SOLUBILITY OF IRON, ALUMINUM, CALCIUM, AND MAGNESIUM INOSITOL PHOSPHATES AT DIFFERENT pH VALUES

The effect of the homogenization procedure, the centrifugation scheme, and the composition of the suspension medium on the distribution of nuclear volumes has been studied.It has been shown that the Waring Blendor not only destroys a greater number of the nuclei during homogenization, but also that this destruction is a selective one. At neutral pH values, no direct relationship appears to exist between the DNA content of the nuclei and their density. For this reason, purification in concentrated sucrose solutions produces a selective loss of the lighter nuclei, which includes small diploid stromal nuclei and some of the larger polyploid type of parenchymal nuclei.The study of the effect of increasing the calcium and magnesium ion concentrations (from 0.001 to 0.005 M) on the nuclear distribution showed that these ions produce a selective shrinkage and condensation of the nuclei, probably through different mechanisms.

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USING MALIC ACID SOLUTIONS FOR THE HYDRATION OF VEGETABLE OILS AND LECITHIN PRODUCTION

Известия вузов. Пищевая технология ◽

10.26297/0579-3009.2020.1.9 ◽

2020 ◽

Author(s):

Л.А. МАРЧЕНКО ◽

Т.Н. БОКОВИКОВА ◽

Е.В. ЛИСОВАЯ ◽

С.А. ИЛЬИНОВА ◽

Е.П. ВИКТОРОВА

Keyword(s):

Malic Acid ◽

Complex Compounds ◽

Point Of View ◽

Magnesium Ions ◽

Ph Values ◽

Calcium And Magnesium ◽

The Stability ◽

The Cost ◽

Calcium And Magnesium Ions

Исследована возможность применения яблочной кислоты (ЯК) в качестве гидратирующего агента для перевода негидратируемых форм фосфолипидов в гидратируемые. Выбор ЯК обусловлен ее стоимостью, которая в 1,5 раза меньше стоимости янтарной кислоты, широко применяемой в качестве гидратирующего агента, а также большей доступностью с точки зрения промышленного производства. Исследование процесса комплексообразования и определение состава комплексных соединений ЯК с ионами кальция и магния осуществляли методом потенциометрического титрования. Установлено, что внесение в раствор ЯК ионов кальция и магния приводит к снижению значений рН, что свидетельствует о наличии комплексообразования в указанных системах. Наиболее устойчивыми являются комплексы ионов кальция и магния с непротонированным лигандом при соотношении Ме2 : лиганд 1 : 1. В процессе комплексообразования ионы Ca2 и Mg2 вытесняют протоны только карбоксильных групп ЯК, которая с ионами кальция образует более устойчивые комплексы, чем с ионами магния. Показано, что устойчивость комплексов ЯК с ионами кальция и магния значительно выше, чем устойчивость комплексов фосфатидилсеринов и фосфатидных кислот с указанными ионами. Использование водных растворов ЯК в качестве гидратирующего агента позволит повысить эффективность процесса гидратации и увеличить выход фосфолипидов и, следовательно, готового продукта лецитина. The possibility of using malic acid (MA) as a hydrating agent for converting non-hydrated forms of phospholipids into hydrated ones has been investigated. The choice of MA is due to its cost, which is 1,5 times less than the cost of succinic acid, as well as greater availability from the point of view of industrial production. The study of the complexation process and determination of the composition of complex compounds of MA with calcium and magnesium ions was carried out by the method of potentiometric titration. It was found that the introduction of calcium and magnesium ions into the MA solution leads to a decrease in pH values, which indicates the presence of complexation in these systems. Complexes of calcium and magnesium ions with an unprotected ligand at a ratio of ME2 : ligand 1 : 1 are the most stable. In the process of complexing, Ca2 and Mg2 ions displace protons only of the carboxyl groups of MA, which forms more stable complexes with calcium ions than with magnesium ions. It is shown that the stability of MA complexes with calcium and magnesium ions is significantly higher than the stability of phosphatidylserine and phosphatidic acid complexes with these ions. Using water solutions of MA as a hydrating agent will increase the efficiency of the hydration process and increase the yield of phospholipids and, consequently, the finished product lecithin.

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Treatment of cooling tower blowdown water containing silica, calcium and magnesium by electrocoagulation

Water Science & Technology ◽

10.2166/wst.2009.675 ◽

2009 ◽

Vol 60 (9) ◽

pp. 2345-2352 ◽

Cited By ~ 21

Author(s):

Z. Liao ◽

Z. Gu ◽

M. C. Schulz ◽

J. R. Davis ◽

J. C. Baygents ◽

...

