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Potassium Lactate as a Strategy for Sodium Content Reduction without Compromising Salt-Associated Antimicrobial Activity in Salami. Foods 2021; 10:foods10010114. [PMID: 33430446 PMCID: PMC7826916 DOI: 10.3390/foods10010114] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/27/2020] [Accepted: 01/04/2021] [Indexed: 12/18/2022] Open
Abstract
Reformulating recipes of ready-to-eat meat products such as salami to reduce salt content can mitigate the negative health impacts of a high salt diet. We evaluated the potential of potassium lactate (KL) as a sodium chloride (NaCl) replacer during salami production. NaCl and KL stress tolerance comparisons showed that four food-derived Listeria innocua isolates were suitable as biologically safe Listeria monocytogenes surrogates. Effects of the high salt (4% NaCl) concentration applied in standard salami recipes and a low salt (2.8% NaCl) plus KL (1.6%) combination on product characteristics and growth of contaminating Listeria and starter culture were compared. Simulated salami-ripening conditions applied in meat simulation broth and beef showed that the low salt plus KL combination retained similar to superior anti-Listeria activity compared to the high salt concentration treatment. Salami challenge tests showed that the low NaCl plus KL combination had comparable anti-Listeria activity as the high NaCl concentration during ripening and storage. No significant differences were detected in starter culture growth profiles and product characteristics between the high NaCl and low NaCl plus KL combination treated salami. In conclusion, KL replacement enabled a 30% NaCl reduction without compromising the product quality and antimicrobial benefits of high NaCl concentration inclusion.
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Bukhari SA, Salman M, Numan M, Javed MR, Zubair M, Mustafa G. Characterization of antifungal metabolites produced by Lactobacillus plantarum and Lactobacillus coryniformis isolated from rice rinsed water. Mol Biol Rep 2020; 47:1871-1881. [PMID: 32006197 DOI: 10.1007/s11033-020-05281-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2019] [Accepted: 01/24/2020] [Indexed: 11/29/2022]
Abstract
A recent spike in demand for chemical preservative free food has derived the scientific community to develop natural ways of food preservation. Therefore, bio-preservation could be considered as the great alternative over chemical ones owing to its potential to increase shelf-life and nutritional values of foodstuffs. In the present study, lactic acid producing bacterial species were isolated from rice rinsed water and identified by 16S rRNA gene sequencing as Lactobacillus plantarum BCH-1 (KX388380) and Lactobacillus coryniformis BCH-4 (KX388387). Antifungal metabolites from both Lactobacillus species were extracted by polarity-based solvents in which ethyl acetate showed remarkable antifungal activity against Aspergillus flavus and Aspergillus fumigatus by disc diffusion assay. Different organic acids and fatty acids have been identified by reversed-phase high-performance liquid chromatography (RP-HPLC) and gas chromatography-mass spectrometry (GC-MS) analysis, respectively. Lactic acid and citric acid were the major organic acids found in ethyl acetate fractions of L. plantarum and L. coryniformis, respectively. Similarly, 9,12-otadecadienoic acid (Z,Z)-methyl ester and hexadecanoic acid, methyl ester were the major fatty acids found in n-hexane fractions of L. plantarum and L. coryniformis respectively. Moreover, the isolation of novel antifungal metabolites from locally isolated Lactobacillus species was focused and it was revealed that organic acids are important contributors towards antifungal potential. A novel fatty acid (i.e. 12-hydroxydodecanoic acid) has also been explored and found as potential metabolite against filamentous fungi. Conclusively, various metabolites isolated from non-dairy source showed antifungal activity especially against Aspergillus species. Hence, these metabolites have been considered as a good choice for bio-preservation.
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Affiliation(s)
| | - Mahwish Salman
- Department of Biochemistry, Government College University, Faisalabad, Pakistan
| | - Muhammad Numan
- Department of Biochemistry, Government College University, Faisalabad, Pakistan
| | - Muhammad Rizwan Javed
- Department of Bioinformatics and Biotechnology, Government College University, Faisalabad, Pakistan
| | - Muhammad Zubair
- Department of Chemistry, Faculty of Sciences, University of Gujrat, Gujrat, Pakistan
| | - Ghulam Mustafa
- Department of Biochemistry, Government College University, Faisalabad, Pakistan.
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Design of biosystems to provide healthy and safe food—part B: effect on microbial flora and sensory quality of orange juice. Eur Food Res Technol 2019. [DOI: 10.1007/s00217-018-03228-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Caro Velez CA, León Peláez ÁM. Capacidad antifúngica de sobrenadantes libres de células obtenidos de la fermentación de un sustrato de “panela” con gránulos de kefir de agua. REVISTA COLOMBIANA DE BIOTECNOLOGÍA 2015. [DOI: 10.15446/rev.colomb.biote.v17n2.42758] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
<p>El kefir de agua (KA) es una bebida fermentada medianamente ácida elaborada con soluciones azucaradas y fermentada por un consorcio de microorganismos, principalmente bacterias ácido lácticas (BAL) y levaduras (LEV), embebidas en un polisacárido llamado gránulo de KA. La presencia de hongos y sus toxinas es un problema de la producción de alimentos, como Aspergillus ochraceus y sus micotoxinas especialmente en café y vino. Entre algunas alternativas que se han evaluado para su inhibición se incluyen las bacterias ácido lácticas y productos fermentados en general.</p><p>El objetivo principal de esta investigación fue evaluar la capacidad del KA en inhibir o retrasar el crecimiento de <em>A. ochraceus</em>. Se emplearon 8 sobrenadantes libres de células (SLC) obtenidos de diferentes fermentaciones de panela con gránulos de KA y con diferentes concentraciones de ácidos orgánicos (láctico y acético). Se hicieron fermentaciones con gránulos de KA en solución de panela por periodos de 32,5 h, a 25, 30 y 37 °C. Se determinaron la cinética de acidificación; el incremento de biomasa y se hizo el recuento de los grupos de microorganismos que componen el gránulo. A 25 °C se determinó el mayor aumento de biomasa (92%). La temperatura de fermentación afectó el recuento de los microorganismos que conforman el gránulo, principalmente las BAL, disminuyendo su cantidad a la máxima temperatura de fermentación (37 °C) (6,4x107UFC ml-1), comparado con la mínima temperatura (25 ºC) (4,0x106 UFC ml-1). El fermento que presentó mayor actividad antifúngica fue el SLC5 (pH: 3,2; temperatura de fermentación: 30 °C). El poder inhibitorio se atribuyó a los ácidos orgánicos producidos durante la fermentación, aunque no se puede descartar que hayan actuado otras sustancias no cuantificadas.</p><p>Se pudo comprobar que el KA puede fermentar y aumentar su biomasa en un sustrato como el agua de panela y que sus SLC tienen la capacidad de reducir el crecimiento de <em>A. ochraceus</em>.</p>
