Results 151 to 160 of about 2,511,484 (202)

Quantitation of homogentisic acid in normal human plasma

Biomedical Applications, 1996
A new stable isotope dilution gas chromatograph-mass spectrometric method of analysis of homogentisic acid is described. Using this method, homogentisic acid is measured for the first time in normal human plasma. The assay of sera from nine normal individuals yielded a range of values from 2.4 to 12 ng/ml.
John C Deutsch, J C Deutsch
exaly   +3 more sources

The production of homogentisic acid out of phenylacetic acid byAspergillus niger

Antonie Van Leeuwenhoek, 1951
With the aid of the replacement culture technique it was found that a strain ofAspergillus niger was able to produce homogentisic acid out of phenylacetic acid with a yield upto 15.7 % of the theoretical amount.
A J, KLUYVER, J C, VAN ZIJP
exaly   +3 more sources

Chemiluminescence during the oxidation of homogentisic acid

Russian Journal of Physical Chemistry A, 2011
Chemiluminescence (CL) that accompanies the autooxidation of homogentisic acid in the presence of an alkali was studied. Data on the red shift of the CL spectrum at increased medium polarity and the dependence of the luminescence intensity and light efficiency on the reagent concentration were obtained.
Yurii Tsaplev
exaly   +2 more sources

A Synthesis of Homogentisic Acid

Transactions of the Kansas Academy of Science (1903-), 1973
Homogentisic acid (2,5-dihydroxyphenylacetic acid) is the substance found in the urine in alcaptonuria, an inborn error of metabolism involving incomplete oxidation of phenylalanine and tyrosine (1). The urine of individuals afBicted with the disease turns dark owning to oxidation of the acid to substituted quinhydrone complexes.
openaire   +2 more sources

The bound form of homogentisic acid in alkaptonuric urine

Clinica Chimica Acta, 1962
Abstract 1. (1) In two cases of alkaptonuria chromatography of the patients' urine showed two spots differing in R F , but giving positive reactions characteristic for homogentisic acid. One of these substances, which is soluble in ether, is identical with homogentisic acid. 2.
B, SKARZYNSKI, M, SARNECKA-KELLER, J, FRENDO   +2 more
openaire   +2 more sources

Studies of alcaptonuria: Kinetics of homogentisic acid autoxidation

Archives of Biochemistry and Biophysics, 1960
Abstract Rates of oxygen uptake of homogentisic acid preparations have been studied manometrically. Commercially available tyrosinase preparations were found to be enzymically active but to have a negligible, if any, effect on homogentisic acid in 0.1 M phosphate buffers, pH 6.85.
R A, MILCH, H K, SCHIRMER
openaire   +2 more sources

The preparation and identification of various adducts of oxidized homogentisic acid and the development of a new sensitive colorimetric assay for homogentisic acid

Clinica Chimica Acta, 1971
Abstract Homogentisic acid was converted to 1,4-benzoquinone-2-acetic acid (BQA). BQA was shown to undergo adduct formation with a number of different compounds containing free amino or sulfhydryl groups, including diethylenetriamine (DET) and D-penicillamine.
T J, Lustberg, J D, Schulman, J E, Seegmiller   +2 more
openaire   +2 more sources

Microbial conversion of p-hydroxyphenylacetic acid to homogentisic acid

Canadian Journal of Microbiology, 1972
An unidentified bacterium degrades p-hydroxyphenylacetic acid by a pathway which involves homogentisic acid as an intermediate. Extracts of cells grown on p-hydroxyphenylacetic acid contain an enzyme that converts p-hydroxyphenylacetic acid to homogentisic acid.
openaire   +3 more sources

Homogentisic Acid Derivatives from Miliusa balansae

Journal of Natural Products, 2003
The new homogentisic acid derivatives miliusol (1b) and miliusolide (2) from Miliusa balansae were isolated and structurally determined by spectroscopic means. The relative configurations of the new 1b and its known acetate 1a were established. Furthermore, the symmetric ether bis(2-hydroxyphenyl)methyl ether 3, which was isolated for the first time ...
Do Thu, Huong, Christine, Kamperdick, Tran Van, Sung   +2 more
openaire   +2 more sources