Determination Of Tyramine Research Articles

Simple and sensitive analysis of histamine and tyramine in Japanese soy sauces and their intermediates using the stable isotope dilution HILIC-MS/MS method.

We established a simple, sensitive, and reproducible method to analyze the histamine and tyramine levels in Japanese soy sauce and its mash (called moromi) using hydrophilic interaction liquid chromatography with tandem mass spectrometry (HILIC-MS/MS). Histamine and tyramine quantification was performed using their stable isotopes for electrospray ionization-tandem mass spectrometry in the selected reaction monitoring mode. The sample pretreatment process was a simple, one-step liquid-liquid extraction. HILIC separation was performed with a gradient elution of aqueous ammonium formate and acetonitrile. Because of validation tests, the linearity, the accuracies, and precisions were sufficient. The limit of detection and the limit of quantification were 0.09 and 0.29 ppm for histamine and 0.13 and 0.42 ppm for tyramine, respectively. We successfully applied this method to histamine and tyramine determination in four kinds of commercial Japanese soy sauces and also in moromi samples during soy sauce production.

Disposable Horseradish Peroxidase Biosensors for the Selective Determination of Tyramine

AbstractThis work reports the development of horseradish peroxidase based biosensors using screen‐printed carbon electrodes for the determination of tyramine (tyr). A novel procedure based on the insertion of the enzyme in the screen‐printing process (SPCHRPEs) has been compared with the cross‐linked immobilization into the carbon working electrode (HRP/SPCEs). Both biosensors were characterized obtaining good capability of detection (2.1±0.2 and 0.2±0.01 µM for SPCHRPEs and HRP/SPCEs, respectively). The reproducibility was 3.4 % and 6.8 % for SPCHRPEs and HRP/SPCEs, respectively. The repeatability was 2.2 % and 7.1 % for SPCHRPEs and HRP/SPCEs, respectively. The specificity towards different biogenic amines was analyzed. The developed biosensors were applied to the determination of tyr content in cheese samples.

Amperometric biosensor based on polypyrrole and tyrosinase for the detection of tyramine in food samples

An electrochemical tyrosinase electrode for detection of tyramine was developed via cross-linking immobilization method over phosphate-doped polypyrrole film. The enzyme tyrosinase immobilized over the polypyrrole thin film preserves well its biocatalytic activity. Tyramine was determined by the direct reduction of biocatalytically formed dopaquinone at −0.250V. The analytical characteristics of this biosensor, including linear range, detection limit, repeatability and storage stability are described. The kinetics of the enzymatic reaction fitted into a Michaelis–Menten type kinetic, as confirmed by the h parameter close to 1 obtained from the Hill's plot. Under the optimum conditions, the current response had a linear relationship with the concentration of tyramine in the range of 4–80×10−6M, with a sensitivity of 0.1069AM−1 and a limit of detection of 5.7×10−7M. The biosensor exhibited high repeatability and long term stability. Determination of tyramine in real samples showed good recovery. The selective detection is related to specific action of tyrosinase toward phenolic group from tyramine (1-hydroxy-4-ethylaminobenzene). The developed biosensor was applied to the determination of the tyramine content in sauerkraut samples.

Disposable amperometric biosensor for the determination of tyramine using plasma amino oxidase

We have developed screen–printed carbon electrodes for the determination of tyramine (Tyr) via plasma amine oxidase. The enzyme was immobilized on the carbon working electrode by cross–linking it with bovine serum albumin using glutaraldehyde. The employment of the mediator hydroxymethylferrocene lowers the working potential to +260 mV (vs. a screen–printed Ag/AgCl reference electrode). The effects of pH, potential and mediator concentration were optimized and resulted in reproducibility and repeatability values of 8.6 % and 8.7 %, respectively. Response is linear in the range from 2 to 164 μM, and the limit of detection is 2.0 ± 0.18 μM. The effects of potentially interfering biogenic amines such as putrescine, cadaverine, histamine, spermine, spermidine and tryptamine were also evaluated. The biosensor was successfully applied to the determination of Tyr in cheese.