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Dagnas S, Gougouli M, Onno B, Koutsoumanis KP, Membré JM. Modeling red cabbage seed extract effect on Penicillium corylophilum: Relationship between germination time, individual and population lag time. Int J Food Microbiol 2015; 211:86-94. [PMID: 26188372 DOI: 10.1016/j.ijfoodmicro.2015.07.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 06/14/2015] [Accepted: 07/05/2015] [Indexed: 11/16/2022]
Abstract
The inhibitory effect of a red cabbage seed extract on germination time, individual (single spore) and population lag time of Penicillium corylophilum was studied. First, to compare the biological variability of single spore germination and lag times under stressful conditions, data were collected at levels of red cabbage seed extract varying from 0 to 10 mg/g (150 spores observed in each trial of germination, ca 50 spores in each individual lag experiment). Experiments were performed on malt agar at 25 °C, pH 5.2, aw 0.99. The data, without any transformation, were statistically analyzed; several probability distribution functions were used to fit the cumulated germination times and the individual lag times of spores. In both cases, the best fit was obtained with the Normal distribution. In parallel, lag times at the population level (ca 2000 spores per trial) were collected for the same range of plant extract. Not surprisingly, the difference between individual and population lag times could be explained by a stochastic process. More interestingly, it was shown that under stressful conditions, the population lag time did not correspond to the time required for germination of 95% of spores, but to a much longer time. Finally, it was deduced from the statistical analysis, completed by microscopic observations, that the plant extract affected mainly the hyphal elongation (and then the lag time) and not the germination. Next, secondary models were developed to quantify the effect of red cabbage seed extract on the median of germination times, individual and population lag times. The Minimum Inhibitory Concentrations (MICs) were estimated. It was shown that the red cabbage seed extract MIC for P. corylophilum lag time did not depend on the inoculum load. Application of the secondary models allowed us to conclude that under the conditions of our experiment, the addition of 10 mg/g of red cabbage seed extract enabled extension of lag time to two weeks.
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Affiliation(s)
- Stéphane Dagnas
- L'Université Nantes Angers Le Mans, Oniris, Nantes F-44322, cedex 3, France
| | - Maria Gougouli
- Laboratory of Food Microbiology and Hygiene, Department of Food Science and Technology, School of Agriculture, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - Bernard Onno
- L'Université Nantes Angers Le Mans, Oniris, Nantes F-44322, cedex 3, France
| | - Konstantinos P Koutsoumanis
- Laboratory of Food Microbiology and Hygiene, Department of Food Science and Technology, School of Agriculture, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - Jeanne-Marie Membré
- Institut National de la Recherche Agronomique, UMR1014 Sécurité des Aliments Microbiologie, Nantes F-44307, France; L'Université Nantes Angers Le Mans, Oniris, Nantes F-44322, cedex 3, France.
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Dagnas S, Gauvry E, Onno B, Membré JM. Quantifying Effect of Lactic, Acetic, and Propionic Acids on Growth of Molds Isolated from Spoiled Bakery Products. J Food Prot 2015; 78:1689-98. [PMID: 26319723 DOI: 10.4315/0362-028x.jfp-15-046] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The combined effect of undissociated lactic acid (0 to 180 mmol/liter), acetic acid (0 to 60 mmol/liter), and propionic acid (0 to 12 mmol/liter) on growth of the molds Aspergillus niger, Penicillium corylophilum, and Eurotium repens was quantified at pH 3.8 and 25°C on malt extract agar acid medium. The impact of these acids on lag time for growth (λ) was quantified through a gamma model based on the MIC. The impact of these acids on radial growth rate (μ) was analyzed statistically through polynomial regression. Concerning λ, propionic acid exhibited a stronger inhibitory effect (MIC of 8 to 20 mmol/liter depending on the mold species) than did acetic acid (MIC of 23 to 72 mmol/liter). The lactic acid effect was null on E. repens and inhibitory on A. niger and P. corylophilum. These results were validated using independent sets of data for the three acids at pH 3.8 but for only acetic and propionic acids at pH 4.5. Concerning μ, the effect of acetic and propionic acids was slightly inhibitory for A. niger and P. corylophilum but was not significant for E. repens. In contrast, lactic acid promoted radial growth of all three molds. The gamma terms developed here for these acids will be incorporated in a predictive model for temperature, water activity, and acid. More generally, results for μ and λ will be used to identify and evaluate solutions for controlling bakery product spoilage.
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Affiliation(s)
- Stéphane Dagnas
- L'Université Nantes Angers Le Mans, Oniris, Nantes F-44322 cedex 3, France
| | - Emilie Gauvry
- L'Université Nantes Angers Le Mans, Oniris, Nantes F-44322 cedex 3, France
| | - Bernard Onno
- L'Université Nantes Angers Le Mans, Oniris, Nantes F-44322 cedex 3, France
| | - Jeanne-Marie Membré
- L'Université Nantes Angers Le Mans, Oniris, Nantes F-44322 cedex 3, France; Institut National de la Recherche Agronomique, UMR1014 Sécurité des Aliments et Microbiologie, Nantes F-44307, France.
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Sedghi H, Sani AM, Najafi MN, Shariati MA. Effect of sodium lactate /sodium diacetate in combination with sodium nitrite on physiochemical, microbial properties and sensory evaluation of cow sausage. POTRAVINARSTVO 2014. [DOI: 10.5219/378] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Sodium nitrite has been always considered as one of the common additives due to its antibacterial effects on Clostridium botulinum and meat products' color, however it produces cancer creating nitrosamine. Recently, organic acids and their salts such as lactates have been employed as antimicrobial compounds. Lactates also improve organileptic properties including color, texture and taste and antioxidant properties. Sodium lactate causes to more reduction of anaerobic spore former bacteria than nitrite, inhibits botulin produced by Clostridium botulinum. Sodium lactate produces a permanent reddish pink color through reduction of deoxymygloboline and producing deoxymyoglobuline. In this study, the decrease of sodium nitrite amount from 120ppm to 15ppm by adding sodium lactate / sodium diacetate led to achieve an acceptable product. The best results revealed through adding 3.0625% of sodium lactate / sodium diacetate in combination with 30ppm sodium nitrite. Results also exhibited more reduction of pathogens' growth than nitrite, enhanced flavor slightly, but unable to produce reddish pink color as produced by nitrite. Results also exhibited that sodium lactate / diacetate cause to retard in microbial growth, reducing chemical change, enhance sensory properties, partially improvement in taste and texture. Although inappropriate color demonstrated sodium lactate / diacetate's inability in red pink color production in 4th sample (contains 15 ppm nitrite), its synergy effect in combination with sodium nitrite on nitroso myoglobuline production has been proven, led to sodium nitrite reduction in sausages.
