Conjugation glucuronide

GLUCURONATE, A PRECURSOR OF PROTEOGLYCANS CONJUGATED GLUCURONIDES, IS A PRODUCT OF THE URONIC ACID PATHWAY... 

The main metabolite of DDT found in the liver and fats of mammals is its first dehydrochlorination product DDE, along with the unchanged DDT. A second step may occur leading to the oxidative dehydrochlorination of DDE to the substituted acid DDA, p.p -dichlorodiphenylacetlc add (Fig. 2). This metabolite is excreted as the conjugate glucuronide. 

Glutathione depletion can occur in malnourished people and alcoholics. The dominant metabolic pathway in neonates and children is sulphate conjugation. Glucuronide conjugation matures more slowly (the urinary glucuronide to sulphate ratio increases throughout childhood from 0.4 in neonates to 2 in adults) [7]. 

Disposition in the Body. Incompletely absorbed after oral administration. It is metabolised by debromination to bromo-benzarone and benzarone which are both active metabolites. About 50% of a dose is excreted in the bile as free and conjugated (glucuronide) metabolites and less than 10% of a dose is excreted in the urine. 

Disposition in the Body. Extensively metabolised mainly by hydrolysis and A -demethylation and excreted in the urine as free and conjugated (glucuronide) metabolites. 

In adults, virtually all bilirubin excreted in bile is in the form of glycosidic conjugates glucuronides account for 95% of them and glucosides and xylosides constitute the remainder. Of the glucuronides, diglucuronide is the major fraction ( 90%) and monoglucuronide the minor fraction (-10%). 

MRP2 GSH conjugates, glucuronides, sulfate conjugates, methotrexate, temocaprilat, CPT11 carboxylate, SN38 carboxylate, cisplatin, pravastatin MK571, cyclosporin A... 

N-oxidation/S-oxidation Dihydroxylation Dehydrogenation or reduction Demethylation Deethylation Depropylation Oxidative deamination Oxidative dechlorination Oxidative defluorination Hydration Methyl to an acid Conjugation Glucuronidation Sulfation... 

It should be mentioned that, with the exception of a few moderately important cases (e.g., GC of estrogen glucuronides after permethylation of both the steroid and the carbohydrate moieties), steroid conjugates (glucuronides or sulfates) are chromatographed as the free steroids after solvolytic or enzymatic hydrolysis. 

Rhepoxynius abronius 0.0018 BaP-7,8-diol, BaP-9, 10-diol, 9-hydroxyBaP, 3-hydroxyBaP, quinones, sulphated conjugates, glucuronides Protein adducts 0.0005 Reichert et al. (1985) ... 

Conjugation reactions consist of glucuronide formation, sulphate conjugation, methylation, acylation, and glutathione conjugation. Glucuronide formation is an important pathway in the metabolism of phenols, carboxylic acids, and long... 

In a human clinical trial, the administration of 148 mg of procyanidins had increased plasma epicatechin at 2 h compared to baseline (0 h) [33]. In addition, plasma epicatechin concentration increased to 21.2 nmol/L after consumption of the procyanidins and then returned to normal levels [33]. Similarly, plasma procyanidin dimer, (-)-epicatechin and (-i-)-catechin can be detected as early as 0.5 h and reach maximal concentrations by 2 h after acute consumption of cocoa [36]. Murphy et al. [1] indicated that administration of procyanidins increased plasma (-)-epicatechin and (-i-)-catechin by 81 % and 28 %, respectively. Moreover, (-)-epicatechin was detected as early as 0.5-1 h after chocolate or cocoa consumption and they are present mainly as sulfate conjugates, glucuronides, or methylated forms [89]. A study related to plasma kinetics of epicatechin in men after consumption of 40 and 80 g of dark chocolates, detected that epicatechin increased markedly after chocolates consumption, reaching a maximum between 2 and 3 h [90]. The maximal concentration and AUC of plasma kinetics correlate well with... 

Figure 1 Scheme for solvent extraction with control of pH. After three extractions, neutral compounds remain in the ether phase. This might be followed by hydrolysis with enzyme, acid, or base to break conjugates (glucuronide, sulfate) and repeated extractions (69). 

Glucuronides Sulfates Mainly mixed conjugates Glucuronide 5-position Glucuronide sulfate Mixed conjugates Glucuronide 5-position Mainly glucuronide Not detected except after black tea consumption Mainly sulfate... 

Metabolism. Pentachlorophend is conjugated with glucuronic add to form glucuron-ides. Newborn animab, which lack the ability to conjugate glucuronides, are more susceptible to pentachlorophend than adult animab. 

Free and conjugated (glucuronide, sulphate, or unidentified). 1,2,3,5- and 1,2,4,5-TeCB have not been separated. 

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