Different Concentrations Of Ammonium Chloride Research Articles

Effect of different concentrations of ammonium chloride on expression of hypoxia-inducible factor-1α in Chang liver cells

Objective: To investigate the effect of treatment with different concentrations of ammonium chloride (NH4Cl) on the mRNA and protein expression of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) in Chang liver cells. Methods: Normal Chang liver cells were cultured and treated continuously with different concentrations of NH4Cl (1.25, 2.5, and 5 mmol/L). The Chang liver cells cultured normally were used as controls. RNA and protein were extracted at the 5th, 10th, and 15th generations. Quantitative real-time PCR, immunohistochemistry, and Western blot were used to measure the expression of HIF-1α and VEGF. Results: Quantitative real-time PCR showed that compared with the control group, the NH4Cl treatment group showed significant increases in the mRNA expression of HIF-1α and VEGF across the 5th, 10th, and 15th generations (F = 90976.659/1300.218/1896.800 and 41825.754/2381.321/2591.954, all P < 0.05). The results of immunohistochemistry showed that compared with the control group, the NH4Cl treatment group showed significant increases in the protein expression of HIF-1α and VEGF across the 5th, 10th, and 15th generations (F = 376.709/1615.358/1350.120 and 904.789/5105.186/8644.498, all P < 0.05). As was shown by the results of Western blot, compared with the control group, the NH4Cl treatment group showed significant increases in the protein expression of HIF-1α and VEGF across the 5th, 10th, and 15th generations (F = 228.499/6051.974/183.219 and 5549.429/40187.665/120982.183, all P < 0.05). Conclusion: Ammonia can increase the expression of HIF-1α and its downstream gene VEGF in Chang liver cells and cause the phenomenon of pseudohypoxemia.

Improved growth performance of Gracilariopsis heteroclada via short-term nitrogen enrichment

Abstract This study examined the effect of short-term nitrogen (N) enrichment on Gracilariopsis heteroclada growth and agar quality. Planting materials were soaked in different concentrations of ammonium chloride (NH4Cl) for 6 h. Total thallus N content was highest in Gp. heteroclada enriched in 300 mg l-1 NH4Cl. Growth experiments showed that this enrichment treatment (300 mg l-1 NH4Cl for 6 h) increased the growth of Gp. heteroclada (4.22±0.09% day-1) compared with the control (3.68±0.12% day-1). Pond culture using enriched Gp. heteroclada resulted in high growth rates (6.14±0.50% day-1). No epiphyte growth was observed during either the growth experiment or the pond culture. There were no significant differences between the agar yields of the enriched (3.65±0.36%) or control (3.78±0.18%) Gp. heteroclada. Additionally, no significant differences were detected when the gel strength of the enriched (611±22 g cm-2) and control (587±11 g cm-2) Gp. heteroclada were compared. The results suggest that the short-term N enrichment method could be an alternative culture strategy to increase Gp. heteroclada production and lower farming costs.

Enhanced Bioremediation of Field Agricultural Soils Contaminated with PAHs and OCPs

Effect of different concentrations of ammonium chloride (NCL) and ammonium nitrate (NN)and surfactants such as Tween-80, HPCD and rhamnolipids on the bioremediation of PAHs and OCPs wasinvestigated. The results showed that the best optimum concentration of NCL and NN was 50 g·kg-1, and thePAHs degradation rate during 60 days of remediation was enhanced to 64.6% and 62.8% for NCL and NN,respectively, which was approximately 45, 17, 10% higher than those in the control group, soil only addedmicroorganism, soil added microorganism and tourmaline. OCP removal rates were 51.7% and 50.4 % for NCLand NN, respectively, which was 34% higher than the control group, 14% higher than the soil only addedmicroorganism, 9% higher than the soil added microorganism and tourmaline. The best dose of Tween-80,HPCD and rhamnolipids was 2, 0.5 and 0.2 g·kg-1. When they were applied, the PAHs degradation rate during60 days of remediation was enhanced to 69, 70.4 and 71.5%, respectively, which was approximately 52, 24and 17% than those in the control group, soil only added microorganism, soil added microorganism andtourmaline. Similarly, OCP removal rate was 42, 26 and 16% higher than those in the control group,microorganism -added soil alone, soil added microorganism and tourmaline. Additionally, nutrients and surfactantscan promote the generation of soil hydrogen peroxidase and invertase enzyme. Hence, the present studyprovides a promising combination remediation technology for the remediation of field soils contaminated byPAHs and OCPs.

