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Biogenic Amines (biogenic + amine)
Terms modified by Biogenic Amines Selected AbstractsCharacterization of Biogenic Amines and Factors Influencing Their Formation in Traditional Chinese SausagesJOURNAL OF FOOD SCIENCE, Issue 6 2010Shiling Lu Abstract:, Biogenic amines in 42 traditional Chinese sausage samples obtained from different regions were determined by HPLC. The result showed that cadaverine was the major amine, followed by tyramine and putrescine. A total of 4 groups of samples were identified on the basis of total amines by cluster analysis. Group A included samples showing low amine contents (76.5 to 220 mg/kg) and accounted for 28.5% of the sausages examined. Group B included samples with moderate amine contents (220 to 600 mg/kg) and accounted for 45.2%. Group C included 11.9% of the samples showing high total biogenic amines contents (600 to 1000 mg/kg) and group D contained 14.28% of the samples showing very high levels of biogenic amines (higher than 1000 mg/kg). High correlation coefficients were found between the total counts of,Enterobacteria,and concentrations of total biogenic amines (r,= 0.73). Sanitary quality of raw materials and the specific flora are import factors influencing biogenic amines formation in traditional Chinese sausages. Practical Application: Biogenic amines are considered potentially harmful substances to human health worldwide and are usually found in fermented sausage.Traditional Chinese sausage is one form of spontaneously fermented sausage and manufactured in small-scale plants following spontaneous fermentation. Little information, however, exists on the traditional Chinese sausage. [source] Irradiation Effects on Biogenic Amines in Korean Fermented Soybean Paste During FermentationJOURNAL OF FOOD SCIENCE, Issue 1 2003J.-H. Kim ABSTRACT: Irradiation effects on biogenic amines (BAs) and microbiological populations of Korean fermented soybean paste were investigated during fermentation. Soybean paste was prepared and irradiated with doses of 5,10, and 15 kGy, and then fermented at 25 °C for 12 wk. Bacillus spp. and lactic-acid bacteria decreased by irradiation but increased during fermentation. Biogenic amines detected were putrescine, cadaverine, ,-phenylethylamine, spermidine, spermine, tryptamine, histamine, tyramine, and agmatine. A significant difference was not observed in BA content between control and irradiated samples immediately after gamma irradiation. However, 4 kinds of BAs, putrescine, tryptamine, spermidine, and histamine, showed significant reduction by irradiation during fermentation (P < 0.05). [source] Profile of Biogenic Amines in Goat Cheese Made from Pasteurized and Pressurized MilksJOURNAL OF FOOD SCIENCE, Issue 8 2002S. Novella-Rodríguez ABSTRACT: The formation of biogenic amines in goat cheese can be prevented through ensuring hygiene in raw materials and during manufacture, thereby avoiding potential decarboxylating microorganisms. High-pressure treatment may be used to inactivate microorganisms and is a potential alternative to pasteurization. This treatment could provoke higher proteolysis than pasteurization, leading to a higher availability of biogenic amine precursors. We compared the biogenic amine profile throughout the ripening of goat cheese made from pressurized milk with that obtained from pasteurized milk. Results indicate that the profile of biogenic amines is very similar for both cheeses. Tyramine was the prevailing amine in both cheeses, followed by cadaverine, putrescine, and histamine. [source] Development of Biogenic Amines in Yellowfin Tuna (Thunnus albacares): Effect of Storage and Correlation with Decarboxylase-Positive Bacterial FloraJOURNAL OF FOOD SCIENCE, Issue 1 2002W.-X. Du ABSTRACT: The effects of storage at 0,4,10, and 22°C for 0,1,3,5, and 9 d on the quality of yellowfin tuna fillets as determined by microbiological assessment, development of some biogenic amines, and sensory analysis were studied. Tuna fillets stored at 22 °C for 3 d, 10 °C for 5 d, and 4 °C for 9 d were rated unacceptable for consumption. Those stored at 22 °C for 3 d had total aerobic bacterial count of > 8 log10 CFU/g, a histamine-producing bacterial population of 7 log10 CFU/g, and 832 ppm of histamine, 35.8 ppm of putrescine, and 147 ppm of cadaverine. A comparison of the capillary electrophoresis, AOAC fluorometric method, and gas chromatography showed a very good correlation (r2 > 0.99) among these 3 methods for histamine quantitation in tuna samples. Morganella morganii, Enterobacter agglomerans, Enterobacter intermedium, Pseudomonas fluorescens, Proteins vulgaris, and Serratia liquefaciens were the decarboxylase-positive bacterial species isolated by using the Niven's medium and identified during storage, which were responsible for histamine production in test tuna fillets. [source] Effects of Salinity on Biogenic Amines, Hemolymph Osmotic Pressure, and Activity of Gill's Na+/K+ -ATPase in Charybdis japonica (Crustacea, Decapoda)JOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 