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PubMedDate not supplied

Enhanced biological phosphorus removal from wastewater by biomass with different phosphorus contents, Part I: Experimental results and comparison with metabolic models.

Enhanced biological phosphorus removal (EBPR) in waste-water treatment involves at least two types of bacterial metabolism: a polyphosphate-accumulating metabolism (PAM) and a glycogen-accumulating metabolism (GAM). Laboratory-scale sequencing batch reactors operated in an anaerobic-aerobic cycle confirmed that low influent phosphorus/chemical oxygen demand (COD) ratio feed favored a GAM-dominated culture and high influent phosphorus/COD ratio feed favored a PAM-dominated culture, as indicated by changes in phosphorus, acetate, glycogen, and polyhydroxyalkanoate (PHA) concentrations during the anaerobic phase. Differential PAM and GAM dominance may explain variance in anaerobic phosphorus release, glycogen degradation, and PHA synthesis per acetate uptake ratios previously reported in EBPR systems and proposed metabolic models. The measurement of the ratios of anaerobic phosphorus release to acetate uptake and glycogen degradation to acetate uptake is suggested as an assay to estimate the relative dominance of PAM and GAM, respectively, in EBPR cultures.

Acetates↗
PubMed1995

[Not just for fire. The risk of production and misuse of phosphorus matches. Phosphorus necrosis, abortions and suicides during the latest half of the 1900-century].

The phosphorus match was a useful but poisonous match, used during the last half of the 1900-century. The medical consequences of the match production were far-reaching. The workers, usually women, could be affected by chronic phosphorus poisoning including necrosis in the mandible. The infected mandible had to be surgically removed if the patient should survive. In the last decades of the century the matches were used as a method for abortion and suicide. The misuse can be understood in the light of the widespread social structural changes at the time. With the right dosage, the heads of the matches could be used for abortion but many women died of acute phosphorus poisoning. An extensive debate was going on for decades in the parliament before the production of the phosphorus matches was forbidden in 1901.

Abortion, Spontaneous↗
PubMed2003

Effect of lime stabilisation of enhanced biological phosphorus removal sludges on the phosphorus availability to plants.

This study investigates the phosphorus (P) availability in lime stabilised biological phosphorus removal sludges. Lime-stabilised sludge amendments (LS), non-stabilised sludge amendments (S) and amendments with a chemical fertiliser (TSP) were compared through plant uptake of P and Olsen-extractable P for this purpose. In the first part of the study, pot experiments were performed, where a dewatered biological phosphorus removal sludge was applied to pots at increasing rates of P. A P-deficient, alkaline soil was used in the experiments and Lollium perenne was the testing plant. In the second part (incubation tests), the waste activated sludge from an Enhanced Biological Phosphorus Removal (EBPR) process was mixed with the same soil at a pre-determined P-based rate. The pot experiments showed that, the efficiency of the fertilising materials, based on the minimum P applied to reach the maximum yield, was in the following order: S approximately equal to LS > TSP. However, the P concentration in the plant tissue was in the order of TSP > S >LS for all P application rates. In the incubation tests, the EBPR sludge raised the soil P-level from the low range to the medium range. The P-availability in TSP decreased rapidly with time whereas that in S and LS remained almost constant.

Biological Availability↗
PubMed2003

Development of a high-efficiency phosphorus recovery method using a fluidized-bed crystallized phosphorus removal system.

The authors have been engaged in the research and development concerning the recovery of MAP (Magnesium Ammonium Phosphate) using a fluidized-bed crystallized phosphorus removal system. In the reactor of the fluidized-bed crystallized phosphorus removal system, seed crystals (of MAP) are fluidized previously and new MAP crystals are produced on the seed crystal surfaces. Conventionally, the reactor consisted of one reaction tank only, but this practice had the problem that as the crystallization progresses, the seed crystal is grown excessively and as a result, the effective reaction surface areas are decreased and the fluidization effect is degraded, causing the recovery ratio to be decreased. Recently, the authors have devised a two-tank type reactor by adding a sub reaction tank to the reactor (now the main reaction tank) so that the MAP particle size in the main reaction tank may be kept constant making the recovery ratio stable. They conducted a demonstration test with a pilot experimental system of the 2-tank type reactor. For raw water T-P 111 to 507 mg/L, the main reaction tank treated water T-P 14.0 to 79.5 mg/L and phosphorus recovery ratios 84 to 92% were obtained. Because the mean MAP particle size in the main reaction tank could be kept constant, the phosphorus recovery ratio could always be above 80%, realizing stable treatment.

