Phosphate mobility

M. Kamh, W. J. Horst, F. Amer, and H. Mostafa, Exudation of organic anions by white lupin Lupinus albus L.) and their role in phosphate mobilization from... 

In sub-FC, a detailed study of the influence of mobile phase additives on the chiral resolution of isoxazoline-based Ilb/IIIb receptor antagonists was carried out by Blackwell [145] on Chiralcel OD-H CSPs. The different mobile phase additives used were acetic acid, trifluoroacetic acid, formic acid, water, triethylamine, triethanolamine, n-hexylamine, trimethyl phosphate, and tri-w-butyl phosphate. In general, n-hexylamine and tri-/ -butyl phosphate mobile phase additives resulted in better resolution. The chiral separation of four 1,3-dioxolane derivatives on an amylose-based column has been described [151]. The effects of mobile phase composition, temperature, and pressure have been investigated. The nature of the modifier is the main parameter it has the highest impact on chiral resolution and is more important than the polarity of the mobile phase. Therefore, the organic modifier that gave the best enantiomeric separation was different for each compound. 

Roden, E.E., and Edmonds, J.W. (1997) Phosphate mobilization in iron-rich anaerobic sediments microbial Fe(III) oxide reduction versus iron-sulfide formation. Arch. Hydrobiol. 139, 347-378. 

Two new vitamin D analogues, maxacalcitol [29] and hexafluorocalcitriol [30] (Fig. 2.5) were designed to separate the antiproliferative effects of the natural hormone from its role in calcium and phosphate mobilization. There had not been... 

Figure 4.5 HPLC analysis of enzymatic assay with ATP in free and metal-bound forms. Separations were carried out on a reversed-phase C 8 column with a potassium phosphate mobile phase containing 10% methanol. The flow rate was 2 mL/min. Assay mixture of 100 /xL contained 8 mAf Tris-HCl (pH 7.5), 2 mM ATP, and 2 mM MgCl2 and enzyme preparation containing ATP pyrophosphohydrolase (10 /xg of protein). Chromatograms of 20 /xL samples illustrate incubation of (A) zero time and (B) 2 hours. (From Jahngen and Rossomando, 1983).

Figure 4-58 shows an overlay of chromatograms for labetalol with different analyte loads from 1 to 50 pg using a 10 mM dihydrogen phosphate mobile... 

Three ion-exchange chromatographic separations examined (1) Dionex ASM column using a phosphate mobile phase, (2) an AS 16 column with hydroxide eluent and (3) an AS7 column with nitric acid mobile phase... 

MMA and DMA separated on anion-exchange column (Hamilton PRPX-100) with phosphate mobile phase lOmmol L. pH 6 on-line ICP-MS... 

It is clear that the biochemical mechanisms whereby the vitamin D hydroxylases of the kidney are regulated have not been solved. It is nevertheless also clear that the need for calcium or the need for phosphorus will stimulate the production of 1, 25-(0H)2D3, a hormone which functions both in calcium mobilization and in phosphate mobilization. Additionally, calcium regulation is mediated for the most part by the parathyroid hormone. Finally, l,25-(OH)2D3 itself plays an important role in this regulation by inducing the 244iydroxylase and suppressing the 1-hydroxylase. 

It may seem disturbing that 1,25-(OH)2D3 can be considered a hormone with two signals (low calcium and low phosphoms) and two functions (calcium mobilization and phosphate mobilization). It would appear that a specific correction of the signal would not be possible. However, the calcium signal causes parathyroid secretion thus parathyroid hormone accompanies 1,25-(OH)2D3 in this circumstance, permitting mobilization of bone calcium and renal reabsorption of calcium. The effect of 1, 2S-(0H)2D3 on serum phosphate is negated by the parathyroid hormone induced loss of phosphate in urine. The composite effect of the low calcium signal is to elevate serum calcium but not phosphate ... 

