Quantitative aspects of urinary indolo-3-acetic acid and 5-hydroxyindole-3-acetic acid excretion

Facile Preparation of Deuterium-Labeled Standards of Indole-3-Acetic Acid (IAA) and Its Metabolites to Quantitatively Analyze the Disposition of Exogenous IAA inArabidopsis thaliana

[2',2'-(2)H(2)]-indole-3-acetic acid ([2',2'-(2)H(2)]IAA) was prepared in an easy and efficient manner involving base-catalyzed hydrogen/deuterium exchange. 1-O-([2',2'-(2)H(2)]-indole-3-acetyl)-beta-D-glucopyranose, [2',2'-(2)H(2)]-2-oxoindole-3-acetic acid, and 1-O-([2',2'-(2)H(2)]-2-oxoindole-3-acetyl)-beta-D-glucopyranose were also successfully synthesized from deuterated IAA, and effectively utilized as internal standards in the quantitative analysis of IAA and its metabolites in Arabidopsis thaliana by using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). The use of this technique shows that these metabolites were accumulated in the roots of Arabidopsis seedlings. Dynamic changes in the metabolites of IAA were observed in response to exogenous IAA, revealing that each metabolic action was regulated differently to contribute to the IAA homeostasis in Arabidopsis.

Biogenic amines and their metabolites in body fluids of normal, psychiatric and neurological subjects

The biogenic monoamines and their metabolites have been isolated, identified and quantified in human body fluids over the past forty years using a wide variety of chromatographic separation and detection techniques. This review summarizes the results of those studies on normal, psychiatric and neurological subjects. Tables of normal values and the methods used to obtain them should prove to be useful as a reference source for benchmark amine and metabolite concentrations and for successful analytical procedures for their chromatographic separation, detection and quantification. Summaries of the often contradictory results of the application of these methods to psychiatric and neurological problems are presented and may assist in the assessment of the validity of the results of experiments in this field. Finally, the individual, environmental and the methodological factors affecting the concentrations of the amines and their metabolites are discussed.

Growth regulators, Rhizobium and nodulation in peas : Indole-3-acetic acid from the culture medium of nodulating and non-nodulating strains of R. leguminosarum

Indole-3-acetic acid (IAA) has been identified in the culture medium of nodulating and non-nodulating strains of Rhizobium lebuminosarum by gas chromatography-mass spectrometry. The levels of IAA produced by the different strains have been quantified using multiple ion monitoring and a deuterated internal standard. Indole-3-acetic acid is produced in the absence of exogenous tryptophan in all strains but its level is greatly stimulated by applied tryptophan. No correlation has been established between the ability to nodulate peas and the ability to produce IAA.

Free tryptophan and indole-3-acetic acid levels in the leaves and vascular pathways of Ricinus communis L

Levels of free tryptophan in the leaves, phloem and xylem saps of Ricinus communis L. were determined by colorimetric assay. Values of 0.38 μg ml(-1) in root pressure sap and 96.0 μg ml(-1) in phloem sap were recorded. Tryptophan levels were highest in mature and senescing leaves. Levels of indoleacetic acid (IAA) in the phloem sap and leaves were determined by gas chromatography-mass spectrometry using a deuterated internal standard. A mean value of 13.0 ng ml(-1) was recorded in phloem sap. The distribution in the leaves showed an inverse relationship to that of tryptophan, being highest in young leaves.

Determinations of indole-3-acetic acid in xylem sap of Ricinus communis L. using mass fragmentography

Mass fragmentography employing a deuterated internal standard was used to make quantitative analyses of indole-3-acetic acid in xylem sap collected from Ricinus communis L. When contamination of the sap by microorganisms was reduced by frequent collection, levels of IAA were found to be less than 0.5 ng ml(-1). It is therefore proposed that the transpiration stream does not play a significant role in the transport of IAA within the plant.

A selected bibliography of biomedical and environmental applications of stable isotopes. I--Deuterium 1971-1976

A compilation of selected references to the use of deuterium in biochemical, pharmacological, clinical and environmental applications for the period 1971-1976 is presented. As a further aid, author and subject indices have been compiled.