scholarly journals PREPARATION OF TISSUE EXTRACTS FOR THE DETERMINATION OF MALIC ACID

1951 ◽  
Vol 188 (1) ◽  
pp. 97-100 ◽  
Author(s):  
Lawrence M. Marshall ◽  
Felix. Friedberg ◽  
William A. DaCosta
Keyword(s):  
Malic Acid ◽  
Tissue Extracts

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

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.

Determination of coenzyme A and acetyl CoA in tissue extracts

1969 ◽  
Vol 29 (2) ◽  
pp. 293-299 ◽  
Author(s):  
John B. Allred ◽  
David G. Guy
Keyword(s):  
Coenzyme A ◽  
Acetyl Coa ◽  
Tissue Extracts

scholarly journals Determination of Residues of Flumequine and 7-Hydroxyflumequine in Edible Sheep Tissues by Liquid Chromatography with Fluorimetric and Ultraviolet Detection

1998 ◽  
Vol 81 (3) ◽  
pp. 519-527 ◽  
Author(s):  
Jean-michel Delmas ◽  
Anne-marie Chape ◽  
Pascal Sanders
Keyword(s):  
Liquid Chromatography ◽  
Ethyl Acetate ◽  
Simultaneous Determination ◽  
Rapid Method ◽  
Active Metabolite ◽  
Fluorimetric Detection ◽  
Ultraviolet Detection ◽  
Tissue Extracts ◽  
Edible Tissues

abstract A simple, sensitive, and rapid method for simultaneous determination of residues of flumequine and its microbiologically active metabolite 7-hydroxyflumequine in 100 mg sheep edible tissues (muscle, liver, kidney, and fat) by liquid chromatography is reported. After liquid-liquid cleanup with ethyl acetate, tissue extracts were injected onto a Select B column. The 2 compounds were determined by ultraviolet and fluorimetric detection. The method was repeatable and reproducible for flumequine and 7-hydroxyflumequine in muscle, liver, kidney, and fat, with limits of detection below 2 and 3 μg/kg for flumequine and 7-hydroxyflumequine, respectively. Mean recoveries for flumequine were 90 ± 7, 82 ± 7,89 ± 5, and 82 ± 6% in muscle, liver, kidney, and fat, respectively. Mean recoveries for 7-hydroxyflumequine were 91 ± 2, 90 ± 4, 86 ± 3, and 84 ± 4% in muscle, liver, kidney, and fat, respectively.

A Method for the Determination of Extracellular Space with 3H Inulin

1967 ◽  
Vol 13 (11) ◽  
pp. 953-957 ◽  
Author(s):  
Somasundaram Addanki ◽  
F Dallas Cahill ◽  
Juan F Sotos
Keyword(s):  
Extracellular Space ◽  
Liquid Scintillation ◽  
Hot Water ◽  
Acid Extraction ◽  
Internal Standards ◽  
Extraction Procedures ◽  
Tissue Extracts ◽  
Tissue Homogenates ◽  
Different Tissues

Abstract A method for the extraction and quantitation of 3H inulin from tissues is described. This method does not require either combustion technics or time-consuming acid extraction procedures. Inulin is as soluble in the liquid scintillation medium as it is in water. Therefore, hot-water tissue extracts without further treatment were employed to quantitate 3H inulin. Nearly 100% recovery was obtained when different 3H inulin internal standards were added either to water or to tissue homogenates. The values obtained with this method for the extracellular space of different tissues of the rat agree with those reported in the literature.

scholarly journals Determination of D-Malic Acid in Apple Juice by Liquid Chromatography: Collaborative Study

1996 ◽  
Vol 79 (1) ◽  
pp. 50-54 ◽  
Author(s):  
Thomas A Eisele ◽  
K Adadevoh ◽  
G Anderson ◽  
A Brause ◽  
D Briesmeister ◽  
...  
Keyword(s):  
Malic Acid ◽  
Apple Juice ◽  
Copper Acetate ◽  
Collaborative Study ◽  
Reversed Phase ◽  
Uv Detector ◽  
Paired Samples ◽  
Study Results ◽  
Liquid Chromatographic

Abstract Eleven laboratories collaboratively studied a liquid chromatographic (LC) method for determination of D-malic acid in apple juice. The mobile phase consisted of 16 mM L-valine and 8 mM copper acetate adjusted to pH 5.5 with NaOH. The UV detector was set at 330 nm, and a single reversed-phase LC column was used. Seven paired samples containing various amounts of D-malic acid ranging from 0 to 188 mg/100 mL of 12 Brix pasteurized apple juice were tested by each collaborator. Repeatability and reproducibility coefficients of variation ranged from 1.0 to 3.5% and 7.7 to 11.7%, respectively, within the range of 26 to 188 mg D-malic acid/100 mL of 12 Brix apple juice. The collabora tive study results demonstrated that the method could quantitate the economic adulteration of ap ple juice with DL-malic acid at lower levels than those reported with previous methods. The LC method for determination of D-malic acid in apple juice has been adopted first action by AOAC INTERNATIONAL.

Fluorescent sensing layer for the determination of L-malic acid in wine

2007 ◽  
Vol 387 (6) ◽  
pp. 2297-2305 ◽  
Author(s):  
Félix Gallarta ◽  
Francisco Javier Sáinz ◽  
Cecilia Sáenz
Keyword(s):  
Malic Acid ◽  
Fluorescent Sensing
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