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M. Pidoux - One of the best experts on this subject based on the ideXlab platform.
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Characterization of interactions between Lactobacillus hilgardii and Saccharomyces florentinus isolated from sugary kefir grains
Journal of Applied Bacteriology, 1993Co-Authors: Françoise Leroi, M. PidouxAbstract:Stimulation of the growth of Lactobacillus hilgardii and production of lactic acid in the presence of Saccharomyces florentinus have already been observed in a poor glucose medium. In this study we showed that CO2, pyruvate, propionate, acetate and succinate excreted by the yeast were responsible for this phenomenon, whereas ethanol, fumarate and a cocktail of vitamins had no effect. Fermentation by the yeast did not enrich the total nitrogen or free amino acid content of the medium. The use of proteases confirmed that it was improbable that any nitrogenous compound could be responsible for the bacterial activation. Between values of 0.1 and 5%, the initial yeast: bacteria ratio had no effect on the stimulation of Lact. hilgardii, even though yeast fermentation was drastically affected by a low initial value. The interactions differed greatly according to the sugar source. With monosaccharides, stimulation began after 48 h of culture, and was higher on glucose than on fructose. With sucrose, stimulation appeared at the beginning of fermentation. Different mechanisms seemed to be involved.
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Detection of interactions between yeasts and lactic acid bacteria isolated from sugary kefir grains
Journal of Applied Bacteriology, 1993Co-Authors: Françoise Leroi, M. PidouxAbstract:Different techniques were tested for studying the synergism between the micro-organisms of sugary kefir grains. Agar cultures in Petri dishes did not give reproducible results. In sequential cultures, i.e. growing one organism, sterile filtering and then inoculating the other, 10 of 18 selected lactic acid bacteria/yeast pairs revealed stimulation of bacterial growth in a poor glucose medium. In mixed culture, Saccharomyces florentinus supported better survival of Lactobacillus hilgardii and a significant increase in lactic acid production; at the same time, the growth and alcoholic fermentation of S. florentinus were drastically reduced. The inter-relationships between these two strains were the same when immobilized in calcium alginate beads, even though total metabolite production was always lower than with free cells. The stimulation of Lact. hilgardii by Candida lambica in sequential culture was not confirmed in mixed culture, where the two organisms grew as in pure culture, and bacterial growth and lactic acid production were inhibited in the immobilized system.
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Growth performances ofLactobacillus hilgardii immobilized in dextran gel and in continuous fermentation
World Journal of Microbiology and Biotechnology, 1992Co-Authors: M. Pidoux, M. F. Pilet, V. RipocheAbstract:A variant of Lactobacillus hilgardii was immobilized by its own production of dextran gel, forming grains. The best rate of weight increase of the gel in continuous fermentation was 16.3±3.3%/h, at pH 4.8±0.1 and with a dilution rate of 0.22 to 0.26/h. Observation by scanning electron microscopy located most of the bacteria as microcolonies on the surface. A similar arrangement appeared in calcium alginate beads. The best population density (10^10 cells/g) was obtained in grains at pH 5.8, after 30h. At a similar pH value, 4.8, the growth rate was higher in alginate beads than in dextran gel but the final population density was approximately the same. Acidification rate increased faster with mixed gel at pH 5.2 than with dextran at pH 5.8.
Françoise Leroi - One of the best experts on this subject based on the ideXlab platform.
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Influence of pH, temperature and initial yeast : bacteria ratio on the stimulation of Lactobacillus hilgardii by Saccharomyces florentinus isolated from sugary kefir grains
The Journal of applied bacteriology, 1996Co-Authors: Françoise Leroi, P. CourcouxAbstract:The effects of pH, temperature and initial yeast : bacteria ratio on Lactobacillus hilgardii and Saccharomyces florentinus cultivated either in pure or mixed culture were studied. Quadratic polynomial as a function of factors was proposed to express the lactic acid production at different sampling times, and the percentage increase in lactic acid production by Lact. hilgardii in mixed culture compared with pure culture. Temperature was the factor which had the main influence on lactic acid production in mixed culture, whereas stimulation of bacteria depended greatly on pH value. In the range 0.1-20%, the initial yeast : bacteria ratio had no effect on these responses, but presence of the yeast was absolutely necessary to obtain high production of lactic acid. Optimum culture conditions were determined to maximize these characteristics.