Bioreactors↗
PubMedDate not supplied

[Effect of long-term administration of low-molecular dextran (40,000) on the blood levels of inorganic phosphorus and lipid-bound phosphorus in patients with cerebral infarction].

The effect of low-molecular dextran given on 6 days after cerebral infarction onset on the content of inorganic phosphorus and lipid-bound phosphorus was studied in 22 patients. The obtained results were compared with those in a control group. Low-molecular dextran caused a statistically significant decrease of the serum lipid-bound phosphorus level in healthy subjects and in patients, which was most pronounced on the sixth day of successive dextran administration, while it had no effect on serum inorganic phosphorus in the studied subjects.

Aged↗
PubMed1989

Effect of hypocalcemia on renal phosphorus handling in the rat: interaction with dietary phosphorus and PTH.

The effect of Na-EGTA induced hypocalcemia was investigated in chronically parathyroidectomized (PTX) rats. In dietary inorganic phosphorus (Pi) replete animals, reduction in the plasma calcium to 1.37 +/- 0.03 mM at constant filtered loads of Pi had no effect on tubular reabsorption of phosphorus (85 +/- 3 vs. 83 +/- 2 micrograms/ml, NS). In dietary Pi-deprived rats, where an elevation of plasma calcium is a known accompaniment, similar reduction in plasma calcium concentration also failed to alter (89 +/- 2 vs. 90 +/- 2 micrograms/ml, NS) phosphorus reabsorption. Resistance to parathyroid hormone (PTH) in dietary Pi deprivation was confirmed. Super imposition of PTH on EGTA induced hypocalcemia during dietary Pi deprivation, however, resulted in a significant reduction in tubular Pi reabsorption (81 +/- 2 vs. 67 +/- 3 micrograms/ml, p less than 0.05) with full restoration of its phosphaturic action. These changes were unaccompanied by differences in urinary adenosine 3',5'-cyclic phosphate (cAMP). In conclusion, hypocalcemia per se does not alter the renal handling of phosphorus at constant plasma Pi concentrations. The elevation in the plasma calcium associated with dietary Pi deprivation does not contribute importantly to the hypophosphaturia of dietary Pi deprivation. Hypocalcemia, however, abolishes the resistance to PTH observed in Pi deprivation.

Animals↗
PubMed1980

The use of faecal analyses to estimate the phosphorus intake by grazing sheep. II. The repeatibility of the technique and the influence of varying the phosphorus intake.

Fifty sheep received a pelleted ration containing between 0,31 and 0,38% phosphorus. Pooled faecal samples, composed of 3 faecal pellets from 30 randomly selected sheep, were taken on 15 occasions during 23 days. The faecal phosphorus levels of the 15 pooled samples were remarkably constant with a mean of 0,94% and a coefficient of variation of 6,38%. However, when the animals the faecal phosphorus levels above and below the limits set in the repeatabilty trial. There was also a rise in faecal phosphorus when the total food intake was halved. The faecal samples were also analysed for calcium and magnesium.

Animals↗
PubMed1993

[Therapeutic effect of calcium preparation in phosphorus poisoning following phosphorus burns].

All of 20 patients with phosphorus burn, admitted from 1987 to 1991, have been cured by intravenous drip of calcium gluconate combined with other therapies. The wounds were washed with tap water, followed by eschar formation in 12 days. The clinical data showed that phosphorus poisoning did not occur if calcium was given very early postburn. Calcium also could abolish or ameliorate clinical manifestations of existing phosphorus poisoning, accelerate the elimination of phosphorus and recovery of damaged organs.

Adult↗
PubMed2004

Electron spin resonance study of phosphorus-nitroxides from 1,3-additions of silicon-phosphorus reagents to nitrones.