6 2008Liu Hong-Yu The effects of salinity on hemolymph osmotic pressure, gill Na+/K+ -ATPase activity and dopamine (DA), norepinephrine (NE), serotonin (5-HT) in the gills, and hemolymph of the adult Charybdis japonica were studied. DA levels increased significantly (P < 0.05), while the NE and 5-HT revealed contrary change in hemolymph and gills. The iso-osmotic point of C. japonica (911.4 mOsm/kg) was at salinity of 27.87 ppt. The Na+/K+ -ATPase activity of gill showed negative correlation with salinity in the hypotonic environment (<27.87 ppt). The results of this experiment indicated that C. japonica had great capability to acclimate to low salinity. [source] Expression of histamine receptors and effect of histamine in the rat carotid body chemoafferent pathwayEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2006Nikolai Lazarov Abstract Chemosensory information from peripheral arterial oxygen sensors in the carotid body is relayed by petrosal ganglion neurons to the respiratory networks in the medulla oblongata. Biogenic amines, including histamine, released from glomus (type I) cells of the carotid body are considered to be primary transmitters in hypoxic chemosensitivity. Immunocytochemistry at light-and electron-microscopical levels, and RT-PCR, revealed the expression of histamine receptors 1 and 3 as well as histidine decarboxylase in the rat carotid body glomus cells and petrosal ganglion neurons. Histamine receptors 1 and 3, but not histidine decarboxylase, were also observed in the ventrolateral, intermediate and commissural subnuclei of the nucleus tractus solitarii in the medulla oblongata. In order to examine the possible role of histamine in the afferent branch of the respiratory system, we applied histamine receptor 1 and 3 agonists to the carotid body, which caused a mildly increased phrenic nerve activity in a working heart,brainstem preparation. Moreover, microinjection of antagonists of histamine receptors 1 and 3 into the nucleus tractus solitarii caused significant changes in the inspiratory timing and the chemoreceptor response. Our data show that histamine acting via histamine receptors 1 and 3 plays an important neuromodulatory role in the afferent control of chemosensitivity. [source] BIOGENIC AMINE CONTENT OF SOME TURKISH CHEESESJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 4 2002FÜGEN DURLU-ÖZKAYA Biogenic amines in ten samples of Ka,ar (aged), five samples of Ka,ar (fresh), four samples of Mihaliç, nine samples of Van Otlu (herbed), nine samples of Örgü, nine samples of Urfa and six samples of Civil cheeses were obtained from local supermarkets of Ankara. Tryptamine (TRY), phenylethylamine (PHA), putrescine (PUT), cadaverine (CAD), histamine (HIT), tyramine (TYA), spermine (SPM) and spermidine (SPD) contents of Turkish cheese samples were screened by high performance liquid chromatography (HPLC). PUT, CAD, HIT, TYA and SPD were the predominant biogenic amines in maturated Ka,ar (aged), vacuum-packed Ka,ar (fresh), Mihaliç, Otlu (herbed) and Örgü cheeses. PHA, CAD, TYA and SPD were the predominant biogenic amines in Urfa cheese samples. Civil cheeses were found to contain the highest HIT and TYA content with an average of 94.76 mg/100 g and 138.16 mg/100 g, respectively, much higher than the toxic dose. HIT level of Mihaliç cheeses were also higher than the accepted limit. The concentration of amines in all other cheeses was much lower than the toxic dose limits. [source] Characterization of Biogenic Amines and Factors Influencing Their Formation in Traditional Chinese SausagesJOURNAL OF FOOD SCIENCE, Issue 6 2010Shiling Lu Abstract:, Biogenic amines in 42 traditional Chinese sausage samples obtained from different regions were determined by HPLC. The result showed that cadaverine was the major amine, followed by tyramine and putrescine. A total of 4 groups of samples were identified on the basis of total amines by cluster analysis. Group A included samples showing low amine contents (76.5 to 220 mg/kg) and accounted for 28.5% of the sausages examined. Group B included samples with moderate amine contents (220 to 600 mg/kg) and accounted for 45.2%. Group C included 11.9% of the samples showing high total biogenic amines contents (600 to 1000 mg/kg) and group D contained 14.28% of the samples showing very high levels of biogenic amines (higher than 1000 mg/kg). High correlation coefficients were found between the total counts of,Enterobacteria,and concentrations of total biogenic amines (r,= 0.73). Sanitary quality of raw materials and the specific flora are import factors influencing biogenic amines formation in traditional Chinese sausages. Practical Application: Biogenic amines are considered potentially harmful substances to human health worldwide and are usually found in fermented sausage.Traditional Chinese sausage is one form of spontaneously fermented sausage and manufactured in small-scale plants following spontaneous fermentation. Little information, however, exists on the traditional Chinese sausage. [source] Irradiation Effects on Biogenic Amines in Korean Fermented Soybean Paste During FermentationJOURNAL OF FOOD SCIENCE, Issue 1 2003J.