Formation Of Tyramine Research Articles

Comparison of the formation of biogenic amines in irradiated and smoked fish

Levels of eight biogenic amines (putrescine, cadaverine, spermidine, spermine, histamine, tyramine, tryptamine and phenylethylamine) were determined in vacuum-packed fillets of grass carp (Ctenopharyngodon idella) and bighead carp (Hypophthalmichthys molitrix). Fish flesh was treated by high-energy electron beam irradiation at low doses of 0.25 and 0.50 kGy or by smoking. The control and treated packs were stored at 3.5 °C for up to 70 days (irradiated) and for 181 days (smoked). Tyramine content was the most sensitive indicator of the improper status of samples, levels exceeding 10 mg/kg indicated the loss of meat freshness, in spite of persisting good sensory indices. Irradiation prolonged the shelf-life of samples 4–5 times, smoking was more effective. The formation of tyramine, putrescine and cadaverine fitted well the Gompertz model.

Formation of tyramine in yoghurt during fermentation – Interaction between yoghurt starter bacteria and Lactobacillus plantarum

This study aimed to investigate the formation of tyramine during yoghurt fermentation with the focus on interaction between Streptococcus thermophilus RSKK 04082, Lactobacillus delbrueckii subsp. bulgaricus DSM 20081 and Lactobacillus plantarum RSKK 02030. These microorganisms were used in the yoghurt fermentation as single strains or mixed cultures containing double or triple strains. The interactions between microorganisms have been also revealed by determining total free amino acids and the pH of the medium together with the microbial count of the strains. It was observed that L. delbrueckii subsp. bulgaricus DSM 20081 did not produce tyramine while S. thermophilus RSKK 04082 and L. plantarum RSKK 02030 could produce tyramine depending on the fermentation conditions. Synergistic interactions between S. thermophilus RSKK 04082 and L. delbrueckii subsp. bulgaricus DSM 20081 and, between L. delbrueckii subsp. bulgaricus DSM 20081 and L. plantarum RSKK 02030 were found in terms of tyramine production. It was observed in this study that L. delbrueckii subsp. bulgaricus DSM 20081 had indirect effect on accumulation of tyramine in the yoghurts.

Quality of monosex tilapia under ice storage: Gutting effects on the formation of biogenic amines, biochemical, and microbiological characteristics

ABSTRACTEffects of gutting on biogenic amine (putrescine, cadaverine, histamine, agmatine, tyramine, spermidine, and spermine) formation, biochemical (pH, TVBN, K value), microbial (APC, H2S producing, Coliform bacteria), and sensory quality of farmed monosex tilapia (Oreochromis niloticus) was studied during ice stored at 4 ± 2ºC. Spermine and spermidine levels were high with cadaverine reached 4.66 ppm in gutted sample. The other amines were detected at relatively low level. K value of both samples crossed 60% on 15th and 18th day, respectively. The total phenolic content exceeded 7 log cfu/g after sensory rejection. The shelf life of whole and gutted samples was estimated to be 24 and 21 days, respectively.

Effect of Sugar on the Changes in Quality of Lightly Salted Grass Carp (Ctenopharyngodon idellus) Fillets under Vacuum Packaging at 4°C

To estimate the effect of a low concentration of sugar on the changes in quality of lightly salted grass carp (Ctenopharyngodon idellus) during storage under vacuum packaging at 4°C, we determined the sensory score, total viable counts, biochemical quality, and physical quality of fish fillets. Fish samples were left untreated, dry cured with 1.3% salt, or dry cured with 1.3% salt plus 1.0% sugar. Compared with untreated samples, curing treatments reduced chemical changes reflected in pH, inosine monophosphate, hypoxanthine riboside, hypoxanthine, and total volatile base nitrogen; decreased the formation of phenylethylamine, putrescine, cadaverine, and histamine; and increased the overall sensory quality of fillets (P < 0.05). Compared to dry cured with 1.3% salt samples, sugar treatment significantly inhibited (P < 0.05) the increase in pH and total volatile base nitrogen value, but it promoted microbial growth and the formation of phenylethylamine and tyramine at later stages of storage. By considering each indicator, the addition of sugar, which can improve the taste of fillets, has no significant effect on the shelf life of vacuum-packaged grass carp fillets.