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Characterization of interactions between Lactobacillus hilgardii and Saccharomyces florentinus isolated from sugary kefir grains
Journal of Applied Bacteriology, 1993Co-Authors: Françoise Leroi, M. PidouxAbstract:Stimulation of the growth of Lactobacillus hilgardii and production of lactic acid in the presence of Saccharomyces florentinus have already been observed in a poor glucose medium. In this study we showed that CO2, pyruvate, propionate, acetate and succinate excreted by the yeast were responsible for this phenomenon, whereas ethanol, fumarate and a cocktail of vitamins had no effect. Fermentation by the yeast did not enrich the total nitrogen or free amino acid content of the medium. The use of proteases confirmed that it was improbable that any nitrogenous compound could be responsible for the bacterial activation. Between values of 0.1 and 5%, the initial yeast: bacteria ratio had no effect on the stimulation of Lact. hilgardii, even though yeast fermentation was drastically affected by a low initial value. The interactions differed greatly according to the sugar source. With monosaccharides, stimulation began after 48 h of culture, and was higher on glucose than on fructose. With sucrose, stimulation appeared at the beginning of fermentation. Different mechanisms seemed to be involved.
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Detection of interactions between yeasts and lactic acid bacteria isolated from sugary kefir grains
Journal of Applied Bacteriology, 1993Co-Authors: Françoise Leroi, M. PidouxAbstract:Different techniques were tested for studying the synergism between the micro-organisms of sugary kefir grains. Agar cultures in Petri dishes did not give reproducible results. In sequential cultures, i.e. growing one organism, sterile filtering and then inoculating the other, 10 of 18 selected lactic acid bacteria/yeast pairs revealed stimulation of bacterial growth in a poor glucose medium. In mixed culture, Saccharomyces florentinus supported better survival of Lactobacillus hilgardii and a significant increase in lactic acid production; at the same time, the growth and alcoholic fermentation of S. florentinus were drastically reduced. The inter-relationships between these two strains were the same when immobilized in calcium alginate beads, even though total metabolite production was always lower than with free cells. The stimulation of Lact. hilgardii by Candida lambica in sequential culture was not confirmed in mixed culture, where the two organisms grew as in pure culture, and bacterial growth and lactic acid production were inhibited in the immobilized system.
Tim Hogg - One of the best experts on this subject based on the ideXlab platform.
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Activity of lysozyme on Lactobacillus hilgardii strains isolated from Port wine.
Food Microbiology, 2015Co-Authors: Rita Dias, Eduardo Vilas-boas, Francisco M. Campos, Tim Hogg, José António CoutoAbstract:This work evaluated the effect of lysozyme on lactobacilli isolated from Port wine. Bacterial growth experiments were conducted in MRS/TJ medium and inactivation studies were performed in phosphate buffer (KH2PO4), distilled water and wine supplemented with different concentrations of lysozyme. The response of bacteria to lysozyme was found to be highly strain dependent. Some strains of Lactobacillus hilgardii together with Lactobacillus collinoides and Lactobacillus fructivorans were found to be resistant to concentrations of lysozyme as high as 2000 mg/L. It was observed that among the L. hilgardii taxon the resistant strains possess an S-layer coat. Apparently, the strains of L. collinoides and L. fructivorans studied are also S-layer producers as suggested by the total protein profile obtained by SDS-PAGE. Thus, the hypothetical protective role of the S-layer against the action of lysozyme was investigated. From the various treatments used to remove the protein from the surface of the cells, the one employing LiCl (5 M) was the most effective. LiCl pre-treated cells exposed to lysozyme (2000 mg/L) in KH2PO4 buffer maintained its resistance. However, when cells were suspended in distilled water an increased sensitivity to lysozyme was observed. Moreover, it was found that the addition of ethanol (20% v/v) to the suspension medium (distilled water) triggered a strong inactivation effect especially on cells previously treated with LiCl (reduction of >6 CFU log cycles). The results suggest that the S-layer exerts a protective effect against lysozyme and that the cell suspension medium influences the bacteriolysis efficiency. It was also noted that ethanol enhances the inactivation effect of lysozyme.
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Effect of phenolic aldehydes and flavonoids on growth and inactivation of Oenococcus oeni and Lactobacillus hilgardii.