-H. Kim ABSTRACT: Irradiation effects on biogenic amines (BAs) and microbiological populations of Korean fermented soybean paste were investigated during fermentation. Soybean paste was prepared and irradiated with doses of 5,10, and 15 kGy, and then fermented at 25 °C for 12 wk. Bacillus spp. and lactic-acid bacteria decreased by irradiation but increased during fermentation. Biogenic amines detected were putrescine, cadaverine, ,-phenylethylamine, spermidine, spermine, tryptamine, histamine, tyramine, and agmatine. A significant difference was not observed in BA content between control and irradiated samples immediately after gamma irradiation. However, 4 kinds of BAs, putrescine, tryptamine, spermidine, and histamine, showed significant reduction by irradiation during fermentation (P < 0.05). [source] Matrix effects on accurate mass measurements of low-molecular weight compounds using liquid chromatography-electrospray-quadrupole time-of-flight mass spectrometry,JOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 3 2006F. Calbiani Abstract Liquid chromatography (LC) with high-resolution mass spectrometry (HRMS) represents a powerful technique for the identification and/or confirmation of small molecules, i.e. drugs, metabolites or contaminants, in different matrices. However, reliability of analyte identification by HRMS is being challenged by the uncertainty that affects the exact mass measurement. This parameter, characterized by accuracy and precision, is influenced by sample matrix and interferent compounds so that questions about how to develop and validate reliable LC-HRMS-based methods are being raised. Experimental approaches for studying the effects of various key factors influencing mass accuracy on low-molecular weight compounds (MW < 150 Da) when using a quadrupole-time-of-flight (QTOF) mass analyzer were described. Biogenic amines in human plasma were considered for the purpose and the effects of peak shape, ion abundance, resolution and data processing on accurate mass measurements of the analytes were evaluated. In addition, the influence of the matrix on the uncertainty associated with their identification and quantitation is discussed. A critical evaluation on the calculation of the limits of detection was carried out, considering the uncertainty associated with exact mass measurement of HRMS-based methods. The minimum concentration level of the analytes that was able to provide a statistical error lower than 5 ppm in terms of precision was 10 times higher than those calculated with S/N = 3, thus suggesting the importance of considering both components of exact mass measurement uncertainty in the evaluation of the limit of detection. Copyright © 2006 John Wiley & Sons, Ltd. [source] Age- and subcaste-related patterns of serotonergic immunoreactivity in the optic lobes of the ant Pheidole dentataDEVELOPMENTAL NEUROBIOLOGY, Issue 11 2008Marc A. Seid Abstract Serotonin, a biogenic amine known to be a neuromodulator of insect behavior, has recently been associated with age-related patterns of task performance in the ant Pheidole dentata. We identified worker age- and subcaste-related patterns of serotonergic activity within the optic lobes of the P. dentata brain to further examine its relationship to polyethism. We found strong immunoreactivity in the optic lobes of the brains of both minor and major workers. Serotonergic cell bodies in the optic lobes increased significantly in number as major and minor workers matured. Old major workers had greater numbers of serotonergic cell bodies than minors of a similar age. This age-related increase in serotonergic immunoreactivity, as well as the presence of diffuse serotonin networks in the mushroom bodies, antennal lobes, and central complex, occurs concomitantly with an increase in the size of worker task repertoires. Our results suggest that serotonin is associated with the development of the visual system, enabling the detection of task-related stimuli outside the nest, thus playing a significant role in worker behavioral development and colony-wide division of labor. © 2008 Wiley Periodicals, Inc. Develop Neurobiol, 2008. [source] Safety and Functional Aspects of Preselected Enterococci for Probiotic Use in Iberian Dry-Fermented SausagesJOURNAL OF FOOD SCIENCE, Issue 7 2009Santiago Ruiz-Moyano ABSTRACT:, The purpose of this study was to investigate enterococci for potential probiotic use in Iberian dry-fermented sausages. A total of 15 strains isolated from Iberian dry-fermented sausages, human feces, and pig feces were evaluated for their safety and functional characteristics including biogenic amine (BA) production, antibiotic susceptibility, hemolysis, virulence determinants, cell adhesion, and antimicrobial activity against foodborne pathogens. The strain,Enterococcus faecium,SE906 was able to establish itself on the intestinal epithelium, inhibiting such pathogenic bacteria as,Listeria monocytogenes in vitro. This strain was also