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Svanström Å, Boveri S, Boström E, Melin P. The lactic acid bacteria metabolite phenyllactic acid inhibits both radial growth and sporulation of filamentous fungi. BMC Res Notes 2013; 6:464. [PMID: 24229396 PMCID: PMC3835548 DOI: 10.1186/1756-0500-6-464] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Accepted: 11/08/2013] [Indexed: 11/29/2022] Open
Abstract
Background Food spoilage caused by molds is a severe problem. In food and feed, e.g. dairy products, sourdough bread and silage, lactic acid bacteria are used as starter cultures. Besides lactic and acetic acid, some strains produce other low molecular weight compounds with antifungal activities. One of these metabolites is phenyllactic acid (PLA), well known for its antifungal effect. The inhibitory effect of PLA has only partially been investigated, and the objective of this study was to elucidate in detail the antifungal properties of PLA. Results We investigated the outgrowth of individual conidia from Aspergillus niger, Cladosporium cladosporioides and Penicillium roqueforti, and observed the morphologies of resulting colonies on solid media using different acid concentrations. We found that PLA inhibits molds similar to weak acid preservatives. Furthermore, it has an additional activity: at sub-inhibitory concentrations, fungal colonies displayed slower radial growth and inhibited sporulation. The L isoform of PLA is a more potent inhibitor than the D form. Increased expression of phiA was observed during PLA treatment. This gene was initially identified as being induced by Streptomyces-produced macrolide antibiotics, and is shown to be a structural protein in developed cells. This suggests that PhiA may act as a general stress protectant in fungi. Conclusion From a food protection perspective, the results of this study support the usage of lactic acid bacteria strains synthesizing PLA as starter cultures in food and feed. Such starter cultures could inhibit spore synthesis, which would be beneficial as many food borne fungi are spread by airborne spores.
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Affiliation(s)
| | | | | | - Petter Melin
- Uppsala BioCenter, Department of Microbiology, Swedish University of Agricultural Sciences, P,O, Box 7025, Uppsala SE-750 07, Sweden.
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Chibeu A, Agius L, Gao A, Sabour PM, Kropinski AM, Balamurugan S. Efficacy of bacteriophage LISTEX™P100 combined with chemical antimicrobials in reducing Listeria monocytogenes in cooked turkey and roast beef. Int J Food Microbiol 2013; 167:208-14. [DOI: 10.1016/j.ijfoodmicro.2013.08.018] [Citation(s) in RCA: 103] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 08/22/2013] [Accepted: 08/23/2013] [Indexed: 11/24/2022]
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Abstract
This study aims to investigate the ability of lactic acid bacteria (LAB) to remove patulin (PAT) from aqueous solution with respect to the bacterial viability, initial PAT concentration, incubation time, temperature, and pH. The removal of PAT determined by high-performance liquid chromatography (HPLC) coupled with UV detector. The maximum PAT uptake was achieved by Bifidobacterium bifidum 6071 and Lactobacillus rhamnosus 6149 strains (52.9% and 51.1%) for viable and (54.1% and 52.0%) for nonviable cells after 24 h incubation. The highest removal of PAT was at pH 4.0 and 37 °C and increased with decreasing of toxin levels. The removal ability of selected strains could represent new strategies for a possible application in contaminated food products and animal feed.
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Affiliation(s)
- Shaimaa Hatab
- Northwest A&F University, College of Food Science and Engineering, Yangling 712100, China.
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León Peláez A, Serna Cataño C, Quintero Yepes E, Gamba Villarroel R, De Antoni G, Giannuzzi L. Inhibitory activity of lactic and acetic acid on Aspergillus flavus growth for food preservation. Food Control 2012. [DOI: 10.1016/j.foodcont.2011.09.024] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Bradley E, Williams J, Schilling M, Coggins P, Crist C, Yoder S, Campano S. Effects of sodium lactate and acetic acid derivatives on the quality and sensory characteristics of hot-boned pork sausage patties. Meat Sci 2011; 88:145-50. [DOI: 10.1016/j.meatsci.2010.12.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2010] [Revised: 11/22/2010] [Accepted: 12/02/2010] [Indexed: 10/18/2022]
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Shabala L, McMeekin T, Shabala S. Osmotic adjustment and requirement for sodium in marine protist thraustochytrid. Environ Microbiol 2011; 11:1835-43. [PMID: 20849566 DOI: 10.1111/j.1462-2920.2009.01908.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A non-invasive ion-selective microelectrode technique was used to elucidate the ionic mechanisms of osmotic adjustment in a marine protist thraustochytrid. Hypoosmotic stress caused significant efflux of Na(+), Cl(-) and K(+) from thraustochytrid cells. Model calculations showed that almost complete osmotic adjustment was achieved within the first 30 min after stress onset. Of these, sodium was the major contributor (more than half of the total osmotic adjustment), with chloride being the second major contributor. The role of K(+) in the process of osmotic adjustment was relatively small. Changes in Ca(2+) and H(+) flux were attributed to intracellular signalling. Ion flux data were confirmed by growth experiments. Thraustochytrium cells showed normal growth patterns even when grown in a sodium-free solution provided the medium osmolality was adjusted by mannitol to one of the seawater. That suggests that the requirement of sodium for thraustochytrid growth cycle is due to its role in cell osmotic adjustment rather than because of the direct Na(+) involvement in cell metabolism. Altogether, these data demonstrate the evidence for turgor regulation in thraustochytrids and suggest that these cells may be grown in the absence of sodium providing that cell turgor is adjusted by some other means.