This article explores a new, convenient route to beta-phosphorus nitroxides. Specifically, the reaction sequence involves the novel 1,3-addition of trimethylsilyl phosphites (e.g. diethyl) or trimethylsilyl phosphines (e.g. diphenyl) to aldo-nitrones [e.g. alpha-phenyl-N-tert-butylnitrone (PBN) or 5,5-dimethyl-l-pyrroline-N-oxide (DMPO)] or keto-nitrones [e.g. 2-ethyl-5,5-dimethyl-1 pyrroline-N-oxide (2-Et-DMPO) or 2-phenyl-5,5-dimethyl-l-pyrroline-N-oxide (2-Ph-DMPO)] to form alpha-phosphityl- or alpha-phosphinyl-O-silylhydroxylamines. Acidic hydrolysis provides the corresponding hydroxylamines that are easily oxidized to the title beta-phosphorus-nitroxides. ESR spectroscopic analysis revealed some very large beta-phosphorus hyperfine splittings (i.e. in excess of 5 mT). For this reason and their remarkable stability (persistence) some of these nitroxides show promise as integral components in new, improved weak-field dynamic nuclear polarization (DNP) magnetometers.

Cyclic N-Oxides↗
PubMed1992

Phosphorus-31 NMR studies of stabilized phosphorus ylids in the solid state.

Phosphorus-31 powder NMR spectra and high-resolution MAS spectra have been obtained for a number of stabilized phosphorus ylids under conditions of high-power proton decoupling and cross-polarization. The 31P CP/MAS spectra are compared to those obtained from isotropic solutions. The variation of chemical shift anisotropy and of the principal components of the 31P chemical shift tensor determined from 31P powder NMR line shapes are discussed in terms of the relative importance of accepted valence bond resonance structures. The results indicate that the invariance of the isotropic chemical shift, delta iso, observed in previous 31P NMR investigations of phosphorus ylids in solution is due to fortuitous cancellation of opposing changes in the principal components, delta 11 and delta 33, of the 31P chemical shift tensor. The 31P dipolar NMR powder spectrum of a typical stabilized ylid, (C6H5)3(31)P-13CHC(O)OCH2CH3, is analyzed in order to obtain the orientation of the 31P chemical shift tensor with respect to the 31P-13C alpha dipolar vector.

Magnetic Resonance Spectroscopy↗
PubMed2002

Polyhydroxyalkanoates form potentially a key aspect of aerobic phosphorus uptake in enhanced biological phosphorus removal.

Eighteen anaerobic/aerobic batch experiments were conducted with a variety of volatile fatty acids (VFAs) on a sequencing batch reactor (SBR) population displaying enhanced biological phosphorus removal (EBPR). A statistically significant (P << 0.01 for all variables) correlation between aerobic phosphorus uptake and polyhydroxyalkanoates (PHAs) quantity and form was observed. The results suggest that poly-3-hydroxy-butyrate (3HB) results in significantly higher aerobic phosphorus (P) uptake per unit mmoles as carbon (mmoles-C) than poly-3-hydroxy-valerate (3HV). The results showed that acetic and isovaleric acids resulted in higher P removals (relative to propionic and valeric acids) during EBPR batch experiments not because of higher PHAs quantity, but largely because the predominant type was 3HB rather than 3HV. In contrast propionic and valeric acids resulted in 3HV, and showed much lower aerobic P uptake per unit PHAs.

Bacteria, Aerobic↗
PubMedDate not supplied

Effects of Aspergillus fumigatus phytase on phosphorus digestibility, phosphorus excretion, bone strength and performance in pigs.

Phytic-phosphorus has a very low bioavailability for monogastric animals and the non-utilized mineral contributes to the phosphorus (P) pollution problems. Phytases may ameliorate phytic-P antinutritive properties. However, phytases are very sensitive to the pelleting temperature commonly used for compound feed production and thus the challenge to produce a more thermostable phytase is very important. Pure Aspergillus fumigatus phytase (AFP) has the ability to refold into a native-like fully active structure after heat denaturation (20 min at 90 degrees C). The aim of the present work was to evaluate in vitro (in feed) and in vivo in young and in growing-finishing pigs the effects of AFP included in the feed at a level of 500 U/kg. Feed supplementation with AFP resulted in an in vitro phosphorus release of about three times higher than that obtained from the basal diets, irrespective of the pH value used for the determination (5.5 or 7). When the supplemented feed was steam pelleted at about 84 degrees C, the free P obtained after incubation at pH 5.5 represented 53% on an average of that obtained from the corresponding mash diets. The phytic-P-rich diets systematically induced hypophosphataemia, hypercalcaemia and hyperphosphatasaemia. The normal blood levels of P, Ca and alkaline phosphatase were restored by AFP. P apparent digestibility was significantly higher for the AFP diet (52.8 versus 30.8%). The improvement in Ca digestibility was not statistically significant. In all three in vivo experiments, AFP significantly decreased the P concentration in faeces (between 13 and 33%) as well as increased the growth rate and decreased the feed conversion ratio. Bone strength was significantly higher in the growing-fattening pigs fed on the AFP diet.