Liquid–liquid equilibrium of 1-butanol + water + tri-n-butyl phosphate + ammonium chloride system

In this paper, the liquid–liquid equilibrium (LLE) and tie-line data of the system containing 1-butanol+water+tri-n-butyl phosphate (TBP)+ammonium chloride have been studied at 298.15, 308.15 and 318.15K under atmospheric pressure. The influence of temperature and different concentrations of ammonium chloride have been investigated. In addition, nonrandom two-liquid (NRTL) model is applied to the system, and the relevant interaction parameters are regressed with the experimental data. The quality of the correlation is measured by the rmsd (rmsd≤0.0131). The results show that the calculated values by NRTL model are in agreement with the determination of LLE data of the studied system in the investigated conditions.

Evaluation of the composition of continuously-cultivated Arthrospira ( Spirulina) platensis using ammonium chloride as nitrogen source

This work is focused on the influence of dilution rate (0.08 ≤ D ≤ 0.32 d −1) on the continuous cultivation and biomass composition of Arthrospira ( Spirulina) platensis using three different concentrations of ammonium chloride ( c No = 1.0, 5.0 and 10 mol m −3) as nitrogen source. At c No = 1.0 and 5.0 mol m −3 the biomass protein content was an increasing function of D, whereas, when using c No = 10 mol m −3, the highest protein content (72.5%) was obtained at D = 0.12 d −1. An overall evaluation of the process showed that biomass protein content increased with the rate of nitrogen supply ( D c No) up to 72.5% at D c No = 1.20 mol m −3 d −1. Biomass lipid content was an increasing function of D only when the nitrogen source was the limiting factor for the growth ( D c No ≤ 0.32 mol m −3 d −1), which occurred solely with c No = 1.0 mol m −3. Under such conditions, A. platensis reduced its nitrogen reserve in the form of proteins, while maintaining almost unvaried its lipid content. The latter was affected only when the concentration of nitrogen was extremely low ( c No = 1.0 mol m −3). The most abundant fatty acids were the palmitic (45.8 ± 5.20%) and the γ-linolenic (20.1 ± 2.00%) ones. No significant alteration in the profiles either of saturated or unsaturated fatty acids was observed with c No ≤ 5.0 mol m −3, prevailing those with 16 and 18 carbons.

Viscosities of ammonium salts in water and ethanol + water systems at different temperatures

Viscosities of different concentrations of ammonium chloride and ammonium bromide from 1 × 10 − 2 to 9 × 10 − 2 mol dm − 3 solutions in aqueous and aqueous alcoholic (10% v/v ethanol) mixtures were measured at temperatures ranging from 298 to 323 K respectively. It was observed that the viscosity of solution increased with the increase in the concentration of salts (ammonium chloride and ammonium bromide) in aqueous system and decreased in aqueous ethanol system. The viscosity data were used to evaluate ion–ion interactions and ion–solvent interactions in terms of ‘ A’ and ‘ B’ coefficients of Jones–Dole equation respectively. The positive values of B-coefficient for ammonium chloride and ammonium bromide in aqueous system indicate that ammonium chloride and ammonium bromide behave as structure maker in aqueous system while in aqueous ethanol system structure breaking behaviour was observed. With the help of viscosity data, the activation parameters such as energy of activation ( E η), free energy change of activation (Δ G⁎) and the entropy change of activation (Δ S⁎) were evaluated as a function of salt concentration, solvent composition and temperature.

