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Hoang MD, Riessner S, Oropeza Vargas JE, von den Eichen N, Heins AL. Influence of Varying Pre-Culture Conditions on the Level of Population Heterogeneity in Batch Cultures with an Escherichia coli Triple Reporter Strain. Microorganisms 2023; 11:1763. [PMID: 37512936 PMCID: PMC10384452 DOI: 10.3390/microorganisms11071763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 06/26/2023] [Accepted: 06/29/2023] [Indexed: 07/30/2023] Open
Abstract
When targeting robust, high-yielding bioprocesses, phenomena such as population heterogeneity have to be considered. Therefore, the influence of the conditions which the cells experience prior to the main culture should also be evaluated. Here, the influence of a pre-culture medium (complex vs. minimal medium), optical density for inoculation of the main culture (0.005, 0.02 and 0.0125) and harvest time points of the pre-culture in exponential growth phase (early, mid and late) on the level of population heterogeneity in batch cultures of the Escherichia coli triple reporter strain G7BL21(DE3) in stirred-tank bioreactors was studied. This strain allows monitoring the growth (rrnB-EmGFP), general stress response (rpoS-mStrawberry) and oxygen limitation (nar-TagRFP657) of single cells through the expression of fluorescent proteins. Data from batch cultivations with varying pre-culture conditions were analysed with principal component analysis. According to fluorescence data, the pre-culture medium had the largest impact on population heterogeneities during the bioprocess. While a minimal medium as a pre-culture medium elevated the differences in cellular growth behaviour in the subsequent batch process, a complex medium increased the general stress response and led to a higher population heterogeneity. The latter was promoted by an early harvest of the cells with low inoculation density. Seemingly, nar-operon expression acted independently of the pre-culture conditions.
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Affiliation(s)
- Manh Dat Hoang
- Chair of Biochemical Engineering, TUM School of Engineering and Design, Technical University of Munich, 85748 Garching, Germany
| | - Sophi Riessner
- Chair of Biochemical Engineering, TUM School of Engineering and Design, Technical University of Munich, 85748 Garching, Germany
| | - Jose Enrique Oropeza Vargas
- Chair of Biochemical Engineering, TUM School of Engineering and Design, Technical University of Munich, 85748 Garching, Germany
| | - Nikolas von den Eichen
- Chair of Biochemical Engineering, TUM School of Engineering and Design, Technical University of Munich, 85748 Garching, Germany
| | - Anna-Lena Heins
- Chair of Biochemical Engineering, TUM School of Engineering and Design, Technical University of Munich, 85748 Garching, Germany
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2
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Competition between Starter Cultures and Wild Microbial Population in Sausage Fermentation: A Case Study Regarding a Typical Italian Salami ( Ventricina). Foods 2021; 10:foods10092138. [PMID: 34574248 PMCID: PMC8467601 DOI: 10.3390/foods10092138] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 08/13/2021] [Accepted: 09/07/2021] [Indexed: 01/04/2023] Open
Abstract
The work reports a case study describing how the competition wild microflora vs. starter cultures affects the final product characteristics. This study regards an industrial lot of Ventricina, an Italian long-ripened traditional fermented sausages, produced using starter cultures. After ripening, some relevant organoleptic defects (off-odour, crust formation) were observed. Therefore, analyses were carried out in the inner and outer sausage section to explain this phenomenon. Microbiological analyses indicated a high meat batter contamination and metagenomic analyses evidenced the inability of LAB starter cultures to lead the fermentation process. The results of this not controlled fermentation were the accumulation of high levels of biogenic amines (including histamine) and the formation of a volatile profile different if compared with similar products. Indeed, the volatilome analysis revealed unusually high amounts of molecules such as isovaleric acid, propanoic acid, 1-propanol, which can be responsible for off-odours. This study demonstrated that starter culture use needs to be modulated in relation to production parameters to avoid safety and organoleptic concerns.
