Biomedical subjects

Mario E Arena

Publications and source records attributed to Mario E Arena.

3 recordsLinked to original sources

PubMed2005

Influence of ethanol and low pH on arginine and citrulline metabolism in lactic acid bacteria from wine.

The aim of this work was to study the effects of ethanol on cell growth and arginine and citrulline metabolism in two heterofermentative lactic acid bacteria from wine, and to determine their possible association with the formation of ethyl carbamate (EC), a carcinogenic compound. Lactobacillus hilgardii X1B is able to utilize arginine and citrulline, while Oenococcus oeni m can only use citrulline, a precursor of EC. Growth of both microorganisms was partially inhibited by 10 and 15% (v/v) ethanol. Specific arginine consumption by L. hilgardii increased when the pH value diminished from 6.5 to 3.8, but was not affected by an increasing ethanol concentration. However, the ethanol concentration affected the specific citrulline consumption of both microorganisms. Arginine metabolism by L. hilgardii X1B increased the amount of citrulline, thus allowing production of EC in the medium. Citrulline utilization by both microorganisms, at all pH values studied, indirectly inhibited the formation of EC; indeed, one of the precursors had practically disappeared after 48 h of incubation. Due to its ability to form precursors, L. hilgardii X1B has the potential to contribute to EC formation, whereas citrulline utilization by O. oeni m in the presence of ethanol may contribute to diminishing the formation of EC. Rapid degradation of citrulline in the presence of ethanol by O. oeni m is important from a toxicological point of view, because it is important to keep the EC levels as low as possible.

Arginine↗

PubMed2004

Differences between biogenic amine detection by HPLC methods using OPA and dansyl derivates.

Biogenic amines can be formed and degraded as a result of normal metabolic activity in animals, plants, and microorganisms and are usually produced by the decarboxylation of amino acids. Recent trends in food security are promoting an increasing search for trace compounds that can affect human health. Although they are present in fermented foods and beverages in low quantities, they exhibit interactions with normal human metabolism (e.g., having vasoactive or psychoactive properties) that justify the research on their presence in foods and the possible related toxicological effects that they may cause. Estimation of the biogenic amines histamine, tyramine, agmatine, putrescine, and cadaverine is important not only from the point of view of their toxicity, but also because they can be used as indicators of the degree of freshness or spoilage of food. Until recently, because of the difficulty in detecting and quantifying amines reliably we have had insufficient information about their occurrence in different types of foods and beverages. These problems are related to matrix interference (e.g., the presence of free amino acids) and the low levels at which the amines are found. Early techniques for the determination of biogenic amines in foods were based on thin-layer chromatography. More modern analytical techniques have since been developed that allow the acquisition of reliable quantitative data and better separation/resolution of various amines. The quantitative determination of biogenic amines is generally accomplished by overpressure-layer chromatography, high-performance liquid chromatography (HPLC), and gas chromatography. The use of reverse-phase column and precolumn derivatization was more efficient and faster than the conventional ion-exchange techniques. This study was conducted to evaluate two HPLC derivatization methods for quantitative determination of biogenic amines: the method described by Gonzales de Llano et al. for amino acid analysis and the method described by Eerola et al.

Biogenic Amines↗

PubMed2002

Comparative survey in Lactobacillus plantarum of the growth and metabolism of arginine and citrulline in different media.

Arginine deiminase activity increased in the presence of arginine in Lactobacillus plantarum strains N4 and N8 isolated from orange. The influence of citrulline and ornithine on arginine deiminase and ornithine transcarbamylase activities was strain-dependent. The growth and arginine and citrulline metabolism of L. plantarum were studied in the presence of tomato juice. Its addition enhances the growth in both strains. The specific amino acids utilization was inversely proportional to the initial glucose concentration. Arginine and citrulline addition to basal medium exerted a stimulatory effect on the growth of N4 strain, and this effect was observed only with citrulline in strain N8. The magnitude of this effect was lower in the presence of tomato juice.

Arginine↗