Hydrolysis of 2-Chloroethyl Palmitate and 2-Chloroethyl Linoleate by Mammalian Enzymes

1981 ◽  
Vol 44 (2) ◽  
pp. 112-114 ◽  
Author(s):  
JOHN J. SULLIVAN ◽  
JOHN J. MAJNARICH
Keyword(s):  
Liquid Chromatography ◽  
Gastric Juice ◽  
Pancreatic Juice ◽  
Hydrolytic Activity ◽  
Gas Liquid Chromatography ◽  
Pig Liver ◽  
Hydrolysis Constants ◽  
Artificial Gastric Juice ◽  
Liver Homogenates ◽  
Hydrolysis Of

Hydrolysis of 2-chloroethyl palmitate and 2-chloroethyl linoleate was studied in artificial gastric juice, artificial pancreatic juice, pig liver homogenates and pig intestine homogenates. Hydrolytic activity was followed by gas-liquid chromatography. Substantial hydrolysis was observed in all preparations except the artificial gastric juice. Hydrolysis constants ranged from <0.001 min−1 in the gastric juice to 0.064 min−1 for the linoleate ester in the pancreatic juice.

GLC Determination of Ethopabate in Chicken Tissues by Derivative Formation

1970 ◽  
Vol 53 (3) ◽  
pp. 461-464
Author(s):  
P R Handy ◽  
F J Holzer
Keyword(s):  
Liquid Chromatography ◽  
Electron Affinity ◽  
Gas Liquid Chromatography ◽  
Chicken Tissues ◽  
Cleanup Procedure ◽  
Hydrolysis Of

Abstract The published method for the determination of ethopabate residues in chicken tissues has been improved by formation of the 2,4- dinitrophenyl derivative of m-phenetidine, which is produced by hydrolysis of ethopabate. The derivative is suitable for gas-liquid chromatography, using an electron affinity detector, and allows a simpler cleanup procedure. The sensitivity of the method is about 0.05 ppm; average recoveries at 0.5 ppm range between 66 and 97% for all tissues.

Gas-Liquid Chromatographic Determination of Residues of Chlorpyriphos and Leptophos, Including their Major Metabolites, in Vegetable Tissue

1974 ◽  
Vol 57 (1) ◽  
pp. 182-188 ◽  
Author(s):  
Heinz E Braun
Keyword(s):  
Liquid Chromatography ◽  
Chromatographic Determination ◽  
Gas Liquid Chromatography ◽  
Aqueous Sodium ◽  
Hydrolysis Products ◽  
Aqueous Sodium Carbonate ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic ◽  
Hydrolysis Of

Abstract A method is described for the determination of residual chlorpyriphos (O, O-diethyl 0-3,5,6- trichloro- 2 - pyridyl phosphorothioate) and leptophos (O-(4-bromo-2,5-dichlorophenyl) O-methyl phosphonothioate), and their respective oxygen analogs and hydrolytic metabolites, in field-treated vegetables. Samples are extracted by blending with acetonitrile followed by liquid-liquid partitioning between benzene and aqueous sodium carbonate to separate the parent compounds and oxygen analogs from the hydrolytic metabolites. Both fractions are individually cleaned up on silica gel which also serves to fractionate the parent compounds from their oxygen analogs as the result of oncolumn hydrolysis of the oxygen analogs. Chlorpyriphos and leptophos are determined by flame photometric gas-liquid chromatography (GLC); the residual and derived hydrolysis products are derivatized with trimethylsilyl acetamide and determined by electron capture GLC. Overall recoveries from fortified samples averaged 95% for the parent compounds and 85% for the oxygen analogs and hydrolytic metabolites. Detection limits approximated 0.005 ppm for chlorpyriphos and leptophos, 0.002 ppm for the oxygen analogs, and 0.001 ppm for the hydrolytic metabolites.

scholarly journals INFLUENCE OF HYDROLYTIC TREATMENT ON THE CONTENT OF REDUCING SUBSTANCES IN NEUTRAL-SULPHITE ALKALI

2021 ◽  
pp. 309-317
Author(s):  
Leysan Azatovna Mingazova ◽  
Yelena Vyacheslavovna Kryakunova ◽  
Zosia Albertovna Kanarskaya ◽  
Альберт Владимирович Kanarskiy ◽  
Igor' Vadimovich Kruchina-Bogdanov ◽  
...  
Keyword(s):  
Liquid Chromatography ◽  
Enzymatic Hydrolysis ◽  
Acid Hydrolysis ◽  
Dry Matter ◽  
Gas Liquid Chromatography ◽  
Birch Wood ◽  
Carbohydrate Composition ◽  
Enzyme Preparations ◽  
Reducing Substances ◽  
Hydrolysis Of