considered safe to be used for its low aminogenic potential, and its antibiotic resistance pattern and virulence determinants, being identified as a potential probiotic meat starter culture suitable for manufacture of dry-fermented Iberian sausages. [source] Regulated trafficking of neurotransmitter transporters: common notes but different melodiesJOURNAL OF NEUROCHEMISTRY, Issue 1 2002Michael B. Robinson Abstract The activity of biogenic amine and amino acid neurotransmitters is limited by presynaptic and astrocytic Na+ -dependent transport systems. Their functional importance is underscored by the observation that these transporters are the targets of broad classes of psychotherapeutic agents, including antidepressants and stimulants. Early studies suggested that the activity of these transporters can be fine tuned by a number of different signaling pathways. In the past five years, several groups have provided compelling evidence that changing the cell surface availability of these transporters contributes to this fine tuning. This regulated trafficking can result in rapid (within minutes) increases or decreases in the plasma membrane expression of these transporters and is independent of transcriptional or translational control mechanisms. Many of the same signaling molecules, including protein kinase C (PKC), tyrosine kinase, phosphatidylinositol 3-kinase (P13-K), and protein phosphatase, regulate the transporters for different neurotransmitters. In addition to these classical receptor activated pathways, transporter substrates also regulate activity and cell surface expression of these transporters. In fact, some of the transporters form complexes with signaling molecules. Given the functional and genetic similarities of these transporters, it is not surprising that the same signaling molecules regulate their trafficking, but except for the molecules, the actual effects on individual transporters are remarkably different. It,is as if the same musical notes have been rearranged into several different melodies. [source] Prenatal protein malnourished rats show changes in sleep/wake behavior as adultsJOURNAL OF SLEEP RESEARCH, Issue 1 2000Subimal Datta SUMMARY Prenatal protein malnutrition significantly elevates brain levels of serotonin in rats, and these levels remain elevated throughout their lives. This biogenic amine is involved in the regulation of many physiological functions, including the normal sleep/wake cycle. The present study examined the effects of prenatal protein malnutrition on the sleep/wake cycle of freely moving adult rats. Six prenatally protein malnourished (6% casein) and 10 well-nourished (25% casein) male rats (90,120-day-old) were chronically implanted with a standard set of electrodes (to record cortical electroencephalogram, neck muscle electromyogram, electrooculogram, and hippocampal theta wave) to objectively measure states of sleep and wakefulness. Six-hour polygraphic recordings were made between 10.00 and 16.00 h; a time when the rats normally sleep. Prenatally malnourished rats spent 20% more time in slow wave sleep (SWS) compared to the well-nourished rats. The total percentage of time spent in rapid eye movement (REM) sleep was 61% less in prenatally malnourished rats compared to well-nourished control rats. These findings demonstrate the adverse consequences of prenatal protein malnutrition on the quality and quantity of adult sleep in rats. These sleep changes are potentially detrimental to normal social behavior and cognitive functions. Prenatally malnourished rats are an excellent animal model to study the role of endogenous serotonin in the regulation of the normal sleep/wake cycle. [source] Investigation of the effect of sumac extract and BHT addition on the quality of sucuk (Turkish dry-fermented sausage)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 5 2006Hüseyin Bozkurt Abstract The effect of sumac extract and BHT (butylated hydroxytoluene) addition on the quality (pH, colour, biogenic amine, TBARS values and sensory attributes) of sucuk (Turkish dry-fermented sausage) were investigated during the ripening period. Addition of BHT decreased the TBARS value by about 23.7%, whereas sumac extract decreased it by 42.0%. Sumac extract decreased (P < 0.05) putrescine formation more than BHT addition. However, no significant difference (P > 0.05) was observed in histamine formation for both the sumac extract and BHT-added recipe. The highest tyramine concentration was observed in a control recipe (R1) prepared without any antioxidants, and the lowest was in the sumac extract-added recipe (R3) with mean values of about 96.62 and 63.17 mg kg,1, respectively. The control recipe (R1) was found to be the worst (P < 0.05) sample with respect to overall sensory quality and addition of either sumac extract or BHT increased (P < 0.05) the overall sensory quality of sucuk. The pH and colour attributes of sucuk were not significantly different (P > 0.05) between the addition of sumac extract and BHT. This study demonstrated that sumac extract had more effect on the quality