Ammonium Phosphate Concentrations Research Articles

Influence of different concentrations of ammonium phosphate on nitrogen assimilation of red seaweed Kappaphycus striatus

Eucheumatoid farming is among the most popular source of livelihood for coastal dwellers, especially in the southern Philippines. Kappaphycus and Eucheuma are the two major cultured eucheumatoid species. However, seaweed farmers have been experiencing low seaweed production for the past years. The slow growth of Kappaphycus spp. in the farm is linked to extensive farming, causing nutrient depletion in the seawater. Hence, seaweed farmers in the province of Tawi-Tawi, southern Philippines, enrich their seaweeds, Kappaphycus striatus, with a wide range of inorganic nutrient solution concentrations with an average of nearly 9 g L⁻¹. To provide standard concentration (g L⁻¹) of inorganic nutrient solution for soaking before farming the seaweed, this study investigated nitrogen assimilation using the Kjeldahl method. Treatments were the concentrations of commonly used inorganic fertilizer [ammonium phosphate, (NH4)3PO4] dissolved in filtered seawater namely; T1 = 0 g L⁻¹ as control, T2 = 3 g L⁻¹, T3 = 6 g L⁻¹, and T4 = 9 g L⁻¹. Results showed that the total nitrogen (%) of T4 (0.68±0.01) and T3 (0.59±0.07) were significantly higher (p<0.05) than T2 (0.48±0.02) and T1 (0.46±0.02). This suggests that using inorganic nutrients as enrichment to K. striatus at a concentration of 6 or 9 g L⁻¹ is effective for obtaining high nitrogen assimilation. Therefore, considering the cost-effective inorganic nutrient enrichment practice, this study recommends using 6 g L⁻¹ of inorganic nutrient concentration to help seaweed farmers boost production by improving the growth performance of K. striatus, especially when planted in nutrient-depleted farms.

Effects of different concentrations of ammonium phosphate on the yield and quality of carrageenan, Kappaphycus striatus (Schmitz) Doty ex Silva

This study determined the effect of different concentrations of ammonium phosphate on the yield and quality (gel strength, viscosity, syneresis, gelling, and melting temperature) of carrageenan. The study was conducted at the Seaweeds Post-Harvest Laboratory, College of Fisheries, Mindanao State University for 33 days. The experiment involved four treatments and three replications. The four treatments were the different concentrations of ammonium phosphate (g/L) namely; Treatment 1 (T1) - 0g/L, Treatment 2 (T2) – 3 g/L, Treatment 3 (T3) – 6 g/L, Treatment 4 (T4) – 9 g/L. The results showed that the application of ammonium phosphate significantly reduced the yield and viscosity of the carrageenan by 4.81% and 1.83cPs respectively. Gel strength was enhanced by 1.53g in T2 (3/L). Control showed the best syneresis compared to the other treatment. The syneresis was significantly decreased by 5.43% with the application of ammonium phosphate. The fertilizer seemed not to have any effect on the gelling and melting temperature of the carrageenan. Ammonium phosphate is therefore not recommended for growing Kappaphycus striatus for carrageenan.

New insights on protective treatments for marble by FIB-SEM

In this study, we investigated by FIB-SEM the microstructure of protective coatings formed by two inorganic treatments (namely, ammonium oxalate and ammonium phosphate solutions), with the aim of identifying the factors limiting the protective efficacy of the coatings and outlining possible improvement strategies. In the case of the oxalate treatment, the resulting layer of whewellite was found to contain vertical channels, which can allow water to reach the marble surface and trigger dissolution. Possible prevention of the formation of these channels by addition of a calcium source to the oxalate solution was attempted, but even micromolar additions led to rapid precipitation in the solution. In the case of the phosphate treatment, the resulting hydroxyapatite and octacalcium phosphate coating was found to be cracked and porous. To prevent cracks and pores, diminishing the ammonium phosphate concentration and adding ethanol to the solution were found to be effective strategies, as cracks were prevented and pores were reduced almost to zero. The resulting protective efficacy of the coating was found to be significantly improved, although still not perfect.

Bone protein extraction without demineralization using principles from hydroxyapatite chromatography

Historically, extraction of bone proteins has relied on the use of demineralization to better retrieve proteins from the extracellular matrix; however, demineralization can be a slow process that restricts subsequent analysis of the samples. Here, we developed a novel protein extraction method that does not use demineralization but instead uses a methodology from hydroxyapatite chromatography where high concentrations of ammonium phosphate and ammonium bicarbonate are used to extract bone proteins. We report that this method has a higher yield than those with previously published small-scale extant bone extractions, with and without demineralization. Furthermore, after digestion with trypsin and subsequent high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS) analysis, we were able to detect several extracellular matrix and vascular proteins in addition to collagen I and osteocalcin. Our new method has the potential to isolate proteins within a short period (4h) and provide information about bone proteins that may be lost during demineralization or with the use of denaturing agents.