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Affiliation(s)
- Lana Shabala
- School of Agricultural Science, University of Tasmania, Private Bag 54, Hobart, Tas. 7001, Australia
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14
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Combined Use of Modified Atmosphere Packaging and Natural Compounds for Food Preservation. FOOD ENGINEERING REVIEWS 2010. [DOI: 10.1007/s12393-010-9013-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Melin P, Stratford M, Plumridge A, Archer DB. Auxotrophy for uridine increases the sensitivity of Aspergillus niger to weak-acid preservatives. Microbiology (Reading) 2008; 154:1251-1257. [DOI: 10.1099/mic.0.2007/014332-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Petter Melin
- Department of Microbiology, Swedish University of Agricultural Sciences, PO Box 7025, SE-750 07 Uppsala, Sweden
- School of Biology, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Malcolm Stratford
- School of Biology, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Andrew Plumridge
- School of Biology, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - David B. Archer
- School of Biology, University of Nottingham, University Park, Nottingham NG7 2RD, UK
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SMULDERS FJM, BARENDSEN P, VAN LOGTESTIJN JG, MOSSEL DAA, VAN DER MAREL GM. Review: Lactic acid: considerations in favour of its acceptance as a meat decontamininant. Int J Food Sci Technol 2007. [DOI: 10.1111/j.1365-2621.1986.tb00420.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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PAPADOPOULOS LS, MILLER RK, ACUFF GR, VANDERZANT C, CROSS HR. Effect of Sodium Lactate on Microbial and Chemical Composition of Cooked Beef during Storage. J Food Sci 2006. [DOI: 10.1111/j.1365-2621.1991.tb05276.x] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Affiliation(s)
- S.‐I. Hong
- Author Hong is affiliated with the Korea Food Research Institute, San 46–1, Baekhyun‐dong, Bundang‐gu, Seongnam‐si, Kyonggi‐do 463–420, Korea
| | - Y.‐R. Pyun
- Author Pyun is with the Dept. of Biotechnology & Bioproducts Research Center, Yonsei Univ., Seoul 120–749, Korea
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Nuñez de Gonzalez M, Keeton J, Ringer L. Sensory and Physicochemical Characteristics of Frankfurters Containing Lactate with Antimicrobial Surface Treatments. J Food Sci 2006. [DOI: 10.1111/j.1365-2621.2004.tb11009.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Pierre PM, Ryser ET. Inactivation of Escherichia coli O157:H7, Salmonella typhimurium DT104, and Listeria monocytogenes on inoculated alfalfa seeds with a fatty acid-based sanitizer. J Food Prot 2006; 69:582-90. [PMID: 16541689 DOI: 10.4315/0362-028x-69.3.582] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Alfalfa seeds were inoculated with a three-strain cocktail of Escherichia coli O157:H7, Salmonella enterica subsp. enterica serovar Typhimurium DT104, or Listeria monocytogenes by immersion to contain approximately 6 to 8 log CFU/g and then treated with a fatty acid-based sanitizer containing 250 ppm of peroxyacid, 1,000 ppm of caprylic and capric acids (Emery 658), 1,000 ppm of lactic acid, and 500 ppm of glycerol monolaurate at a reference concentration of 1X. Inoculated seeds were immersed at sanitizer concentrations of 5X, 10X, and 15X for 1, 3, 5, and 10 min and then assessed for pathogen survivors by direct plating. The lowest concentration that decreased all three pathogens by >5 log was 15. After a 3-min exposure to the 15X concentration, populations of E. coli O157:H7, Salmonella Typhimurium DT104, and L. monocytogenes decreased by >5.45, >5.62, and >6.92 log, respectively, with no sublethal injury and no significant loss in seed germination rate or final sprout yield. The components of this 15x concentration (treatment A) were assessed independently and in various combinations to optimize antimicrobial activity. With inoculated seeds, treatment C (15,000 ppm of Emery 658, 15,000 ppm of lactic acid, and 7,500 ppm of glycerol monolaurate) decreased Salmonella Typhimurium, E. coli O157:H7, and L. monocytogenes by 6.23 and 5.57 log, 4.77 and 6.29 log, and 3.86 and 4.21 log after 3 and 5 min of exposure, respectively. Treatment D (15,000 ppm of Emery 658 and 15,000 ppm of lactic acid) reduced Salmonella Typhimurium by >6.90 log regardless of exposure time and E. coli )157:H7 and L. monocytogenes by 4.60 and >5.18 log and 3.55 and 3.14 log after 3 and 5 min, respectively. No significant differences (P > 0.05) were found between treatments A, C, and D. Overall, treatment D, which contained Emery 658 and lactic acid as active ingredients, reduced E. coli O157:H7, Salmonella Typhimurium, and L. monocytogenes populations by 3.55 to >6.90 log and may provide a viable alternative to the recommended 20,000 ppm of chlorine for sanitizing alfalfa seeds.
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Affiliation(s)
- Pascale M Pierre
- Department of Food Science and Human Nutrition, 2108 South Anthony Hall, Michigan State University, East Lansing, Michigan 48824, USA
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Nielsen J. Modelling the growth of filamentous fungi. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2005; 46:187-223. [PMID: 1636480 DOI: 10.1007/bfb0000711] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Despite the considerable industrial importance of filamentous fungi there have been very few attempts to model the complex growth process of these microorganisms. With a new generation of high performance, computerized bioreactors and new analytical techniques it is possible to obtain the necessary experimental data for setting up reliable structured models describing the growth process of filamentous fungi. It is therefore interesting to review the mathematical models described previously in the literature and the experimental data on which these models are built. Only structured models are considered due to the complex metabolism of filamentous fungi and to the natural cellular structuring of the biomass, i.e. the biomass can be divided into different cell types. In order to set up good structured models it is strictly necessary to have a detailed knowledge of the mechanisms underlying the growth process. This involves both biochemical insight and understanding of the interactions between different macromolecules and cytological organelles.
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Affiliation(s)
- J Nielsen
- Department of Biotechnology, Technical University of Denmark, Lyngby
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Octave S, Amborabé BE, Luini E, Ferreira T, Fleurat-Lessard P, Roblin G. Antifungal effects of cysteine towards Eutypa lata, a pathogen of vineyards. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2005; 43:1006-13. [PMID: 16325412 DOI: 10.1016/j.plaphy.2005.10.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2005] [Indexed: 05/05/2023]
Abstract
Cysteine inhibited mycelial growth of the pathogenic fungus affecting grapevines Eutypa lata Pers. Fr. Tul. and C. Tul. in a concentration-dependent manner. The threshold value (defined by the concentration inducing a growth inhibition higher than 5%) was 0.5 mM. A 10 mM concentration induced a complete inhibition of growth and triggered necrotic processes as evidenced by an increasing number of nuclei stained by propidium iodide. In conditions mimicking the plant environment (in particular, a pH near the apoplastic value, i.e. 5.5), 6 mM cysteine induced dramatic modifications in the structural organization of the mycelium (wall, mitochondria, vacuoles and nucleus) leading to death of the hyphae. The antifungal effect of the molecule increased at the acidic experimental pH (pH 4.1). The effect was highly specific to cysteine since modifying the molecular arrangement or masking the SH-function hindered the antifungal efficiency. Cysteine spectrum of action was broad among the various strains of E. lata tested. However, a lower efficiency was observed against fungal species intervening in other grapevine diseases (esca, black dead arm). Besides its direct antifungal effect, the role of cysteine presents particular interest in the fight against fungal pathogens since it triggered an excretion of ergosterol, a compound with elicitor properties. Therefore, cysteine may indirectly increase plant defense reactions.
