogen removal costs.Two identical bench-scale activated sludge systems were operated for 147 days, in the initial phase. Each system was composed of four equal-sized, completely mixed cells in series. The free ammonia concentration was highest in the first cell of each system. It averaged 2 mg NH3-N/L in the first system and 5 mg NH3-N/L in the second. Nitrite buildup, in excess of 80% of the oxidized nitrogen present, was induced and sustained for around 2 months in all cells of the second system, after which time a steady decline occurred. Nitrite buildup could not be sustained in the first system. Average chemical oxygen deman...
156 citations
TL;DR: In this paper, the relationship between rate of chloride uptake and external chloride concentration was investigated in Rainbow trout,Salmo gairdneri, and Perch,Perca fluviatilis.
Abstract: 1.
The relationship between rate of chloride uptake and external chloride concentration was investigated in Rainbow trout,Salmo gairdneri, and Perch,Perca fluviatilis. The relationship between nitrite uptake and external nitrite and the inhibition of chloride uptake by nitrite was also investigated. Nitrite tolerance tests were performed on a variety of freshwater animals, including Carp,Cyprinus carpio, Tench,Tinca tinca, Pike,Esox lucius, Eel,Anguilla anguilla, and tadpoles,Rana temporaria.
2.
The chloride uptake mechanism is saturable, with maximum uptake rates of 368 μMh−1kg−1 and 429 μMh−1kg−1 for the trout and perch, respectively. The half saturation value (Km, the affinity constant) is 159 μMl−1 for trout and 333 μMl−1 for perch.
3.
Net nitrite transport was determined in trout, net movement being into the fish against a concentration gradient, with a maximum uptake rate of 281 μMh−1kg−1; theKm is 198 μMl−1. This suggests that nitrite enters the fish via an active uptake process.
4.
The data suggest that nitrite is a simple competitive inhibitor of active chloride uptake in both trout and perch. Trout are less tolerant of nitrite than perch (24-h LC50 values are 0.7 mMl−1 for trout and 1.2 mM l−1 for perch) and also have a greater affinity for nitrite.
5.
The spectrum of nitrite sensitivity seen in freshwater animals is discussed in relation to chloride uptake kinetics. These data support the hypothesis that nitrite uptake is an active process and furthermore uptake is linked quantitatively with chloride uptake, suggesting that chloride and nitrite enter the fish via the same route.
149 citations
TL;DR: The total concentration and redox state of iron were examined along a transect across the continental shelf off the Peruvian coast during. January 1984 as discussed by the authors, where the total and dissolved iron (0.4~pm filter) were measured by the Co-APDC coprecipitation method.
Abstract: The total concentration and redox state of iron were examined along a transect across the continental shelf off the Peruvian coast during. January 1984. Total and dissolved iron (0.4~pm filter) were measured by the Co-APDC coprecipitation method. Fe(II) was measured by a preconcentration step with S-hydroxyquinoline bonded to silica as the stationary phase, followed by elution and the ferrozine method. Up to 40 nmol kg-l of Fe(II) was detected in the bottom water at 5-10 km offshore and decreased markedly upward in the water column and with distance offshore. A good correlation between the distribution of Fe(II) and nitrite in the bottom water indicated a common source from the shelf sediments. Elevated Fe(II) concentrations near the sea surface and a diel change were probably due to photochemical reactions involving iron. Total iron levels were >300-500 nmol kg-’ in the surface and the bottom water at 5-6 km offshore. About 80-90% of the iron was in the particulate form, indicating a substantial input of iron from continental dust and from the sediments on the shelf. The total iron level decreased considerably within 35 km of the coastline and the iron seemed to be trapped on the shelf. Iron is found in natural waters in both Fe(II) and Fe(III) oxidation states. The distribution of these two forms of iron is governed by several factors, including redox potential, pH, and the presence of organic material. From thermodynamic considerations, the concentration of reduced forms of iron in oxic natural waters will be much lower than that of the oxidized forms of iron due to the rapid oxidation of Fe(II) by Oz. Nevertheless, it has been suggested that nonequilibrium processes may enable Fe(II) species to persist at appreciable concentrations in natural waters even in the presence of oxygen. McMahon (1969) suggested that annual and diurnal variations of acid-soluble ferrous iron in lake water were a result of photochemical reactions or of metabolic activity of microorganisms. Recently, the photochemistry of iron in natural waters has been emphasized by several studies as reviewed by Zafiriou ( 1983). Miles and Brezonik (198 1) showed that the oxygen consumption in humic-colored freshwaters involved a photochemical ferrous-ferric catalytic cycle. Waite and Morel (1984)
145 citations
Journal Article•
135 citations
TL;DR: Two of nine sulfate reducing bacteria tested, Desulfobulbus propionicus and Desulfovibrio desulfuricans (strain Essex 6), were able to grow with nitrate as terminal electron acceptor, which was reduced to ammonia.