Production of the polysaccharide curdlan by anAgrobacteriumstrain grown on a plant biomass hydrolysate

Production of the commercially available polysaccharide curdlan by Agrobacterium sp. strain ECP-1, isolated as a mutant strain from ATCC 31749, on a medium containing a hydrolysate of the plant prairie cordgrass with selected ammonium phosphate concentrations was investigated for a period of 144 h. Although several ammonium phosphate concentrations supported curdlan production by the strain, the optimal concentration after 120 or 144 h was 3.3 mmol·L⁻¹. Only ammonium phosphate concentrations of 1.1 or 8.7 mmol·L⁻¹ failed to support curdlan production by the strain after 120 or 144 h. Biomass production by strain ECP-1 on the hydrolysate-containing medium after 120 or 144 h was comparable, independent of the ammonium phosphate concentration present. The curdlan yield from the cordgrass hydrolysate indicated that the grass was an effective plant biomass substrate for polysaccharide production.

Optimization of ethanol, citric acid, and α-amylase production from date wastes by strains of Saccharomyces cerevisiae, Aspergillus niger, and Candida guilliermondii

The present study deals with submerged ethanol, citric acid, and α-amylase fermentation by Saccharomyces cerevisiae SDB, Aspergillus niger ANSS-B5, and Candida guilliermondii CGL-A10, using date wastes as the basal fermentation medium. The physical and chemical parameters influencing the production of these metabolites were optimized. As for the ethanol production, the optimum yield obtained was 136.00±0.66g/l under optimum conditions of an incubation period of 72h, inoculum content of 4% (w/v), sugars concentration of 180.0g/l, and ammonium phosphate concentration of 1.0g/l. Concerning citric acid production, the cumulative effect of temperature (30°C), sugars concentration of 150.0g/l, methanol concentration of 3.0%, initial pH of 3.5, ammonium nitrate concentration of 2.5g/l, and potassium phosphate concentration of 2.5g/l during the fermentation process of date wastes syrup did increase the citric acid production to 98.42±1.41g/l. For the production of α-amylase, the obtained result shows that the presence of starch strongly induces the production of α-amylase with a maximum at 5.0g/l. Among the various nitrogen sources tested, urea at 5.0g/l gave the maximum biomass and α-amylase estimated at 5.76±0.56g/l and 2,304.19±31.08μmol/l/min, respectively after 72h incubation at 30°C, with an initial pH of 6.0 and potassium phosphate concentration of 6.0g/l.

Effects of some mineral compounds on the salivary α-amylase activity of the sunn pest, Eurygaster integriceps (Put.) (Heteroptera: Scutelleridae)

In this study, the effects of two concentrations (1 and 3 mM) of ammonium nitrate (AN), ammonium phosphate (AP), ammonium sulfate (AS), copper chloride (CC), magnesium chloride (MC), magnesium nitrate (MN), magnesium sulfate (MS), potassium nitrate (PN), sodium nitrate (SN) and sodium phosphate (SP) on salivary α-amylase activity of adults of the sunn pest, Eurygaster integriceps (Put.) (Heteroptera: Scutelleridae) were evaluated 30 minutes after incubation. Distilled water was considered as the control. The results showed that the effects of the mineral compounds on adults’ α-amylase activity were significant (P<0.01). CC, AS, SN, MC, MN (all at concentrations of 1 and 3 mM) and AP (1 mM) significantly inhibited the α-amylase activity in E. integriceps. AN and MS (1 mM); and SP and MS (3 mM) reduced the enzyme activity; however, the reduction amounts were not significant. 3 mM concentrations of PN, AN and AP activated the enzyme very slightly (0.6, 1.5 and 3.1 percent, respectively). PN and SP (1 mM) activated the salivary α-amylase significantly (19.1 and 10.5 percent, respectively). Enzyme was active at pH values ranging from 4.5 to 10, but its maximum activity was observed at pH=5.

Optimization of Xylanase Production by Sporotrichum thermophile Using Corn Cobs and Response Surface Methodology

AbstractA 32 central composite experimental design was performed with the aim of optimizing the production of xylanase by Sporotrichum thermophile grown on corn cobs in submerged cultures. Various carbon and nitrogen sources were consecutively optimized, and corn cobs and ammonium phosphate concentrations were selected as substrates to test the effect of two variables, i.e., both substrate concentrations, on xylanase production. A second‐order quadratic model and a response surface method showed that the optimum conditions for xylanase production were 2.7 % [w/v] corn cobs and 0.7 % [w/v] ammonium phosphate. These optimum conditions were transferred to 7 L bioreactors, where activities as high as 56 U/mL were obtained.

