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PubMed2003

Determination of biogenic amines as dansyl derivatives in alcoholic beverages by high-performance liquid chromatography with fluorimetric detection and characterization of the dansylated amines by liquid chromatography-atmospheric pressure chemical ionization mass spectrometry.

A sensitive high-performance liquid chromatographic method for the simultaneous determination of 11 biogenic amines has been developed. The method involves addition of an internal standard (1,7-diaminoheptane), pre-column dansylation of the amines and subsequent solid-phase extraction of the derivatives through C18 cartridges. The dansylamides were separated on an Inertsil ODS-3 column (250 x 4 mm I.D., 5 microm) using a 35-min gradient elution with a binary system of acetonitrile-water, a flow-rate of 1 ml min(-1) and fluorescence detection at excitation and emission wavelengths of 320 and 523 nm, respectively. The identity of the dansyl derivatives was confirmed by liquid chromatography-atmospheric pressure chemical ionization mass spectrometry. Linearity of derivatization was obtained for concentrations ranging from 0.008 to 40.0 mg l(-1). The within- and between-day relative standard deviations ranged from 0.2 to 7.6% and 0.3 to 8.6%, respectively. The overall process was successfully applied to identify and quantify biogenic amines in white-, red- and Retsina Greek wines and Greek beers, after treatment with polyvinylpyrrolidone.

Alcoholic Beverages↗
PubMed2003

Separation of biogenic amines by micellar electrokinetic chromatography with on-line chemiluminescence detection.

A method of on-line chemiluminescence detection with capillary electrophoresis for biogenic amines (diaminopropane, putrescine, cadaverine and diaminohexane) labeled with N-(4-aminobutyl)-N-ethylisoluminol is reported for the first time. Two separation modes, capillary zone electrophoresis and micellar electrokinetic chromatography (MEKC), were studied. The results show that excellent resolution was achieved in MEKC. Parameters affecting separation process and chemiluminescence detection have been examined in detail. Under the optimum conditions, the baseline separation of four amines was obtained within 7.5 min. The detection limits (S/N=3) of diaminopropane, putrescine, cadaverine and diaminohexane are 3.5 x 10(-8), 3.5 x 10(-8), 3.9 x 10(-8) and 1.2 x 10(-7) M, respectively. The method was applied to the analysis of biogenic amines in lake water.

Biogenic Amines↗
PubMed2003

Determination of biogenic amines as their benzoyl derivatives after cloud point extraction with micellar liquid chromatographic separation.

The advantages of micellar cloud point extraction combined with a surfactant-assisted separation in a HPLC system are presented as a method for the effective separation and determination of nine biogenic amines in fish substrates. Benzoyl derivatives of the amines are extracted inside the micelles of a non-ionic surfactant, Triton X-114, and separated with gradient elution micellar liquid chromatography. Quantification was performed by measuring the UV absorbance of the benzene ring at 254 nm. Detection limits of the nine biogenic amines were in the vicinity of 0.01 mg l(-1) which are approximately 10 times lower than those of the conventional method (HPLC-UV) and 100 times lower than those of micellar electrokinetic capillary chromatography. The correlation coefficients of determinations were 0.9911-0.9996. The method was applied for the determination of putrescine, cadaverine, agmatine, tyramine, tryptamine, phenylethylamine, spermine, spermidine and histamine in trout samples. Recovery of the proposed method ranged from 95 to 103.5%.

Animals↗
PubMed1999

Condensation nucleation light scattering detection for biogenic amines separated by ion-exchange chromatography.

A sensitive method of analysis for biogenic amines, putrescine, cadaverine, histamine and an amino acid precursor, histidine is described herein using ion-exchange chromatography and condensation nucleation light scattering detection. The method was successfully used for the analysis of biogenic amines in fish samples. The method offers a number of advantages: fast elution of analytes with no need for mobile phase conductivity suppression, no derivatization and no electrochemical activity for the analyte's detection. The 3 sigma detection limits for these compounds were found to range from 8 to 20 ng/ml.

Animals↗
PubMed2000

Analysis of biogenic amines by solid-phase microextraction and high-performance liquid chromatography with electrochemical detection.