Abstract: Two of nine sulfate reducing bacteria tested,Desulfobulbus propionicus andDesulfovibrio desulfuricans (strain Essex 6), were able to grow with nitrate as terminal electron acceptor, which was reduced to ammonia.
118 citations
TL;DR: It is suggested that nitrification in this soil is a heterotrophic process catalyzed by acid-tolerant fungi and not by autotrophs or heterOTrophs in nonacid microsites.
Abstract: Nitrate was formed from ammonium at pH 3.2 to 6.1 in suspensions of a naturally acid forest soil; the maximum rates of formation occurred at ca. pH 4 to 5. Nitrate was also formed from soil nitrogen in suspensions incubated at 50 degrees C. Autotrophic nitrifying bacteria could not be isolated from this soil. Enrichment cultures produced nitrate in a medium with beta-alanine if much soil was added to the medium, and nitrite but not nitrate was formed in the presence of small amounts of soil. Nitrification by these enrichments was abolished by eucaryotic but not procaryotic inhibitors. A strain of Absidia cylindrospora isolated from this soil was found to produce nitrate and nitrite in a medium with beta-alanine at pH values ranging from 4.0 to 4.8. Nitrate production by A. cylindrospora required the presence of sterile soil. Free and bound hydroxylamine, hydroxamic acids, and primary aliphatic nitro compounds did not accumulate during the conversion of beta-alanine to nitrite by the fungus. The organism also formed nitrite from ammonium in a medium containing acetate. We suggest that nitrification in this soil is a heterotrophic process catalyzed by acid-tolerant fungi and not by autotrophs or heterotrophs in nonacid microsites.
112 citations
TL;DR: The absolute rate constants for the reaction of NO32˙ (formed by one-electron reduction of nitrate) with oxygen, benzoquinone, and methyl viologen have been determined by pulse radiolysis as discussed by the authors.
Abstract: The absolute rate constants for the reaction of NO32–˙(formed by one-electron reduction of nitrate) with oxygen, benzoquinone, and methyl viologen have been determined by pulse radiolysis. Experiments have shown that such reactions can occur in competition with the hydrolysis reaction leading to NO2˙ and that the formation of the latter can be catalysed by the presence of hydrogen or ammonium ions. Absolute rate constants for the oxidation of the phenothiazine derivative metiazinic acid, of 2,2′-azinobis-(3-ethyl-2,3-dihydrobenzothiazole-6-sulphonate), of ascorbate, and of dihydroxyfumarate by NO2˙ have also been measured.
111 citations
TL;DR: In this article, the synthesis of aquocyanocobalt(III)-hepta(2-phenylethyl)-cobyrinate is described, which is a more lipophilic substitute for a previously reported nitrite-carrier.
TL;DR: Application of the method to analysis of a milk sample was tested with aliquots spiked with known amounts of nitrite, with the detection limit approximately 0.5 ng ml in the test sample (1% relative fluorescence intensity).
TL;DR: In this paper, the rate of ammonia biooxidation to nitrite by an autotrophic culture of nitrifiers was evaluated using the Michaelis-Menten-type relationship.