Cultivation of Spirulina platensis by continuous process using ammonium chloride as nitrogen source

Abstract This work is focused on the influence of dilution rate (0.08⩽D⩽0.32 d−1) on the kinetics of continuous cultivation of Spirulina platensis at two different concentrations of ammonium chloride (N0=1.0 and 10 mM) as nitrogen source. Cell productivity increased in both series of runs up to D≅0.12–0.16 d−1, and then decreased. While at N0=1.0 mM biomass washing was certainly the cause of progressive cell concentration decrease, a combination of this phenomenon with the toxic effect of excess ammonia was responsible, at N0=10 mM and D⩾0.20 d−1, for quick stop of cell growth just beyond the achievement of maximum cell productivity (92.4 mg l−1 d−1). Similar profile was observed for protein productivity, that achieved a maximum value of 67.0 mg l−1 d−1, because of the very high protein content (72.5%) of biomass produced under these conditions. The yield of nitrogen-to-biomass was much higher at the lower N0, because of the low protein content, and reached a maximum value of 9.7 g g−1 at D=0.08–0.12 d−1. The yield of nitrogen-to-protein showed less marked difference, being most of the nitrogen present in the cell as proteins or free amino-acids.

Lipid transfer particle mediates the delivery of diacylglycerol from lipophorin to fat body in larval Manduca sexta

This work analyzed the process of lipid storage in fat body of larval Manduca sexta, focusing on the role of lipid transfer particle (LTP). Incubation of fat bodies with [(3)H]diacylglycerol-labeled lipophorin resulted in a significant accumulation of diacylglycerol (DAG) and triacylglycerol (TAG) in the tissue. Transfer of DAG to fat body and its storage as TAG was significantly inhibited (60%) by preincubating the tissue with anti-LTP antibody. Lipid transfer was restored to control values by adding LTP to fat body. Incubation of fat body with dual-labeled DAG lipophorin or its treatment with ammonium chloride showed that neither a membrane-bound lipoprotein lipase nor lipophorin endocytosis is a relevant pathway to transfer or to storage lipids into fat body, respectively. Treatment of fat body with suramin caused a 50% inhibition in [(3)H]DAG transfer from lipophorin. Treatment of [(3)H]DAG-labeled fat body with lipase significantly reduced the amount of [(3)H]DAG associated with the tissue, suggesting that the lipid is still on the external surface of the membrane. Whether this lipid represents irreversibly adsorbed lipophorin or a DAG lipase-sensitive pool is unknown. Nevertheless, these results indicate that the main pathway for DAG transfer from lipophorin to fat body is via LTP and receptor-mediated processes.

Bone, blood and faecal response to an acidogenic lick for range cattle using different concentrations of ammonium chloride.

Thirty Brahman-Angus cross heifers at breeding age on extensive grazing were used to test the effectiveness of NH4Cl as an acidogenic agent at 15,18, 21 and 26 % of a dicalcium phosphate lick (A+), compared to a lick of 5 parts dicalcium phosphate and 3 parts salt (A-). Blood and faecal phosphorus (P), faecal calcium (Ca) and faecal magnesium (Mg) were significantly (P<0.05) higher in A+ compared to A-animals at different stages of the experiment. Bone P did not increase in response to NH4Cl but bone Ca was significantly (P<0.05) higher in A+ animals offered 18% NH4Cl and significantly (P<0.05) lower at 15 and 26%. Bone Mg in A+ animals was significantly (P<0.05) higher at 15 and 18% NH4Cl and lower at 26% NH4Cl compared to A- animals. Percentage ash in bone increased linearly from 62.5 to 64.9% in A+ animals as NH4Cl was increased in the lick from 15 to 21% and then decreased to 63.3% but was significantly (P<0.05) greater than the percentage ash in A-animals when the NH4Cl was increased to 26%. Bone mineral status was only marginally improved by adding NH4Cl to the lick in this study but blood P was significantly (P<0.05) improved in A+ compared to A- animals when the lick contained 15, 21 and 26% NH4Cl. Based on bone mineral results reported here, it is recommended that, when NH4Cl is used as an acidogenic agent in licks for range cattle, the amount in the lick should not exceed 21%.

