Formation Of Biogenic Amines Research Articles

Combined Effect of Sodium Chloride and Clove on Growth and Biogenic Amine Formation of Enterobacter aerogenes in Mackerel Muscle Extract

The inhibitory effects of clove (0.5%) and sodium chloride (1–5%) on the growth and biogenic amine (histamine and cadaverine) production of Enterobacter aerogenes in mackerel muscle broth at 30°C were investigated. At 1% level, sodium chloride was favorable for growth, whereas higher levels slightly reduced the growth in comparison to the control. The maximum population numbers obtained in the presence of sodium chloride were essentially the same as that of the control. Amine production was remarkably enhanced by the presence of 1 % NaCl alone. Only a little increase was observed for higher levels, and sodium chloride at more than 3% had no stimulatory effect on the amine formation. Addition of clove at a level of 0.5% to the broth resulted in a delay in the growth and the amine formation. The presence of NaCl as low as 2% in combination with clove (0.5%) completely inhibited the growth and amine production of E. aerogenes in mackerel broth. Synergistic effects of clove essential oils and sodium chloride could be considered as the probable reason for the inactivation of the bacterium.

The Effect of GDL-induced pH Decrease on the Formation of Biogenic Amines in Meat

The effect of pH on the formation of biogenic amines has mainly been studied in broths in which pH has been fixed before incubation. However, in the fermentation of dry sausage, pH quite rapidly decreases from the initial value to a certain level. In this study glucono-delta-lactone (GDL) was used to decrease pH in meat, Six minced meat samples were each divided into three portions (A–C): 0% (A), 0.5% (B), or 1.0% (C) of GDL was added and the samples were incubated at 20–22°C for 7 d. The amounts of biogenic amines (histamine, tyramine, putrescine, cadaverine, phenylethylamine, tryptamine, spermine, and spermidine) as well as pH, water activity, and the bacterial counts of lactic acid bacteria, fecal streptococci, coliforms, and total plate count were measured. Addition of GDL resulted in a significant decrease in pH and in the levels of histamine and putrescine as well as in the levels of fecal streptococci, coliforms, and total plate counts. Of 87 fecal streptococci, seven Enterococcus faecalis strains produced tyramine. All the coliforms and related strains isolated from violet red bile agar produced tyramine, putrescine, and cadaverine on agar plates. However, the proportion of histamine-positive strains of these strains, especially Hafnia alvei, increased from 0 to 57% during the incubation. The rate and level of pH decrease clearly affected amine formation in meat, indicating that the levels of, e.g., histamine produced could be decreased by optimizing the pH decrease during fermentation. Addition of GDL facilitates study of the effect of pH decrease without interactions between the starter culture and contaminant flora.

Histamine and Tyramine during Storage and Spoilage of Anchovie, Engraulis encrasicholus: Relationships with Other Fish Spoilage Indicators

ABSTRACTThe formation of biogenic amines (histamine and tyramine) during Engraulis encrasicholus storage and spoilage was studied and compared with changes of other fish spoilage indicators: trimethylamine nitrogen, volatile basic nitrogen, hypoxanthine and pH. Good correlations were observed between biogenic amines and the other indicators, at both refrigeration (4–6°C) and room temperature (18–22°C).Two trials were carried out at each temperature. Differences were observed in levels of biogenic amines as well as other indicators in experiments carried out under similar conditions.

Formation of biogenic amines in herring and mackerel.

The formation of biogenic amines (histamine, cadaverine, putrescine and spermidine) was followed during vacuum packed storage at 2 degrees C or 10 degrees C in the scombroid fish mackerel and in the non-scombroid fish herring. Also the changes in the content of free amino acids and in the organoleptic and microbiological qualities were followed. At 10 degrees C the amine contents were 2-20 times higher at the time of rejection as compared with samples stored at 2 degrees C. In herring and mackerel similar amounts of histamine were accumulated, whilst cadaverine was formed at much higher levels in mackerel compared with herring. The high contents of cadaverine in mackerel can possibly explain why mackerel and not herring are often implicated in incidents of scombrotoxic poisoning.