TL;DR: Functional activity of the colonic mucosa, judged by bicarbonate output, was impaired in all subjects with measurable nitrite levels in UC and detection of nitrite in acute colitis suggests impaired oxidation of nitrites to nitrate in the coloni mucosa or impaired luminal reduction of Nitrite to NH4 by bacteria.
Abstract: In the healthy colon, sodium nitrite stimulates mucosal metabolism of short-chain fatty acids and absorption of ions, both functions that are impaired in the mucosa of patients with ulcerative colitis
TL;DR: In this paper, the authors propose a reduction method based on Oxydation electrochimique de [(tpy)(bpy)M(NH 3 )] 2+ et reduction de [tpy]-bpy M(NO 2 )] +
Abstract: Oxydation electrochimique de [(tpy)(bpy)M(NH 3 )] 2+ et reduction de [(tpy)(bpy) M(NO 2 )] +
TL;DR: A simple, sensitive, and reproducible fluorometric method for determination of nitrite has been developed based on the nitrosation of 4-Hydroxycoumarin in acidic medium and subsequent reduction to 3-amino-4-hydroxy-cou marin, which is fluorescent in alkaline medium.
Abstract: A simple, sensitive, and reproducible fluorometric method for determination of nitrite has been developed. This method is based on the nitrosation of 4-hydroxycoumarin in acidic medium and subsequent reduction to 3-amino-4-hydroxy-coumarin, which is fluorescent in alkaline medium. The fluorescence intensity is proportional to the nitrite concentration in the range of 3 ng/mL to 1 ..mu..g/mL in the sample solution, with a relative standard deviation of 0.5% (50 ng/mL). The method has been applied to the determination of nitrite in saliva.
TL;DR: In this article, the ability of Halobacterium vallismortis, H. mediterranei and H. marismortui to grow anaerobically and denitrify was determined.
Abstract: The ability of Halobacterium vallismortis, Halobacterium mediterranei and Halobacterium marismortui (Ginzburg strain) to grow anaerobically and denitrify was determined. Each organism grew anaerobically only in the presence of nitrate. H. marismortui produced nitrite and dinitrogen from nitrate during exponential growth. However, as the culture entered stationary phase, dinitrogen production ceased and nitrous oxide was detected. H. vallismortis produced nitrous oxide and dinitrogen during exponential growth, with dinitrogen production ceasing at the onset of stationary phase. H. mediterranei produced dinitrogen during exponential growth and did not produce nitrous oxide. These results confirm the occurrence of denitrification in the halobacteria.
TL;DR: The results indicate that although the ability of strain FBA 20a to reduce nitrate is a physiologically significant process, it is a specialized property of only a few strains of Desulfovibrio isolates.
Abstract: Rates of nitrate and nitrite reduction by cultures and washed suspensions of both natural isolates and culture collection strains of sulphate-reducing bacteria have been determined. Neither activity was detected in the Desulfotomaculum strains, but all Desulfovibrio strains reduced nitrite. Only the Desulfovibrio natural isolate FBA 20a was also able to reduce nitrate. Nitrate reduction by washed suspensions of strain FBA 20a was far more rapid than previously reported rates for sulphate-reducing bacteria [6.6 μmol NO
3
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reduced h-1 (mg dry weight)-1] and was regulated by nitrate induction and sulphate repression: it was insensitive to the product of nitrate reduction, ammonium ions. Cell yields from sulphate-limited cultures were proportional to the concentration of nitrate added with a yield coefficient of 28.0 g bacterial dry weight per mol of nitrate reduced. These results indicate that although the ability of strain FBA 20a to reduce nitrate is a physiologically significant process, it is a specialized property of only a few strains of Desulfovibrio isolates.
TL;DR: Anaerobic cytochrome c552 was purified to electrophoretic homogeneity by ion-exchange chromatography and gel filtration from a mutant of Escherichia coli K 12 that synthesizes an increased amount of this pigment.