We investigated the new solid-phase microextraction method by high-performance liquid chromatography with electrochemical detection for the analysis of biogenic amines. The Carbowax-Templated Resin 50 microm (purple) fibre coating offers good performances for dopamine and serotonin separation, i.e., good selectivity and high sensibility (0.1 microg l(-1)). We also tested this fibre for biogenic amines quantification of rat striatum. The coating seems to be selective towards the amines and has low affinity for the metabolites, allowing a good separation and preventing drawbacks from the biological matrix. These first results obtained using this original separation method offer large perspectives of application to many biological samples.

Animals↗
PubMed1976

Urinary biogenic amines in idiopathic apnea of prematurity.

Urinary biogenic amines were measured in 22 preterm infants of less than 36 weeks' gestational age. Fifteen of these infants had idiopathic apnea. Although levels of urinary dopa were not significantly different, dopamine, norepinephrine and epinephrine were all significantly lower in the infants with apena. It is proposed that apnea of prematurity may be related to an immaturity of catecholamine-producing pathways, leading to inadequate physiologic responses to hypoxia, with resulting accentuation of central respiratory depression. Alternatively, urinary biogenic amines may be a reflection of some unrelated process occurring elsewhere in the body or a depletion of catechol stores resulting from the apnea itself.

Apnea↗
PubMed1986

Changes in plasma corticosterone and cerebral biogenic amines and their catabolites during training and testing of mice in passive avoidance behavior.

Concentrations of cerebral biogenic amines and their catabolites, and of plasma corticosterone were determined 10 min after training and testing of passive avoidance behavior in mice. Training and testing of mice that had acquired the task well resulted in statistically significant increases of plasma corticosterone, of the DOPAC:DA ratio [an index of dopamine (DA) metabolism] in prefrontal cortex, and of MHPG:NE ratios [an index of norepinephrine (NE) metabolism] in hypothalamus and brain stem. There were also decreases of NE in hypothalamus and brain stem, and an increase of 5-HIAA:5-HT [an index of serotonin (5-HT) metabolism] and of tryptophan in brain stem. Some of these changes also occurred in mice merely exposed to the apparatus but not trained. Plasma corticosterone concentrations were significantly higher in mice that performed the task well compared to those that did not, and there were significant correlations between this measure and the avoidance performance. Although there was only one statistically significant correlation between a cerebral metabolite and the avoidance performance (a decrease in hypothalamic NE), there were indications of relationships between cerebral biogenic amine metabolism and the performance. The patterns of neurochemical and endocrine changes closely resemble those previously observed in response to various stressors. Thus, the changes could reflect stress responses, which may or may not be related directly to the performance of the avoidance task.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1998

Effects of ventrolateral medullary NMDA-receptor antagonism on biogenic amines and pressor response to muscle contraction.

Effects of D(-)2-amino-7-phosphonohepatanoic acid (AP-7), an N-methyl-D-aspartic acid (NMDA) receptor antagonist, administered into rostral ventrolateral medulla (RVLM) on changes in mean arterial pressure (MAP), heart rate (HR), extracellular levels of serotonin (5-HT), dopamine (DA), and norepinephrine (NE) during static muscle contraction were investigated in anesthetized rats. Tibial nerve stimulation-evoked muscle contraction increased MAP and HR by 25+/-3 mmHg and 29+/-4 bpm, respectively. Microdialysis of AP-7 (1 microM) into the RVLM for 30 min attenuated the contraction-evoked cardiovascular responses with similar developed muscle tensions, without baseline HR or blood pressure changes. Administration of AP-7 into the caudal ventrolateral medulla had no effect on MAP or HR responses during contraction. Muscle contraction increased extracellular 5-HT in the RVLM by 144+/-35%, DA by 104+/-15% and NE by 62+/-12%. Perfusion of AP-7 for 30 min into the RVLM attenuated contraction-evoked increases in monoamines, concomitant to attenuating cardiovascular responses. Results demonstrate that NMDA-receptor blockade within the RVLM, but not the CVLM, inhibits cardiovascular responses during muscle contraction. Furthermore, NMDA receptor antagonism within the RVLM results in a decrease of biogenic amine release during muscle contraction, suggesting that extracellular biogenic amine concentrations are modulated by NMDA receptors.