Nitrogen repression of fumonisin B1 biosynthesis inGibberella fujikuroi

Fumonisins are a group of structurally related mycotoxins produced by Gibberella fujikuroi. The fungus produced fumonisin B1 (FB1) as early as 18 hour in a defined medium containing 1.25 mM or 2.5 mM ammonium phosphate, whereas fumonisin B1 production was repressed for 75 hour and 125 hour when mycelia were resuspended in media containing ammonium phosphate at 10 mM or 20 mM, respectively. Although total fumonisin B1 production was greater in resuspension cultures grown in higher concentrations of ammonium phosphate, the accumulation was independent of the inoculum size and carbon/nitrogen ratio. The addition of ammonium phosphate to cracked corn cultures also repressed fumonisin B1 production by 97%, and persisted for at least three weeks. Thus, biosynthesis of fumonisin B1 is regulated by a mechanism involving nitrogen metabolite repression, suggesting that control strategies that target the regulatory elements of nitrogen metabolism may be effective at reducing the risk of fumonisin contamination in food.

Nitrogen repression of fumonisin B1 biosynthesis in Gibberella fujikuroi

Fumonisins are a group of structurally related mycotoxins produced by Gibberella fujikuroi. The fungus produced fumonisin B1 (FB1) as early as 18 hour in a defined medium containing 1.25 mM or 2.5 mM ammonium phosphate, whereas fumonisin B1 production was repressed for 75 hour and 125 hour when mycelia were resuspended in media containing ammonium phosphate at 10 mM or 20 mM, respectively. Although total fumonisin B1 production was greater in resuspension cultures grown in higher concentrations of ammonium phosphate, the accumulation was independent of the inoculum size and carbon/nitrogen ratio. The addition of ammonium phosphate to cracked corn cultures also repressed fumonisin B1 production by 97%, and persisted for at least three weeks. Thus, biosynthesis of fumonisin B1 is regulated by a mechanism involving nitrogen metabolite repression, suggesting that control strategies that target the regulatory elements of nitrogen metabolism may be effective at reducing the risk of fumonisin contamination in food.

Physiology of exolaccase production by Thelephora terrestris

Thelephora terrestris, an ectomycorrhizal hymenomycete, produces extracellular laccase when grown in minimal liquid medium. The enzyme was characterized as a protein of 66 kDa. The optimal pH varied depending on the substrate utilized, being 5.0 for syringaldazine, 4.8 for guaiacol and 3.4 for ABTS. The K m was 2.52±0.4 μM for syringaldazine, 16±1.9 μM for ABTS and 120.6±4.9 μM for guaiacol. The secretion of laccase was biomass-dependent and independent of the glucose concentration in the medium. The addition of inducers did not increase laccase production which was dependent upon the ammonium phosphate concentration.

Physiology of exolaccase production byThelephora terrestris

Thelephora terrestris, an ectomycorrhizal hymenomycete, produces extracellular laccase when grown in minimal liquid medium. The enzyme was characterized as a protein of 66 kDa. The optimal pH varied depending on the substrate utilized, being 5.0 for syringaldazine, 4.8 for guaiacol and 3.4 for ABTS. The Km was 2.52±0.4 μM for syringaldazine, 16±1.9 μM for ABTS and 120.6±4.9 μM for guaiacol. The secretion of laccase was biomass-dependent and independent of the glucose concentration in the medium. The addition of inducers did not increase laccase production which was dependent upon the ammonium phosphate concentration.

Lipid composition of Euglena gracilis in relation to carbon-nitrogen balance

The lipid class and fatty acid compositions of Euglena gracilis were analysed after growth under various conditions of autotrophy or photoheterotrophy, in order to identify the contribution of lactate (a carbon source) and ammonium phosphate (a nitrogen source) to the metabolism of these compounds. When ammonium and lactate were both present in the medium, in concentrations that allowed growth, the lipid composition of algae appeared to be independent of the ammonium concentration. The effects of increasing ammonium phosphate concentration on lipid metabolism were observed only when lactate was depleted. With increasing nitrogen concentration in the medium, an increase in the content of galactolipids rich in polyunsaturated C 16 and C 18 fatty acids (FA) was noted, as well as an increase in the monogalactosyldiacylglycerol: digalactosyldiacylglycerol ratio; these changes could be related to an increase in the number of the stacked lamellae present in chloroplasts. Nitrogen concentration had no influence on the C 12 and C 14 FA but induced a loss of C 22 FA. In the absence of ammonium phosphate in the culture medium, increasing lactate concentrations were accompanied by a decrease in all plastid lipids, whereas the content of storage lipids (enriched in 14 : 0 and 16 : 0) increased. Partial inhibition of the polydesaturation of C 18 FA was observed and was accompanied by an accumulation of 18 : 1.