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Affiliation(s)
- Stéphane Octave
- Laboratoire de Physiologie, Biochimie, Biologie Moléculaire Végétales et Génétique des levures, Université de Poitiers (CNRS, UMR 6161), 40, avenue du Recteur Pineau, 86022 Poitiers cedex, France
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23
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Rodríguez-Sáiz M, Díez B, Barredo JL. Why did the Fleming strain fail in penicillin industry? Fungal Genet Biol 2005; 42:464-70. [PMID: 15809010 DOI: 10.1016/j.fgb.2005.01.014] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2004] [Revised: 01/24/2005] [Accepted: 01/25/2005] [Indexed: 11/24/2022]
Abstract
Penicillin, discovered 75 years ago by Sir Alexander Fleming in Penicillium notatum, laid the foundations of modern antibiotic chemotherapy. Early work was carried out on the original Fleming strain, but it was later replaced by overproducing strains of Penicillium chrysogenum, which became the industrial penicillin producers. We show how a C(1357)-->T (A394V) change in the gene encoding PahA in P. chrysogenum may help to explain the drawback of P. notatum. PahA is a cytochrome P450 enzyme involved in the catabolism of phenylacetic acid (PA; a precursor of penicillin G). We expressed the pahA gene from P. notatum in P. chrysogenum obtaining transformants able to metabolize PA (P. chrysogenum does not), and observing penicillin production levels about fivefold lower than that of the parental strain. Our data thus show that a loss of function in P. chrysogenum PahA is directly related to penicillin overproduction, and support the historic choice of P. chrysogenum as the industrial producer of penicillin.
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Affiliation(s)
- Marta Rodríguez-Sáiz
- R&D Biology, Antibióticos S. A., Avenida de Antibióticos 59-61, E-24009 León, Spain
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24
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Amborabé BE, Octave S, Roblin G. Influence of temperature and nutritional requirements for mycelial growth of Eutypa lata, a vineyard pathogenic fungus. C R Biol 2005; 328:263-70. [PMID: 15810550 DOI: 10.1016/j.crvi.2005.01.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Eutypa dieback (dying arm disease, eutypiosis) is a very devastating disease in many grape-producing areas around the world. This vascular disease is induced by the ascomycete Eutypa lata Pers. Fr. Tul & C. Tul. invading the trunk by pruning wounds. The environmental factors and the nutritional requirements regulating fungus development are yet poorly known. This work shows that the isolated strain of E. lata was able to grow in a large temperature range (2-30 degrees C). However, a higher temperature (35 degrees C) presented inhibitory effects on mycelial growth. E. lata was able to use various osidic molecules (C5, C6, C12, C18, C24, and starch); showing thus a large adaptation to the carbon source supplied. As nitrogen source, it used salts and numerous natural amino acids. A significant result was obtained with cysteine presenting obvious antifungal properties. This effect can further be used with the aim of setting up a curative treatment of the disease.
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Affiliation(s)
- Bénigne-Ernest Amborabé
- Laboratoire de biochimie, physiologie et biologie moléculaire végétales, UMR CNRS 6161, université de Poitiers, bât. Botanique, 40, av. du Recteur-Pineau, 86022 Poitiers, France
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25
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26
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Pokorný R, Hudecová D, Burgstaller W, Varecka L. Changes in properties of glutamate transport in Trichoderma viride vegetative mycelia upon adaptation to glutamate as carbon source. FEMS Microbiol Lett 2004; 230:123-8. [PMID: 14734174 DOI: 10.1016/s0378-1097(03)00884-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The U-(14)C-labelled glutamate uptake was measured in both sucrose- and glutamate-grown mycelia of Trichoderma viride. The biomass yield was five-fold lower with glutamate as a sole carbon source. The rate of glutamate transport measured at a glutamate concentration of 1 mM remained unchanged in glutamate-grown mycelia whereas the properties of the glutamate transport were substantially changed compared to sucrose-grown mycelia. The glutamate uptake in both sucrose- and glutamate-grown mycelia was inhibited by an uncoupler (3,3',4',5-tetrachlorosalicylanilide) but the inhibitory efficiency was higher in the latter. The affinity of the permease to glutamate increased approximately five-fold in the glutamate-grown mycelia (about 76 microM compared to about 16 microM). The pH optimum for glutamate uptake was 4 in sucrose-grown mycelia but the glutamate-grown mycelia had two pH optima, one at pH 4 and the second between pH 6 and 7. The inhibition of glutamate uptake by other amino acids yielded different inhibitory patterns in the two mycelia under study. The glutamate uptake in mycelia of different ages also showed differences in both transport rate and temporal pattern. The results show that the growth of mycelia on glutamate led to the appearance of an additional permease with different properties and suggest that only this permease is operating in mycelia grown on glutamate.
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Affiliation(s)
- Richard Pokorný
- Department of Biochemistry and Microbiology, Slovak University of Technology, Bratislava, Slovak Republic
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27
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Mahrour A, Caillet S, Nketsa-Tabiri J, Lacroix M. Microbial and sensory quality of marinated and irradiated chicken. J Food Prot 2003; 66:2156-9. [PMID: 14627299 DOI: 10.4315/0362-028x-66.11.2156] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Chicken legs were subjected to two pretreatments (packaged in air or marinated in natural plant extracts and then packaged in air) followed by irradiation (0, 3, or 5 kGy). The control and irradiated chicken legs were stored at 4 degrees C and underwent microbial analysis (mesophilic aerobic plate counts and Salmonella detection) and sensory evaluation at predetermined intervals. Microbial analysis indicated that irradiation had a significant effect (P < or = 0.05) on the mesophilic aerobic plate counts of the poultry. For each treatment, the bacterial growth decreased with an increase of irradiation dose. The marinade had an additive effect with irradiation in reducing bacterial growth and controlling proliferation during storage at 4 +/- 1 degree C. No Salmonella was observed until day 12 in marinated chicken irradiated at 3 kGy and for all experiments with chicken legs stored under air or marinated at 5 kGy. However, Salmonella was found in chicken legs irradiated at 3 kGy in air and in nonirradiated samples. The sensory evaluation indicated a significant (P < or = 0.05) difference in odor and flavor intensities between the irradiated chicken at 5 kGy and the control. No significant difference was found (P > 0.05) between the marinated chicken irradiated at 5 kGy and the control.