Spoilage Detection with Biogenic Amine Biosensors, Comparison of Different Enzyme Electrodes

AbstractThree enzyme based amperometric biosensors for biogenic amines were applied for meat spoilage monitoring. With diamine oxidase (EC 1.4.3.6), the total biogenic amine content was measured. Monoamine oxidase A (EC 1.4.3.4) was used for determination of tyramine, tryptamine and phenylethylamine content. Putrescine was selectively detected with putrescine oxidase (EC 1.4.3.10). The enzymes were separately co‐immobilized on graphite electrodes with peroxidase and Os mediator (PVI7‐dme‐Os). A fast extraction method using special centrifugal separator was applied for pork and fish samples stored at different conditions. Although partial extraction was achieved, the results correlate with total biogenic amine content measured by HPLC method.

Amperometric determination of tyramine in sauce and beer by epoxy resin biocomposite membrane bound tyramine oxidase

A method is described for construction of an amperometric biosensor for specific determination of tyramine, using black gram tyramine oxidase immobilized covalently on an epoxy resin membrane. The biosensor had optimum response within 10 s at pH 8.5 and 35 °C. A linear relationship was observed between tyramine concentrations and current (mA) in the range of 0.24 to 3.47 mg/dL. The biosensor was employed for determination of tyramine in beer and sauce. The detection limit of sensor was 0.24 mg/dL. The mean analytical recovery of added tyramine (0.5 and 1.0 mg/dL) was 97.3 ± 2.3 and 95.9 ± 3.4%. Within and between batch coefficient of variation were 5.1 and 5.34%, respectively. Enzyme electrode showed 35% loss in its initial activity after its regular use over a period of 2 months. The biosensor has the advantage that it does not suffer from leaching of enzyme and measures tyramine specifically.

Separation of adrenergic amines in Citrus aurantium L. var. amara by capillary electrochromatography using a novel monolithic stationary phase

This manuscript reports on the use of capillary electrochromatography for the determination of tyramine, (±) synephrine, and (±) octopamine, the major alkaloids in bitter orange peel. A novel methacrylate-based monolithic stationary phase was prepared by UV-photopolymerization in 100 μm id fused-silica capillaries. It facilitated the quantitative assessment of alkaloids with a mobile phase comprising aqueous 10 mM ammonium acetate in ACN and isopropanol. Applied voltage and temperature were 25 kV and 25°C, and samples were injected in electrokinetic mode. The method reported herein revealed adequate sensitivity (LOD ≤0.6 μg/mL), repeatability (σrel ≤4.1%), accuracy (recovery rates between 95.2 and 102.2%), and precision (intra-day variation ≤5.7%, inter-day variation ≤4.1%). The application of the CEC assay on C. aurantium var. amara plant material and dietary supplements, which usually are advertised for slimming properties, indicated that synephrine (0.17-0.82%) is the dominant alkaloid.

A molecularly imprinted electrochemical sensor based on multiwalled carbon nanotube-gold nanoparticle composites and chitosan for the detection of tyramine

A novel sensitive molecularly imprinted electrochemical sensor has been developed for selective detection of tyramine by combination of multiwalled carbon nanotube-gold nanoparticle (MWCNT-AuNP) composites and chitosan. MWCNT-AuNP composites were introduced for the enhancement of electronic transmission and sensitivity. Chitosan acts as a bridge for the imprinted layer and the MWCNT-AuNP composites. The molecularly imprinted polymer (MIP) was synthesized using tyramine as the template molecule, silicic acid tetracthyl ester and triethoxyphenylsilane as the functional monomers. The molecularly imprinted film displayed excellent selectivity towards tyramine. Under the optimum conditions, the current response had a linear relationship with the concentration of tyramine in the range of 1.08×10−7 to 1×10−5mol/L, with a limit of detection 5.7×10−8mol/L. The proposed sensor exhibited excellent repeatability, which was better than the result from previous literature. The relative standard deviation (RSD) of the repeated experiments for tyramine (5mmol/L) was 7.0%. Determination of tyramine in real samples showed good recovery.

