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At least 145 records · Page 8Linked to original sources
PubMed1993

Metabolism of biogenic monoamines in the ciliated protozoan, Tetrahymena pyriformis.

1. The three-dimensional HPLC system was used to detect the presence and determine the levels of biogenic monoamines, including precursor amino acids and metabolites, simultaneously in an extract of the ciliated protozoan, Tetrahymena pyriformis. 2. Representative biogenic monoamines, such as dopamine (DA), 5-hydroxytryptamine (5-HT), epinephrine (E) and kynurenine (KYN) were found to be synthesized in Tetrahymena and released into the growth medium. 3. The following metabolic pathways were suggested to be operative: (L-DOPA)-DA-(Epinine)-E-dihydroxyphenylethyleneglycol (DOPEG)-vanillylmandelic acid (VMA) and tyrosine-4 (TYR-4)-tyramine (TYRA)-hydroxyphenylacetic acid-4 (HPAC-4) in the case of catecholamines, and tryptophan (TRP)-5-HT and TRP-KYN-xanthurenic acid (XA) in the case of indolalkylamines. 4. As judged from the released metabolites, systems for generation of biogenic monoamines in Tetrahymena seem to be active during the logarithmic phase of its growth.

Animals↗
PubMed2004

New solvent systems for thin-layer chromatographic determination of nine biogenic amines in fish and squid.

Different solvent systems were evaluated for their ability to separate biogenic amines by thin-layer chromatography (TLC). Dansyl derivatives of agmatine, putrescine, tryptamine, cadaverine, spermidine, histamine, spermine, tyramine and beta-phenylethylamine were separated using the solvent system chloroform-diethyl ether-triethylamine (6:4:1), followed by chloroform-triethylamine (6:1). After separation dansyl amines were quantified by fluorescence densitometry at 330 nm. Correlation coefficients of linear regressions were higher than 0.99 for all amines, except for agmatine (0.976). Detection limits were 10ng for tryptamine, tyramine, histamine and beta-phenylethylamine, and 5 ng for the other amines. The overall repeatability of the chromatography was 1.82% when including agmatine and barely 1.02% for the other amines. The accuracy ranged from 105.97% (agmatine) to 49.92% (tryptamine). This thin-layer chromatography method was found to be an effective and precise analytical procedure to separate and determine biogenic amines. Its main advantages compared to previous procedures are that it uses less harmful solvent (diethyl ether instead of benzene) and can separate a larger group of biogenic amines.

Animals↗
PubMed2005

Determination of biogenic amines in fresh and processed meat by suppressed ion chromatography-mass spectrometry using a cation-exchange column.

A new method for simultaneous determination of underivatized biogenic amines based on the separation by cation-exchange chromatography and suppressed conductivity coupled with mass spectrometry detection has been developed. The method has been applied to the analysis of cadaverine, putrescine, histamine, agmatine, phenethylamine and spermidine in processed meat products. The amines were extracted from muscle tissue with methanesulfonic acid without any additional derivative step or sample clean-up. Biogenic amines were separated by the IonPac CS17 column, a cation-exchange column used with gradient elution, and detection was done by suppressed conductivity and mass spectrometry. Tyramine was simultaneously analysed by using a spectrophotometer (275 nm) before the suppressed conductivity detection. Linearity of response was obtained in the range 0.25-25 microg mL(-1). The detection limits ranged from 23 microg L(-1) for putrescine to 155 microg L(-1) for spermidine (suppressed conductivity) and from 9 microg L(-1) for agmatine to 34 microg L(-1) for spermidine (MS). Average recoveries from meat samples ranged from 85 to 97% and coefficients of variation ranged from 4.5 to 9.7%. The analysis of biogenic amines in fresh and processed meats (dry-cured, cooked and fermented products) can be used as a quality marker of raw material and for studying the relationship between their changes and the fermentation process involved in dry sausage ripening.

Animals↗
PubMed2005

Determination of biogenic amines by capillary zone electrophoresis with conductometric detection.

A capillary zone electrophoresis (CZE) method with conductometric detection of biogenic amines (cadaverine, putrescine, agmatine, histamine, tryptamine and tyramine) is described. The optimised background electrolyte was the following: 15 mM histidine + 5 mM adipic acid + 1.5 mM sulphuric acid + 0.1 mM ethylenediaminotetraacetic acid + 0.1% hydroxyethylcellulose + 50% methanol. A clear separation of six biogenic amines from other components of acidic sample extract was achieved within 10 min. Method characteristics, i.e., linearity (0-100 micromol/ml), accuracy (recovery 86-107%), intra-assay repeatability (2-4%), and detection limit (2-5 micromol/l) were evaluated. Low laboriousness, sufficient sensitivity, speed of analysis, and low running cost are important attributes of this method. The developed method was successfully applied on the determination of biogenic amines in selected food samples.

