AN IMPROVED PREPARATIVE METHOD FOR D-ERYTHROSE 4-PHOSPHATE

1966 ◽  
Vol 44 (6) ◽  
pp. 663-669 ◽  
Author(s):  
A. S. Sieben ◽  
A. S. Perlin ◽  
F. J. Simpson

The oxidation of 1 mmole of D-glucose 6-phosphate with 1.7 mmoles of lead tetraacetate admixed with 1.8 mmoles of sulfuric acid yields a preparation containing 0.77 mmole of D-erythrose 4-phosphate and 0.20 mmole of unoxidized glucose 6-phosphate. The D-erythrose 4-phosphate is separated from the D-glucose 6-phosphate by chromatography on Dowex 1-formate, and recovered as the barium salt of the hydrazone in 50% yield. Evidence is presented that erythrose 4-phosphate may exist in monomeric and dimeric forms. Glucose 6-phosphate and erythrose 4-phosphate produce different colors in the phenol – sulfuric acid reaction. This can be used for the qualitative identification and quantitative determination of these sugar phosphates.

1968 ◽  
Vol 51 (3) ◽  
pp. 540-543
Author(s):  
John Wiskerchen

Abstract A colorimetric method for the quantitative determination of sodium lauryl sulfate in liquid, frozen, and powdered egg white was studied by eight collaborators. Determinations were made on flake and powdered egg white at levels of 0.05, 0.1, and 0.2% (w/w) and on liquid egg white at levels of 0.006, 0.0125, and 0.0250% (w/w) sodium lauryl sulfate. The egg white is dissolved in water, and the protein is precipitated with ethanol and removed by filtration. An aliquot of the filtrate is evaporated to dryness, and the residue is dissolved in water and acidified with sulfuric acid. The sodium lauryl sulfate is complexed with Azure A, extracted into chloroform, and determined spectrophotometrically at 637 mμ. A blank determination is made on another aliquot of the filtrate by complexing the sodium lauryl sulfate with benzethonium chloride. This is a stable colorless complex. Average recoveries in the collaborative study were 98—102% with a mean deviation of 2.8—5.4%. It is recommended that the method be adopted as official, first action.


2021 ◽  
Author(s):  
A.M. Tretyakova ◽  
N.A. Vakhnina

The possibility of using the phenol-sulfuric acid method for the determination of total glycogen, its acid-soluble and acid-insoluble fractions in the liver and skeletal muscles of rats was studied. It was found that the use of a precipitant in the isolation of total glycogen and its fractions increases the yield of the investigated substances. Key words: phenol-sulfate method, rats, liver, muscles, total glycogen, acid-soluble glycogen, acid-insoluble glycogen.


2018 ◽  
Vol 71 (4) ◽  
pp. 285
Author(s):  
Graham S. Chandler ◽  
Wolfgang H. F. Sasse

The quantitative determination of the products of bromination of acridine in concentrated sulfuric acid and glacial acetic acid is described. In both cases, the only monobromo products were the 2- and 4-substituted compounds. With sulfuric acid, the 4-isomer predominates whereas in acetic acid, the 2-isomer is predominant. This work expands substantially on the tiny amount of previous work on halogenation of dibenzo-annelated pyridines.


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