Keyword(s):

Cooling Tower ◽

Target Species ◽

Organic Additives ◽

Dissolved Silica ◽

Ion Removal ◽

Ph Values ◽

Silica Removal ◽

Initial Ph ◽

Aluminum Electrodes ◽

Calcium And Magnesium

This research investigated the effectiveness of electrocoagulation using iron and aluminium electrodes for treating cooling tower blowdown (CTB) waters containing dissolved silica (Si(OH)4), Ca2 + and Mg2 + . The removal of each target species was measured as a function of the coagulant dose in simulated CTB waters with initial pH values of 5, 7, and 9. Experiments were also performed to investigate the effect of antiscaling compounds and coagulation aids on hardness ion removal. Both iron and aluminum electrodes were effective at removing dissolved silica. For coagulant doses ≤3 mM, silica removal was a linear function of the coagulant dose, with 0.4 to 0.5 moles of silica removed per mole of iron or aluminium. Iron electrodes were only 30% as effective at removing Ca2 + and Mg2 + as compared to silica. There was no measurable removal of hardness ions by aluminium electrodes in the absence of organic additives. Phosphonate based antiscaling compounds were uniformly effective at increasing the removal of Ca2 + and Mg2 + by both iron and aluminium electrodes. Cationic and amphoteric polymers used as coagulation aids were also effective at increasing hardness ion removal.

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Experimental study of aluminum-, calcium-, and magnesium-acetate complexing at 80°C

Geochimica et Cosmochimica Acta ◽

10.1016/0016-7037(91)90154-w ◽

1991 ◽

Vol 55 (4) ◽

pp. 955-964 ◽

Cited By ~ 58

Author(s):

Jeremy B. Fein

Keyword(s):

Experimental Study ◽

Magnesium Acetate ◽

Calcium And Magnesium ◽

Aluminum Calcium

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Phosphoester specificity of purified human liver alkaline phosphatase

Canadian Journal of Biochemistry ◽

10.1139/o79-124 ◽

1979 ◽

Vol 57 (7) ◽

pp. 1000-1007 ◽

Cited By ~ 8

Author(s):

L. E. Seargeant ◽

R. A. Stinson

Keyword(s):

Alkaline Phosphatase ◽

Atpase Activity ◽

Human Liver ◽

Magnesium Ions ◽

Calcium Dependent ◽

Ph Values ◽

Regulator Protein ◽

Calcium And Magnesium ◽

Hydrolysis Of ◽

Calcium And Magnesium Ions

Kinetic parameters for the hydrolysis of a number of physiologically important phosphoesters by purified human liver alkaline phosphatase have been determined. The enzyme was studied at pH values of 7.0 to 10.0. The affinity of the enzyme for the compounds was determined by competition experiments and by their direct employment as substrates. Phosphodiesters and phosphonates were not hydrolysed but the latter were inhibitors. Calcium and magnesium ions inhibited the hydrolysis of ATP and PP1 and evidence is presented to show that the metal complexes of these substrates are not hydrolysed by alkaline phosphatase. A calcium-stimulated ATPase activity could not be demonstrated for the purified enzyme or the enzyme in the presence of a calcium-dependent regulator protein. Nevertheless, the influence of magnesium and calcium ions on the ATPase activity of alkaline phosphatase means that precautions must be taken when assaying for Ca2+-ATPase in the presence of alkaline phosphatase.The low substrate Km values and the hydrolysis which occurs at pH 7.4 mean that the enzyme could have a significant phosphohydrolytic role. However, liver cell phosphate concentrations, if accessible to the enzyme, are sufficient to strongly inhibit this activity.

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LABORATORY AND GREENHOUSE STUDIES ON EFFECT OF LIME AND OTHER AMENDMENTS ON WATER-SOLUBLE BORON IN SOIL

Canadian Journal of Soil Science ◽

10.4141/cjss58-005 ◽

1958 ◽

Vol 38 (1) ◽

pp. 27-35 ◽

Cited By ~ 5

Author(s):

R. F. Bishop ◽

R. L. Cook

Keyword(s):

Sodium Hydroxide ◽

Soil Ph ◽

Laboratory Experiments ◽

Boron Content ◽

Magnesium Carbonate ◽

Water Soluble ◽

Plant Analysis ◽

Laboratory Studies ◽

Ph Values ◽

Calcium And Magnesium

Greenhouse and laboratory experiments were used to study the effect of various soil amendments on the water-soluble boron content of a strongly acid soil.In the greenhouse, using ladino clover as the test crop, liming reduced boron availability as measured by soil and plant analysis. Calcium-boron ratios in the clover ranged from approximately 550:1 to 2000:1 and there was a significant correlation between the water-soluble boron in the soil and the boron content of the clover.In the laboratory studies calcium and magnesium carbonates were equally effective in decreasing water-soluble boron in soil. Gypsum was ineffective. Manure or alfalfa hay increased the water-soluble boron content of soil in proportion to the amounts applied. Applications of sodium hydroxide, resulting in a range of soil pH values from 4.82 to 9.72, were accompanied by decreases in water-soluble boron until a pH of approximately 8.0 was reached. Above this point water-soluble boron increased. At comparable pH values of approximately 7.0 or less, sodium hydroxide caused a smaller reduction in water-soluble boron than did either calcium or magnesium carbonate.

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