Beer↗
PubMed2005

An improved method for the separation and detection of biogenic amines in adult Drosophila brain extracts by high performance liquid chromatography.

Biogenic amines are critically important neuromodulators in both vertebrates and invertebrates. Quantification of these amines can be difficult, particularly in neural extracts of Drosophila melanogaster that contain interfering electroactive compounds. We have developed a method for the reliable separation and quantification of the biogenic amines dopamine, serotonin, tyramine, and octopamine in Drosophila brain extracts using high performance liquid chromatography with electrochemical detection. Our method obviates the need for complex preparatory procedures or instrumentation, and can reproducibly detect picogram quantities of these amines. By optimizing the composition of the mobile phase and the electrode potential, and by examining common complications in the analysis of biological samples, we have developed a reliable technique for monitoring levels of biogenic amines in the Drosophila brain.

Animals↗
PubMed2004

Micellar liquid chromatography determination of some biogenic amines with electrochemical detection.

A simple and reliable liquid chromatographic procedure is successfully applied to the simultaneous determination of the biogenic amines, dopamine, serotonin, their metabolites (homovalinic acid (HVA) and hydroxyindoleacetic acid (HIAA)) as well as tyramine in serum samples. After an optimization procedure using a C18 column, the mobile phase selected was 0.15 M sodium dodecyl sulfate buffered at pH 3, in which the serum samples were directly injected and the analysis time for the five substances was less than 12 min. The use of electrochemical (ED) and ultraviolet (UV) detection was compared. The limits of detection of the biogenic amines studied were drastically improved using ED detection. Repeatability and intermediate precision were tested at three different concentrations and the relative standard deviations were below 1.5% for most assays. Finally, the method was successfully applied to the determination of biogenic amines in serum samples.

Biogenic Amines↗
PubMed2003

Evaluation of the nocturnal levels of urinary biogenic amines in men exposed overnight to 50-Hz magnetic field.

The aim of this study was to determine whether exposure to magnetic fields might affect human health and to look for possible effects of acute exposure (9 hours) to 50-Hz magnetic fields (10 microT) on the urinary concentration of biogenic amines. Thirty-two young men (20-30 years old) were divided into two groups (sham-exposed and exposed group) of 12 to 16 subjects each. All subjects participated in two 24-hour experiments to evaluate the effects of both continuous and intermittent exposure to magnetic fields. The subjects were exposed to the magnetic field from 2300 to 0800, while lying down. Total urine (from 2300 to 0800) was collected at 0800. The results (expressed as a ratio of biogenic amine excretion to creatinine excretion (nmol/mmol)) did not differ significantly between sham-exposed and exposed men for any of the parameters measured: adrenaline, noradrenaline, dopamine, dihydroxyphenylalanine, 3,4-dihydroxyphenylacetic acid, homovanillic acid and 5-hydroxyindoleacetic acid. These results suggest that nocturnal exposure to either continuous or intermittent 50-Hz magnetic fields of 10 microT does not affect, at least under our experimental conditions, the nocturnal excretion of biogenic amines in healthy young men.

Adult↗
PubMed2002

In vivo effects of high phenylalanine blood levels on Na+,K+-ATPase, Mg2+-ATPase activities and biogenic amine concentrations in phenylketonuria.

OBJECTIVE: To evaluate the activities of Na+,K+-ATPase and Mg2+-ATPase in erythrocyte membranes from phenylketonuric (PKU) patients and to correlate the enzyme activities with their blood phenylalanine (Phe) levels, biogenic amines as well as with their precursors tyrosine (Tyr) and tryptophan (Try). DESIGN AND METHODS: Twenty three PKU patients were divided into group A (n = 12) on a restricted diet (Phe 1.57 +/- 0.52 mg/dL or 0.10 +/- 0.03 mM) and group B (n = 11) on a "loose" diet (Phe 24.45 +/- 1.50 mg/dL or 1.72 +/- 0.09 mM). The enzyme activities were measured spectrophotometrically, the amino acids with an automatic amino analyser and the biogenic amines with HPLC methods. RESULTS: In group B, plasma amino acids (Tyr, Try), their biogenic amines [adrenaline (A), noradrenaline (NA), dopamine (DA) and serotonin (5HT)], (Na+,K+)-ATPase and Mg2+-ATPase activities were found remarkably decreased (p < 0.001). CONCLUSIONS: High Phe and/or low NA, DA, 5HT plasma levels may indirectly inhibit the erythrocyte membrane Na+,K+-ATPase and Mg2+-ATPase in PKU patients. The observed enzyme inhibitions could be a very informative peripheral marker as regards the neurotoxic Phe brain effects.