Reduction of Cadaverine and Tyramine Formation by Proteolytic Enzymes in Model System

Cadaverine and tyramine are biogenic amines that are commenly found in fermented foods. This study focused on the reduction of cadaverine and tyramine formation by a new method using proteolytic enzymes (trypsin and chymotrypsin). Cadaverine and tyramine were synthesized from lysine and tyrosine in the presence of their decarboxylase enzymes, respectively. In this study, trypsin and chymotrypsin were used separately or in combination to reduce formation of cadaverine and tyramine in model system. Tyramine synthesis was reduced by trypsin and chymotrypsin as 57.2 and 52.1%, respectively. Moreover, the reduction of cadaverine was 80.4 and 83.0% by trypsin and chymotrypsin, respectively. Maximum reduction values were obtained when trypsin and chymotrypsin were used together for the reduction of tyramine (59.1%) and cadaverine formation (84.8%). In model system, cadaverine and tyramine formation were (p < 0.05) significantly reduced. It was concluded that trypsin and chymotrpsin could be used to reduce tyramine and cadaverine formation.

Effects of plant polyphenols and α-tocopherol on lipid oxidation, microbiological characteristics, and biogenic amines formation in dry-cured bacons.

Effects of plant polyphenols (tea polyphenol [TP], grape seed extract [GSE], and gingerol) and α-tocopherol on physicochemical parameters, microbiological counts, and biogenic amines were determined in dry-cured bacons at the end of ripening. Results showed that plant polyphenols and α-tocopherol significantly decreased pH, thiobarbituric acid reactive substances content, and total volatile basic nitrogen (TVBN) compared with the control (P < 0.05). Microbial counts and biogenic amine contents in dry-cured bacons were affected by plant polyphenols or α-tocopherol, with TP being the most effective (P < 0.05) in reducing aerobic plate counts, Enterobacteriaceae, Micrococcaceae, yeast, and molds, as well as in inhibiting formation of putrescine, cadaverine, tyramine, and spermine. Principal component analysis indicated that the first 2 principal components (PC) explained about 85.5% of the total variation. PC1 was related with physicochemical factors, parts of biogenic amines, and spoilage microorganisms, whereas PC2 grouped the TVBN, tyramine, 2-phenylethylamine, yeast, and molds. These findings suggest that plant polyphenols, especially TP, could be used to process dry-cured bacons to improve the quality and safety of finished products.

Suppression of the formation of biogenic amines in mackerel mince by microbial transglutaminase.

Microbial transglutaminase (MTGase) is an enzyme utilized in the food industry in many areas. In this study, the suppression effect of MTGase at various levels (0, 2, 5, 10 g kg(-1)) on the formation of biogenic amines in mackerel was determined during refrigerated storage of 8 days. Mince added with 2 g kg(-1) MTGase showed the lowest formation of putrescine, cadaverine and tyramine throughout the storage. Histamine exceeded the consumable limit (500 mg kg(-1) ) after the 4th day, except for that containing 2 g kg(-1) MTGase. The formation of total volatile basic nitrogen and total free amino acid content were retarded and the pH value was unaltered by addition of MTGase. With increasing MTGase levels, the growth of total psychrophilic bacteria, mould, yeast and coliform bacteria was retarded. The sensory scores of mackerel mince increased as MTGase concentrations increased. MTGase plays a role in maintaining the quality of mackerel mince during refrigerated storage. As a result of the present study, a new use for MTGase in the food industry is revealed. It will contribute especially in the field of development of products for consumers with allergic sensitivity.

