Ammonium Nitrate Medium Research Articles

N,S-containing soft ligands for extractive separation of f-metals: synthesis and unexpected inverse selectivity

A number of heterocycle-based bis(phosphine sulfides) have been synthesized from the corresponding phosphine oxides using phosphorus(v) sulfide in good to excellent yields, for one representative compound the molecular structure has been determined by single crystal X-ray diffraction. The compounds obtained were tested as extractants for f-metals both in nitric acid and ammonium nitrate media, distribution coefficients and selectivity factors have been determined for an Am/Eu pair.

Direct bio-utilization of untreated rapeseed meal for effective iturin A production by Bacillus subtilis in submerged fermentation.

The feasibility of using untreated rapeseed meal as a nitrogen source for iturin A production by Bacillus subtilis 3–10 in submerged fermentation was first evaluated by comparison with two different commercial nitrogen sources of peptone and ammonium nitrate. A significant promoting effect of rapeseed meal on iturin A production was observed and the maximum iturin A concentration of 0.60 g/L was reached at 70 h, which was 20% and 8.0 fold higher than that produced from peptone and ammonium nitrate media, respectively. It was shown that rapeseed meal had a positive induction effect on protease secretion, contributing to the release of soluble protein from low water solubility solid rapeseed meal for an effective supply of available nitrogen during fermentation. Moreover, compared to raw rapeseed meal, the remaining residue following fermentation could be used as a more suitable supplementary protein source for animal feed because of the great decrease of major anti-nutritional components including sinapine, glucosinolate and its degradation products of isothiocyanate and oxazolidine thione. The results obtained from this study demonstrate the potential of direct utilization of low cost rapeseed meal as a nitrogen source for commercial production of iturin A and other secondary metabolites by Bacillus subtilis.

On the mechanism(s) of membrane permeability transition in liver mitochondria of lamprey, Lampetra fluviatilis L.: insights from cadmium.

Previously we have shown that opening of the mitochondrial permeability transition pore in its low conductance state is the case in hepatocytes of the Baltic lamprey (Lampetra fluviatilis L.) during reversible metabolic depression taking place in the period of its prespawning migration when the exogenous feeding is switched off. The depression is observed in the last year of the lamprey life cycle and is conditioned by reversible mitochondrial dysfunction (mitochondrial uncoupling in winter and coupling in spring). To further elucidate the mechanism(s) of induction of the mitochondrial permeability transition pore in the lamprey liver, we used Cd2+ and Ca2+ plus Pi as the pore inducers. We found that Ca2+ plus Pi induced the high-amplitude swelling of the isolated “winter” mitochondria both in isotonic sucrose and ammonium nitrate medium while both low and high Cd2+ did not produce the mitochondrial swelling in these media. Low Cd2+ enhanced the inhibition of basal respiration rate of the “winter” mitochondria energized by NAD-dependent substrates whereas the same concentrations of the heavy metal evoked its partial stimulation on FAD-dependent substrates. The above changes produced by Cd2+ or Ca2+ plus Pi in the “winter” mitochondria were only weakly (if so) sensitive to cyclosporine A (a potent pharmacological desensitizer of the nonselective pore) added alone and they were not sensitive to dithiothreitol (a dithiol reducing agent). Under monitoring of the transmembrane potential of the “spring” lamprey liver mitochondria, we revealed that Cd2+ produced its decrease on both types of the respiratory substrates used that was strongly hampered by cyclosporine A, and the membrane potential was partially restored by dithiothreitol. The effects of different membrane permeability modulators on the lamprey liver mitochondria function and the seasonal changes in their action are discussed.

Abstract 104: Effects of Pinacidil and Ca 2 + on Sodium-loaded Rat Heart Mitochondria

