Amine Fraction Research Articles

Dopamine 3-O-sulphate, an end product of L-dopa metabolism in Parkinson patients.

PREVIOUS studies from these laboratories1 have shown that L-3,4-dihydroxyphenylalanine (L-dopa) does not undergo sulphoconjugation in vitro in the cytosol sulphating system of rat tissues whereas dopamine very readily yields a mixture of the 3- and 4-O-sulphates. These observations might therefore serve to explain earlier claims2 that sulphoconjugated dopamine constituted a significant proportion of the amine fraction extractable from rat tissues following the administration of 14C-labelled L-dopa and raises the question of the role of sulphoconjugation in dopamine metabolism. In man this may be of significance in L-dopa therapy in the treatment of Parkinson's disease since such conjugates might represent either intermediates or end products of metabolism.

GC-MS identification of bufotenin in urine samples from patients with schizophrenia or infantile autism

Bufotenin was found to be present in urine samples of schizophrenic patients and autistic children, but not of normal controls. The identification was based on TLC of the tertiary amine fraction using a specific o-phthalaldehyde spray, and also on GC. Unambiguous proof of the identity of bufotenin has now been provided by GC-MS analysis of the bufotenin-positive samples through its trimethylsilyl derivative.

The in vivo effect of tropolone on dopamine metabolism and the catechol-O-methyl transferase activity in the striatum of the rat.

The effect of tropolone (100 mg/kg intraperitoneally) on dopamine metabolism in the corpus striatum of rats was studied. The catechol‐O‐methyl transferase (COMT) and monoamine oxidase (MAO) activities were measured as were the concentrations of dopamine (DA) and its metabolites 3‐methoxytyramine (3‐MT), 3,4‐dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA). The amine synthesis was estimated by measuring the accumulation of radioactive metabolites after a constant rate infusion of 14C‐tyrosine in tropolone‐treated and normal rats. In the striatum the tissue concentration of tropolone was reduced by 90% during the first 2.5 hrs period. Tropolone caused a rapid reduction in the methylated metabolites (3‐MT and HVA) while the concentrations of DA and its deaminated metabolite DOPAC were increased. The results from the studies with 14C‐tyrosine suggested a reduced DA synthesis rate. All metabolite concentrations returned to normal within 24 hours. After a 20 minutes infusion with 14C‐tyrosine a higher radioactivity was found in the fractions of the metabolic end products than in the amine fractions. This finding might indicate an initial turnover of DA in order of minutes and may be a reflection of a multicompartment system for amine storage.

The determination of bufotenin in urine of schizophrenic patients and normal controls

One-dimensional chromatography, quantification without previous qualitative identification and without adequate separation of the tertiary amine fraction have all contributed to the confusion in regard to the identification and quantification of bufotenin. We have used for the positive identification of bufotenin: (1) DACA; (2) diazotized o-tolidine, and (3) OPT. Of the three, the last was found to be the most sensitive and specific since it combines in one test the qualitative identification, separation by two-dimensional TLC and the quantitative estimation—all in one step. In our opinion in view of the high sensitivity of this method it should prove a useful screening tool for the identification and quantification of bufotenin in urine samples collected over an 8-hr period. In our experience with urine samples of normals, in contrast to those of chronic schizophrenics and acute schizophrenics, no bufotenin was found in the urine of any normals even when the normals were on an MAO inhibitor and L-cysteine loading. When bufotenin was identified in chronic schizophrenics, the levels were found to be between 3 and 5 μg in 24-hr urine samples. On these standards the negative results found in normals are rated as zero. In the methods we have adopted for the identification of bufotenin, the extraction and separation techniques for N,N-dimethylated compounds—two-dimensional TLC, multiple spray reagents (DACA, diazotized o-tolidine, OPT) and spectrofluorometry when the fluorescence of the OPT products is specific for 5-hydroxytryptaminic compounds— render the identification more conclusive than that by earlier methods. Supportive evidence has been provided by GLC of the amine fractions and their trimethylsilyl derivatives. Work on identification by gas chromatography-mass spectrometry is now in progress. Fisher and Spatz 5 and Sireix and Marini 15 reported fairly high levels of bufotenin even in the urine of normal subjects. If this were the case, the more sensitive OPT method should have given positive results in all urine samples from normals.

The non-protein nitrogen composition of grass silages: II. The changes occurring during the storage of silage

SUMMARYThe nitrogenous composition of the water soluble fraction of maturing grass silage was investigated in detail. Empirical methods of group analysis demonstrated the complete absence of water soluble proteins, and that the major changes, involving the formation of amino acids and volatile amines, were completed within the first 2 months of ensiling. These methods were unable to account for a high proportion of the soluble nitrogen. Changes occurring within the soluble carbohydrate and volatile fatty acid fractions indicated that while secondary fermentations occurred some 8 months after ensiling they did not have any marked influence on the nitrogenous components.A detailed analysis of the individual components of the nitrogenous fraction was undertaken using both conventional methods of ion exchange chromatography and techniques developed especially for this purpose (see Hughes, 1969). Selective degradation of the amino acids liberated by the proteolysis of the grass proteins occurred. The volatile basic nitrogen content was comprised of ammonia. The non-volatile amine fraction, which accounted for a considerable proportion of the soluble nitrogen, was mainly composed of putrescine and cadaverine. There was no free histamine and only low concentrations of bound histamine were found. Evidence suggested that these amines were being further metabolized during the storage of the silage.