2-Amino-5-phosphonovalerate↗
PubMed2001

Evidence for proteolytic activity and biogenic amines production in Lactobacillus curvatus and L. homohiochii.

After screening 372 strains of Lactobacillus spp. isolated from a Portuguese traditional dry fermented sausage, two Lactobacillus strains, a Lactobacillus homohiochii and a L. curvatus were selected, because they were positive for tyrosine and ornithine decarboxylase activities. Evidence for extracellular proteolytic activity was also demonstrated for the two Lactobacillus strains, with some strain variation in terms of specific activities towards different substrates. Proteolytic activity was shown to be maximal in the early exponential growth. This proteolytic activity was higher when cells were grown in a peptide-rich medium such as MRS, when compared to skim milk. A study using several protease inhibitors showed that this activity is associated with metalloproteases in the case of the L. curvatus strain, but for L. homohiochii besides metalloproteases, serine-type proteases are also involved. In proteinaceous substrates, like dry fermented sausages, the formation of the biogenic amines putrescine and tyramine cannot be excluded when ongoing proteolysis leads to their precursors, as it is the case in the presence of these proteolytic Lactobacillus strains. Their ability to produce biogenic amines may be used as an index of microbial quality of the fermented meat product.

Animals↗
PubMed1999

Effect of proteolytic starter cultures of Staphylococcus spp. on biogenic amine formation during the ripening of dry fermented sausages.

The effect of proteolytic starter cultures of Staphylococcus carnosus and Staphylococcus xylosus on biogenic amine production was examined during the fermentation process of dry sausages. Microbial counts (lactic acid bacteria, Micrococcaceae and Enterobactenaceae), pH, moisture and proteolysis-related parameters were also studied. The polyamines spermine and spermidine were the main amines found in the raw material and they only showed slight fluctuations during the fermentation. The four elaborated batches presented a significant (P < 0.001) formation of tyramine and putrescine. The main rate of amine production was during the first three days, when a sharp pH decrease and the development of lactic acid bacteria occurred. Sausages fermented with starters had lower amounts of tyramine than naturally fermented sausages (control), but differences in the Micrococcaceae counts were only significant during the first week of the ripening process. A slight formation of diaminopropane, cadaverine, agmatine, tryptamine and phenylethylamine was observed. The amounts of histamine were constant and remained below 0.5 mg/kg of dry matter, while serotonin, octopamine and dopamine were not detected. The sausages with Staphylococcus as starter culture showed strong proteolysis that was correlated with higher pH values than those of the control sausages. However, no positive correlation was found between the proteolysis index and biogenic amine production. Since proteolysis was stronger during the second half of the ripening process, the release of free amino acids as amine precursors occurred later than the early amine production.

Animals↗
PubMed1999

Effect of added proteinases and level of starter culture on the formation of biogenic amines in raw milk Manchego cheese.

The influence of two proteinases (Bacillus subtilis neutral proteinase and Micrococcus sp. cysteine proteinase) and two starter culture levels (0.1% and 1%) on biogenic amine formation has been studied in raw ewes' milk Manchego cheese. Amino acid decarboxylating micro-organisms were determined on tyrosine enriched selective media. Biogenic amines were analysed by capillary electrophoresis in citrate buffer at pH 3.6. Addition of proteinases and level of starter culture did not influence the population of micro-organisms with amino acid decarboxylating activity, which represented on average 1% of the bacterial population in 30-day-old cheeses. Tyramine and histamine were detected in all batches of cheese from day 30. Concentrations of tyramine and histamine were higher in cheeses made from milk with neutral proteinase (up to 356 and 284 mg kg(-1), respectively, after 90 days) than in cheeses made from milk with cysteine proteinase (up to 269 and 189 mg kg(-1), respectively) or with no proteinase added (up to 305 and 226 mg kg(-1), respectively). Formation of tyramine and histamine was also favoured in cheeses made with 1% starter culture with respect to cheeses made with only 0.1% starter culture, probably due to the higher pH values of the former cheeses. After 90 days of ripening, concentrations of 10-20 mg kg(-1) phenylethylamine were observed in 9 of the 12 batches, and levels < 10 mg kg(-1) tryptamine were only detected in 3 batches, with no significant relationship between the concentration of these amines and proteinase addition or level of starter culture.