Deterioration of the contractile parameters of the heart muscle caused by ischemia and followed reperfusion is known as the main postoperative complication which is related to Ca 2+ and Na + overload in cardiomyocytes and mitochondria. Pinacidil reduced the overload in ischemia/reperfusion experiments. The mechanism of this phenomenon is still not clear. We hypothesized that increased ion permeability of the inner mitochondrial membrane (IMM) followed drop of electrochemical potential (ΔΨ mito ) can reduce the calcium. The aim of the study was to elucidate the effect of pinacidil (100 μM) and Ca 2+ (100 μM ) on swelling, oxygen consumption and ΔΨ mito of isolated sodium-loaded rat heart mitochondria (RHM(Na)) energized glutamate and malate. Pinacidil significantly enchanced the permeability of IMM to protons in ammonium nitrate medium. Also increased swelling of RHM(Na) energized with substrates in potassium acetate medium revealed that pinacidil increased potassium transport into matrix. Pinacidil stimulated oxygen consumption of RHM(Na) in State 4 and detained Ca 2+ -induced dissipation of ΔΨ mito . Under condition of Ca 2+ and Na + overload simulating ischemia/reperfusion, RHM(Na) oxygen consumption was not affected with pinacidil in State 3 and in the presence of 2,4-dinitrophenol. Cyclosporin A and ADP, the inhibitors of mitochondrial permeability transition pore (MPTP), markedly decreased Ca 2+ - induced swelling of RHM(Na) in nitrate ammonium or potassium acetate medium in the presence of pinacidil. Carboxyatractyloside, an inhibitor of cytosolic side-specific adenine nucleotide translocase, eliminated a pinacidil-stimulated oxygen consumption of succinate-energized RHMNa in State 4 regardless of the presence of Ca 2+ . Pinacidil was also concluded to accelerat potassium flux into energized RHM(Na) and promot MPTP opening in the low conduction state. Based on our data we suggested that the effect of pharmacological preconditioning induced by pinacidil could be due to it’s direct effect on mitochondria which is connected with above stimulation of the potassium permeability of the inner mitochondrial membrane and following reduce of the ΔΨ mito that thus prevent calcium overload of cardiomyocytes after ischemia/reperfusion in turn.

Influence of trophic conditions on exopolysaccharide production: bacterial biofilm susceptibility to chlorine and monochloramine.

This study examines the controversial efficacy of chlorine and monochloramine against biofilms that differ in their extracellular polysaccharide (EPS) content. The results point out a net variability of bacterial biofilm susceptibility according to the nutrients present. Chlorine and monochloramine showed an equal biocidal activity on lactose medium-grown E. coli ATCC 10536 and glycerol-ammonium nitrate medium-grown nonmucoid Pseudomonas aeruginosa biofilms. In contrast, the effect of monochloramine is greater compared with that of chlorine on E. coli and mucoid P. aeruginosa biofilms grown in sucrose and glycerol-ammonium nitrate media, respectively. In these culture conditions, treatment with 25 mg monochloramine/L for 2 h reduced culturable cells by 4.5 logs (99.997%) for E. coli and about 3 logs (99.87%) for mucoid P. aeruginosa while the similar treatment with chlorine reduced culturable cells in these biofilms by 2.2 logs (99.4%) and 1 log (10%), respectively. The decrease of chlorine disinfection efficacy on sucrose and glycerol-ammonium nitrate medium-grown biofilms is postulated to be linked to the higher polysaccharide production observed in these media. It seems likely that monochloramine produces a high leakage of material absorbing at 260 nm from sucrose medium-grown E. coli biofilm, which could indicate its better penetration into biofilms.

Isolation and characterization of two new negative regulatory mutants for nitrate assimilation in Chlamydomonas reinhardtii obtained by insertional mutagenesis.

Plasmid DNA carrying either the nitrate reductase (NR) gene or the argininosuccinate lyase gene as selectable markers and the corresponding Chlamydomonas reinhardtii mutants as recipient strains have been used to isolate regulatory mutants for nitrate assimilation by insertional mutagenesis. Identification of putative regulatory mutants was based on their chlorate sensitivity in the presence of ammonium. Among 8975 transformants, two mutants, N1 and T1, were obtained. Genetic characterization of these mutants indicated that they carry recessive mutations at two different loci, named Nrg1 and Nrg2. The mutation in N1 was shown to be linked to the plasmid insertion. Two copies of the nitrate reductase plasmid, one of them truncated, were inserted in the N1 genome in inverse orientation. In addition to the chlorate sensitivity phenotype in the presence of ammonium, these mutants expressed NR, nitrite reductase and nitrate transport activities in ammonium-nitrate media. Kinetic constants for ammonium (I4C-methylammonium) transport, as well as enzymatic activities related to the ammonium-regulated metabolic pathway for xanthine utilization, were not affected in these strains. The data strongly suggest that Nrg1 and Nrg2 are regulatory genes which specifically mediate the negative control exerted by ammonium on the nitrate assimilation pathway in C. reinhardtii.

