Gene/Protein
Disease
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Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
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Target Concepts:
Gene/Protein
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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)
Perphenazine enanthate has been used in wild animals as a tranquilizer during the period of adaptation to new environments to reduce stress, mortalities and injuries. A gas chromatographic procedure for the quantitative measurement of perphenazine in otter urine has been developed and validated. The method involved an enzymatic hydrolysis with
beta-glucuronidase
-arylsulfatase from Helix pomatia, followed by a solid-phase extraction with Bond Elut Certify cartridges. The resulting organic phase was evaporated, and the dry extract was derivatised with MSTFA to form the O-TMS derivative. The derivatised extracts were analysed by gas chromatography-mass spectrometry using
SIM
acquisition mode, measuring three diagnostic ions (m/z 246, 372 and 475). Another phenothiazine derivative, fluphenazine, was used as the internal standard (I.S.). Extraction recoveries for perphenazine and I.S. were 87.6 +/- 8.2% (n=4) and 106.7 +/- 13.4% (n=4), respectively. The calibration curves were linear in the range from 4 to 100 ng/ml (r2=0.99). The limits of detection and quantification were estimated as 1.2 and 3.5 ng/ml, respectively. Precision and accuracy obtained in intra-assay studies were in the ranges of 1.3-8.7 and 1.7-19.5%, respectively, using control samples containing 6, 16 and 60 ng/ml of perphenazine. In inter-assay experiments, precision ranged from 4.3 to 14.9% and accuracy from 3.1 to 11.8%. Examples of the application of the perphenazine quantification method in otter urines after administration of perphenazine enanthate are presented.
...
PMID:Quantification of perphenazine in eurasian otter (Lutra lutra lutra) urine samples by gas chromatography-mass spectrometry. 1193 97
A method of analysis was developed to determine free and glucuronated monobutyl phthalate (BuP) and monobenzyl phthalate (BeP) in urine for the assessment of exposure of man to butylbenzyl phthalate (BBP) in the workplace and in the environment. This method has also been applied in pharmacokinetic studies in experimental animals and the determination in urine of exposed workers. Urine samples are first subjected to enzymatic hydrolysis with
beta-glucuronidase
to enable the measurement of the total amount of monophthalates excreted. A fraction of the hydrolysate is used for further analysis. Monohexyl phthalate is added as an internal standard and the hydrolysed urine extracted with a n-hexane/dichloromethane mixture after acidification and saturation with salt. The organic fractions are washed, dehydrated and evaporated. The residue is methylated by means of diazomethane dissolved in diethylether, evaporated and further purified by extraction into n-hexane from an alkaline buffer. The organic fractions are evaporated and the residue redissolved in acetonitrile for analysis by ion trap GC-MS equipped with a 50 m apolar WCOT capillary column. TIC mass chromatograms are recorded from which
SIM
chromatograms can be derived electronically. The m/z values used are 91, 149, and 163 which provide a sufficient sensitive response and which are specific enough to pick up the methylated monophthalates under investigation. The quantitative limit of detection (LOQ) is 60 micrograms/L for BuP and BeP when using the Magnum ion Trap detector and 3 micrograms/L when using the Polaris Q in the splitless mode. The calibration curve in urine is linear from 120 micrograms/L to 50,000 micrograms/L with a coefficient of variation of less than 10%. In case of the Polaris Q linearity started from 10 micrograms/L. The recovery of the method is monitored by the response signal of the internal standard in the ion chromatogram. In the event of insufficient recovery the analysis is repeated. Variations in recovery are compensated by the internal standard of which the molecular structure is very similar to the ones of the monophthalates under investigation.
...
PMID:[Determination of monoester metabolites of butylbenzyl phthalate (BBP) by GC-MS in the urine of exposed workers]. 1197 37
Hydroxycinnamic acids are a group of phenolic compounds that exhibit a wide range of in vitro chemoprotective and antioxidant properties. Cereals containing a high proportion of the bran layers are rich in ester-linked hydroxycinnamic acids, such as ferulic and diferulic acids. The present work investigated the absorption in humans of hydroxycinnamic acids from high-bran breakfast cereal (wheat). Plasma and urine samples from six volunteers were collected before and after cereal consumption and analyzed for total hydroxycinnamic acids content after
beta-glucuronidase
/sulfatase treatment both by HPLC-DAD and by LC-MS (
SIM
monitoring). High-bran cereal administration resulted in increased plasma ferulic and sinapic acid concentrations (maximum levels detected of approximately 200 and approximately 40 nM, respectively) with absorption peaks between 1 and 3 h. Increases of approximately 4-fold in ferulic acid and approximately 5-fold in feruloylglycine were detected in 24-h urine after consumption of the cereal. Most of the ferulic acid detected in urine and plasma was present as conjugates (feruloylglycine and/or glucuronides). Diferulic acids were undetectable. The data show that ferulic and sinapic acids are taken up in humans from dietary high bran wheat but that absorption is limited and may originate only from the free and soluble portions present in the cereal.
...
PMID:Absorption of hydroxycinnamates in humans after high-bran cereal consumption. 1312 15
A simple, rapid and sensitive method was developed for determining the presence of seven anabolic steroids (boldenone, nandrolone, testosterone, methyltestosterone, epiandrosterone, androsterone, and atnozolol) in human urine. Glucuronide-conjugates of these compounds were hydrolyzed with
beta-glucuronidase
. The anabolic steroids were analyzed by on-line in-tube solid-phase microextraction (SPME) coupled with liquid chromatography-mass spectrometry (LC-MS). The steroids were separated within 14 min by high performance liquid chromatography using a Chromolith RP-18e column and 5 mM ammonium formate/methanol (35/65, v/v) as a mobile phase at a flow rate of 1.0 mL/min. Electrospray ionization conditions in the positive ion mode were optimized for the MS detection of these compounds. The optimum in-tube SPME conditions were 20 draw/eject cycles with a sample size of 40 microL using a Supel-Q PLOT capillary column for the extraction. The extracted compounds could be desorbed readily from the capillary column by flow of the mobile phase, and no carryover was observed. Using the in-tube SPME LC-MS with
SIM
mode detection, good linearity of the calibration curve (r>0.995) was obtained in the concentration range of 0.5-20 ng/mL, except for stanozolol. The detection limits (S/N=3) of anabolic steroids were in the range 9-182 pg/mL and the proposed method showed 20-33-fold higher sensitivity than the direct injection method. The within-day and between-day precisions were below 4.0% and 7.3% (n=5), respectively. This method was applied successfully to the analysis of urine samples without the interference peaks. The recovery rates of anabolic steroids spiked into urine samples were above 85%. This method is useful to analyze the urinary levels of these compounds in anti-doping tests.
...
PMID:Determination of anabolic steroids in human urine by automated in-tube solid-phase microextraction coupled with liquid chromatography-mass spectrometry. 2023 87