Formation of biogenic amines by isolated kidneys of spontaneously hypertensive rats

Kidneys form dopamine (DA) from L-dopa and serotonin from L-5-hydroxytryptophan (L-5-HTP) via aromatic L-amino acid decarboxylase. We compared the ability of isolated perfused kidneys from adult (20-week-old) spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto rats (WKY) to form these biogenic amines. Renal vascular resistance (RVR) was greater in perfused kidneys from SHR (n = 10) than WKY (n = 8) (p < 0.01). Slight decreases in RVR were observed during L-dopa infusion but these were unrelated to DA formation. L-Dopa infusion was associated with greater DA output in SHR than WKY in both the renal venous and urinary effluents although the latter did not achieve statistical significance. L-5-HTP increased RVR to a greater degree in SHR than WKY kidneys. This was associated with larger quantities of serotonin in the urinary and venous effluents and greater pressor responses to exogenous serotonin in SHR than WKY kidneys; however, either parameter alone was not significantly increased. Our findings do not support a deficiency of intrarenal DA formation as a pathogenic factor for hypertension in SHR. Biogenic amine formation is as great if not greater in SHR than WKY kidneys and appears to contribute largely to the greater increases in renal resistance seen in SHR kidneys on infusion of L-5-HTP. Enhanced renal serotonin formation may elevate blood pressure, whereas enhanced renal DA formation would favor blood pressure lowering, perhaps as a compensatory mechanism.

Identification of Dihydropteridine Reductase in Human Platelets

Normal human platelets were shown to contain the enzyme dihydropteridine reductase. The enzyme was not found in a variety of other cells of hematogenous origin. Partial purification and kinetic and physical data indicated that the platelet enzyme is similar to that previously characterized from liver. Dihydropteridine reductase is important for the regeneration of tetrahydrobiopterin, a required cofactor in hydroxylation reactions involved in biogenic amine formation. The presence of the enzyme may indicate that some synthesis de novo of serotonin and/or catecholamines occurs in platelets, as opposed to a purely storage and transport function. In addition, screening for hyperphenylalaninemia due to dihydropteridine reductase deficiency may become feasible by assaying platelets for enzyme activity.

Identification of dihydropteridine reductase in human platelets

Normal human platelets were shown to contain the enzyme dihydropteridine reductase. The enzyme was not found in a variety of other cells of hematogenous origin. Partial purification and kinetic and physical data indicated that the platelet enzyme is similar to that previously characterized from liver. Dihydropteridine reductase is important for the regeneration of tetrahydrobiopterin, a required cofactor in hydroxylation reactions involved in biogenic amine formation. The presence of the enzyme may indicate that some synthesis de novo of serotonin and/or catecholamines occurs in platelets, as opposed to a purely storage and transport function. In addition, screening for hyperphenylalaninemia due to dihydropteridine reductase deficiency may become feasible by assaying platelets for enzyme activity.

Pathogenesis of phenylketonuria: Inhibition of dopa and catecholamine synthesis in patients with phenylketonuria

Urinary excretion of dopamine, HVA, VMA and MHPG has been studied after oral administration of deuterated l-tyrosine in two patients with PKU, one patient with hyperphenylalaninemia and a normal control at low and high plasma phenylalanine levels by gas chromatography-mass spectrometry. The deuterium content served as an index for the formation of metabolites from the precursor. At a high phenylalanine level the excretion of dopa metabolites was low. When plasma phenylalanine was low a large increase in the amount of urinary metabolites was observed. From these studies it seemed that the tyrosine 3-hydroxylase activity in vivo and thus the formation of L-dopa and other biogenic amines depended on the phenylalanine concentration in plasma and also in tissues.