Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.31 (beta-glucuronidase)
 7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A method was developed for the quantitative analysis of catechol and 4-methylcatechol in human urine. [U-14C]Catechol was used as in internal standard. Urine was treated with beta-glucuronidase and sulphatase, acidified and extracted with ether. The ether extract was silylated and analysed by glass capillary gas chromatography. Catechol and 4-methylcatechol occurred in urine primarily as conjugates. Levels of catechol and 4-methylcatechol in the urine of nonsmokers on unrestricted diets were 10 +/- 7.3 (mean +/- 1 SD) and 3.4 +/- 2.3 mg/24 hr, respectively. Nonsmokers on uniform restricted diets, in which the intake of plant-derived products was limited, excreted 4.4 +/- 1.2 mg catechol and 8.1 +/- 1.7 mg 4-methylcatechol/24 hr. Smokers on the same restricted diet excreted 6.8 +/- 3.0 mg catechol and 6.1 +/- 2.6 mg 4-methylcatechol/24 hr. These results indicate that diet is a major factor in determining urinary catechol levels and that the contribution of smoking is comparatively small. Catechol and 4-methylcatechol appear to have different dietary precursors.
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PMID:Quantitative analysis of catechol and 4-methylcatechol in human urine. 689 May 13

Catechol estrogens such as 2-OH estrone are interesting estrogen metabolites formed in several human tissues and excreted in urine. We developed and thoroughly validated a radioimmunoassay for urinary 2-OH estrone that has several advantages over published RIAs. Because we developed a relatively specific antiserum, we did not include a preliminary chromatographic step to eliminate cross-reacting urinary steroids. We hydrolyzed urinary steroid conjugates with beta-glucuronidase from Helix pomatia because recoveries after acid hydrolysis were only 49.6% compared with 73.8% after enzyme hydrolysis. Published RIAs for urinary 2-OH estrone use acid hydrolysis. Our RIA measured 2-OH estrone independently of the volume of sample, and the detection limit was between 100 and 240 ng/L (10-24 pg per tube). The ED50 was 370 ng/L, and inter- and intraassay CVs for low, medium, and high concentrations were 22.5%, 22.8%, and 19.9%, and 17.4%, 14.3%, and 10.8%, respectively. Median concentrations measured in 14 controls and 33 postmenopausal patients with breast cancer were 0.96 and 1.55 micrograms/g creatinine, respectively, but there was considerable overlap between values from controls and patients.
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PMID:Radioimmunoassay of 2-hydroxyestrone in urine. 828 49

Little is known about flavonoid metabolism and excretion in man. In the present study, the urinary excretion of a major flavonoid in wine, catechin, and its metabolites, were measured after nine human subjects each consumed 120 ml red wine (RW) on one day and de-alcoholized red wine (DRW) on a separate day. Both the RW and DRW contained 120 (SEM 3) micromol catechin (35 mg). GC-MS analyses of the trimethylsilylated derivatives of catechin and 3' and 4' methylcatechin were performed before and after hydrolysis of conjugates by beta-glucuronidase and sulfatase. Baseline urine samples collected prior to wine consumption contained 0.013 (SEM 0.005) micromol catechin and metabolites. During the 8 h period following consumption of RW and DRW, 6.6 (SEM 0.9) and 5.3 (SEM 0.6) micromol catechin and metabolites were excreted in 893 (SEM 94) and 740 (SEM 101) ml urine respectively. This corresponded to 3.0-10.3% of the dose after RW and 2.1-8.2% of the dose after DRW. The amount of catechin and metabolites excreted in urine was 20% higher after RW compared with DRW (P=0.06). Catechin in all urine samples was present as metabolites and there were no differences in the proportions of individual metabolites after RW and DRW. As with other flavonoids, the fate of most ingested catechin is not yet known.
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PMID:Urinary excretion of catechin metabolites by human subjects after red wine consumption. 1189 12