Spannungsrißkorrosion niedriglegierter Chromstähle in Nitratlösungen

The stress-corrosion cracking (SCC) behaviour of a low-alloy (0.07% C-2.0 % Cr) steel in nitrate media (5M NH 4 NO 3 ) has been studied using the slow strain rate method in combination with potential sweep measurements, metallographic microscopy and SEM observations. It is found that the steel undergoes intergranular SCC in ammonium nitrate media with pH 1 to 7 and temperature above 50 °C in a wide potential range ( -1,0 up to +0.8 V, SCE). The highest susceptibility to SCC, however, occurs at potentials in the region of active to passive transition of the steel. The low alloying with Cr, although with a favourable effect on SCC resistance, does not change significantly the SCC behaviour of low-carbon steels in hot nitrate environments.

Stimulation of dark carbon fixation in rice and tomato roots by application of ammonium nitrogen

Abstract Dark carbon fixation was investigated in roots of rice plants, an ammonium-tolerant species and tomato plants, an ammonium-sensitive one during periods of growth on nutrient media containing ammonium, ammonium nitrate, or nitrate as the nitrogen source. Application of ammonium nitrogen immediately stimulated the dark carbon fixation in the roots of both plants. The stimulation was greater in the plants grown on ammonium media than in those grown on ammonium nitrate media. The increase in the rates of dark carbon fixation continued in rice plants for 7 d whereas in tomato plants the rates reached the maximum value at day 1, and then gradually decreased. Most of the 14C fixed for 3 h remained in the roots: 75–90% in rice plants and 65–80% in tomato roots. Soluble fixation products were composed of amino acids and organic acids. Organic acids were more labelled than amino acids. Amino acids were more labelled in both plants grown on ammonium and ammonium nitrate media than in those grown on nitrate ...

Synthetic Inorganic Ion-Exchange Materials. XXXXVI. Ion-Exchange Behavior of Titanium(IV) Antimonate Cation Exchanger for Alkali Metal Ions in Ammonium Nitrate Media

Abstract Titanium(IV) antimonate (TiSbA) showed an extremely high selectivity for lithium ions in ammonium nitrate media, the increased selectivity order for microamounts being Rb+<Na+<Cs+<K+<<Li+. The selective separation of lithium ions from other alkali metal ions can be achieved on small columns of TiSbA by a mixed solution of nitric acid and ammonium nitrate.

Synthesis of methylisoamylnitrosamine from isoamylamine by fungi (Fusarium moniliforme).

Methylisoamylnitrosamine, a carcinogenic N-nitroso compound, has been formed in glucose ammonium nitrate medium containing 150 mg of isoamylamine (a primary amine) inoculated with a common fungus (Fusarium moniliforme Sheldon), to which 400 mg NaNO2 are added after incubation for 7-8 days at 28 degrees C. No such compound has been found in control samples without fungi or isoamylamine. This paper reports a method of experimental synthesis of the nitrosamine by F. moniliforme strains 82-01 and 83-01, using isoamylamine and NaNO2, as well as the analysis of the compound by GC/MS and GC/TEA.

The Synergistic Extraction of Sm(NO3)3and Gd(NO3)3by a Mixture of Tributyl Phosphate and Aliquat 336 in AMSCO and Ammonium Nitrate Medium

Abstract The synergic extraction of Sm and Gd using a mixture of tri-butyl phosphate and Aliquat 336 is presented. The influence of diluents, salting out agents and acidity on the synergic extractions have been investigated. The separation factor of Sm and Gd was found to be larger than 3. This is one of the best systems for the separation of Sm and Gd. NH4NO3 was found to be extracted by pure TBP or pure Aliquat 336, but cannot be extracted by a mixture of TBP and Aliquat 336.

Ion-exchange selectivities of amorphous and anatase-types hydrous titanium dioxides and the possible separation of bivalent transition metal ions

Amorphous and anatase-type hydrous titanium dioxides showed typical amphoteric ion-exchange properties. The ion-exchange selectivity for bivalent transition metal ions was studied as a function of both pH and metal ion concentration in ammonium nitrate media. The selectivity series was Co<Ni<Mn<Zn<Cd<Cu for the amorphous and Ni<Co<Mn<Zn<Cd<Cu for the anatase-type material. The separation factor on the anatase-type material is larger than on the amorphous material. Effective group separation of Co−Ni and Zn−Cd−Cu could be achieved on an ion-exchange column containing the anatase-type hydrous titanium dioxide.

Sporulation of Aspergillus niger in submerged liquid culture.