Effects of Modified Atmosphere Packaging with Various Carbon Dioxide Composition on Biogenic Amines Formation in Indian Mackerel (Rastrelliger kanagurta ) stored at 5 ± 1°C

The profile of major biogenic amines was investigated in Indian mackerel packed in modified atmosphere for up to 12 days at 5 ± 1°C. Beheaded and gutted Indian mackerel was packed under different carbon dioxide compositions to study the effects on biogenic amines formation. The treatments were control air (C), vacuum packaging (VP), 30% CO2/65% N2/5% O2 (M30C), 60% CO2/35% N2/5% O2 (M60C), 80% CO2/15% N2/5% O2 (M80C) and 100% CO2 (M100C). Each amine responded differently to different CO2 levels. After 12 days of storage, concentrations of histamine were reduced by 6.4%, 8.5%, 70.3%, 78.8% and 90.2% in fish packed under VP, M30C, M60C, M80C and M100C, respectively as compared with control air. Changes in putrescine and cadaverine showed a similar pattern. Gas mix of M30C and VP stimulated the formation of tyramine reaching 203 and 172 ppm, respectively. Higher composition of CO2 had a significant inhibitory effect on tyramine concentration (p 0.05). After 9 days of storage, more than 300 ppm of histamine was detected in mackerel packed in VP and M30C; therefore, these atmospheres pose a histamine intoxication risk. Copyright © 2013 John Wiley & Sons, Ltd.

Tyramine and Phenylethylamine Biosynthesis by Food Bacteria

Tyramine poisoning is caused by the ingestion of food containing high levels of tyramine, a biogenic amine. Any foods containing free tyrosine are subject to tyramine formation if poor sanitation and low quality foods are used or if the food is subject to temperature abuse or extended storage time. Tyramine is generated by decarboxylation of the tyrosine through tyrosine decarboxylase (TDC) enzymes derived from the bacteria present in the food. Bacterial TDC have been only unequivocally identified and characterized in Gram-positive bacteria, especially in lactic acid bacteria. Pyridoxal phosphate (PLP)-dependent TDC encoding genes (tyrDC) appeared flanked by a similar genetic organization in several species of lactic acid bacteria, suggesting a common origin by a single mobile genetic element. Bacterial TDC are also able to decarboxylate phenylalanine to produce phenylethylamine (PEA), another biogenic amine. The molecular knowledge of the genes involved in tyramine production has led to the development of molecular methods for the detection of bacteria able to produce tyramine and PEA. These rapid and simple methods could be used for the analysis of the ability to form tyramine by bacteria in order to evaluate the potential risk of tyramine biosynthesis in food products.

Elaboration of Tempranillo wines at two different pHs. Influence on biogenic amine contents

The aim of this work was to study the effect of pH on biogenic amine formation during the elaboration and conservation (7 months) of Tempranillo wines. Grapes at two pHs (3.4 and 3.7) were vinified to achieve this purpose. After alcoholic fermentation the wines were either inoculated with a commercial malolactic starter or not inoculated. Identification and clonal distribution of lactic acid bacteria and amino acid concentration were determined in an attempt to explain the biogenic amine generation. The results showed that the pH of the must influenced the clonal distribution of the Oenococcus oeni strains which conducted the malolactic fermentation and also the concentration of amino acids in the wines after alcoholic fermentation. These aspects could account for the higher biogenic amine formation in wines with the lowest pH during malolactic fermentation. In these wines, inoculation with a malolactic starter was favourable since it produced a lower biogenic amine concentration after malolactic fermentation. Furthermore, the pH also influenced the concentration of amino acids after malolactic fermentation and the lactic acid bacteria distribution during the conservation of the wines. These aspects allow explaining the greater formation of histamine, tyramine and putrescine in the wines with the lowest pH vinified via lactic acid bacteria inoculation after seven months of conservation.