Food microbiology, 2007Co-Authors: Ana R. Figueiredo, Francisco M. Campos, Tim Hogg, Victor De Freitas, José António CoutoAbstract:The aim of this work was to investigate the effect of wine phenolic aldehydes, flavonoids and tannins on growth and viability of strains of Oenococcus oeni and Lactobacillus hilgardii. Cultures were grown in ethanol-containing MRS/TJ medium supplemented with different concentrations of phenolic aldehydes or flavonoids and monitored spectrophotometrically. The effect of tannins was evaluated by monitoring the progressive inactivation of cells in ethanol-containing phosphate buffer supplemented with grape seed extracts with different molecular weight tannins. Of the phenolic aldehydes tested, sinapaldehyde, coniferaldehyde, p-hydroxybenzaldehyde, 3,4-dihydroxybenzaldehyde and 3,4,5-trihydroxybenzaldehyde significantly inhibited the growth of O. oeni VF, while vanillin and syringaldehyde had no effect at the concentrations tested. Lact. hilgardii 5 was only inhibited by sinapaldehyde and coniferaldehyde. Among the flavonoids, quercetin and kaempferol exerted an inhibitory effect especially on O. oeni VF. Myricetin and the flavan-3-ols studied (catechin and epicatechin) did not affect considerably the growth of both strains. Condensed tannins (particularly tetramers and pentamers) were found to strongly affect cell viability, especially in the case of O. oeni VF. In general, this strain was found to be more sensitive than Lact. hilgardii 5 to the phenolic compounds studied. This work contributes to the knowledge of the effect of different phenolic compounds on the activity of wine lactic acid bacteria, which, especially in the case of aldehydes and of different molecular weight fractions of tannins, is very scarce.
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Effect of phenolic acids on glucose and malic acid metabolism of Lactobacillus hilgardii
2003Co-Authors: Francisco M. Campos, José António Couto, Tim HoggAbstract:Four phenolic acids that occur naturally in wine (p-coumaric, caffeic, ferulic and protocatechuic acids), which were previously found to affect growth of Lactobacillus hilgardii, were tested for their effects on glucose and malic acid metabolism by this bacteria. Growth experiments were performed in modified MRS medium supplemented with phenolic acids. Bacterial growth was monitored spectrophotometrically and the medium glucose and organic acids (citric, malic, lactic and acetic) concentrations were determined by HPLC-UV-IR. Experimental results obtained indicated that all tested phenolic acids caused a decrease in malolactic fermentation rate. Ferulic and caffeic acids reduced both the malolactic fermentation and acetic acid production rates, and increased the final cell density. p-Coumaric acid had an inhibitory effect on growth, thereby affecting malolactic fermentation. Glucose metabolism was not significatively affected by the presence of phenolic acids in the growth medium, except for p-coumaric acid.
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Influence of phenolic acids on growth and inactivation of Oenococcus oeni and Lactobacillus hilgardii
Journal of applied microbiology, 2003Co-Authors: Francisco M. Campos, José António Couto, Tim HoggAbstract:F.M. C AMPOS, J .A. C OUTO A ND T .A. H OGG. 2003. Aims: To determine the effect of several wine-associated, phenolic acids on the growth and viability of strains of Oenococcus oeni and Lactobacillus hilgardii. Methods and Results: Growth was monitored in ethanol-containing medium supplemented with varying concentrations of hydroxybenzoic acids (p-hydroxybenzoic, protocatechuic, gallic, vanillic and syringic acids) and hydroxycinnamic acids (p-coumaric, caffeic and ferulic acids). Progressive inactivation was monitored in ethanolcontaining phosphate buffer supplemented in a similar manner to the growth experiments. Hydroxycinnamic acids proved to be more inhibitory to the growth of O. oeni than hydroxybenzoic acids. On the other hand, some acids showed a beneficial effect on growth of Lact. hilgardii. p-Coumaric acid showed the strongest inhibitory effect on growth and survival of both bacteria. Conclusions: Most phenolic acids had a negative effect on growth of O. oeni, for Lact. hilgardii this effect was only noted for p-coumaric acid. Generally, O. oeni was more sensitive to phenolic acid inactivation than Lact. hilgardii. Significance and Impact of the Study: Eight wine-derived, phenolic acids were compared for their effects on wine lactic acid bacteria. Results indicate that phenolic acids have the capacity to influence growth and survival parameters. The differences found between phenolic compounds could be related to their different chemical structures.