SUMMARY: Asexual sporulation of Aspergillus niger occurred in submerged culture in a liquid minimal medium without added nitrogen, in low ammonium-N concentrations, and in a wide range of nitrate-N concentrations. Ammonium salts containing more than 48 mg. atom N/l. were inhibitory to conidiation. Most amino acids overcame the ammonium inhibition of conidiation when added to an ammonium nitrate medium. Glyoxylate and several intermediates of the tricarboxylic acid (TCA) cycle also promoted conidiation in the presence of ammonium. Changes in the medium of conidiating and non-conidiating cultures were examined with respect to nitrogen and glucose concentrations, dry weight and pH value. The activities of two glutamate dehydrogenases, one requiring NAD and the other specific for NADP, and of aspartate and alanine amino transferases varied during growth as a function of the stage of the life cycle and of the growth medium. There was no clear correlation between the activities of these enzymes and conidiation of this fungus.

Control of nitrate reductase by iron in Neurospora crassa

Iron deficiency has been found to occur in Neurospora crassa grown in sole nitrate medium, even when levels of iron, normal with respect to the usual ammonium nitrate medium, were provided. Under this condition, mycelial nitrate reductase and catalase levels were high, there was inhibition of growth, and there was accumulation of an iron-binding compound and nitrite in the culture filtrate. These were counteracted by increasing the iron level of the sole nitrate medium, except that the catalase level increased still further. Evidence is presented for the control of nitrate reductase by iron.

Studies on growth response of some pathogenic species of Phyllosticta in different nitrogen media

Summary The growth response of twelve species Phyllosticta was studied on eighteen different nitrogen sources. Amongst the nitrates, potassium nitrate was a very good source while ammonium nitrate was much inferior. Ammonium sulphate was a very poor source. None of the Phyllosticta species were capable of utilizing sodium nitrite. Most of the organic nitrogen substances like glycine, DL-alanine, L-glutamic acid, DL-aspartic acid, DL-valine, L-proline, asparagine and glutamine were invariably good sources. The value of L-arginine and DL-phenylalanine were variable for these isolates of Phyllosticta . L-histidine as well as two sulphur containing amino acids viz., L-cystine and DL-methionine were poor sources for all the present species. Varying pH patterns were recorded on different sources of nitrogen. The p h of potassium nitrate solution drifted towards neutrality after attaining considerable acidity by the 6th day. The final p h of the ammonium nitrate medium had also a tendency of drifting towards neutrality but the initial acidic trend continued for a longer time. The final p h of the ammonium nitrate solution did not reach beyond 5.2 in any case. Ammonium sulphate medium developed extreme acidity in shortest time and no upward trends were recorded during the incubation period. Addition of sodium salts of succinic or fumaric acid to ammonium sulphate solution prevented the fall of p h and normal growth was accomplished. The efficiency of the supplemented ammonium sulphate medium was better than asparagine for some of the organisms. Phyllosticta rnorifolia and P. pandanicola had better growth on supplemented ammonium sulphate medium while the influence of both the abon media was almost similar for P. bauhiniae , P. buteae and P. carica papayae . All the remaining species of Phyllosticta achieved better growth on asparagine than on ammonium sulphate fumarate or succinate media. The author is grateful to Professor R. N. T andon for his valuable suggestions

A physiological study on the toxicity of culture filtrate of Helminthosporium sativum P.K. & P.

When symptoms of the leaf-spot disease of barley caused byHelminthosporium sativum could be reproduced by dipping host plants in fungal filtrate, it was thought to trace any correlation that may exist between nitrogenous constituents of the filtrate and its wilt-inducing capacity to test plants (lupin seedlings). The fungus was grown on a modified Fries' No 3 medium with sodium nitrate or ammonium chloride or an equivalent mixture of both as nitrogen source. The nitrogen content of the culture medium and its wilt-inducing capacity were traced over 34 days. The nitrogen content, after reaching a minimum, was found to rise again; the rise being more rapid and bigger in nitrate and ammonium-nitrate media than in ammonium media. Only a partial apparent correlation could be noted between the trend in the wilt-inducing capacity of filtrates obtained at different periods of incubation, and the trend in the change in their nitrogen content. It is suggested that the toxicity of the culture filtrate may be attributed to more than one substance, one of them being a nitrogenous product (possibly of peptide nature). The observed degree of toxicity would therefore depend on the relative amounts of the nitrogenous product and other substances.