Animals↗
PubMed1999

Improved screening procedure for biogenic amine production by lactic acid bacteria.

An improved screening plate method for the detection of amino acid decarboxylase-positive microorganisms (especially lactic acid bacteria) was developed. The suitability and detection level of the designed medium were quantitatively evaluated by confirmation of amine-forming capacity using an HPLC procedure. The potential to produce the biogenic amines (BA) tyramine, histamine, putrescine, and cadaverine, was investigated in a wide number of lactic acid bacteria (LAB) of different origin, including starter cultures, protective cultures, type strains and strains isolated from different food products. Also, several strains of Enterobacteriaceae were examined. Modifications to previously described methods included lowering glucose and sodium chloride concentrations, and increasing the buffer effect with calcium carbonate and potassium phosphate. In addition, pyridoxal-5-phosphate was included as a codecarboxylase factor for its enhancing effect on the amino acid decarboxylase activity. The screening plate method showed a good correlation with the chemical analysis and due to its simplicity it is presented as a suitable and sensitive method to investigate the capacity of biogenic amine production by LAB. Tyramine was the main amine formed by the LAB strains investigated. Enterococci, carnobacteria and some strains of lactobacilli, particularly of Lb. curvatus. Lb. brevis and Lb. buchneri, were the most intensive tyramine formers. Several strains of lactobacilli, Leuconostoc spp., Weissella spp. and pediococci did not show any potential to produce amines. Enterobacteriaceae were associated with cadaverine and putrescine formation. No significant histamine production could be detected for any of the strains tested.

Aromatic-L-Amino-Acid Decarboxylases↗
PubMed2000

Analysis of biogenic amines in microdialysates of the brain.

Microdialysis is a method of sampling a liquid compartment by means of a hollow fibre dialysis membrane. The method was developed in the 1980s as a technique for sampling the extracellular fluid of the brain of conscious animals. When used in combination with sensitive analytical chemical tools, microdialysis can be used to study the regulation of neurotransmission in the living brain. Here we describe the application of microdialysis for sampling and detection of biogenic amines (dopamine, noradrenaline and serotonin) in brain tissue. A short overview of the microdialysis technique and its applications are given. In addition, the analytical chemical methods that are currently used to assay biogenic amines in dialysates are briefly discussed.

Animals↗
PubMed1997

Effects of beta-adrenoceptor blocker pindolol, calcium antagonist verapamil and their combination on retention in step-down- and shuttle-box-trained rats and on brain biogenic monoamines.

The effects of the beta-adrenoceptor blocker pindolol and the calcium antagonist verapamil administered alone or in combination on retention in step-down- and shuttle-box-trained rats and on the biogenic monoamine levels in the frontal cortex and hippocampus were examined. The chronic oral treatment with pindolol impaired retention in step-down- and shuttle-box-trained rats, decreasing the dopamine (DA) and noradrenaline (NA) levels and increasing the serotonin (5-HT) levels in the cortex and hippocampus. Verapamil did not influence retention in step-down- and shuttle-box avoidance situation and the biogenic monoamine levels in the frontal cortex and hippocampus. It should, however, be noted that the chronic oral treatment with verapamil completely abolished the retention-impairing effect of pindolol, restoring to normal DA, NA and 5-HT levels. These findings might be of interest to clinical practice and suggest the necessity for using a combination of beta-blockers with Ca2+ antagonists in case of prolonged treatment of cardiovascular diseases.

Adrenergic beta-Antagonists↗
PubMed2000

Uptake and release effects of diethylpropion and its metabolites with biogenic amine transporters.