of sucuk during the ripening period, hence it could be easily utilised in sucuk to enhance quality. Copyright © 2006 Society of Chemical Industry [source] Orexins/hypocretins and aminergic systemsACTA PHYSIOLOGICA, Issue 3 2010K. S. Eriksson Abstract Orexin/hypocretin neurones in the posterior hypothalamus are mutually connected with noradrenergic, serotonergic, dopaminergic, histaminergic, and cholinergic neurone systems. They activate these targets by direct post-synaptic and indirect pre-synaptic mechanisms and in turn receive inhibitory feedback and excitatory feed forward control. With respect to behavioural state control, orexin/hypocretin neurones are conducting the orchestra of biogenic amines. This review highlights the role of these players in the control of energy administration, sleep,wake architecture, cortical activation, plasticity, and memory functions in health and disease. [source] Pulsed Amperometric Detection of Histamine at Glassy Carbon Electrodes Modified with Gold NanoparticlesELECTROANALYSIS, Issue 4 2005V. Carralero Abstract Gold nanocrystal-modified glassy carbon electrodes (nAu-GCE) were prepared and used for the determination of histamine by flow injection and high performance liquid chromatography using pulsed amperometric detection (PAD) as the detection mode. Experimental variables involved in the electrodeposition process of gold from a HAuCl4 solution were optimized. A catalytic enhancement of the histamine voltammetric response was observed at the nAu-GCE when compared with that obtained at a conventional Au disk electrode, as a consequence of the microdispersion of gold nanocrystals on the GC substrate. The morphological and electrochemical characteristics of the nAu-GCE were evaluated by SEM and cyclic voltammetry. PAD using a very simple potential waveform consisting of an anodic potential (+700,mV for 500,ms) and a cathodic potential (,300,mV for 30,ms), was used to avoid the electrode surface fouling when histamine was detected under flowing conditions. Flow injection amperometric responses showed much higher Ip values and signal-to-noise ratios at the nAu-GCE than at a conventional gold disk electrode. A limit of detection of 6×10,7,mol L,1 histamine was obtained. HPLC-PAD at the nAu-GCE was used for the determination of histamine in the presence of other biogenic amines and indole. Histamine was determined in sardine samples spiked at a 50,,g g,1 concentration level, with good results. Furthermore, the chromatographic PAD method was also used for monitoring the formation of histamine during the decomposition process of sardine samples. [source] Recent advances in the application of capillary electromigration methods for food analysis and FoodomicsELECTROPHORESIS, Issue 1 2010Miguel Herrero Abstract The use of capillary electromigration methods to analyze foods and food components is reviewed in this work. Papers that were published during the period April 2007 to March 2009 are included following the previous review by García-Cańas and Cifuentes (Electrophoresis, 2008, 29, 294,309). These works include the analysis of amino acids, biogenic amines, peptides, proteins, DNAs, carbohydrates, phenols, polyphenols, pigments, toxins, pesticides, vitamins, additives, small organic and inorganic ions and other compounds found in foods and beverages, as well as those applications of CE for monitoring food interactions and food processing. The use of microchips, CE-MS, chiral-CE as well as other foreseen trends in food analysis are also discussed including their possibilities in the very new field of Foodomics. [source] Capillary electrophoretic separation of biologically active amines and acids using nanoparticle-coated capillariesELECTROPHORESIS, Issue 9 2008Yu-Fen Huang Abstract This manuscript describes dynamic coating of capillaries with poly(L -lysine) (PLL) and silica nanoparticles (SiO2 NPs) and use of the as-prepared capillaries for the separation of biogenic amines and acids by CE in conjunction with LIF detection. The directions of EOF are controlled by varying the outmost layer of the capillaries with PLL and SiO2 NPs, respectively. Over the pH range 3.0,5.0, the (PLL,SiO2NP)n,PLL capillaries have an EOF toward the anodic end and are more suitable for the separation of acids with respect to speed, while the (PLL,SiO2NP)n capillaries have an EOF toward the cathodic end and are more suitable for the separation of biogenic amines regarding speed and sensitivity. The separations of standard solutions containing five amines and two acids by CE with LIF detection using (PLL,SiO2NP)2,PLL and (PLL,SiO2NP)3 capillaries were accomplished within 10 and 7,min, providing plate numbers of 3.8 and 5.0×104,plates/m for 5-hydroxytryptamine (5-HT), respectively. The LODs for 5-HT and 5-hydroxyindole-3-acetic acid (5-HIAA) are 32 and 2,nM and 0.2 and 1.5,nM when using the (PLL,SiO2NP)2,PLL and (PLL,SiO2NP)3 capillaries, respectively. Identification and quantification of 5-HIAA, homovanillic acid, and DL -vanillomandelic acid in urine samples from a male before and after drinking