Polyamines in food and their consequences for food quality and human health

Protection of originality of Tokaji Aszú: amines and organic acids in botrytized wines by high-performance liquid chromatography

Amine and organic acid composition of Aszú wines from the Tokaj region of Hungary, nonbotrytized Hungarian wines from different regions, and foreign botrytized wines were analyzed by high-performance liquid chromatography. Hungarian and foreign wines (36 Hungarian and seven foreign botrytized wines) were compared in different ways by calculation of ratios of given amine compounds, analyses of variance, principal component, and discriminant analysis. In wines, putrescine and in some samples 3-methyl-butylamine and/or phenyl ethylamine were found in remarkable concentrations, while in botrytized wines four other amines were verified in high concentration. Good separation between Aszú and foreign botrytized wines was found by calculation of the amine component's ratio. The first two principal components of the principal component analysis accounted for 77 and 84% of the total variance in the data of amines and acids, respectively. The component scores of samples grouped according to Aszú, foreign botrytized, and nonbotrytized wines. Linear discriminant analysis was used for differentiation of Aszú, foreign botrytized, and normal wines. Using nine amines and two acids as variables, the correct classification was 97.6%. On the basis of results, an objective evaluation method can be elaborated for quality control in order to protect the authenticity and origin of wine specialties made from botrytized grapes.

Biologically active polyamines in beef, pork and meat products: A review

Dietary polyamines (PAs) putrescine (PUT), spermidine (SPD) and spermine (SPM) participate in an array of roles in human metabolism. Nevertheless, under some physiological conditions they can be undesirable. Meat and meat products are among important sources of PAs in human nutrition, mainly of SPM. The usual contents of PUT, SPD and SPM in fresh beef and pork are <2, <5 and 20-40mgkg(-1), respectively. Current information on changes of PAs during meat storage corresponds with PUT formation by bacterial activity mainly of pseudomonads and Enterobacteriaceae. However, data on SPD and SPM changes during meat chill-storage have been inconsistent. Culinary processing of meat probably does not change SPD and SPM levels. PUT can be formed in different meat products in relation to the microbial population of the raw materials used and the hygienic level of manufacturing process. SPD and SPM contents seem to remain stable during processing of non-fermented meat products or decrease during dry-cured ham ripening. PUT contents increase commonly to 60-140mgkg(-1) in dry spontaneously fermented sausages, however, contents up to several hundreds mgkg(-1) are not extraordinary. Starter cultures are usually able to decrease PUT formation considerably. SPD and SPM contents in dry fermented sausages are comparable with levels typical for fresh meat. Data on SPD and SPM changes during ripening and storage are inconsistent. A decrease of the both polyamines during a storage period has been usually reported.

The complete genome sequence of the meat-borne lactic acid bacterium Lactobacillus sakei 23K

Lactobacillus sakei is a psychotrophic lactic acid bacterium found naturally on fresh meat and fish. This microorganism is widely used in the manufacture of fermented meats and has biotechnological potential in biopreservation and food safety. We have explored the 1,884,661-base-pair (bp) circular chromosome of strain 23K encoding 1,883 predicted genes. Genome sequencing revealed a specialized metabolic repertoire, including purine nucleoside scavenging that may contribute to an ability to successfully compete on raw meat products. Many genes appear responsible for robustness during the rigors of food processing--particularly resilience against changing redox and oxygen levels. Genes potentially responsible for biofilm formation and cellular aggregation that may assist the organism to colonize meat surfaces were also identified. This genome project is an initial step for investigating new biotechnological approaches to meat and fish processing and for exploring fundamental aspects of bacterial adaptation to these specific environments.

Biogenic amines in meat and meat products

It has been recognized for some time that biogenic amines occur in a wide range of foods, among them meat and meat products. Meat is an important component of the diet in developed countries. The presence of these amines in food is of interest for two reasons: firstly, for toxicological reasons, in the sense that high levels of dietary biogenic amines can be toxic for certain consumers, and secondly, for their role as possible quality indicators. Based on these two premises, the present article offers a new analysis on aspects of toxicology and on the use of biogenic amines as a quality control method, as well as on their presence in meat and meat products. The article focuses particularly on factors affecting the production of biogenic amines, with reference to various parameters relating to microorganisms, meat raw materials, and processing conditions. A better understanding of the factors determining their formation (i.e., microorganisms, raw materials used, and technological processes applied) and their effects could lead to ways of controlling their production, limiting their presence in the end product, and hence, rendering them less toxic.