Studies on the Biosynthesis of L-Alanine Dehydrogenase by Cuinnghamella elegans

Summary Cell-free extracts of Cunninghamella elegans grown on L-alanine as sole source of nitrogen contained L-alanine dehydrogenase that catalyzes the oxidative deamination of L-alanine to equimolar amounts of pyruvate and ammonia. The enzyme was produced during the logarithmic phase of growth, and maximum yield was obtained after 5 d of incubation. The optimum pH range for growth and enzyme synthesis was 5.0–7.0. L- Alanine dehydrogenase of C. elegans was induced by L-alanine, DL-alanine, L-aspartic acid, L-asparagine and ammonium phosphate, but L-alanine was the best inducer. Maximum growth and enzyme formation were obtained when L-alanine concentration of the medium was 2.1 g/l. Increasing ammonium phosphate concentration in the culture medium stimulated L-alanine dehydrogenase synthesis. The effect of different carbon sources and metal salts on growth and enzyme production was studied.

Reversed-phase liquid chromatography of 5-fluoro-uracil nucleosides and nucleotides in the presence of quaternary ammonium ions

Reversed-phase liquid chromatography is used for the separation of 5-fluoro-uracil, its deoxyribo- and ribonucleosides and nucleotides. The bases and nucleosides are easily separated from their naturally occurring analogues on an octadecyl silica column eluted with 2·10 −2 M KH 2PO 4 (pH 5.0) containing 5% (v/v) of methanol. This system can be applied to the measurement of 5-fluoro-2′-deoxyuridine serum levels down to 0.1 μg/ml. Addition of small amounts (10 −3 M) of tetrabutylammonium phosphate to the eluent results in a large retention increase for the nucleotides, while the capacity ratios of the bases and nucleosides remain unchanged. The influence of the tetrabutylammonium phosphate and ammonium phosphate concentrations and pH of the eluent on the various k′ values was investigated. Evidence is presented indicating that the quaternary ammonium compound is adsorbed onto the octadecyl silica surface; nucleotides are probably retained as adsorbed tetrabutylammonium ion-pairs.

The Relation of the Composition of the Culture Medium to the Formation of Endospores by Aerobic Bacilli

1. Spore formation in eight typical members of the genusBacillushas been studied.2. Three of these strains, including one species ofB. anthracis, have been found to be practically asporogenous under the experimental conditions. In general the following statements hold good for the sporogenous races studied.3. Spore formation is almost, or entirely, inhibited by cultivation on media rich in amino acids, such as tryptic digests of casein or meat. Similar inhibition results following cultivation on a medium containing reasonably high concentrations of a mixture of amino acids and asparagine.4. When such media are suitably diluted with standard inorganic salt solutions the percentage of spores formed is greatly increased, and frequently at least 99 per cent. of spores are formed if the dilution is sufficiently high.5. When simple nitrogenous compounds such as amino acids are added to a dilute casein digest medium in which sporulation is almost complete, a definite decrease in the percentage of spores present is observed. Asparagine, which is probably readily assimilated, apparently completely hinders spore formation in most cases. Other amino acids do not exert so pronounced an effect, and ammonium phosphate does not appreciably inhibit the formation of spores.6. The fact that the addition of glycine suppresses growth markedly when it is added to a dilute casein digest medium, but does not appreciably hinder sporulation, suggests that the formation of spores is not due to any toxic effect of added compounds, or compounds already present in the medium.7. Sporulation is almost complete in a “synthetic” medium in which low concentrations of ammonium phosphate and sucrose represent the sources of nitrogen and carbon, respectively. However, frequent transfers in such a medium may inhibit spore formation partially or entirely in certain instances. This effect probably depends upon the enhanced ability of the culture in question to utilise sucrose as a source of carbon when cultivated constantly in its presence.8. It is concluded, from the above data, that endospore formation in aerobic bacilli bears an inverse relationship to the amount of available nutrient material present in the culture medium.I am indebted to Prof. Sir F. G. Hopkins and Miss M. Stephenson for their constant encouragement during the progress of this work. My thanks are due to Mr Pirie of this Department who kindly furnished me with several of the amino acids employed, and to Dr Miles of the Department of Pathology for his kindness in supplying me with certain of the cultures.