Three metabolites of diethylpropion (1), (+/-)-2-ethylamino-1-phenyl-propan-1-one (2), (1R,2S)-(-)-N,N-diethylnorephedrine (3a) and (1S,2R)-(-)-N,N-diethylnorephedrine (3b) were synthesized. Their uptake and release effects with biogenic amine transporters were evaluated. A major finding of this study is that the in vivo activity of diethylpropion on biogenic amine transporters is most likely due to metabolite 2 as diethylpropion (1) and the metabolites 3a and 3b showed little or no effect in the assays studied. These studies also revealed that 2 acted as a substrate at the norepinephrine (IC50 = 99 nM) and serotonin transporters (IC50 = 2118 nM) and an uptake inhibitor at the dopamine transporter (IC50 = 1014 nM). The potent action of 2 at the NE transporter supports the hypothesis that amphetamine-type subjective effects may be mediated in part by brain norepinephrine.

Animals↗
PubMed2001

Changes of biogenic amine levels in haemolymph during diapausing and non-diapausing status in Pieris brassicae L.

During the larval development of Pieris brassicae, photoperiod status induces either direct (non-diapausing) development or diapausing development. Biogenic amines such as dopamine and serotonin and their derivatives may be implicated in the physiological control and adaptation of these insects to different photoperiods. High performance liquid chromatography coupled with electrochemical detection was used to measure biogenic amine concentrations in insect haemolymph in different photoperiod conditions. At the end of the higher photosensitivity phase, dopamine levels were two-fold higher in diapausing (0.914 pmol/microl+/-0.025) as compared to non-diapausing insects (0.415 pmol/microl+/-0.02; P<0.001). Globally, dopamine catabolites are found in higher levels in non-diapausing insects (in prepupa, near seven times more for NADA, and 25 times more for DOPAc), thus indicating a higher dopamine turn-over. Serotonin levels were detected only at the beginning of this instar in diapausing insects but not in direct development insects. During pupal life, dopamine levels were significantly higher in diapausing than in non-diapausing insects (in 3-day pupae, dopamine was 28 times higher), and remained at high levels throughout diapausing life. At the beginning of diapause, serotonin levels were higher in diapausing insects than in non-diapausing insects (in 3-day pupae, serotonin was 13 times higher). These levels decreased in the middle of diapause period, and then increased just before its breaking. Dopamine and serotonin levels presented the typical kinetics of diapause development and may be used as an indicator of the evolution of diapause status.

3,4-Dihydroxyphenylacetic Acid↗
PubMed2002

Comparison of a capillary electrophoresis method with high-performance liquid chromatography for the determination of biogenic amines in various food samples.

A capillary electrophoresis (CE) and a high-performance liquid chromatography (HPLC) method to analyze biogenic amines in food were compared. An automated precolumn derivatization with o-phthaldialdehyde (OPA) allows for the determination of aliphatic amines and amino acids by HPLC. In contrast, for the measurement of histamine and tyramine by CE, no laborious sample pretreatment was necessary. The biogenic amines were separated by CE or HPLC in less than 9 or 20 min, respectively. The calibration curves were linear to at least 100 mg/kg (r=0.999) and 1,000 mg/kg for HPLC and CE, respectively, with detection limits for histamine of 0.5 mg/kg (fluorescence detector) or 1 mg/kg (diode array detector) with HPLC and 2 mg/kg with CE. The detection limits for tyramine were 1.5 mg/kg with HPLC and 6 mg/kg with CE and for further amines (e.g., putrescine, spermidine, cadaverine, agmatine) ranging from 1.0 to 8.5 mg/kg with HPLC. There was a good correlation between CE and HPLC (correlation coefficient for histamine: 0.994).

Biogenic Amines↗
PubMed2003

Micellar electrokinetic capillary chromatography-electrochemical detection for analysis of biogenic amines in Drosophila melanogaster.

Micellar electrokinetic chromatography coupled to amperometric electrochemical detection was used to investigate the chemical environment of the fruit fly, Drosophila melanogaster. Preliminary studies focused on the employment and optimization of the system to separate electroactive amine-containing molecules present in the head and body of male and female flies. Ultimately, biogenic amines significant to the fly including L-3,4-dihydroxyphenylalanine, dopamine, tyramine, and serotonin were identified and their relative abundance quantified. Transgenic Drosophila with functionally ablated dopamine and serotonin neurons were analyzed to demonstrate the sensitivity of the technique. The separation method developed in this study should offer an advantage in elucidating the critical role that electroactive biogenic amines play in complex physiological processes correlated with Drosophila behavior.

Animals↗