Modeling the Aminogenic Potential of Enterococcus faecalis EF37 in Dry Fermented Sausages through Chemical and Molecular Approaches

Amino acid decarboxylase activity of the Enterococcus faecalis strain EF37 was monitored during fermentation and ripening of a traditional dry fermented sausage from Northern Italy (Salame Veronese) by means of microbiological, chemical, and molecular approaches in relation to three technological factors: fermentation temperature, sodium chloride concentration, and amount of glucose added to the meat mixture. Besides the analytical determination of tyramine and phenylethylamine accumulation and the counts of enterococci, the presence and quantification of the tyrosine decarboxylase gene (tdc) and its mRNA transcript were also investigated by using real-time PCR. According to the mathematical models obtained, all of the three factors studied were statistically significant and microbiologically relevant for the early development of enterococci, although the fermentation temperature had a more relevant influence on the enterococcal viable cells of the ripened product. Sodium chloride concentration was the most determinant factor of the final tyramine and 2-phenylethylamine accumulation and also of the levels of tdc present in the final product. In contrast, an effect of glucose concentration on tdc expression was observed in the last period of ripening. Moreover, increasing amounts of sodium chloride and decreasing fermentation temperature resulted in a reduced tdc expression. This is the first time that bacterial tyrosine decarboxylase potential is directly examined through a molecular approach in a fermented meat. The quantification of tdc and its transcript can help to elucidate the critical steps and factors during food manufacturing at which bacterial aminogenesis is possible, thus allowing researchers to propose technological measures to control decarboxylase activities.

Simultaneous determination of tyramine and tryptamine and their precursor amino acids by micellar liquid chromatography and pulsed amperometric detection in wines

Two biogenic amines, tryptamine and tyramine, and their precursors, tryptophan and tyrosine, were determined by a liquid chromatographic procedure. A hybrid micellar mobile phase of sodium dodecyl sulphate (SDS) and 1-propanol, a C18 column and electrochemical detection were used. A pH study in the range of 3–9 was performed and pH 3 was finally selected in accordance with resolution and analysis time. Oxidation potential was also checked in the range 0.6–0.9 V: the maximum area obtained in all those potentials was at 0.8 V, which was selected to carry out the analysis using a sequence of pulsed amperometric detection waveform. The four compounds were resolved using a mobile phase of 0.15 M SDS–5% 1-propanol with an analysis time of 16 min. Repeatabilities and intermediate precision were evaluated at three different concentrations for each compound with RSD values lower than 2.6 and 4.8%, respectively. Limits of detection and quantification were also obtained within the 10–40 and 33–135 ng/ml ranges, respectively. Finally, the applicability of the procedure was tested in several types of wine and no matrix effect was observed. The possibility of direct sample introduction simplifies and greatly expedites the treatments with reduced cost, improving the accuracy of the procedures.

Determination of tyramine in cheese by LC–UV

An isocratic reversed-phase liquid chromatographic assay for tyramine has been developed. The method is based on the reaction of tyramine with 4-chloro-7-nitrobenzofurazan and measurement of the absorbance at 458 nm after chromatographic separation on a C-18 column. Optimum reaction conditions were investigated. A linear relationship was found between absorbance and concentration over the range 25–300 ng per 10 μl of tyramine. The method was applied to the determination of tyramine in cheese. The cheese sample was homogenized with 5% (w/v) HClO 4 extracted with ethyl acetate–acetone (2:1) and chromatographed on high performance liquid chromatography (HPLC) after derivatization reaction with NBD-Cl. The determination limit was 25 μg/g cheese. The mean recovery of tyramine from cheese was 98.0%.