Development of agmatine sensor using the combination of putrescine oxidase and agmatinase for squid freshness

Agmatine (Agm) is an indicator of squid freshness. The Agm sensor was developed using flow injection analysis (FIA) that consisted of the putrescine oxidase (PuOx) reactor, the agmatinase (AUH)-PuOx reactor and two oxygen electrodes. In the proposed sensor, the first step is that coexisting cadaverine (Cad) and putrescine (Put) are removed by passing through the PuOx reactor and the initial decomposition is determined by the amount of oxygen consumed, simultaneously. The second step is that the amount of Agm is determined by the amount of oxygen consumed in the AUH-PuOx reactor. The optimum conditions for the use of the Agm sensor were as follows: 50 mM HEPES containing MnSO4 at a final concentration of 5 mM, pH 8.0, flow rate of 0.6 mL min(-1) and injection volume of 50 microL. A single assay could be completed in approximately 3 min. A linear relationship was obtained between the output and the Agm concentration in the range of 0.01-1 mM Agm with a correlation coefficient of 0.999. The detection limit was 0.005 mM. The relative standard deviations (RSDs) were 3.14 and 1.19% (n = 20) for 0.1 and 0.3 mM Agm, respectively. The extracts of squid were injected into the proposed sensor and the results were compared with those obtained using the conventional high-performance liquid chromatography (HPLC) method. A correlation was observed between the results obtained by the proposed sensor and those obtained by the conventional method. The determination of squid freshness is one of the good uses of the proposed Agm sensor.

Determination of histamine in wines with an on-line pre-column flow derivatization system coupled to high performance liquid chromatography

A new rapid and sensitive high performance liquid chromatography (HPLC) method for determining histamine in red wine samples, based on continuous flow derivatization with 1,2-naphthoquinone-4-sulfonate (NQS), is proposed. In this system, samples are derivatized on-line in a three-channel flow manifold for reagent, buffer and sample. The reaction takes place in a PTFE coil heated at 80 degrees C and with a residence time of 2.9 min. The reaction mixture is injected directly into the chromatographic system, where the histamine derivative is separated from other aminated compounds present in the wine matrix in less than ten minutes. The HPLC procedure involves a C18 column, a binary gradient of 2% acetic acid-methanol as a mobile phase, and UV detection at 305 nm. Analytical parameters of the method are evaluated using red wine samples. The linear range is up to 66.7 mg L(-1) (r = 0.9999), the precision (RSD) is 3%, the detection limit is 0.22 mg L(-1), and the average histamine recovery is 101.5% +/- 6.7%. Commercial red wines from different Spanish regions are analyzed with the proposed method.

Ion-pair high-performance liquid chromatographic determination of biogenic amines and polyamines in wine and other alcoholic beverages

An optimised ion-pair reversed-phase high-performance liquid chromatographic method with automatic o-phthalaldehyde post-column derivatization and spectrofluorometric detection for the same-run separation and quantification of 12 biogenic amines and polyamines in alcoholic beverages has been validated. The reliability of the method was satisfactory in terms of linearity (from 0.5 to 15 mg/l), precision (relative standard deviation below 5%), recovery (from 98.7 to 101.1%), and sensitivity (detection limit between 0.03 and 0.06 mg/l). The automatic accomplishment of the derivatization step reduces time and effort of analysis, especially thanks to the easy preparation of the sample.

Influence of starter and nonstarter on the formation of biogenic amine in goat cheese during ripening

Two commercial starters were investigated for their potential ability to decarboxylate amino acids during goat cheese ripening. Two batches of goat cheese were produced with identical pasteurized milk but different starter cultures. One of them contained Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. cremoris and the other Lactococcus lactis subsp. lactis. The amine contents, microbial counts, proteolysis-related parameters, pH, total solids and salt content were studied in raw materials and cheeses. In raw materials, polyamines were the prevailing amines, whereas the main amines in cheeses were putrescine, tryptamine and, in particular, tyramine (94.59 mg/kg). Aerobic mesophilic microorganisms and Lactococcus counts increased throughout ripening, while Enterobacteriaceae were no longer detectable in cheese after 30 days of ripening. Amine concentration rose during cheese ripening in both batches. Moreover, the decarboxylase activity of microorganisms isolated from samples during cheese ripening was assayed and discussed.