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Affiliation(s)
- A Mahrour
- Canadian Irradiation Center, INRS-Institut Armand-Frappier, Université du Québec, 531 Blvd. des Prairies, Laval, Quebec, Canada H7V 1B7
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28
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Establishment and application of an in vitro methodology to study the effects of organic acids on coliform and lactic acid bacteria in the proximal part of the gastrointestinal tract of piglets. Anim Feed Sci Technol 2002. [DOI: 10.1016/s0377-8401(02)00069-x] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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29
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Rodríguez-Sáiz M, Barredo JL, Moreno MA, Fernández-Cañón JM, Peñalva MA, Díez B. Reduced function of a phenylacetate-oxidizing cytochrome p450 caused strong genetic improvement in early phylogeny of penicillin-producing strains. J Bacteriol 2001; 183:5465-71. [PMID: 11544206 PMCID: PMC95435 DOI: 10.1128/jb.183.19.5465-5471.2001] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The single-copy pahA gene from Penicillium chrysogenum encodes a phenylacetate 2-hydroxylase that catalyzes the first step of phenylacetate catabolism, an oxidative route that decreases the precursor availability for penicillin G biosynthesis. PahA protein is homologous to cytochrome P450 monooxygenases involved in the detoxification of xenobiotic compounds, with 84% identity to the Aspergillus nidulans homologue PhacA. Expression level of pahA displays an inverse correlation with the penicillin productivity of the strain and is subject to induction by phenylacetic acid. Gene expression studies have revealed a reduced oxidative activity of the protein encoded by pahA genes from penicillin-overproducing strains of P. chrysogenum compared to the activity conferred by phacA of A. nidulans. Sequencing and expression of wild-type pahA from P. chrysogenum NRRL 1951 revealed that an L181F mutation was responsible for the reduced function in present industrial strains. The mutation has been tracked down to Wisconsin 49-133, a mutant obtained at the Department of Botany of the University of Wisconsin in 1949, at the beginning of the development of the Wisconsin family of strains.
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Affiliation(s)
- M Rodríguez-Sáiz
- Laboratorio de Biotecnología, Antibióticos S. A., 24009 León, Spain
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30
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Boskou G, Debevere J. Shelf-life extension of cod fillets with an acetate buffer spray prior to packaging under modified atmospheres. FOOD ADDITIVES AND CONTAMINANTS 2000; 17:17-25. [PMID: 10793851 DOI: 10.1080/026520300283559] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Fresh cod fillets (Gadus morhua) were sprayed with a 10% acetate buffer (pH 5.6), packed with an industrial gas-flushing packaging machine under modified atmospheres (50% CO2--45% O2--5% N2, 2 cm3/1 g gas/product ratio) and stored at 7 degrees C for 12 days. Control cod fillets were directly packed and stored under the same conditions. A reduction of the aerobic plate counts was observed immediately after the cod fillets had been sprayed. During storage under modified atmospheres, there was complete inhibition of H2S-producing bacteria and Enterobacteriaceae in the treated cod fillets. Production of total volatile bases and trimethylamine (TMA) was inhibited in treated fillets for 10 days' storage under modified atmospheres. Inhibition of TMA production can be attributed to growth inhibition of H2S-producing bacteria, inhibition of the trimethylamine oxide (TMAO)-dependent metabolism of TMAO-reducing bacteria and the stable pH during storage. The shelf-life, at 7 degrees C, of treated cod fillets, based on cooked flavour score, was almost 12 days, ca 8 days more than shelf-life of the control fillets.
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Affiliation(s)
- G Boskou
- Department of Food Technology and Nutrition, Faculty of Agricultural and Applied Biological Sciences, University of Ghent, Belgium.
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31
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Abstract
Uptake of phenylacetic acid, the side-chain precursor of benzylpenicillin, was studied in Penicillium chrysogenum Wisconsin 54-1255 and in a strain yielding high levels of penicillin. In penicillin fermentations with the high-yielding strain, 100% recovery of phenylacetic acid in benzylpenicillin was found, whereas in the Wisconsin strain only 17% of the supplied phenylacetic acid was incorporated into benzylpenicillin while the rest was metabolized. Accumulation of total phenylacetic acid-derived carbon in the cells was nonsaturable in both strains at high external concentrations of phenylacetic acid (250-3500 microM), and in the high-yielding strain at low phenylacetic acid concentrations (2. 8-100 microM), indicating that phenylacetic acid enters the cells by simple diffusion, as concluded earlier for P. chrysogenum by other authors. However, at low external concentrations of phenylacetic acid saturable accumulation appeared in the Wisconsin strain. HPLC-analyses of cell extracts from the Wisconsin strain showed that phenylacetic acid was metabolized immediately after entry into the cells and different [14C]-labeled metabolites were detected in the cells. Up to approximately 50% of the accumulated phenylacetic acid was metabolized during the transport-assay period, the conversion having an impact on the uptake experiments. Nevertheless, accumulation of free unchanged phenylacetic acid in the cells showed saturation kinetics, suggesting the possible involvement of a high-affinity carrier in uptake of phenylacetic acid in P. chrysogenum Wisconsin 54-1255. At high concentrations of phenylacetic acid, contribution to uptake by this carrier is minor in comparison to simple diffusion and therefore, of no importance in the industrial production of penicillin.
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Affiliation(s)
- S H Eriksen
- Department of General Microbiology, Institute of Molecular Biology, University of Copenhagen, Solvgade 83H, DK-1307 K, Copenhagen, Denmark.
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32
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Hillenga DJ, Versantvoort HJ, Driessen AJ, Konings WN. Basic amino acid transport in plasma membrane vesicles of Penicillium chrysogenum. J Bacteriol 1996; 178:3991-5. [PMID: 8763922 PMCID: PMC178151 DOI: 10.1128/jb.178.14.3991-3995.1996] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The characteristics of the basic amino acid permease (system VI) of the filamentous fungus Penicillium chrysogenum were studied in plasma membranes fused with liposomes containing the beef heart mitochondrial cytochrome c oxidase. In the presence of reduced cytochrome c, the hybrid membranes accumulated the basic amino acids arginine and lysine. Inhibition studies with analogs revealed a narrow substrate specificity. Within the external pH range of 5.5 to 7.5, the transmembrane electrical potential (delta psi) functions as the main driving force for uphill transport of arginine, although a low level of uptake was observed when only a transmembrane pH gradient was present. It is concluded that the basic amino acid permease is a H+ symporter. Quantitative analysis of the steady-state levels of arginine uptake in relation to the proton motive force suggests a H+-arginine symport stoichiometry of one to one. Efflux studies demonstrated that the basic amino acid permease functions in a reversible manner.