Amino Acids, Aromatic↗
PubMed2003

Determination of biogenic amines by capillary electrophoresis with pulsed amperometric detection.

The biogenic amines, putrescine, cadaverine, spermidine and spermine were separated and quantified by capillary electrophoresis with pulsed amperometric detection. Detection potential of the pulsed amperometric detection was optimized as 0.6 V. Optimal separation of the biogenic amines was achieved using a separation buffer of 30 mM citrate at pH 3.5, while keeping the buffer in the detection cell as 20 mM NaOH. Using these conditions, the four biogenic amines were baseline separated. Extrapolated limits of detection for putrescine, cadaverine, spermidine and spermine were 400, 200, 100 and 400 nM for the standard mixture (polyamines dissolved in running buffer), respectively. These are lower than ultraviolet detection and comparable or even lower than laser-induced fluorescence detection results as reported in the literature. The number of theoretical plates was maintained at the 10(5) level, which is absolutely higher than any reported method. When applying capillary electrophoresis-pulsed amperometric detection to milk analysis, only spermidine was found in amounts varying between 0.1 and 0.5 mg/kg.

Animals↗
PubMed1998

Direct determination of biogenic amines in wine by integrating continuous flow clean-up and capillary electrophoresis with indirect UV detection.

A flow-injection manifold for automating the determination of biogenic amines in wine using capillary electrophoresis (CE) with indirect UV detection was developed. The ensuing method involves clean-up and solid-phase extraction (SPE) of the target analytes in the sample. Various treatments involving different SPE minicolumns were tested and compared. The C18 minicolumn was chosen to concentrate the amines following addition of ammonium chloride and ammonium hydroxide as buffer to neutralize them. Additions of amine standards were used to determine recoveries. Biogenic amines can be separated and detected after SPE with limits of detection in the range 0.05-0.1 microgram ml-1 by using 4 mM copper(II) sulphate, formic acid and 18-crown-6 as running buffer. All the amines studied are eluted within 15 min under the optimum conditions established. The overall process was successfully used to identify biogenic amines in various types of wine from different Spanish regions.

Biogenic Amines↗
PubMed1999

Determination of biogenic amines by capillary electrophoresis.

A method for determining biogenic amines in food using micellar electrokinetic capillary chromatography has been developed. Derivatization of the amines was performed with AccQ (6-aminoquinolyl-N-hydroxysuccinimidyl carbamate; Waters, Milford, MA, USA) reagent. The influence of buffer composition on the separation (including pH, SDS concentration and various additives) was investigated. The separation of seven biogenic amines (histamine, tyramine, tryptamine, spermine, spermidine, cadaverine and putrescine) could be achieved within 25-30 min with good repeatability. The biogenic amine profiles in three different food samples (wine, salami and chive) were determined and quantitated.

Acetonitriles↗
PubMed2003

Screening of biogenic amine production by lactic acid bacteria isolated from grape must and wine.

The potential to produce the biogenic amines tyramine, histamine and putrescine, was investigated for lactic acid bacteria (LAB) of various origin, including commercial malolactic starter cultures, type strains and 78 strains isolated from Spanish grape must and wine. The presence of biogenic amines in a decarboxylase synthetic broth was determined by reverse-phase high performance liquid chromatography (RP-HPLC). Tyramine was the main amine formed by the LAB strains investigated. Leuconostoc strains were the most intensive tyramine formers. No potential to form biogenic amines was observed in Oenococcus oeni strains. Two strains of Latobacillus buchneri were associated with putrescine formation. None of the lactic acid bacteria produced histamine. According to these in vitro results, the commercial starter bacteria analyzed did not produce histamine, tyramine and putrescine.

Biogenic Amines↗
PubMed1989

Simultaneous determination of biogenic amines, their precursors and metabolites in a single brain of the cricket using high-performance liquid chromatography with amperometric detection.

An analytical procedure has been developed for the simultaneous determination of biogenic amines, their precursors and metabolites by high-performance liquid chromatography with amperometric electrochemical detection. Following careful adjustment of various factors involved in the separation efficiency, reversed-phase chromatography with an ion-pairing technique gave simultaneous separation of nineteen biogenic amines and related substances. Peak identification was confirmed by comparison with hydrodynamic voltammograms. The method was sensitive enough to detect each substance in the picomole range. The procedure was applied to quantitate the amount of biogenic amines in a single brain of the cricket.

Animals↗
PubMed2004

Evaluation of biogenic amines and microbial counts throughout the ripening of goat cheeses from pasteurized and raw milk.