6-Phytase↗
PubMed1985

Phosphorus-31 nuclear magnetic resonance studies on intact erythrocytes. Determination of intracellular pH and time course changes in phosphorus metabolites.

A method to determine the intracellular pH of intact erythrocytes using phosphorus-31 nuclear magnetic resonance spectroscopy is described. Changes in phosphorus metabolites due to the alkalization of intracellular pH were also examined. The normal erythrocytes gave signals of phosphate groups corresponding to 2,3-bisphosphoglycerate, inorganic phosphate, ATP, and NAD. Among them, the separation between alpha and gamma peaks of ATP was shown to be a good indicator of the intracellular pH free from the perturbation caused by hemoglobin. This method enabled us to determine the intracellular pH of the erythrocytes without any pretreatment. The separation between alpha and gamma peaks of ATP was also dependent on the degree of complexation with Mg2+, and was consistent with approximately 80% of total ATP complexing with Mg2+ in the samples investigated here. The pKa value of ATP in the erythrocytes was estimated to be 6.1 at 23 degrees C, which is lower than the value of 6.5 obtained for the Mg2+-free ATP solution. In the alkalized erythrocytes, fructose 1,6-bisphosphate and dihydroxyacetone phosphate were observed in addition to the metabolites found in the normal erythrocytes. Time course changes in these phosphorus metabolites were followed along with the intracellular pH monitored from ATP peaks.

Adenosine Triphosphate↗
PubMed2004

Low phosphorus tolerance mechanisms: phosphorus recycling and photosynthate partitioning in the tropical forage grass, Brachiaria hybrid cultivar Mulato compared with rice.

The Brachiaria hybrid cv. Mulato is well adapted to low-fertility acid soils deficient in phosphorus (P). To study the grassy forage's mechanisms for tolerating low P supply, we compared it with rice (Oryza sativa L. cv. Kitaake). We tested by using nutrient solution cultures, and quantified the effects of P deficiency on the enzymatic activities of phosphohydrolases and on carbon metabolism in P-deficient leaves. While P deficiency markedly induced activity of phosphohydrolases in both crops, the ratio of inorganic phosphorus to total P in leaves was greater in Brachiaria hybrid. Phosphorus deficiency in leaves also markedly influenced the partitioning of carbon in both crops. In the Brachiaria hybrid, compared with rice, the smaller proportion of (14)C partitioned into sugars and the larger proportion into amino acids and organic acids in leaves coincided with decreased levels of sucrose and starch. Hence, in P-deficient leaves of the Brachiaria hybrid, triose-P was metabolized into amino acids or organic acids. Results thus indicate that the Brachiaria hybrid, compared with rice, tolerates low P supply to leaves by enhancing sugar catabolism and by inducing the activity of several phosphohydrolases. This apparently causes rapid P turnover and enables the Brachiaria hybrid to use P more efficiently.

Brachiaria↗
PubMed2004

The role of misorientation and phosphorus content on grain growth and intergranular fracture in iron-carbon-phosphorus alloys.

The relationship between the crystallography of intergranular fracture and phosphorus segregation has been investigated in a Fe-0.06wt%P-0.002wt%C alloy aged for 1 h at temperatures between 600 degrees C and 1000 degrees C. Two novel techniques were devised for the investigation: first, electron back-scatter diffraction (EBSD) across the reconstructed fracture surface and, second, a combination of Auger electron spectroscopy, stereophotogrammetry and microscopy to measure phosphorus and carbon on fracture facets combined with EBSD measurements direct from the fracture surface. In total, 700 misorientations were measured from across the reconstructed fracture surface and in 'control' areas away from the fracture. It was found that Sigma 3s were in general more resistant to brittle fracture than were random boundaries, and it was suggested that alloys of this type could be grain boundary engineered to improve fracture resistance by a short anneal in the austenite region to increase the final proportion of Sigma 3s. Sixteen fracture facets yielded combined Auger/EBSD data. The combined Auger/EBSD methodology to acquire joint crystallographic and segregation information from facets was shown to be feasible, although laborious. There were significantly more [110] planes than any other type in the sample population of facets from which combined segregation/crystallography data had been collected. The data suggested that there was on average lower phosphorus segregation on fracture facets that were near [110] than on other intergranular fracture facets.