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Citrulline as the main precursor of ethyl carbamate in model fortified wines inoculated with Lactobacillus hilgardii: a marker of the levels in a spoiled fortified wine
Letters in applied microbiology, 2002Co-Authors: Z. Azevedo, José António Couto, Tim HoggAbstract:Aims: The aim of this study was to investigate the production of ethyl carbamate (EC) precursors by Lactobacillus hilgardii in model and Douro fortified wines and to determine the relationship between these compounds and EC levels in this type of wine. Methods and Results: Several model fortified wines and fortified wine inoculated with L. hilgardii were analysed for citrulline and EC formation. A good correlation (R > 0·9) was obtained between citrulline and potential EC (that EC which is formed during heating of sample at 80 °C for 48 h). Conclusions: This correlation allowed us to calculate the potential EC formed during lactic acid bacteria activity in fortified wine. Significance and Impact of the Study: A good correlation was obtained (R=0·92) between measured and calculated EC in spoiled fortified wines, citrulline apparently being the main EC precursor produced by Lact. hilgardii thus contributing to the potential EC in this type of wine.
María C. Manca De Nadra - One of the best experts on this subject based on the ideXlab platform.
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Wine composition plays an important role in the control of carcinogenic precursor formation by Lactobacillus hilgardii X1B
Journal of the science of food and agriculture, 2012Co-Authors: M E Arena, María C. Manca De Nadra, María S Lisi, María Rosa AlbertoAbstract:BACKGROUND: Lactobacillus hilgardii, a wine lactic acid bacterium, is able to use arginine, through the arginine deiminase pathway with the formation of citrulline, a precursor of the carcinogen ethyl carbamate. The influence of different Argentine wine varieties (Merlot, Cabernet Sauvignon and Malbec), on bacterial growth and arginine metabolism was examined. Furthermore, the effect of different components normally present in wines on the enzyme activities of the arginine deiminase system was determined. RESULTS: Malbec wine under all conditions assayed (33, 50 and 100% supplemented wine:basal media) showed higher arginine consumption and citrulline production than the other wines, as well as the highest bacterial growth and survival of Lactobacillus hilgardii X1B. Glucose and L-malic inhibited both arginine deiminase enzymes while fructose and citric acid only inhibited arginine deiminase. The red wines assayed in this study had different composition, and this is an explanation for the different behavior of the bacterium. CONCLUSION: The highest citrulline production in Malbec wine could be correlated with its lower concentrations of glucose, fructose, citric and phenolic acid than the other wines. Therefore, a wine with lower concentration of these sugars and acids could be dangerous due to the formation of ethyl carbamate precursors. Copyright © 2012 Society of Chemical Industry
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Interaction between Oenococcus oeni and Lactobacillus hilgardii isolated from wine. Modification of available nitrogen and biogenic amine production
Biotechnology Letters, 2010Co-Authors: Pedro A. Aredes Fernández, Marta E. Farías, María C. Manca De NadraAbstract:During the mixed culture of Lactobacillus hilgardii 5w, a common spoilage wine bacteria and Oenococcus oeni X_2L, an amensalistic growth response of the malolactic bacteria was produced due to a competition for nitrogenous nutrients, mainly peptides. Arginine was fully consumed and peptide concentration diminished 60% with respect to both pure cultures at the end of exponential growth. Histamine release increased 34% with respect to L. hilgardii single culture. Under the poor nutritional conditions present during winemaking, L. hilgardii could increase histamine production and adversely affect malolactic fermentation conducted by O. oeni and hence the quality of the final product.
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Metabolism of gallic acid and catechin by Lactobacillus hilgardii from wine.
Journal of Agricultural and Food Chemistry, 2004Co-Authors: María Rosa Alberto, Carmen Gómez-cordovés, María C. Manca De NadraAbstract:The ability of Lactobacillus hilgardii 5w to metabolize gallic acid and catechin was evaluated. It was grown in a complex medium containing gallic acid or catechin. The metabolites were analyzed by high-performance liquid chromatography and identified by comparing the retention times and spectral data with the standards of a database. In gallic acid-grown cultures, gallic acid, pyrogallol, catechol, protocatechuic acid, p-hydroxybenzoic acid, p-hydroxybenzaldehyde, and p-hydroxybenzyl alcohol were detected. In catechin-grown cultures, catechin, gallic acid, pyrogallol, catechol, p-hydroxybenzoic acid, acetovanillone, and homovanillic acid were detected. This work presents evidence of gallic acid and catechin degradation by L. hilgardii from wine. Keywords: Lactobacillus hilgardii; gallic acid; catechin
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Metabolism of gallic acid and catechin by Lactobacillus hilgardii from wine.