green tea were tested to validate practicality of the present approach. The results show that the (PLL,SiO2NP)2,PLL capillary provides greater resolving power, while the (PLL,SiO2NP)3 capillary provides better sensitivity, higher efficiency, and longer durability for the separation of the amines and acids. [source] Determination of biogenic amines in HeLa cell lysate by 6-oxy-(N -succinimidyl acetate)-9-(2',methoxycarbonyl) fluorescein and micellar electrokinetic capillary chromatography with laser-induced fluorescence detectionELECTROPHORESIS, Issue 4 2006Liwei Cao Abstract An MEKC-LIF method using 6-oxy-(N -succinimidyl acetate)-9-(2'-methoxy-carbonyl) fluorescein (SAMF) newly synthesized in our lab as a labeling reagent for the separation and determination of eight typical biogenic amines was proposed. After careful study of the derivatization condition such as pH value, reagent concentration, temperature, and reaction time, derivatization reaction was accomplished as quickly as 10,min with stable yield. Optimal separation of SAMF-labeled amines was achieved with a running buffer (pH,9.3) containing 30,mM boric acid, 25,mM SDS, and 20%,v/v ACN. The proposed method allowed biogenic amines to be determined with LODs as low as 0.25,2.5,nmol/L and RSD values from 0.4 to 4.5%. The present method has been successfully used to monitor biogenic amines in HeLa cells and fish samples. This study exploits the potential of MEKC-LIF with SAMF labeling as a tool for monitoring biogenic amines involved in complex physiological and behavioral processes in various matrices. [source] Analytical potential of 6-oxy-(N -succinimidyl acetate)-9-(2'-methoxycarbonyl) fluorescein for the determination of amino compounds by capillary electrophoresis with laser-induced fluorescence detectionELECTROPHORESIS, Issue 10 2005Liwei Cao Abstract The analytical potential of a fluorescein analogue, 6-oxy-(N -succinimidyl acetate)-9-(2'-methoxycarbonyl) fluorescein (SAMF), for the first time synthesized in our laboratory, as a labeling reagent for the labeling and determination of amino compounds by capillary electrophoresis (CE) with laser-induced fluorescence (LIF) detection was investigated. Biogenic monoamines and amino acids were chosen as model analytes to evaluate the analytical possibilities of this approach. The derivatization conditions and separation parameters for the biogenic amines were optimized in detail. The derivatization was performed at 30°C for 6 min in boric acid buffer (pH 8.0). The derivatives were baseline-separated in 15 min with 25 mM boric acid running buffer (pH 9.0), containing 24 mM SDS and 12.5% v/v acetonitrile. The concentration detection limit for biogenic amines reaches 8×10,11 mol·L,1 (signal-to-noise ratio = 3). The application of CE in the analysis of the SAMF-derivatized amino acids was also exploited. The optimal running buffer for amino acids suggested that weak acidic background electrolyte offered better separation than the basic one. The proposed method was applied to the determination of biogenic amines in three different beer samples with satisfying recoveries varying from 92.8% to 104.8%. Finally, comparison of several fluorescein-based probes for amino compounds was discussed. With good labeling reaction, excellent photostability, pH-independent fluorescence (pH 4,9), and the resultant widely suited running buffer pH, SAMF has a great prospect in the determination of amino compounds in CE. [source] Integrated on-chip derivatization and electrophoresis for the rapid analysis of biogenic aminesELECTROPHORESIS, Issue 14 2004Nigel P. Beard Abstract We demonstrate the monolithic integration of a chemical reactor with a capillary electrophoresis device for the rapid and sensitive analysis of biogenic amines. Fluorescein isothiocyanate (FITC) is widely employed for the analysis of amino-group containing analytes. However, the slow reaction kinetics hinders the use of this dye for on-chip labeling applications. Other alternatives are available such as o -phthaldehyde (OPA), however, the inferior photophysical properties and the UV ,max present difficulties when using common excitation sources leading to a disparity in sensitivity. Consequently, we present for the first time the use of dichlorotriazine fluorescein (DTAF) as a superior in situ derivatizing agent for biogenic amines in microfluidic devices. The developed microdevice employs both hydrodynamic and electroosmotic flow, facilitating the creation of a polymeric microchip to perform both precolumn derivatization and electrophoretic analysis. The favorable photophysical properties of the DTAF and its fast reaction kinetics provide detection limits down to 1 nM and total analysis times (including on-chip mixing and reaction) of <60 s. The detection limits are two orders of magnitude lower than current limits obtained with both FITC and OPA. The optimized microdevice is also employed to probe biogenic amines in real samples. [source] Amphetamine-induced movement disorderEMERGENCY MEDICINE AUSTRALASIA, Issue 3 2005Michael A Downes Abstract