Abstract: Anaerobic cytochrome c552 was purified to electrophoretic homogeneity by ion-exchange chromatography and gel filtration from a mutant of Escherichia coli K 12 that synthesizes an increased amount of this pigment. Several molecular and enzymatic properties of the cytochrome were investigated. Its relative molecular mass was determined to be 69 000 by sodium dodecyl sulfate/polyacrylamide gel electrophoresis. It was found to be an acidic protein that existed in the monomeric form in the native state. From its heme and iron contents, it was concluded to be a hexaheme protein containing six moles of heme c/mole protein. The amino-acid composition and other properties of the purified cytochrome c552 indicated its similarity to Desulfovibrio desulfuricans hexaheme cytochrome. The cytochrome c552 showed nitrite and hydroxylamine reductase activities with benzyl viologen as an artificial electron donor. It catalyzed the reduction of nitrite to ammonia in a six-electron transfer. FMN and FAD also served as electron donors for the nitrite reduction. The apparent Michaelis constants for nitrite and hydroxylamine were 110 microM and 18 mM, respectively. The nitrite reductase activity of the cytochrome c552 was inhibited effectively by cupric ion and cyanide.
TL;DR: In this paper, the conversion of substantial amounts of ammonia nitrogen into organic nitrogen as a direct result of nitrification at neutral pH-values, was monitored in soil suspensions amended with ammonium nitrogen.
Abstract: The conversion of substantial amounts of ammonia nitrogen into organic nitrogen as a direct result of nitrification at neutral pH-values, was monitored in soil suspensions amended with ammonium nitrogen. The influence of the chemolithotrophic nitrifying bacteria was verified by applying nitrapyrin as a selective inhibitor in control experiments. In addition, the role of phenolic compounds was examined by adding α naphthol. The factors influencing the nitrification processi.e. pH, NH4+−N, NO2−−N, NO3−−N were measured during a 60 days incubation period. Nitrification started to be active after 5 and 10 days in the normal and the naphthol spiked soil suspensions respectively; it was inhibited in the nitrapyrin controls. Parallel with nitrification, formation of organic nitrogen was observed. The humic matter fractions were extracted and analyzed by I.R. spectroscopy which revealed the valence vibration ranges of nitro and nitroso groups fixed in different positions on aromatic compounds, both for normal and naphthol spiked samples. High resolution gas chromatography combined with mass spectroscopic analysis indicated the formation of nitrosonaphtholes. In addition a novel organic nitro compound was identifiedi.e. an azido nitro benzene. No nitrogen was fixed in the samples treated with nitrification inhibitor. A mechanism for the fixation of nitrite nitrogen during nitrification is proposed.
TL;DR: Halobacterium Denitrificans was one of several carbohydrate-utilizing, denitrifying, extremely halophilic bacteria isolated by anaerobic enrichment in the presence of nitrate.
Abstract: Halobacterium denitrificans was one of several carbohydrate-utilizing, denitrifying, extremely halophilic bacteria isolated by anaerobic enrichment in the presence of nitrate. Anaerobic growth took place only when nitrate (or nitrite) was present and was accompanied by the production of dinitrogen. In the presence of high concentrations of nitrate (i.e., 0.5 percent), nitrous oxide and nitrite were also detected. When grown aerobically in a mineral-salts medium containing 0.005 percent yeast extract, H. denitrificans utilized a variety of carbohydrates as sources of carbon and energy. In every case, carbohydrate utilization was accompanied by acid production.
TL;DR: Results indicate that plasma nitrite concentrations are the primary determinant of the toxicity of nitrite to fishes and depend on the discriminatory ability of the active transport system in fish gills which ordinarily transports chloride ions.
TL;DR: Of 31 compounds tested, 22 were mutagenic after nitrite treatment, comparable with those of benzo[alpha]pyrene, 3-methylcholanthrene and 2-amino-9H-pyrido[2,3-b]indole (A alpha C) (Sugimura, 1982).