Role of putrescine in cell proliferation in a colon carcinoma cell line

OBJECTIVES

Putrescine, the precursor for higher polyamine biosynthesis, is necessary for cell growth in mammals. Ornithine decarboxylase (ODC) activity and polyamine production are increased in neoplastic cells. Using colon cancer cell line derived from a tumor with high metastatic potential (CT-26), our objective was to study the effect of exogenous putrescine on ODC regulation, polyamine metabolism, and cell proliferation.

METHODS

Cells cultured with fetal calf serum were exposed to 100, 550, and 1000 microM putrescine for 24 h.

RESULTS

Intracellular free putrescine, determined by high-performance liquid chromatography, showed a statistically significant increase in exposed cells compared with controls and a significant correlation with levels of the metabolite present in the medium (r = 0.93; P < 0.001). Bromodeoxyuridine incorporation into newly synthesized DNA, a marker of cell proliferation, showed a statistically significant increase in the three putrescine groups as opposed to the control group. In samples with added aminoguanidine, significant increases in DNA synthesis were observed in the 550- and 1000-microM putrescine groups as opposed to the control group. Spermidine and spermine intracellular contents in all three putrescine-treated groups remained below control levels. No statistical differences in ODC enzymatic activity or ODC mRNA content were observed. Newly incorporated putrescine stimulated colon tumor cell growth.

CONCLUSIONS

Because neither enhanced conversion into the higher polyamines nor aminoguanidine inhibition of proliferation was observed, we suggest that this effect can be attributed to the putrescine molecule itself.

Effect of the interaction between a low tyramine-producing Lactobacillus and proteolytic staphylococci on biogenic amine production during ripening and storage of dry sausages

The interaction between tyrosine-decarboxylase and proteolytic activities of a Lactobacillus curvatus and Staphylococcus xylosus, respectively, on biogenic amine production during the ripening and the storage of dry fermented sausages was investigated. Water content, pH, proteolysis parameters, microbial counts, and biogenic amine contents were monitored in spontaneously and starter fermented sausages. The use of proteolytic staphylococci as starter resulted in a higher content of non-protein nitrogen and total free amino acids. Tyramine was the main amine produced in all batches. However, tyrosine-decarboxylase activity of the L. curvatus starter strain was weak and yielded lower amounts of tyramine than those produced by the wild mioroflora in the control batch. Association between tyramine production and proteolysis could only be established in a defectively dried batch. Putrescine and cadaverine accumulation was efficiently reduced in the starter-mediated fermentation, in agreement with the lower development of enterobacteria. Phenylethylamine and tryptamine were only detected in the spontaneously fermented sausages, while histamine, spermine and spermidine did not vary during the ripening. Biogenic amine levels and related parameters showed significant changes during the storage of dry sausages depending on the temperature and the batch. As a general rule, changes in the pH, proteolysis, microbial counts, and biogenic amine contents were stronger at 19 degrees C than at 4 degrees C. The results suggest that refrigeration would be advisable for preventing further accumulation of biogenic amines during the storage of dry fermented sausages.

Biogenic amines and polyamines in milks and cheeses by ion-pair high performance liquid chromatography

The proposed chromatographic method provides a complete resolution of twelve amines in a single run in milks and unripened cheeses, avoiding the losses of resolution linked to fluctuations in working temperature. We also propose an alternative chromatographic gradient, which can be useful for samples that have undergone long ripening periods, like ripened cheeses. According to the results of the reliability study, the method described was precise, accurate, and sensitive. The method was applied to several samples of milks and cheeses and the results showed that the biogenic amine profiles varied greatly, not only between different types of samples but also among the samples from the same kind of products. In unripened cheeses, milks, and yogurts, spermidine and spermine were the prevailing amines, but in ripened cheeses the major amine was tyramine, followed by putrescine and cadaverine.

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.