Determination of tyramine in cheese by reversed-phase high-performance liquid chromatography with amperometric detection

Determination of tyramine in cheese by reversed-phase high-performance liquid chromatography with amperometric detection

Simultaneous Determination of Polyamines in Red Meat Fishes by High Performance Liquid Chromatography and Evaluation of Freshness

A method for simultaneous determination of tyramine, putrescine (Put), cadaverine (Cad), histamine (Hm), agmatine, tryptamine and spermidine was developed by means of high performance liquid chromatography of their fluorescent derivatives with o-phthalaldehyde and mercaptoethanol. When the changes in contents of polyamines were examined in the meats of mackerel and saury pike during storage at 10°, 5°, 0° and -1°C, Hm and Cad were found to be major products. During the storage of saury pike meat at low temperatures, Cad was produced primarily, followed by Hm, whose level increased remarkably with storage time, exceeded that of Cad and reached a concentration causing allergy-like food poisoning before and at the stage of initial decomposition. Cad, Put and volatile basic nitrogen (VBN) appear to be useful as potential indices for the freshness and decomposition of saury pike; the levels of Cad and Put exceeded 10mg/100g and 1mg/100g, respectively, and VBN reached the level of 24 to 28mg/100g at the stage of initial decomposition.

Changes of Tyramine during Storage and Spoilage of Anchovies

ABSTRACTA study was carried out on the evolution of tyramine throughout storage and spoilage at two different temperatures of canned anchovy semi‐preserves and anchovy homogenates. During storage an increase occurred in tyramine until a maximum concentration was reached, after which it began to decrease. The storage temperature did not significantly influence the maximum tyramine content reached, though refrigeration temperatures delayed the start of the increase. Determination of tyramine was not a good parameter for establishing the conservation or spoilage status of anchovies.

A Rapid Ion‐Pair HPLC Procedure for the Determination of Tyramine in Dairy Products

ABSTRACTA rapid high performance liquid chromatographic method for the determination of tyramine in dairy products was developed. The amine was extracted from foods with warm methanol, separated by ion‐pair reversed phase chromatography and quantitatively determinated after o‐phthalaldehyde post‐column derivatization with a fluorescence detector. The calibration curve for tyramine in the range of 20–400 ng was linear and reproducible. The overall recovery rates were satisfactory.

Determination of Tyramine in Foods by High Performance Liquid Chromatography with Fluorescence Detection

Determination of Tyramine in Foods by High Performance Liquid Chromatography with Fluorescence Detection

Determination of Tyramine in Cheese By Complexation with Titanium Tetrachloride

Determination of Tyramine in Cheese By Complexation with Titanium Tetrachloride

Gas-liquid chromatographic determination of tyramine in fermented food products

Gas-liquid chromatographic determination of tyramine in fermented food products

Analysis of the venom of the sydney funnel-web spider,Atrax robustus using gas chromatography mass spectrometry

Thirteen compounds have been identified using gas chromatography mass spectrometry in the venom of the Sydney funnel-web spider, Atrax robustus. The compounds were identified as their trimethylsilyl or pentafluoropropionate derivatives and were citric acid, lactic acid, phosphoric acid, glycerol, urea, glucose, gamma-aminobutyric acid, glycine, spermidine, spermine, tyramine and octopamine. Female venom contained trace quantities of 5-methyoxytryptamine which was not detected in male venom. Quantitative determination of tyramine and octopamine was achieved using chemical ionization (CH4) gas chromatography mass spectrometry and deuterated internal standards.

Adaptation of the Tyramine Method to Routine Cheese Analysis

Summary The determination of tyramine in cheese has involved a long tedious procedure. A number of changes have been made to shorten the method without loss of accuracy. These include elimination of initial fat extractions, greater dilution of cheese solutions to reduce emulsion formation, more rapid extraction and use of different quantities of cheese and reagents. These changes makethis method more adaptable for routine analysis of cheese.