Alloys↗
PubMed1983

In vivo one-dimensional imaging of phosphorus metabolites by phosphorus-31 nuclear magnetic resonance.

A phosphorus-31 nuclear magnetic resonance imaging technique has been used to obtain information on phosphorus metabolites from different spatial regions of tissues in vivo. The technique for selection of planes through the tissue is based on phase-encoding of spin echoes and was used to obtain one-dimensional discrimination of phosphorus-31 spectra from different parts of the tissue simultaneously. Specimens were resolved into 16 distinct slices and a signal-to-noise ratio of about 20 to 1 was obtained in 1/2 hour. Results are presented for phantoms, rat legs, and gerbil heads.

Adenosine Triphosphate↗
PubMed2003

Management of secondary hyperparathyroidism: the importance and the challenge of controlling parathyroid hormone levels without elevating calcium, phosphorus, and calcium-phosphorus product.

Secondary hyperparathyroidism (HPT) is a common complication of chronic kidney disease (CKD) that can lead to clinically significant bone disease. Additional consequences of secondary HPT, such as soft-tissue and vascular calcification, cardiovascular disease, and calcific uremic arteriolopathy, may contribute to the increased risk of cardiovascular morbidity and mortality among CKD patients. Secondary HPT arises from disturbances in calcium, phosphorus, vitamin D and parathyroid hormone metabolism, which develop early in the course of CKD and become more prominent as kidney function declines. The standard therapies currently recommended to correct mineral metabolism and bone disease in these patients include calcium supplementation, dietary phosphorus restriction, phosphate-binding agents, and treatment with vitamin D sterols. However, such medications often have significant effects on the serum levels of calcium and phosphorus, which result in exacerbation of the disease and significant extraskeletal morbidity and mortality. Thus, there is a need to identify more effective treatment approaches. This review discusses the pathophysiology of secondary HPT, the challenges faced in the management of this disorder, and the impact of current treatment options on patients' risks of morbidity and mortality. In addition, the development of new, more physiologically relevant therapies, which may lead to successful management of secondary HPT, is reviewed.

Calcitriol↗
PubMed2005

An alum-based water treatment residual can reduce extractable phosphorus concentrations in three phosphorus-enriched coastal plain soils.

The accumulation of excess soil phosphorus (P) in watersheds under intensive animal production has been linked to increases in dissolved P concentrations in rivers and streams draining these watersheds. Reductions in water dissolved P concentrations through very strong P sorption reactions may be obtainable after land application of alum-based drinking water treatment residuals (WTRs). Our objectives were to (i) evaluate the ability of an alum-based WTR to reduce Mehlich-3 phosphorus (M3P) and water-soluble phosphorus (WSP) concentrations in three P-enriched Coastal Plain soils, (ii) estimate WTR application rates necessary to lower soil M3P levels to a target 150 mg kg(-1) soil M3P concentration threshold level, and (iii) determine the effects on soil pH and electrical conductivity (EC). Three soils containing elevated M3P (145-371 mg kg(-1)) and WSP (12.3-23.5 mg kg(-1)) concentrations were laboratory incubated with between 0 and 6% WTR (w w(-1)) for 84 d. Incorporation of WTR into the three soils caused a near linear and significant reduction in soil M3P and WSP concentrations. In two soils, 6% WTR application caused a soil M3P concentration decrease to below the soil P threshold level. An additional incubation on the third soil using higher WTR to soil treatments (10-15%) was required to reduce the mean soil M3P concentration to 178 mg kg(-1). After incubation, most treatments had less than a half pH unit decline and a slight increase in soil EC values suggesting a minimal impact on soil quality properties. The results showed that WTR incorporation into soils with high P concentrations caused larger relative reductions in extractable WSP than M3P concentrations. The larger relative reductions in the extractable WSP fraction suggest that WTR can be more effective at reducing potential runoff P losses than usage as an amendment to lower M3P concentrations.

Agriculture↗