Results 171 to 180 of about 5,440 (220)

Farnesyl-homogentisic acid derivatives from Otoba parvifolia

Phytochemistry, 1989
Abstract The seeds of Otoba parvifolia contain six novel compounds, apparently derived from homogentisic acid, including 3-farnesyl-2,5-dihydroxybenzaldehyde, 2-(1′-farnesyl-2′-hydroxy-5′-oxocyclohex-3′-en-1′-yl)-acetic acid lactone, 3-(1′-farnesyl-2′-hydroxy-4′-oxocyclopentan-1′-yl)-3-methoxy (and ethoxy) propanoic acid lactones and methyl esters.
A.Gilberto Ferreira, Mario Motidome, Otto R. Gottlieb, João B. Fernandes, Paulo C. Vieira, Miriam Cojocaru, Hugo E. Gottlieb   +6 more
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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
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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.
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Homogentisic acid interference in routine urine creatinine determination

Molecular Genetics and Metabolism, 2010
We report the artifactual elevation of homogentisic acid (HGA) in urine from alkaptonuric patients after replacing the creatinine method (Jaffe reaction) in our laboratory with an automated enzymatic method. Samples with elevated HGA by GC-MS had lower creatinine values as determined by the enzymatic method than by the Jaffe reaction.
Perry R, Loken, Mark J, Magera, Wendy, Introne, Silvia, Tortorelli, Dimitar, Gavrilov, Devin, Oglesbee, Piero, Rinaldo, Dietrich, Matern, Kimiyo, Raymond   +8 more
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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
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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

Purification of the homogentisic acid oxidase from mammalian liver

The International Journal of Biochemistry & Cell Biology, 1995
Alkaptonuria is a rare human autosomal recessive disease caused by the lack of homogentisic acid oxidase (HTO) activity. This enzyme, produced mainly in liver, has been purified and characterized from bovine liver. The aim of this work was to attempt a new purification approach for this enzyme from rabbit liver and to compare its characteristics with ...
S, Hudecová, Z, Straková, O, Krizanova
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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
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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.
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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
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