Recreational use of amphetamines is common in Australia and New Zealand when compared with other developed nations. The clinical effects are variable because of the potential of these drugs to increase the proportion of different biogenic amines in the central nervous system (CNS). The substances affected are adrenaline, noradrenaline, serotonin and dopamine. Movement disorders represent one of the less common presentations of amphetamine toxicity but one that health care workers should be aware of nonetheless. [source] C1 neurons in the rat rostral ventrolateral medulla differentially express vesicular monoamine transporter 2 in soma and axonal compartmentsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 8 2008C. P. Sevigny Abstract Vesicular monoamine transporter 2 (VMAT2) packages biogenic amines into large dense core and synaptic vesicles for either somatodendritic or synaptic release from neurons of the CNS. Whilst the distribution of VMAT2 has been well characterized in many catecholaminergic cell groups, its localization amongst C1 adrenergic neurons in the medulla has not been examined in detail. Within the rostral ventrolateral medulla (RVLM), C1 neurons are a group of barosensitive, adrenergic neurons. Rostral C1 cells project to the thoracic spinal cord and are considered sympathetic premotor neurons. The majority of caudal C1 cells project rostrally to regions such as the hypothalamus. The present study sought to quantitate the somatodendritic expression of VMAT2 in C1 neurons, and to assess the subcellular distribution of the transporter. Immunoreactivity for VMAT2 occurred in 31% of C1 soma, with a high proportion of these in the caudal part of the RVLM. Retrograde tracing studies revealed that only two of 43 bulbospinal C1 neurons contained faint VMAT2-immunoreactivity, whilst 88 ± 5% of rostrally projecting neurons were VMAT2-positive. A lentivirus, designed to express green fluorescent protein exclusively in noradrenergic and adrenergic neurons, was injected into the RVLM to label C1 neurons. Eighty-three percent of C1 efferents that occurred in close proximity to sympathetic preganglionic neurons within the T3 intermediolateral cell column contained VMAT2-immunoreactivity. These data demonstrate differential distribution of VMAT2 within different subpopulations of C1 neurons and suggest that this might reflect differences in somatodendritic vs. synaptic release of catecholamines. [source] Physiological and oenological traits of different Dekkera/Brettanomyces bruxellensis strains under wine-model conditionsFEMS YEAST RESEARCH, Issue 7 2008Ileana Vigentini Abstract Contamination of wine by Dekkera/Brettanomyces bruxellensis is mostly due to the production of off-flavours identified as vinyl- and especially ethyl-phenols, but these yeasts can also produce several other spoiling metabolites, such as acetic acid and biogenic amines. Little information is available about the correlation between growth, viability and off-flavour and biogenic amine production. In the present work, five strains of Dekkera bruxellensis isolated from wine were analysed over 3 months in wine-like environment for growth, cell survival, carbon source utilization and production of volatile phenols and biogenic amines. Our data indicate that the wine spoilage potential of D. bruxellensis is strain dependent, being strictly associated with the ability to grow under oenological conditions. 4-Ethyl-phenol and 4-ethyl-guaiacol production ranged between 0 and 2.7 and 2 mg L,1, respectively, depending on the growth conditions. Putrescine, cadaverine and spermidine were the biogenic amines found. [source] Presence of biogenic amines in a traditional salted Italian cheeseINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 2 2009N INNOCENTE Asino cheese is a traditional Italian cheese ripened in a special dilute brine (salmuerie), mixed with whey, milk and milk cream. The aim of this work was to ascertain whether this processing technology can influence amine production. The study demonstrated that biogenic amine content increased gradually in the Asino cheese during the soaking phase in brine. Moreover, the biogenic amine content of the salmuerie was very high and the salmuerie and the Asino cheese had a similar relative profile in amine content. These results suggested that the biogenic amines migrate from the brine into the cheese as a result of the concentration differential existing between the two systems. [source] Salted and fermented fish processes evaluationINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 11 2009Cecília Riscado Pombo Summary Fish curing by salting and fermentation is the result of the action of certain enzymes over fresh fish. This study aimed to evaluate and compare three technological processing methods (A, B, C). Coliforms, Escherichia coli, Enterococcus spp., coagulase-positive Staphylococcus, Salmonella spp., total volatile base (TVB), pH, water activity (Wa), sodium chloride and biogenic amines were evaluated. A significant difference in histamine production (P < 0.05) was