VOLATILE AMINES IN THE BREWING PROCESS. THE IDENTIFICATION AND OCCURRENCE OF PYRROLIDINE

Pyrrolidine has been identified as a component of the volatile amine fraction in barley, malt, hops, worts and beer.

Formula omitted] formation of tyrosine from phenylalanine in brain

Labelled phenylalanine was injected into the lateral ventricle of rat brain. After twenty minutes, less than 5% of the C 14 could be found in whole brain extract. Distributions of the radioactivity in extracts from the brain stem and from the cerebellum were: 4–8% in the acidic metabolites, 49–78% in the neutral compounds and less than 1% in the amine fraction. The neutral fraction contained a small but significant quantity of labelled tyrosine. Radioactivity was detected in NE isolated from brain stem. Pretreatment of the rats with p-CPA did not block the formation of radioactive tyrosine.

Principal Aliphatic Secondary Amines of Burley Tobacco

AbstractQuantity and distribution of the principal aliphatic secondary amines - dimethylamine, methylethylamine, diethylamine, and methylpropylamine - varied within plant tissue and among Nicotiana spp. In Burley tobacco the stem tissue had the highest content of these amines and the leaf midrib the lowest. Leaf lamina, roots and seed were intermediate in amine content. Among Nicotiana spp. there was considerable difference in total amine content as well as among the ratios of the amine fractions measured. Amine content of tissue was positively correlated with nitrogen content of tissue and was altered by the drying process of tissue prior to analysis. The amines were not present as free amines or salts but were detected only following steam distillation from a basic medium

N-Méthylations de l'aniline par Mycobacterium tuberculosis

N-methylations of aniline by Mycobacterium tuberculosis 1. 1. Following reports by Sloane et al. 1–5 on the enzymatic hydroxymethylation of the aromatic nucleus by Mycobacterium tuberculosis ATCC 607 or guinea-pig liver microsomes, the possible donors of the “C-1” moiety were investigated. 2. 2. Incubation of aniline with whole cells of M. tuberculosis ATCC 607 in the presence of [ 14C]formate resulted in a very low incorporation of activity, compared with that form [ Me- 14C]methionine, into the aromatic amine fraction isolated. 3. 3. Methionine was therefore considered as the most likely C-1 donor, and the products arising from incubation of aniline with M. tuberculosis in the presence of [ Me- 14C]methionine were examined. No evidence was found for the formation of p-aminobenzyl alcohol; the major radioactive product proved to be N-methylaniline. This compound, together with a small proportion of N-dimethylaniline, was also isolated from similar experiments with cell-free extracts. The formation of N-dimethylaniline was confirmed by incubation of N-methylaniline itself. 4. 4. Subsequently, [ 14C]aniline was incubated with whole cells of M. tuberculosis, according to the method of Sloane and Untch 1. Radioactivity was not completely lost from derivatives prepared from carrier p-aminobenzyl alcohol, but control experiments, without cells and with autoclaved cells, gave identical results. It is concluded that, in this case, enzymic formation of p-aminobenzyl alcohol does not occur.

Ultrasonic absorption properties of solutions. Part 8.?(i) Diethylamine + water mixtures (ii) ultrasonic absorption and miscibility curves for some mixtures of water + t-butyl alcohol + t-amyl alcohol

(i)[Blandamer, Hidden and Symons] The ultrasonic absorption properties are reported for mixtures of diethylamine + water, methyl alcohol, and t-butyl alcohol. Mixtures of diethylamine + water show intense excess abosorptions and this has been measured at 0 and 25° and over the frequency range 1.5–230 MHz. The variation of α/f2 with frequency for mixtures where the mol fraction of amine is between 0.05 and 0.25 is analyzed using two relaxation frequencies. The behaviour is compared with ultrasonic data for water + monohydric alcohol mixtures. (ii)[Blandamer, Hidden and Treloar] The mutual solubility curve for mixtures of water +(40 mol % t-amyl alcohol + 60 mol % t-butyl alcohol) has a lower critical solution temperature and closely resembles the curve for the ultrasonic absorption against mol fraction of water. The ultrasonic absorption αf2 at a fixed frequency f and composition decreases initially with increase in temperature but then increases as the critical temperature is approached. The absorption for a given mixture depends on f–5/4.

On the evaluation of the pregnancy test by the occurrence of polyamine in the bovine blood plasma

Morgantini's pregnacy diagnosis test, the colour reaction of blood plasma produced by heating in the presence of cupric carbonate, was performed with bovine blood plasma in various conditions. But the availability of the test resulted in definitely negative since results of the reaction happened to be almost all positive regardless to the pregnancy or not.Next, spermine, which regarded as the reactive substance in the preceding colour reaction, was detected together with other amines in blood plasma by paper-chromatography to know whether the amines appeared specifically in pregnant plasma. Volatile amine fraction was prepared from the TCA soluble fraction by the vapour distillation with Kjeldahle apparatus. The findings by the paper-chromatography showed that two spots, corresponded to spermine or spermidine and putrescine, also existed independent of the animal condition either pregnancy or lactation. Therefore, the authors completely failed to ascertain the Morgantini's investigation as the pregnancy diagnosis test based on either the colour reaction with cupric carbonate or the detection of spermine with paper-chromatography in bovine plasma. The occurrence of polyamines in the bovine blood plasma and the pregnancy tests which seemed to be related to this test was briefly discussed.