The aim of this work is to develop a technology for the preparation of neutral-sulfite liquors formed during the production of fibrous semi-finished products - cellulose from birch wood - for subsequent use as a nutrient medium for the cultivation of microorganisms. Acid hydrolysis was carried out at a temperature of 100 °С at a ratio of a 10% sulfuric acid solution to a liquor sample of 1 : 1. Enzymatic hydrolysis of neutral sulfite liquors was carried out with the enzyme preparations Accellerase XY and Accellerase XC at 50±2 °C and 60±2 °C. The end of hydrolysis was determined by the cessation of the increase in the content of reducing substances (RS) in the hydrolyzate. The original neutral sulphite lye contained 9.4% dry matter, 21.7 g/l of reducing substances, pH 5.3±0.2. It has been shown that as a result of enzymatic hydrolysis, the content of insoluble dry residue in the hydrolyzate decreases to 8.32% and 8.41%, respectively, and during acid hydrolysis – to 7.8%. The content of RS in neutral sulfite lye after acid hydrolysis increases by an average of 3 times, while after enzymatic hydrolysis - a maximum of 2 times. It was found by gas-liquid chromatography that pentoses predominate in the obtained hydrolysates. Microbiological processing of media with a similar carbohydrate composition is possible by a number of strains of microorganisms capable of assimilating pentoses, for example, yeast-like fungi of the Saccharomycetaceae family and bacteria of the Enterobacteriaceae family.

Mono-O-(methylsulfonylethy)-d-glucoses

1967 ◽  
Vol 45 (3) ◽  
pp. 255-260 ◽  
Author(s):  
A. L. Bullock ◽  
V. O. Cirino ◽  
S. P. Rowland
Keyword(s):  
Liquid Chromatography ◽  
Acid Hydrolysis ◽  
Gas Liquid Chromatography ◽  
Vinyl Sulfone ◽  
Methyl Vinyl ◽  
Trimethylsilyl Derivatives ◽  
Hydrolysis Of ◽  
Methyl Vinyl Sulfone ◽  
Glucose Derivatives

Mono-O-(methylsulfonylethyl)-d-glucoses needed for comparison with the cleavage products obtained by acid hydrolysis of methyl vinyl sulfone modified cotton celluloses have been prepared. Several new glucose derivatives were prepared as intermediates in the synthesis of the desired 2-O-, 3-O-, and 6-O-(methylsulfonylethyl)-d-glucoses. The reactions were monitored by gas–liquid chromatography; use was made of trimethylsilyl derivatives as necessary. The substituted glucoses were obtained as glassy solids.

Metabolism of amphetamines by Mycobacterium smegmatis

1980 ◽  
Vol 26 (3) ◽  
pp. 343-349 ◽  
Author(s):  
Ronald T. Coutts ◽  
Brian C. Foster
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Mycobacterium Smegmatis ◽  
Alkyl Substituent ◽  
Acetyl Derivative ◽  
The Other ◽  
Gas Liquid Chromatography ◽  
Considerable Influence ◽  
Hydrolysis Of ◽  
Oxygenated Products

Amphetamine and five N-alkylated homologues were readily metabolized by Mycobacterium smegmatis and the products obtained were identified by gas–liquid chromatography and mass spectrometry. The N-alkyl substituent had a considerable influence on the degree and mechanism of biotransformation. With the exception of the N-isopropyl derivative, all of the N-alkylated homologues were dealkylated to amphetamine which was then conjugated to the N-acetyl derivative. The degree of N-oxygenation of these substrates was significantly different from that observed in mammalian and fungal systems where four products are generally recovered. Mycobacterium smegmatis N-oxygenation of amphetamine did not occur, whereas all N-alkylated amphetamines were converted to the corresponding nitrones or, in the case of methamphetamine, to 1-phenyl-2-propanone oxime. No other N-oxygenated products were isolated. Mycobacterium smegmatis metabolism of 1-phenyl-2-propanone oxime, N-hydroxyamphetamine. N-hydroxy-N-(n-propyl)amphetamine, and the nitrone, α-methyl-N-(n-propylidene) benzeneethanamine N-oxide, was also studied. Some hydrolysis of the oxime to 1-phenyl-2-propanone was observed. The other three substrates were metabolized to amphetamine and N-acetylamphetamine.

scholarly journals Spectrophotometric Determination of Fenpropathrin and Fluvalinate in Their Formulations

1999 ◽  
Vol 82 (4) ◽  
pp. 785-791 ◽  
Author(s):  
Nutan Kaushik ◽  
Swadesh Kumar Handa
Keyword(s):  
Liquid Chromatography ◽  
Spectrophotometric Determination ◽  
Alkaline Hydrolysis ◽  
Cyanogen Bromide ◽  
Gas Liquid Chromatography ◽  
Colored Complex ◽  
Precise Method ◽  
Hydrolysis Of

Abstract An economical and precise method for spectrophotometric determination of fenpropathrin and fluvalinate pyrethroids is reported. The method involves alkaline hydrolysis of the pyrethroids to release HCN, which is converted to cyanogen bromide to form a colored complex with benzidine-pyridine reagent. This method can be used effectively to determine actual concentrations of these pyrethroids in their formulations. Results are comparable with results obtained by gas-liquid chromatography.