The retention behavior of phosphatidic acid methyl esters (C15-C20) was studied on a C18 column (I = 208 nm) using a 70/22/8 acetonitrile/methanol/water (5 mM tetraalkyltriethylammonium phosphate) mobile phase [1184], A number of quaternary alkyltriethylammonium phosphates (pentyl, hexyl, heptyl, octyl, and dodecyl) were tested as the mobile phase modifier. The pentyl gave the best separation. Capacity factors were tabulated for all analytes in all mobile phases. Peaks were not well resolved, indicating that a gradient might have given better results. 

Diltiazem and eight metabolites (e.g., diltiazem sulfiixide, iV-demethyldeacetyl-Hiltiawm deacetyldiltiazem, C>-demethyldeacetyldiltiazem) were extracted from liver mocrosomes and well resolved on a column (A = 240 nm) using a 53/47 acetonitrile/water (15 mM ammonium phosphate) mobile phase [1495]. Peak shapes were excellent and elution was complete in 16 min. 

Xanthine, creatine, allantoin, oxonic acid, uric acid, and hypoxanthine were extracted from poultry litter and separated on a Cjg column (A = 200 nm, 215 nm, 235 nm, 290 nm). Elution was complete in 25 min using an aqueous 50 mM monobasic potassium phosphate mobile phase [1575]. Xanthine and hypoxanthine were poorly resolved. Standards of 20 mg/mL with 20 pL injections were easily detected. 

For the analysis of proteins modified with polyethylene glycol (PEG), it was seen that the addition of 10% ethanol to a sodium chloride/phosphate mobile phase improved column performance and longevity [42],... 

Plant-mierobial association is made up by strain of alfalfa nodulating baeteria Sinorhizobium meliloti S3, strain of phosphate mobilizing bacteria Serratia plymuthica 57 and alfalfa cultivars Medicago saliva L.) withstanding soil contamination with crude oil, diesel fuel and industrial oil. 

The objects of studies were strain of nodulating bacteria S. meliloti S3, strain of phosphate-mobilizing bacteria S, plymuthica 57, alfalfa (Mc<7/cago sativa L.), sod-podzol soil (humus - 2.38%, pH - 6.0, P2O5- 172 mg/kg soil, K O - 147 mg/kg soil, hydrolytic acidity - 1.82 mg/eq./100 g soil, total absorbed bases - 0.11 mg/eq./100 g soil), oil and derived products. 

Plant-microbial association 5. meliloti S3 +5. plymuthica SI +M. sativa may be applied for remediation of soil polluted with petroleum, industrial oil and diesel fuel. Tbe performed studies have shown that microbial treatment of alfalfa seeds intensified degradation of 1% crude oil in sod-podzol soil (Figure 12.1). Inoculation of alfalfa seeds with nodulating bacteria S. meliloti S3 accelerated oil decomposition (after 3 months) by 13.8% as compared to the control. Exposure of alfalfa seeds to phosphate-mobilizing bacteria S. plymuthica 57 and arbuscular mycorrhizal fungi (AMF) increased the rate of crude oil decay in soil by 28.4% and 22.7%, respectively. Maximal efficiency of petroleum disposal was achieved by plant-microbial association S. meliloti S3 + S. plymuthica 57 +M. sativa realizing the fastest process (58.47% up the control). 

Alfalfa is an excellent natural phytoextracting cultivar with respect to various pollutants. Increased share of leaves in oveigroimd part of the plant indicates efficiency of phytoevaporation as one of soil phytoremediation techniques. The foliage area of alfalfa plants in control variant equaled 43.3%. In experiments with soil introduction of industrial oil in concentrations 1 L/m and 3 L/m and seed treatment with nitrogen-fixing bacteria S. meliloti S3 and phosphate-mobilizing cultures S. plymutica 57 the leaf area rose to 49.2 and 52.5%, respectively. 

Egorshina, A. A., Khairullin, R. M., Lukyantsev, M. A., Kuramshina, Z. M., Smirnova, Y V. Phosphate-Mobilizing Activity of the Endophytic Bacillus subtihs Strains and their Effect on Wheat Roots Micorrhization Ratio. Scientific Journal of Siberian Federal University. Krasnoyarask, 2011,1,172-182. 

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