Oxidation of amino acids by peracetic acid: Reaction kinetics, pathways and theoretical calculations

α-Methyl-DL-tryptophan, injected intraperitoneally into rats, has a weight-depressing action lasting up to 72 hours. Dosages in the range 0.015–2.0 millimoles/kg body weight (3.3–436 mg/kg) are effective. Attempts to antagonize the weight-depressing action by giving essential amino acids and B vitamins were unsuccessful. Metabolic studies have shown that about half the injected dose of the compound (or its derivatives), as measured by the Hopkins–Cole glyoxylic acid reaction, is excreted in the urine in 24 hours; most of this appears during the first 4 hours after the injection. Ina search for an explanation for the weight-depressing action of α-methyltryptophan, tryptophan pyrrolase activity in the liver was estimated. This enzymic activity increases for 8 hours after the injection of α-methyltryptophan, and thereafter remains high for 72 hours. Tryptophan-injected animals showed increases in tryptophan pyrrolase level for 1.5 hours, and a return to normal concentrations within 24 hours. Other α-methyl amino acids which were tested had no comparable effect on body weight.

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HISTOCHEMICAL DIFFERENTIATION BETWEEN TYROSINE AND CHLOROGENIC ACID IN PLANT TISSUES I. NITROUS ACID REACTIONS AND METAL CHELATION OF NITROSOTYROSINE

Journal of Histochemistry & Cytochemistry ◽

10.1177/16.3.191 ◽

1968 ◽

Vol 16 (3) ◽

pp. 191-198 ◽

Cited By ~ 6

Author(s):

R. M. REEVE

Keyword(s):

Amino Acids ◽

Chlorogenic Acid ◽

Nitrous Acid ◽

Metal Chelate ◽

Ultrastructural Localization ◽

Plant Tissues ◽

Metal Chelation ◽

Copper Chelation ◽

Acid Reaction ◽

Color Reactions

Copper chelation of nitrosotyrosine has been found useful for histochemical localization for tyrosine in thick, fresh sections of large celled plant tissues. The nitrous acid reaction for ortho-dihydroxyphenolics also has been found useful for localization of chlorogenic acid, caffeic acid and dihydroxyphenylalanine in plant tissues. Application of these tests separately to serially adjacent sections demonstrated the distribution of tyrosine and chlorogenic acid in different plant tissues. Tests tube reactions on known substances verified specificity and also demonstrated that the presence of other amino acids and phenolics did not interfere with the positive test for tyrosine. The color reactions are sufficiently intense for stereoscopic microscopy and tested sections may be measured photometrically. Further adaptability of the nitrosotyrosine-metal chelate reaction to procedures for ultrastructural localization is suggested.

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Oxidation of flavonoids by hypochlorous acid: reaction kinetics and antioxidant activity studies

Free Radical Research ◽

10.1080/10715762.2016.1194520 ◽

2016 ◽

Vol 50 (8) ◽

pp. 898-908 ◽

Cited By ~ 6

Author(s):

Justyna Krych-Madej ◽

Katarzyna Stawowska ◽

Lidia Gebicka

Keyword(s):

Antioxidant Activity ◽

Reaction Kinetics ◽

Hypochlorous Acid ◽

Acid Reaction

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Stereoselectivity of montmorillonite in the adsorption and deamination of some amino acids

Clay Minerals ◽

10.1180/claymin.1992.027.1.11 ◽

1992 ◽

Vol 27 (1) ◽

pp. 109-118 ◽

Cited By ~ 30

Author(s):

B. Siffert ◽

A. Naidja

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Reaction Kinetics ◽

Clay Mineral ◽

Room Temperature ◽

Optical Isomers ◽

Racemic Mixtures ◽

Deamination Reaction

AbstractOptical isomers deamination of L- and D-glutamic and aspartic amino acids and of their DL racemic mixtures has been achieved in the presence of Na-montmorillonite at pH = 6 and room temperature. The adsorption curves showed that the enantiomer adsorbed depends on the type of amino acid. Nevertheless, deamination reaction kinetics brought about a stereoselectivity of the clay mineral for the L-isomer and implicitly showed an unquestionable “structural chirality character” of the clay mineral.

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Complexes of molybdenum(V) and molybdenum(IV) with dithiocarbamates derived from α-amino acids. Reaction kinetics in organic solvents

Polyhedron ◽

10.1016/s0277-5387(00)80061-3 ◽

1993 ◽

Vol 12 (23) ◽

pp. 2791-2799 ◽

Cited By ~ 12

Author(s):

Benigno Macias ◽

Julio J. Criado ◽

Maria V. Villa ◽

Licesio J. Rodriguez ◽

Manuel Castillo

Keyword(s):

Amino Acids ◽

Reaction Kinetics ◽

Organic Solvents

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Effect of NaOH mercerisation on the crosslinking of ramie fabric using 1, 2, 3, 4-butanetetracarboxylic acid - reaction kinetics

Journal of the Textile Institute ◽

10.1533/joti.2003.0024 ◽

2005 ◽

Vol 96 (4) ◽

pp. 213-220 ◽

Cited By ~ 2

Author(s):

L. M. Zhou ◽

K. W. Yeung ◽

C. W. M. Yuen ◽

X. Zhou

Keyword(s):

Reaction Kinetics ◽

Acid Reaction ◽

Butanetetracarboxylic Acid

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Kinetics of polymeric substrate (dextrin or peptone) removal by activated sludge: hydrolysis of polymers to monomers is the rate-determining step

Water Science & Technology ◽

10.2166/wst.1997.0443 ◽

1997 ◽

Vol 36 (12) ◽

pp. 159-167 ◽

Cited By ~ 3

Author(s):

Yuu Ubukata

Keyword(s):

Amino Acids ◽

Activated Sludge ◽

Reaction Kinetics ◽

Removal Rate ◽

Order Reaction ◽

First Order Reaction ◽

Municipal Sewage ◽

First Order ◽

Rate Determining Step ◽

Hydrolysis Of

Most of the organic compounds in primary effluent are polymers such as proteins and polysaccharides. However the bacteria present in activated sludge (AS) can only directly take up monomers such as amino acids and glucose which are produced from polymers by hydrolysis. Therefore, it is assumed that the hydrolysis of polymers to monomers by the bacteria is the rate-determining step in polymer removal. In this study, AS was acclimated to dextrin or peptone, and polymers (dextrin or peptone) and monomers (glucose or a mixture of free amino acids) were used as substrates for kinetic tests. The removal of monomers and polymers by the AS followed zero- and pseudo first-order reaction kinetics, respectively. The removal rate of monomers was higher than that of polymers, and the oxygen uptake rate of the AS during monomer removal was higher than that during polymer removal. One of the important differences between the polymers and monomers used in this study is whether glycosidic linkages or peptide bonds exist in the material. It was therefore verified that the hydrolysis of polymers to monomers by AS was the rate-determining step in polymer removal. The removal of polymers apparently followed first-order reaction kinetics at high F/M ratios, but nth-order reaction kinetics at low F/M ratios (n>1), which are commonly used in municipal sewage treatment.

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