Stimulation of ureogenesis in the perfused liver of an Indian air-breathing catfish, Clarias batrachus, infused with different concentrations of ammonium chloride

The pattern of changes of activity of the urea cycle enzymes and the rate of urea-N excretion were studied in the perfused liver of an Indian air-breathing ureogenic walking catfish, Clarias batrachus. The liver was perfused with different concentrations of NH4Cl for a period of 60 min to determine the role of ammonia for stimulation of hepatic ureogenesis and the threshold level of ammonia loading needed to cause such stimulation. Both the urea-N excretion and the ammonia uptake by the perfused liver were found to be a saturable process. Ammonia accumulated significantly in the liver infused with 1.25 μmoles g liver −1 min−1 of NH4Cl, followed by a maximum accumulation of about 28.5 μmoles g wet wt−1 with the infusion of 5.08 μmoles g liver−1 min−1. The Vmax of the urea-N excretion (0.47 μmol g liver−1 min−1) was obtained with the addition of 5.08 μmoles g liver−1 min−1 of NH4Cl. Both the tissue and the specific activity of the urea cycle enzymes, except ornithine transcarbamylase and arginase, were stimulated significantly with the infusion of either 1.25 or 5.08 μmoles g liver−1 min−1 of NH4Cl. Maximum stimulation of tissue activity of carbamoyl phosphate synthetase (about 120%) was seen with the infusion of 5.08 μmol g liver−1 min−1, and for argininosuccinate synthetase (about 135%), and argininosuccinate lyase (about 50%) with the infusion of 10.81 μmol g liver−1 min−1 of NH4Cl. Higher accumulation of ammonia of about 10–15 μmol g wet wt−1 from the physiological level in the perfused liver while infusing with NH4Cl was suggested to be one of the major causes of stimulation of ureogenesis. The presence of such physiological adaptive strategy is probably necessary in this unique group of air-breathing walking catfish to survive under hyper-ammonia stress in their normal habitat or while living outside water or while burrowing inside mud.

Induction of ureogenesis in perfused liver of a freshwater teleost, Heteropneustes fossilis, infused with different concentrations of ammonium chloride

The induction pattern of urea cycle enzymes and the rate of urea-N excretion were studied with relation to ammonia load in the perfused liver of a freshwater ammoniotelic teleost, Heteropneustes fossilis, when infused with different concentrations of ammonium chloride for 60 min. Both urea-N excretion and uptake of ammonia by the perfused liver were found to be a saturable process. The V max of urea-N excretion (0.45 μmol/g liver/min) was obtained at ammonium chloride addition of 1.18 μmol/g liver/min. The maximum induction of carbamyl phosphate synthetase (ammonia dependent), ∼200%, and of ornithine transcarbamylase, ∼120%, was seen by the addition of 0.58 μmol/g liver/min, and for argininosuccinate synthetase and argininosuccinate lyase of ∼150% and 115%, respectively, by the addition of 2.8 μmol/g liver/min of ammonium chloride. However, arginase activity did not alter in any of the concentrations of ammonium chloride added. An increase of ammonia load of 3–5 μmol/g wet wt from the physiological level in the perfused liver was sufficient to initiate and to cause maximum induction of most of the urea cycle enzymes activitty. These results further confirm the capacity of transition from ammoniotelism to ureotelism in this unique freshwater air-breathing teleost to tolerate a very high ambient ammonia.

Characterization of Sorting Signals in the β-Amyloid Precursor Protein Cytoplasmic Domain

The beta-amyloid precursor protein (APP) is proteolytically processed to generate beta-amyloid protein, the principal protein component of neuropathological lesions characteristic of Alzheimer's disease. To investigate potential sorting signals in the cytoplasmic tail of APP, we transplanted APP cytoplasmic tail sequences into the cytoplasmic tail of the human transferrin receptor (TR) and showed that two sequence motifs from the APP cytoplasmic tail promote TR internalization. One sequence, GYENPTY, is related to the low density lipoprotein receptor internalization signal, FDNPVY, but also involves a critical glycine residue; the other, YTSI, conforms to the 4-residue tyrosine-based internalization signal consensus sequence. Furthermore, a chimeric molecule (APP-TR) consisting of the cytoplasmic domain of APP and the transmembrane and external domains of TR was rapidly internalized enabling the transport of iron into the cell at approximately 50% the rate of wild-type TR. Alanine scanning mutations indicated that the two sequences identified in transplantation experiments were required for internalization of the chimera. Metabolic pulse-chase experiments showed that the APP-TR chimeras were degraded in a post-Golgi membrane compartment within 2-4 h following normal glycosylation. Degradation was partially dependent upon the two internalization signals and was inhibited by ammonium chloride. A fraction of APP-TR chimeras traffic to a degradative endocytic compartment after appearing on the cell surface. Comparison of soluble APP released from cells expressing either full-length human APP or mutant APP with the sequence YENPTY deleted indicated that this sequence is required for sorting of full-length APP along similar trafficking pathways as the APP-TR chimera.