Screening selected strains of probiotic lactic acid bacteria for their ability to produce biogenic amines (histamine and tyramine)

SummaryThe aim of this study was to investigate the production of biogenic amines (BA), histamine and tyramine by some probiotic lactic acid bacteria (LAB). Fifteen strains representing six LAB species were screened qualitatively by growing them in a decarboxylase medium. Quantitative analysis was carried out by HPLC analysis with direct derivatization of acid extracts. Lactobacillus casei (TISTR 389) and Lactobacillus delbrueckii subsp. bulgaricus (TISTR 895) were found to produce BA. The highest levels of histamine (1820.9 ± 3.5 mg L−1) and tyramine (5486.99 ± 47.6 mg L−1) formation were observed for the TISTR 389 strain, while TISTR 895 produced only histamine (459.1 ± 0.63 mg L−1) in the decarboxylase broth. Biogenic amine potential was not observed for the Lactobacillus acidophilus, Lactobacillus lactis subsp. lactis, Lactococcus lactis subsp. lactis, and Lactobacillus plantarum strains studied. This study confirmed that BA formation is strain dependent and not related to the species. Therefore, careful screening for amino acid decarboxylase activity is recommended before selecting LAB as appropriate starter or probiotic strains in food and dairy industry.

Biogenic amines in carp roe (Cyprinus carpio) preserved by four different methods

Carp roe (Cyprinus carpio) was pasteurised, salted, smoked and treated by a lactic acid based preservative agent. Chemical and sensory qualities were measured throughout the storage time to determine the changes that took place at 2°C and to evaluate the effects of the preservation method. Seven biogenic amines (putrescine, cadaverine, spermidine, spermine, histamine, tyramine and tryptamine) were determined. Cadaverine showed very good correspondence with the sensory markers of the samples. Samples of good quality contained less than 5mg/kg of cadaverine. Histamine and tyramine did not exceed the value of 5 and 25mg/kg, respectively, for samples with good organoleptic properties. The formation of tyramine was effectively prevented by salting. After comparing the methods of preservation, pasteurisation and smoking were determined as the most efficient.

Formation of cadaverine, histamine, putrescine and tyramine by bacteria isolated from meat, fermented sausages and cheeses

Enterobacteriaceae (EB, n = 149), Lactobacillus (LB, n = 162) and Leuconostoc sp. (LC, n = 89) and enterococci (EC, n = 137), isolated from raw meat (n = 65), fermented sausages (n = 50) and cheese (n = 55) samples, were cultivated in a broth containing precursor amino acids (each 3 g/l). After incubation, the liquid culture was chemically analysed for cadaverine (CAD), putrescine (PUT), histamine (HIS) and tyramine (TYR) formation at pH 5.2 and at pH 6.7. The majority of EB isolates (147 of 149) was capable of forming >100 mg/l of either CAD or PUT. Among the most frequently isolated species Hafnia alvei and Serratia liquefaciens, formation of >100 mg/l HIS occurred, but with low prevalence (1.6 and 6.5%, respectively). Twelve of 149 isolates (8%) were able to produce more than 10 mg/l HIS. One hundred forty-two isolates (95.3%) produced less than 10 mg/l TYR, and 7 isolates (4.7%) 10 mg/l to a maximum of 35.3 mg/l TYR. For LB + LC, one isolate (Leuconostoc mesenteroides ssp. mesenteroides) formed >100 mg/l PUT and one >100 mg/l CAD (of all 251 LB + LC isolates 0.4% each). Formation of >100 mg/l HIS and TYR was detected in 3.6 and 19% of the LB + LC isolates, respectively. For the EC isolates, maximum levels for PUT, CAD and HIS were 25.4 mg/l, 6.0 mg/l and 15.7 mg/l, respectively. TYR was formed in quantities of 100–1000 mg/l by 47.9% of EC faecalis (n = 75), and 59.7% of EC faecium (n = 62) isolates. More than 1000 mg/l TYR were formed by 50.7 and 35.5% of the isolates, respectively. A low initial pH of 5.2 compared to the initial pH of 6.7 favoured tyramine production by lactic acid bacteria, but was associated with lower CAD yield by EB.