observed. Escherichia spp., Klebsiella spp, Proteus spp., Shigella spp., Citrobacter spp. and Pseudomonas spp. were isolated. Sodium chloride content varied between 15.65 and 18.87% and no significant difference was observed (P > 0.05). Wa and pH showed significant differences (P < 0.05), with values between 0.71 and 0.75, and 5.54 and 5.93. TVB values varied between 15.1 and 62.1 mg N 100 g,1, showing significant differences (P < 0.05) as well. Worrying levels of histamine were found. Processing method A was found to be the most appropriate for the production of this kind of fish. [source] The effects of ice storage on inosine monophosphate, inosine, hypoxanthine, and biogenic amine formation in European catfish (Silurus glanis) filletsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 10 2009Fatih Özogul Summary European catfish fillets in ice were evaluated by measuring nucleotide components and biogenic amine contents and these then compared with sensory and microbiological assessment during the 21 days of iced storage. Analyses were carried out using two different rapid HPLC methods for nucleotid degradation products and biogenic amine contents in European catfish fillets. Sensory evaluation showed that storage life of European catfish found to be 14,18 days. Initial inosine monophosphate (IMP) level was 12.6 ,mol g1 and then decreased during the rest of storage period. Inosine (INO) level increased rapidly until 7 days of storage. Hypoxanthine (Hx) level increased almost linearly with storage time. The most accumulated biogenic amines were putrescine, cadaverine, spermidine, spermine, and serotonin in all the European catfish fillets during the storage, although the formation of biogenic amines levels was fluctuated. Histamine was only detectable at 4 and 7 days of storage as low as 1 mg 100 g1 fish. Total viable count in European catfish increased rapidly with storage time and reached ,109 cfu g1 when the fillets were not acceptable for consumption. [source] Immunocytochemical evidence for biogenic amines and immunogold labeling of serotonergic synapses in tentacles of Aiptasia pallida (Cnidaria, Anthozoa)INVERTEBRATE BIOLOGY, Issue 4 2000Jane A. Westfall Abstract. Evidence for classical neurotransmitters in sea anemones remains controversial. We used high performance liquid chromatography with electrochemical detection (HPLC-EC) and electron microscopical imunocytochemistry to determine the presence of serotonin and precursor synthetic enzymes of other biogenic amines in tentacles of the sea anemone Aiptasia pallida. Using HPLC-EC we found dopamine and serotonin (5-hydroxytryptamine, 5-HT) in both tentacles and whole animal homogenates. Antibodies to tyrosine hydroxylase, dopamine ,-hydroxylase, phenylethanolamine N-methyltransferase, and 5-HT were used with the peroxidase-antiperoxidase method to reveal positive immunoreactivity to these substances in neurons of tentacles. Immunogold labeling of serial thin sections with the anti-5,HT antibody revealed reactive products in synaptic vesicles at interneuronal, neuromuscular, and neurospirocyte synapses. These results suggest that both catecholamine and indolamine neurotransmitters occur in sea anemones in addition to the neuropeptide Antho-RFamide, indicating the presence of multiple types of transmitter substances in an early nervous system. [source] Characterization of the Enterobacteriaceae isolated from an artisanal Italian ewe's cheese (Pecorino Abruzzese)JOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2006C. Chaves-López Abstract Aims:, To evaluate some physiological characteristics of the Enterobacteriaceae isolated from Pecorino cheese. Methods and Results:, The production of organic acids, secondary volatile compounds, biogenic amines (BA) and the lipolytic and proteolytic activities of Citrobacter braakii, Enterobacter sakazakii, Escherichia coli, Kluyvera spp., Salmonella enterica ssp. arizonae and Serratia odorifera strains were determined in skim milk after 48 h of fermentation at 30°C. The proteolytic activity observed only in Ser. odorifera and Kluyvera spp. was confirmed by the peptide profiles of the pH 4·6-insoluble fraction using RP-HPLC; however, the lipase activity was evidenced in all the isolates of E. coli, Kluyvera spp. and Salm. enterica ssp. arizonae. During fermentation, all the strains utilized citric acid and produced significant quantities of putrescine followed by histamine, spermine and spermidine as well as acetic and lactic acid. Moreover, the major volatile compounds produced were ethanol, 2,3-butanedione, 3-hydroxy-2-butanone, 2-heptanone and acetone. Conclusions:, The Enterobacteriaceae of dairy origin possess many metabolic activities that could affect the sensory quality of the cheese in which they grow during ripening. Significance and Impact of the Study:, The important physiological characteristics possessed by Enterobacteriaceae confirm the complexity of the microbiota of Pecorino Abruzzese cheese, which influences the typical sensory properties of this product. [source] | ||||||||||||||||||||||||||||