Abstract: Indole and 7-derivatives, L- and D-tryptophan and 9 derivatives, and beta-carboline (norharman) and 11 derivatives were tested for mutagenicity to Salmonella typhimurium TA100 and TA98 after nitrite treatment. 1-Methylindole, which is present in cigarette smoke condensate (Grob and Voellmin, 1970; Hoffmann and Rathkamp, 1970), was the most mutagenic to TA100 without S9 mix after nitrite treatment, inducing 615,000 revertants/mg. 2-Methylindole, 1-methyl-DL-tryptophan, harmaline and (-)-(1S,3S)-1,2-dimethyl-1,2,3,4-tetrahydro-beta-carboline-3- carboxylic acid also showed strong mutagenicity after nitrite treatment, inducing 129,000, 184,000, 103,000 and 197,000 revertants/mg, respectively. These mutagenic potencies were comparable with those of benzo[alpha]pyrene, 3-methylcholanthrene and 2-amino-9H-pyrido[2,3-b]indole (A alpha C) (Sugimura, 1982). Of 31 compounds tested, 22 were mutagenic after nitrite treatment. Since various indole compounds are ubiquitous in our environment, especially in plants, the presence of their mutagenicities after nitrite treatment warrants further studies, including those on their in vivo carcinogenicities.
TL;DR: It is concluded that the effects of sulfite or nitrite on ATP, ADP and inorganic phosphate are the result of inhibition of glyceraldehyde-3-phosphate dehydrogenase and not of inhibited phosphorylation processes in the mitochondria.
Abstract: After addition of 5 mM sulfite or nitrite to glucose-metabolizing cells of Saccharomyces cerevisiae a rapid decrease of the ATP content and an inversely proportional increase in the level of inorganic phosphate was observed. The concentration of ADP shows only small and transient changes. Cells of the yeast mutant pet 936, lacking mitochondrial F1ATPase, after addition of 5 mM sulfite or nitrite exhibit changes in ATP, ADP and inorganic phosphate very similar to those observed in wild type cells. They key enzyme of glucose degradation, glyceraldehyde-3-phosphate dehydrogenase was previously shown to be the most sulfiteor nitrite-sensitive enzyme of the glycolytic pathway. This enzyme shows the same sensitivity to sulfite or nitrite in cells of the mutant pet 936 as in wild type cells. It is concluded that the effects of sulfite or nitrite on ATP, ADP and inorganic phosphate are the result of inhibition of glyceraldehyde-3-phosphate dehydrogenase and not of inhibition of phosphorylation processes in the mitochondria. Levels of GTP, UTP and CTP show parallel changes to ATP. This is explained by the presence of very active nucleoside monophosphate kinases which cause a rapid exchange between the nucleoside phosphates. The effects of the sudden inhibition of glucose degradation by sulfite or nitrite on levels of ATP, ADP and inorganic phosphate are discussed in terms of the theory of Lynen (1942) on compensating phosphorylation and dephosphorylation in steady state glucose metabolizing yeast.
TL;DR: The effect of salt concentration in combination with sodium nitrite on growth of mixed strains of Salmonella and enteropathogenic E. coli at three pH values and storage temperatures is reported, finding E.E. coli tended to be more tolerant of salt and nitrite thanSalmonella.
TL;DR: The nitrate-nitrate exchange reaction suggests the existence of an oxygen derivative of a H2O-utilizing oxidoreductase, and is seen to be the source of O in nitrate produced by oxidation of nitrite by N. winogradskyi.
TL;DR: The amount of nitrates excreted in urine consistently exceeded intakes of nitrate and nitrite by an average 870 mumol/day, which represented endogenous synthesis by subjects and was not due to unmeasured nitrate in the diet.
TL;DR: The mechanism of the denitrification and nitrosation reactions catalyzed by the heme cd-containing nitrite reductase from Pseudomonas stutzeri JM 300 has been studied with whole cell suspensions using H2(18)O, 15NO, and 15NO-2.
TL;DR: In this article, the reduction catalytique de NO 3 − en NH 3 avec une electrode de carbone modifiee is described. But this is not the case in this paper.
Abstract: Donnees sur la reduction catalytique de NO 3 − en NH 3 avec une electrode de carbone modifiee