Some characteristics of commercial Som-fug produced in Thailand

Seven commercial brands of Som-fug were analysed for chemical composition, biogenic amines and acceptance. Commercial Som-fug contained 11.4–16.2% protein, 1.13–1.56% lipid, 69.66–77.08% moisture, 2.45–3.60% ash and 3.37–4.90% salt. The pH values ranged from 4.56 to 4.60 and total acidity varied from 1.42% to 2.35%. Lactic acid was the major organic acid in all samples, but citric acid, succinic acid and pyruvic acid were found only in some brands. Differences in the trichloroacetic acid soluble peptides and lipid oxidation, among all samples, were observed. The proteolysis of myosin heavy chain was observed on SDS–PAGE analysis. Additionally, the formation of biogenic amines, including tryptamine, putrescine, cadaverine, histamine and tyramine, was observed in commercial Som-fug, but β-phenylethylamine was not detectable in any samples. Different Som-fug samples showed different acceptabilities, especially for taste and appearance. Therefore, raw materials, ingredients and process should be factors for determining the characteristics of Som-fug products.

Biogenic Amine Formation and “Zapatera” Spoilage of Fermented Green Olives: Effect of Storage Temperature and Debittering Process

The effects of temperature and the debittering process on amine formation and other chemical changes related to “zapatera” spoilage of fermented green table olives during storage, without any chemical correction, were studied. Unwashed olive brines were more concentrated in all analyzed compounds, except NaCl. No changes in formic, acetic, and succinic acids or in ethanol, hydroxytyrosol, or tyrosol were observed in the olive brines during storage. The concentration of putrescine in the brine at the beginning of storage and end of fermentation was about 38 mg/liter, and it did not change during storage. This amine only seems to be produced during the active fermentation phase. The effects of temperature and the type of debittering process and time and its interactions (except the time × temperature × debittering process on pH) had signi cant effects on the production of cadaverine and tyramine, as well as on changes of pH and lactic and propionic acids. Storage at 15°C produced a complete stabilization of the fermented olives. However, storage of washed olives at 20 and 28°C produced a gradual decrease of lactic acid content, an increase in pH, production of propionic acid, and formation of cadaverine and tyramine, the effect becoming greater as the temperature rose. It appears that formation of cadaverine and tyramine only occurs during storage and might be related to zapatera spoilage. Changes were always significantly lower in unwashed olives, which leads to a practical stabilization of the product.

Application of lactic acid bacteria starter cultures for decreasing the biogenic amine levels in sauerkraut

Sauerkrauts from shredded white cabbage of six varieties were prepared in six laboratory experiments by initial fermentation at 22 °C for 14 days, then stored at 5–6 °C and analysed after 6 months. Seven biogenic amines were extracted with perchloric acid and determined as N-benzamides by micellar electrokinetic capillary chromatography. Eight common sauerkraut quality parameters were also determined. In three experiments, a commercial strain of Lactobacillus plantarum and a mixed preparation of Microsil containing L. plantarum, Lactobacillus casei, Enterococcus faecium and Pediococcus pentosaceus, were applied at doses of 5×104, 1×105 and 5×105 CFU/g of cabbage. In three further experiments, L. plantarum, Microsil and a commercial strain of Lactobacillus buchneri were applied at doses of 5×105 and 5×106 CFU/g. Spontaneously fermented sauerkrauts were prepared as the control variants in all experiments. L. plantarum at doses of at least 5×105 CFU/g significantly (P<0.05) suppressed formation of putrescine, tyramine and cadaverine, amines occurring at the highest levels. Spermidine contents varied between 10 and 30 mg/kg and were not affected by the starter cultures. Levels of tryptamine, spermine and histamine were very low, often below the detection limits. For practical application, a dose of at least 5×106 CFU/g of the tested L. plantarum strain seems to be likely. The tested strains of L. buchneri and E. faecium showed tyrosine decarboxylase activity in an in vitro test.

