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

Disinfection of drinking water has been one of the greatest public health successes. Numerous halogenated disinfection by-products (DBPs) occur and chronic ingestion has been associated with an increased risk for colorectal cancer in human populations. Because the intestinal microbiota can bioactivate xenobiotics, studies have been performed to examine the effects of individual DBPs on intestinal microbial metabolism. No studies have been conducted on a defined mixture of DBPs to determine if there is an enhancement of response to a mixture. Ten-week-old male Long-Evans rats were treated in their drinking water for 17 weeks with 0.4 g/l potassium bromate, 1.8 g/l chloroform, 0.7 g/l bromodichloromethane (BDCM), 0.07 g/l 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), or a mixture of the four chemicals or distilled water. Cecal nitroreductase (NR), azoreductase (AR), dechlorinase (DC), beta-glucuronidase (GLR), beta-galactosidase (GAL), and beta-glucosidase (GLU) were assayed. No change in GLU or GLR activity was detected after treatment. BDCM treatment reduced DC and GAL activities and elevated NR and AR activity. GAL, AR, and NR activities were significantly different after treatment with bromate, chloroform, BDCM, and MX, but not the mixture. DC activity after chloroform-, MX-, or BDCM-treatment was significantly below control levels. The present study shows that changes in intestinal microbial metabolism do occur after treatment with individual and a mixture of DBPs but the changes were not additive in the mixture group.
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PMID:Changes in cecal microbial metabolism of rats induced by individual and a mixture of drinking water disinfection by-products. 1474 30

Sesamin, the major sesame oil lignan, is recognized for its health-promoting effects, including the lowering of cholesterol and elevation of gamma-tocopherol in rats and humans. However, little is known about the absorption and metabolism of sesamin in humans. In this study, 6 healthy volunteers took a single dose of sesame oil (508 micromol sesamin) and their urine was collected for four 12-h periods. The urine samples were treated with beta-glucuronidase/sulphatase and extracted with chloroform. The major urinary sesamin metabolite in the chloroform extract was collected using HPLC diode array detector and characterized as (1R,2S,5R,6S)-6-(3,4-dihydroxyphenyl)-2-(3,4-methylenedioxyphenyl)-3,7-dioxabicyclo-[3,3,0]octane using NMR and mass spectroscopy. A quantitative (1)H-NMR technique, based on the methylenedioxyphenyl protons signal (delta 5.91), was used for the quantification of the metabolite in the chloroform extracts of urine. The excretion of the sesamin catechol metabolite ranged from 22.2 to 38.6% (mean +/- SD, 29.3 +/- 5.6) of the ingested dose and happened mainly in the 1st 12 h after ingestion.
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PMID:Quantitative NMR analysis of a sesamin catechol metabolite in human urine. 1737 58

To search for the chemical constituents possessing anti-inflammatory or cytotoxic activities from plants, Morus wittiorum was investigated for the first time. The stem bark of M. wittiorum was extracted with 95% EtOH. The EtOH extract was fractionationed on silica gel by eluting with petroleum ehter, CHCl3 and EtOAc successively. The further isolation and purification of the EtOAc fraction of 95% EtOH extract was performed by various column chromatography such as silica gel, Sephadex LH-20, RP-C18 column chromatography and so on. The structures of compounds were determined on the basis of spectral analysis such as NMR, MS etc. As a result, nine compounds were isolated including six flavonoids and three stilbenoids and elucidated as quercetin (1), 5, 7, 3', 4'-tetrahydroxy-3-methoxyflavone (2), norartocarpanone (3), dihydrokaempferol (4), euchrenone a7 (5), morachalcone A (6), resveratrol (7), oxyresveratrol (8), 4'-prenyloxyresveratrol (9). Compounds 1-9 were isolated from this plant for the first time, among which compounds 1-8 were evaluated for their anti-inflammatory and cytotoxic activities, respectively. Wherein compounds 6 and 8 showed inhibition to the release of beta-glucuronidase from rat polymorphonuclear leukocyte (PMNs) induced by platelet activating factor (PAF) at a concentration of 10(-5) mol x L(-1). The inhibitory ratios were 76.8%, 94.2% individually. Compounds 2 and 8 exhibited selective cytotoxicity agaist human ovarian cancer (A2780) and human gastric cancer (BGC-823) with IC50 values as 0.66, 1.31 micromol x L(-1) individually.
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PMID:[Phenolic constituents from stem bark of Morus wittiorum and their anti-inflammation and cytotoxicity]. 2124 22


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