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Affiliation(s)
- D J Hillenga
- Department of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, The Netherlands
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33
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De Smet I, Van Hoorde L, Vande Woestyne M, Christiaens H, Verstraete W. Significance of bile salt hydrolytic activities of lactobacilli. THE JOURNAL OF APPLIED BACTERIOLOGY 1995; 79:292-301. [PMID: 7592123 DOI: 10.1111/j.1365-2672.1995.tb03140.x] [Citation(s) in RCA: 192] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Bile salt hydrolase (BSH) activity was shown to be constitutive and substrate-specific: the BSH isogenic Lactobacillus plantarum wild type (LP80 WT) and BSH overproducing LP80 (pCBH1) strains preferentially hydrolysed glycodeoxycholic acid (GDCA), whereas the hamster Lact. animalis isolates H362 and H364 showed a higher affinity for taurodeoxycholic acid (TDCA). In viability studies in the presence of nutrients, it was demonstrated that GDCA exerted a higher toxicity than TDCA in a pH-dependent manner. This toxicity was inversely proportionate to the BSH activity level of the strains tested, indicating that BSH activity contributed towards bile salt resistance when appropriate nutrients were available. The high toxicity of GDCA relative to TDCA was suggested to be caused by their weak and strong acid properties respectively. It was therefore hypothesized that the protonated form of bile salts exhibited toxicity as it imported protons in the cell. This puts an energy-burden on BSH- lactobacilli which undergo intracellular acidification. BSH+ cells primarily protect themselves through the formation of the weaker DCA compound, which can help negate the pH-drop by recapturing and exporting the co-transported proton. However, since DCA is more toxic than its conjugated counterparts, an additional energy-dependent detoxification of DCA is suggested.
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Affiliation(s)
- I De Smet
- Laboratory of Microbial Ecology, Faculty of Agricultural and Applied Biological Sciences, University of Gent, Belgium
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34
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Hillenga DJ, Versantvoort H, van der Molen S, Driessen A, Konings WN. Penicillium chrysogenum Takes up the Penicillin G Precursor Phenylacetic Acid by Passive Diffusion. Appl Environ Microbiol 1995; 61:2589-95. [PMID: 16535072 PMCID: PMC1388490 DOI: 10.1128/aem.61.7.2589-2595.1995] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Penicillium chrysogenum utilizes phenylacetic acid as a side chain precursor in penicillin G biosynthesis. During industrial production of penicillin G, phenylacetic acid is fed in small amounts to the medium to avoid toxic side effects. Phenylacetic acid is taken up from the medium and intracellularly coupled to 6-aminopenicillanic acid. To enter the fungal cell, phenylacetic acid has to pass the plasma membrane. The process via which phenylacetic acid crosses the plasma membrane was studied in mycelia and liposomes. Uptake of phenylacetic acid by mycelium was nonsaturable, and the initial velocity increased logarithmically with decreasing external pH. Studies with liposomes demonstrated a rapid passive flux of the protonated species through liposomal membranes. These results indicate that phenylacetic acid passes the plasma membrane via passive diffusion of the protonated species. The rate of phenylacetic acid uptake at an external concentration of 3 mM is at least 200-fold higher than the penicillin production rate in the Panlabs P2 strain. In this strain, uptake of phenylacetic acid is not the rate-limiting step in penicillin G biosynthesis.
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35
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al-Sheddy IA, Fung DY, Kastner CL. Microbiology of fresh and restructured lamb meat: a review. Crit Rev Microbiol 1995; 21:31-52. [PMID: 7576150 DOI: 10.3109/10408419509113533] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Microbiology of meats has been a subject of great concern in food science and public health in recent years. Although many articles have been devoted to the microbiology of beef, pork, and poultry meats, much less has been written about microbiology of lamb meat and even less on restructured lamb meat. This article presents data on microbiology and shelf-life of fresh lamb meat; restructured meat products, restructured lamb meat products, bacteriology of restructured meat products, and important foodborne pathogens such as Salmonella, Escherichia coli O157:H7, and Listeria monocytogenes in meats and lamb meats. Also, the potential use of sodium and potassium lactates to control foodborne pathogens in meats and restructured lamb meat is reviewed This article should be of interest to all meat scientists, food scientists, and public health microbiologists who are concerned with the safety of meats in general and lamb meat in particular.
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Affiliation(s)
- I A al-Sheddy
- Department of Animal Sciences and Industry, Kansas State University, Manhattan 66506, USA
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36
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BRADFORD D, HUFFMAN D, EGBERT W, MIKEL W. Potassium Lactate Effects on Low-Fat Fresh Pork Sausage Chubs During Simulated Retail Distribution. J Food Sci 1993. [DOI: 10.1111/j.1365-2621.1993.tb06157.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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37
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BRADFORD DD, HUFFMAN DL, EGBERT WR, JONES WR. Low-Fat Fresh Pork Sausage Patty Stability in Refrigerated Storage with Potassiunn Lactate. J Food Sci 1993. [DOI: 10.1111/j.1365-2621.1993.tb04307.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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38
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EGBERT W, HUFFMAN D, BRADFORD D, JONES W. Properties of Low-Fat Ground Beef Containing Potassium Lactate During Aerobic Refrigerated Storage. J Food Sci 1992. [DOI: 10.1111/j.1365-2621.1992.tb11255.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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39
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LAMKEY JW, LEAK FW, TULEY WB, JOHNSON DD, WEST RL. Assessment of Sodium Lactate Addition to Fresh Pork Sausage. J Food Sci 1991. [DOI: 10.1111/j.1365-2621.1991.tb08015.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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40
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McDonald LC, Fleming HP, Hassan HM. Acid Tolerance of
Leuconostoc mesenteroides
and
Lactobacillus plantarum. Appl Environ Microbiol 1990; 56:2120-4. [PMID: 16348238 PMCID: PMC184570 DOI: 10.1128/aem.56.7.2120-2124.1990] [Citation(s) in RCA: 183] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In this study, we determined the internal cellular pH response of
Leuconostoc mesenteroides
and
Lactobacillus plantarum
to the external pH created by the microorganisms themselves or by lactic or acetic acids and their salts added to the growth medium. Growth of
Leuconostoc mesenteroides
stopped when its internal pH reached 5.4 to 5.7, and growth of
L. plantarum
stopped when its internal pH reached 4.6 to 4.8. Variation in growth medium composition or pH did not alter the growth-limiting internal pH reached by these microorganisms.
L. plantarum
maintained its pH gradient in the presence of either 160 mM sodium acetate or sodium lactate down to an external pH of 3.0 with either acid. In contrast, the ΔpH of
Leuconostoc mesenteroides
was zero at pH 4.0 with acetate and 5.0 with lactate. No differences were found between
d
-(−)- and
l
-(+)-lactic acid for the limiting internal pH for growth of either microorganism. The comparatively low growth-limiting internal pH and ability to maintain a pH gradient at high organic acid concentration may contribute to the ability of
L. plantarum
to terminate vegetable fermentations.