Biogenic amine formation in bottled beer

Formation of six biogenic amines in bottled beers was investigated in seven laboratory experiments. Amines were determined as N-benzamides by micellar electrokinetic capillary chromatography. Formation of amines, during the initial 8-day storage of bottled beers from three breweries at 21 °C was very limited. However, statistically highly significant tyramine formation was observed in one experiment during 12-weeks’ storage. Considerable increases of tyramine and to a lesser extent of histamine levels, were found in beers inoculated with mixed cultures of brewery lactic acid bacteria and stored until haze formation. Lactobacilli were much more effective amine producers than pediococci. Limited increases of putrescine and spermidine levels were observed only sporadically. Cadaverine contents were not affected; tryptamine levels were below the detection limit. Thus, tyramine and histamine levels can increase considerably in insufficiently pasteurised bottled beers.

ALKALOID BIOSYNTHESIS IN PLANTS: Biochemistry, Cell Biology, Molecular Regulation, and Metabolic Engineering Applications.

Recent advances in the cell, developmental, and molecular biology of alkaloid biosynthesis have heightened our appreciation for the complexity and importance of plant secondary pathways. Several biosynthetic genes involved in the formation of tropane, benzylisoquinoline, and terpenoid indole alkaloids have now been isolated. The early events of signal perception, the pathways of signal transduction, and the function of gene promoters have been studied in relation to the regulation of alkaloid metabolism. Enzymes involved in alkaloid biosynthesis are associated with diverse subcellular compartments including the cytosol, vacuole, tonoplast membrane, endoplasmic reticulum, chloroplast stroma, thylakoid membranes, and perhaps unique "biosynthetic" or transport vesicles. Localization studies have shown that sequential alkaloid biosynthetic enzymes can also occur in distinct cell types, suggesting the intercellular transport of pathway intermediates. Isolated genes have also been used to genetically alter the accumulation of specific alkaloids and other plant secondary metabolites. Metabolic modifications include increased indole alkaloid levels, altered tropane alkaloid accumulation, elevated serotonin synthesis, reduced indole glucosinolate production, redirected shikimate metabolism, and increased cell wall-bound tyramine formation. This review discusses the biochemistry, cell biology, molecular regulation, and metabolic engineering of alkaloid biosynthesis in plants.

Effect of tyrosine on tyramine formation during beer fermentation

Changes in tyramine, in its precursor amino acid tyrosine, and in Pediococcus spp. were followed during 54 beer fermentations. No statistical relationship between tyramine production and wort tyrosine levels was found, either between the amount of tyramine formed or the decrease in tyrosine through beer fermentation. However, tyramine formation significantly correlated with Pediococcus spp. contamination (r=0.876; P<0.001, n=54). Higher initial tyrosine levels did not induce greater tyramine formation when a similar degree of contamination by Pediococcus spp. occurred, either between tyrosine decrease and tyramine formation. Special attention is required in controlling the presence of lactic acid bacteria to minimise the formation of tyramine. However, the amount of tyrosine does not seem to be a critical factor in the tyramine formation during beer fermentation.

The effects of lactic acid bacteria inoculants on biogenic amines formation in sauerkraut

Sauerkrauts were prepared in three laboratory experiments from three white cabbage varieties by initial fermentation at 22°C for 14 days, then stored at 5–6°C and analysed after six months. Six variants were observed: a spontaneously fermented one as control and inoculated ones with commercial strains of lactic acid bacteria Lactobacillus plantarum, Lactobacillus casei, Pediococcus pentosaceus, Enterococcus faecium and mixed Microsil preparative, all at dose 5×106 CFU g−1 of cabbage. Seven biogenic amines were extracted with perchloric acid and determined as N-benzamides by micellar electrokinetic capillary chromatography. Sauerkraut quality parameters, pH value, total acidity, lactic acid, acetic acid, ammonia, alpha-amino groups and ethanol, were also determined. Histamine, tryptamine, spermidine and spermine concentrations were usually below 10 mg kg−1 and sometimes below detection limits. Formation of tyramine, putrescine and cadaverine, whose total concentrations were from 450 to 780 mg kg−1 in control variants, was significantly (P<0.005) suppressed by L. plantarum and Microsil. Similarly, these inoculants also significantly lowered (P<0.005) formation of acetic acid, ammonia and alpha-amino groups. The effects of the other inoculants were limited.