Glucosinolates and Derived Products in Cruciferous Vegetables: Total Glucosinolates by Retention on Anion Exchange Resin and Enzymatic Hydrolysis to Measure Released Glucose

1977 ◽  
Vol 60 (4) ◽  
pp. 946-949 ◽  
Author(s):  
Cecil H VanEtten ◽  
Melvin E Daxenbichler
Keyword(s):  
Liquid Chromatography ◽  
Enzymatic Hydrolysis ◽  
Anion Exchange ◽  
Coefficient Of Variation ◽  
Methylene Chloride ◽  
Exchange Resin ◽  
Anion Exchange Resin ◽  
Gas Liquid Chromatography ◽  
Other Substances ◽  
Hydrolysis Of

Abstract Details are given for determining total glucoginolates in Cruciferae plants by a procedure measuring released glucose. The glucosinolates are separated from about 90% of other material in the plant extract by adsorption on an anion exchange resin. Then, by a selective thioglucosidase hydrolysis of the glucosinolates retained on the exchange resin, the glucose and aglucons are separated from other substances retained by the resin. Glucose is released into an aqueous medium and is equivalent to the total glucosinolates. The aglucons formed by the hydrolysis are extracted into methylene chloride and determined by gas-liquid chromatography. Based on 29 determinations of the glucose from sinigrin, analyzed under different conditions, accuracy of the total glucosinolate determination was 94.8 ± 7.3%. The coefficient of variation, determined by duplicate analyses on extracts from 58 cabbage samples, was 4.6%.

Separation and Micro Quantitative Determination of Dipterex and DDVP by Gas-Liquid Chromatography

1965 ◽  
Vol 48 (2) ◽  
pp. 374-379
Author(s):  
Abdel Rahman (Ali) El-Refai ◽  
Laura Giuffrida
Keyword(s):  
Liquid Chromatography ◽  
Simple Procedure ◽  
Gas Liquid Chromatography ◽  
Experimental Conditions ◽  
Rate Of Hydrolysis ◽  
Hydrolysis Of ◽  
Gas Chromatographic Separation ◽  
Sensitive Method ◽  
General Method

Abstract A simple, rapid, and sensitive method was required for the determination of Dipterex and DDVP in water and insecticidal formulations. Existing methods were found to he unsatisfactory. This paper describes a rapid method for the gas chromatographic separation and estimation of Dipterex and DDVP in macro and micro amounts. The sodium thermionic detector (STD) was used, and the GLC conditions are described. A general method for extraction of the two compounds from water solutions was developed and applied in studying the rate of hydrolysis of Dipterex and DDVP in river water. A simple procedure has been developed for analysis of formulations of Dipterex and DDVP. Several commercial formulations have been analyzed by this method with a precision of 1–2% obtained under experimental conditions.

Spontaneous hydrolysis of heroin in buffered solution

1978 ◽  
Vol 56 (4) ◽  
pp. 665-667 ◽  
Author(s):  
Paul T. Smith ◽  
M. Hirst ◽  
C. W. Gowdey
Keyword(s):  
Liquid Chromatography ◽  
Rate Constant ◽  
Phosphate Buffer ◽  
Internal Standard ◽  
Order Rate Constant ◽  
Gas Liquid Chromatography ◽  
First Order ◽  
Order Rate ◽  
Spontaneous Hydrolysis ◽  
Hydrolysis Of

Electron-capture gas–liquid chromatography was used to study the spontaneous hydrolysis of heroin in phosphate buffer (pH 6.4 and pH 7.4) at 23 °C. Aliquots of solution were taken over a 24-h period. After extraction at pH 8.9 into propan-2-ol (10%) – ethyl acetate, deacetylated products were made into heptafluorobutyrate derivatives which were analyzed quantitatively using nalorphine as the internal standard. Heroin decomposes to O6-monoacetylmorphine (O6-MAM) under these conditions. Further decomposition to morphine was not observed. Spontaneous hydrolysis was faster at pH 7.4 (first-order rate constant, 9.6 × 10−5 min−1) than at pH 6.4 (first-order rate constant, 3.0 × 10−5 min−1). In 24 h, the decomposition to O6-MAM was 13 and 4%, respectively.

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