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Affiliation(s)
- L C McDonald
- Food Fermentation Laboratory, Agricultural Research Service, U.S. Department of Agriculture, and North Carolina Agricultural Research Service, Department of Food Science, North Carolina State University, Raleigh, North Carolina 27695-7624
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41
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Martínez-Blanco H, Reglero A, Rodriguez-Aparicio LB, Luengo JM. Purification and biochemical characterization of phenylacetyl-CoA ligase from Pseudomonas putida. A specific enzyme for the catabolism of phenylacetic acid. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(19)39262-2] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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42
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Warth AD. Effect of Benzoic Acid on Growth Yield of Yeasts Differing in Their Resistance to Preservatives. Appl Environ Microbiol 1988; 54:2091-5. [PMID: 16347720 PMCID: PMC202808 DOI: 10.1128/aem.54.8.2091-2095.1988] [Citation(s) in RCA: 81] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Yeasts grown in the presence of benzoic acid tolerated 40 to 100% higher benzoic acid concentrations than did those grown in the absence of weak-acid-type preservatives. They also accumulated less benzoate in the presence of glucose. In chemostat cultures, benzoic acid reduced growth yield and the rate of cell production but increased specific fermentation rates. Benzoate contents were lower than those required for equilibrium when cells were impermeable to benzoate anion. Intracellular pHs were maintained near neutrality. Between species, stimulation of fermentation was inversely related to preservation resistance but was unrelated to the maximum rate of fermentation. The results show that a major effect of benzoic acid on yeasts in the presence of an energy source is the energy requirement for the reduction in cytoplasmic benzoate concentration and maintenance of pH. This energy source is unavailable for growth, resulting in lower growth yields and rates. Resistant species may be less permeable to undissociated benzoic acid.
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Affiliation(s)
- A D Warth
- Division of Food Processing, Commonwealth Scientific and Industrial Research Organization, P.O. Box 52, North Ryde, New South Wales 2113, Australia
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43
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Warth A. Effect of nutrients and pH on the resistance of Zygosaccharomyces bailii to benzoic acid. Int J Food Microbiol 1986. [DOI: 10.1016/0168-1605(86)90003-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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44
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Ugalde U, Pitt D. Calcium uptake kinetics in relation to conidiation in submerged cultures of Penicillium cyclopium. ACTA ACUST UNITED AC 1986. [DOI: 10.1016/s0007-1536(86)80021-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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45
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Abstract
The wild-type strain and four DNA repair-deficient strains (uvrA6, uvrB5, recA56, and polA1) of Escherichia coli K-12 were treated with acetic acid, lactic acid, and p-aminobenzoic acid at pH 3.5 during their stationary phase of growth. All three acids were highly toxic to the polymerase-deficient strain. The greater sensitivity of the strain carrying the polA1 gene than its isogenic pol+ derivatives suggested that damage caused by acidity requires polA+ gene products for repair.
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46
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47
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Hunter DR, Segel IH. Evidence for two distinct intracellular pools of inorganic sulfate in Penicillium notatum. J Bacteriol 1985; 162:881-7. [PMID: 3997782 PMCID: PMC215857 DOI: 10.1128/jb.162.3.881-887.1985] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
A strain of Penicillium notatum unable to metabolize inorganic sulfate can accumulate sulfate internally to an apparent equilibrium concentration 10(5) greater than that remaining in the medium. The apparent Keq is near constant at all initial external sulfate concentrations below that which would eventually exceed the internal capacity of the cells. Under equilibrium conditions of zero net flux, external 35SO42- exchanges with internal, unlabeled SO42- at a rate consistent with the kinetic constants with the sulfate transport system. Efflux experiments demonstrated that sulfate occupies two distinct intracellular pools. Pool 1 is characterized by the rapid release of 35SO42- when the suspension of preloaded cells is adjusted to 10 mM azide at pH 8.4 (t 1/2, 0.38 min). 35SO42- in pool 1 also rapidly exchanges with unlabeled medium sulfate. Pool 2 is characterized by the slow release of 35SO42- induced by azide at pH 8.4 or unlabeled sulfate (t 1/2, 32 to 49 min). Early in the 35SO42- accumulation process, up to 78% of the total transported substrate is found in pool 1. At equilibrium, pool 1 accounts for only about 2% of the total accumulated 35SO42-. The kinetics of 35SO42- accumulation is consistent with the following sequential process: medium----pool 1----pool 2. Monensin (33 microns) accelerates the transfer of 35SO42- from pool 1 to pool 2. Valinomycin (0.2 microM) and tetraphenylboron- (1 mM) retard the transfer of 35SO42- from pool 1 to pool 2. At the concentrations used, neither of the ionophores nor tetraphenylboron- affect total 35SO42- uptake. Pool 2 may reside in a vacuole or other intracellular organelle. A model for the transfer of sulfate from pool 1 to pool 2 is presented.
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PRZYBYLSKI KS, BULLERMAN LB. INFLUENCE OF SORBIC ACID ON VIABILITY AND ATP CONTENT OF CONIDIA OF Aspergillus parasiticus. J Food Sci 1980. [DOI: 10.1111/j.1365-2621.1980.tb02618.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Chandler CJ, Segel IH. Mechanism of the antimicrobial action of pyrithione: effects on membrane transport, ATP levels, and protein synthesis. Antimicrob Agents Chemother 1978; 14:60-8. [PMID: 28693 PMCID: PMC352405 DOI: 10.1128/aac.14.1.60] [Citation(s) in RCA: 71] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Pyrithione is a general inhibitor of membrane transport processes in fungi. A brief preincubation of Penicillium mycelia with pyrithione resulted in a marked decrease in the activities of a variety of independently regulated transport systems, including those for inorganic sulfate, inorganic phosphate, methylamine (actually, the NH(4) (+) permease), choline-O-sulfate, glucose, l-methionine (a specific system), and several hydrophobic l-alpha-amino acids (the general amino acid permease). The degree of inhibition at any fixed pyrithione concentration and exposure time increased as the pH of the incubation medium was decreased. This result strongly suggests that the active species is the un-ionized molecule and that pyrithione acts by collapsing a transmembrane DeltapH driving force. The degree of transport inhibition caused by a given concentration of pyrithione increased with increasing time of exposure to the inhibitor. However, exposure time and pyrithione concentration were not reciprocally related. At "low" pyrithione concentrations, transport inhibition plateaued at some finite value. This observation suggests that the fungi can detoxify low levels of the inhibitor. The concentration of pyrithione required for a given degree of growth inhibition increased as the experimental mycelial density increased. This phenomenon was consistent with the suggestion that the fungi are capable of inactivating pyrithione.
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