Effects of host feeding and dissolved ammonium on cell division and nitrogen status of zooxanthellae in the hydroid Myrionema amboinense

There is a relationship between host feeding, nitrogen status and mitotic activity of zooxanthellae symbiotic with the marine hydroid Myrionema amboinense. Decreases in the mitotic index of zooxanthellae in starved M. amboinense, and in internal pool sizes of glutamine and glutamate, amino acids involved in ammonium assimilation via the glutamine synthetase-glutamate synthase (GS/GOGAT) pathway, were partially restored by addition of ammonium chloride to seawater in which hydroids were incubated. Levels of glutamine were more sensitive to host starvation than levels of glutamate, resulting in a decrease in the glutamine: glutamate molar ratio to that found in zooxanthellae cultured on nitrate. Hydroids starved for 5 d and then incubated in different concentrations of ammonium chloride showed a positive correlation between ammonium concentration and mitotic index of their symbiotic zooxanthellae. Host starvation caused a decrease in perturbation of levels of glutamine and glutamate during ammonium assimilation, as well as decreases in rates of assimilation of [14C]-leucine into TCA-insoluble protein, and in photosynthetic incorporation of [14C]-bicarbonate. These observations suggest that host starvation reduces nitrogen supply to the zooxanthellae, causing nitrogen stress to the symbionts and reduction in metabolic processes associated with nitrogen assimilation and photosynthesis as well as with cell division.

Nutrient Limitation of Phytoplankton Growth in Georgia Nearshore Waters

Nutrient enrichment experiments were conducted to investigate the utilization of dissolved organic and inorganic nitrogen by marine phytoplankton in Georgia coastal waters. Natural populations of marine phytoplankton, enriched with different concentrations of ammonium chloride and other plant nutrients, were grown under controlled temperature and irradiance conditions until the populations reached “stationary phase.” Results showed that (1) phytoplankton are limited by DIN up to ca. 20μM, when another nutrient (phosphate or silicate) becomes limiting, (2) very little naturally-occurring DON is directly utilized for growth, (3) very little DON is indirectly made available for growth over time periods of days to ca. 1 week, and (4) trace metals and vitamins do not significantly limit phytoplankton growth.

Effect of Ammonia Concentration on Activity of Enzymes of Ammonia Assimilation and on Synthesis of Amino Acids by Mixed Rumen Bacteria in Continuous Culture

Rumen microorganisms from a cow fed a synthetic diet containing nonprotein nitrogen were maintained in an artificial rumen on a similar diet. Ammonia concentration in the artificial rumen was varied by infusion of different concentrations of ammonium chloride, and activities of enzymes associated with ammonia metabolism and concentration of free amino acids were assayed. Low ammonia concentration caused a ten-fold increase in the specific activity of glutamine synthetase. Activity of asparagine synthetase and aspartate aminotransferase did not respond consistently to ammonia concentration. Specific activities of reduced nicotinamide adenine dinucleotide and reduced nicotinamide adenine dinucleotide phosphate specific glutamate dehydrogenases were approximately equal when the artificial rumen was inoculated but the latter was predominant by day 4 or 5. Rumen microbial extracts possessed glutamate synthase activity which in conjunction with glutamine and asparagine synthetases may provide an efficient means of glutamate synthesis at low rumen ammonia concentrations. Aspartate and glutamate concentrations did not respond to ammonia concentrations. Alanine and glycine were metabolized readily by rumen microorganisms when the free ammonia concentration was low. When ammonia concentration was high, alanine concentration rose rapidly suggesting that alanine might serve as a storage depot for ammonia and also might provide an additional route for transport of glucose precursors (i.e., pyruvate) from the rumen.