The effect of the hygienic quality of milk on changes in microbial counts and biogenic amine content was evaluated during ripening of goat cheeses manufactured from pasteurized and raw milks at 1, 14, 30, 60 and 90 d. The original milk, rennet, curd and whey were also included in the study. The pH, salt content and extent of proteolysis in the cheese were also evaluated. Spermidine and spermine were the main amines in raw milk, while they were minor amines in cheeses. Other amines increased markedly during ripening, tyramine being the main amine in cheese made from raw milk and cadaverine and putrescine in those produced from pasteurized milk. Enterobacteriaceae counts decreased during ripening whereas those of lactic acid bacteria increased, especially lactobacilli and enterococci. Cheese made from raw milk showed higher microbial counts during ripening than those made from pasteurized milk, especially for Enterobacteriaceae and enterococci, counts being 2 or 3 log units higher. Raw milk cheese showed remarkably higher biogenic amines compared with pasteurized milk cheeses. Therefore, pasteurization of milk causes a decrease in final biogenic amine content of cheese as a result of the reduction of its microbial counts.

Animals↗
PubMed2003

Principal component and linear discriminant analyses of free amino acids and biogenic amines in hungarian wines.

Principal component analysis (PCA) and linear discriminant analysis (LDA) were used to classify 187 Hungarian white and red wines according to wine-making technology, geographic origin (wine-making region), grape variety, and year of vintage based on free amino acid and biogenic amine contents. Determination of free amino acids and biogenic amines was accomplished by ion-exchange chromatography. Six principal components accounted for >77% of the total variance in the data. The plots of component loadings showed significant groupings of free amino acids and biogenic amines. The component scores grouped according to wines made by different wine-making technologies. Using LDA the variables with a major discriminant capacity were determined. Almost complete classification (94.7%) was achieved concerning both white and red wines and wines made by different wine-making technologies. The results of differentiation between white wines according to geographic origin, grape variety, and year of vintage were 70.8, 62.4, and 73.5%, respectively. The same numbers for red wines according to geographic origin, grape variety, and year of vintage were 64.9, 71.6, and 82.4%, respectively.

Amino Acids↗
PubMed2004

Free and conjugated biogenic amines in green and roasted coffee beans.

This work reports the composition of arabica and robusta coffees in terms of biogenic amines. The analyses were conducted before and after acid hydrolysis with the aim of the determining both free and conjugated forms in green and roasted coffee beans. The amines (putrescine, cadaverine, serotonin, tyramine, spermidine, and spermine) were determined by reverse-phase high-performance liquid chromatography (RP-HPLC) after derivatization with dansyl chloride. Multivariate analyses were applied in order to evaluate the possible use of these amines as chemical descriptors for arabica and robusta coffees. It was found that putrescine, the main biogenic amine present in the green beans, could be used in the discrimination of the referred species. There is also some evidence that these compounds can be used for discrimination between green coffees subjected to different postharvest processes and that tyramine can be considered a chemical marker for Angolan robustas. The variations in biogenic amine levels after roasts is also discussed, but the statistical significance for species discrimination is reduced.

Analysis of Variance↗
PubMed2006

Biogenic amine formation and nitrite reactions in meat batter as affected by high-pressure processing and chilled storage.

Changes in biogenic amine formation and nitrite depletion in meat batters as affected by pressure-temperature combinations (300 MPa/30 min/7, 20, and 40 degrees C), cooking process (70 degrees C/30 min), and storage (54 days/2 degrees C) were studied. Changes in residual nitrite concentration in raw meat batters were conditioned by the temperature and not by the pressure applied. Cooking process decreased (P < 0.05) the residual nitrite concentration in all samples. High-pressure processing and cooking treatment increased (P < 0.05) the nitrate content. Whereas protein-bound nitrite concentration decreased with pressure processing, no effect was observed with the heating process of meat batters. High-pressure processing conditions had no effect on the rate of residual nitrite loss throughout the storage. The application of high pressure decreased (P < 0.05) the concentration of some biogenic amines (tyramine, agmatine, and spermine). Irrespective of the high processing conditions, generally, throughout storage biogenic amine levels did not change or increased, although quantitatively this effect was not very important.

Animals↗
PubMed2000

Multiple compound quality index for cold-smoked salmon (Salmo salar) developed by multivariate regression of biogenic amines and pH.

Production of biogenic amines during chill storage of 12 lots of cold-smoked salmon was studied. These data allowed for a multiple compound quality index to be developed by multivariate regression (partial least square regression). The quality index was based on concentrations of cadaverine, histamine, putrescine, and tyramine and pH and showed good correlation with sensory assessments. Biogenic amines were indicators of spoilage rather than casual agents of spoilage off-flavors. Four different biogenic amine profiles were found at the time of spoilage in cold-smoked salmon. These were the results of differences in the spoilage microflora. Histamine was detected above regulatory limits but below toxic levels. Measurements of salt and dry matter for calculation of water phase salt could be substituted by rapid water activity measurements.

Animals↗