Journal of agricultural and food chemistry, 2004Co-Authors: María Rosa Alberto, Carmen Gómez-cordovés, María C. Manca De NadraAbstract:The ability of Lactobacillus hilgardii 5w to metabolize gallic acid and catechin was evaluated. It was grown in a complex medium containing gallic acid or catechin. The metabolites were analyzed by high-performance liquid chromatography and identified by comparing the retention times and spectral data with the standards of a database. In gallic acid-grown cultures, gallic acid, pyrogallol, catechol, protocatechuic acid, p-hydroxybenzoic acid, p-hydroxybenzaldehyde, and p-hydroxybenzyl alcohol were detected. In catechin-grown cultures, catechin, gallic acid, pyrogallol, catechol, p-hydroxybenzoic acid, acetovanillone, and homovanillic acid were detected. This work presents evidence of gallic acid and catechin degradation by L. hilgardii from wine.
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The arginine deiminase pathway in the wine lactic acid bacterium Lactobacillus hilgardii X1B: structural and functional study of the arcABC genes.
Gene, 2002Co-Authors: M E Arena, María C. Manca De Nadra, Rosario MuñozAbstract:Abstract The genes implicated in the catabolism of the amino acid arginine by Lactobacillus hilgardii X1B were investigated to assess the potential for formation of ethyl carbamate precursors in wine. L. hilgardii X1B can use arginine via the arginine deiminase pathway. The complete nucleotide sequence of the arc genes involved in this pathway has been determined. They are clustered in an operon-like structure in the order arcABC. No evidence was found for the presence of a homologue of the arcD gene, coding for the arginine/ornithine antiporter. The arc genes have been expressed in Escherichia coli resulting in arginine deiminase (ArcA), ornithine carbamoyltransfera (ArcB) and carbamate kinase (ArcC) activities. The results indicate the need for caution in the selection of lactic acid bacteria for conducting malolactic fermentation in wine since arginine degradation could result in high amounts of ethyl carbamate.
Sanae Okada - One of the best experts on this subject based on the ideXlab platform.
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Lactobacillus kisonensis sp. nov., Lactobacillus otakiensis sp. nov., Lactobacillus rapi sp. nov. and Lactobacillus sunkii sp. nov., heterofermentative species isolated from sunki, a traditional Japanese pickle.
International Journal of Systematic and Evolutionary Microbiology, 2009Co-Authors: Koichi Watanabe, Junji Fujimoto, Yasuaki Tomii, Masae Sasamoto, Hiroshi Makino, Yuko Kudo, Sanae OkadaAbstract:Thirty six Gram-positive, rod-shaped, non-spore-forming, non-motile bacterial strains were isolated from the non-salted pickle solution used in producing sunki products, a traditional Japanese pickle. The novel strains were discriminated and separated into four groups by amplified fragment length polymorphism profiling, and by analysis based on recA gene sequences. The strains were classified into four species groups belonging to the Lactobacillus buchneri species group, which consists of L. buchneri, Lactobacillus diolivorans, Lactobacillus hilgardii, Lactobacillus kefiri, Lactobacillus parabuchneri and Lactobacillus parakefiri. The phenotypic and genotypic features of the four groups demonstrated that they represented four novel species, for which the names Lactobacillus kisonensis sp. nov. (type strain YIT 11168T=NRIC 0741T=JCM 15041T=DSM 19906T), Lactobacillus otakiensis sp. nov. (type strain YIT 11163T=NRIC 0742T=JCM 15040T=DSM 19908T), Lactobacillus rapi sp. nov. (type strain YIT 11204T=NRIC 0743T=JCM 15042T=DSM 19907T) and Lactobacillus sunkii sp. nov. (type strain YIT 11161T=NRIC 0744T=JCM 15039T=DSM 19904T) are proposed.