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Adadi P, Barakova NV, Krivoshapkina EF. Scientific approaches to improving artisan methods of producing local food condiments in Ghana. Food Control 2019. [DOI: 10.1016/j.foodcont.2019.06.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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4
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Exploring the metabolic heterogeneity of coagulase-negative staphylococci to improve the quality and safety of fermented meats: a review. Int J Food Microbiol 2017; 247:24-37. [DOI: 10.1016/j.ijfoodmicro.2016.05.021] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 03/15/2016] [Accepted: 05/15/2016] [Indexed: 12/16/2022]
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Fernández-Diez A, Caro I, Castro A, Salvá BK, Ramos DD, Mateo J. Partial Fat Replacement by Boiled Quinoa on the Quality Characteristics of a Dry-Cured Sausage. J Food Sci 2016; 81:C1891-8. [DOI: 10.1111/1750-3841.13393] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 05/07/2016] [Accepted: 06/17/2016] [Indexed: 11/27/2022]
Affiliation(s)
- Ana Fernández-Diez
- Depto. de Higiene y Tecnología de los Alimentos, Facultad de Veterinaria, Campus Vegazana s/n; Univ. de León; 24007 León Spain
| | - Irma Caro
- Depto. de Higiene y Tecnología de los Alimentos, Facultad de Veterinaria, Campus Vegazana s/n; Univ. de León; 24007 León Spain
| | - Amaya Castro
- Depto. de Higiene y Tecnología de los Alimentos, Facultad de Veterinaria, Campus Vegazana s/n; Univ. de León; 24007 León Spain
| | - Bettit K. Salvá
- Depto. de Tecnología de Alimentos y Productos Agropecuarios; Univ. Nacional Agraria La Molina; Av. La Molina s/n, Lima 12 Peru
| | - Daphne D. Ramos
- Facultad de Medicina Veterinaria; Univ. Nacional Mayor de San Marcos; Avenida Circunvalación Cdra 28 s/n San Borja Lima Peru
| | - Javier Mateo
- Depto. de Higiene y Tecnología de los Alimentos, Facultad de Veterinaria, Campus Vegazana s/n; Univ. de León; 24007 León Spain
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Stavropoulou DA, Borremans W, De Vuyst L, De Smet S, Leroy F. Amino acid conversions by coagulase-negative staphylococci in a rich medium: Assessment of inter- and intraspecies heterogeneity. Int J Food Microbiol 2015; 212:34-40. [PMID: 25991555 DOI: 10.1016/j.ijfoodmicro.2015.04.048] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 04/24/2015] [Accepted: 04/29/2015] [Indexed: 11/19/2022]
Abstract
The ability of coagulase-negative staphylococci (CNS) to convert amino acids into volatile compounds and biogenic amines was investigated after 24h and 48 h of incubation in a rich medium (brain heart infusion). Volatile compounds were measured with static-headspace gas chromatography and mass spectrometry (SH-GC-MS); biogenic amine measurements were carried out with a newly developed method based on ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS). In total, 56 CNS strains from five different species were used, namely Staphylococcus carnosus, Staphylococcus epidermidis, Staphylococcus equorum, Staphylococcus saprophyticus, and Staphylococcus xylosus. With respect to the production of volatile compounds, the leucine-derived 3-methyl butanol was produced over time by most CNS strains, up to 52 μM for S. xylosus W1-1 after 48 h of incubation. The average production by strains of S. xylosus was significantly higher than for strains of S. carnosus, whereas strains of S. epidermidis turned out to be poor producers. Yet, differences between species were blurred to a large degree because of the high strain variability. A few strains also produced 3-methyl butanal on top of the amount that was already present in the medium background, although most CNS led to a decrease of this compound. Concerning biogenic amines, the average total concentrations per species remained below 100 μM after 48 h of incubation. The most abundant variant was 2-phenylethylamine (PEA), especially within S. carnosus (average of 65 μM after 48 h of incubation). Yet, some individual strains were able to produce higher concentrations, as found for the PEA production of 295 μM by S. epidermidis ATCC 12228 after 48 h of incubation. The insights obtained during this study indicate heterogeneity and are of importance in view of both starter culture development and the evaluation of a spontaneously established CNS microbiota in artisan-type meat fermentations.
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Affiliation(s)
- Despoina Angeliki Stavropoulou
- Research Group of Industrial Microbiology and Food Biotechnology (IMDO), Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Wim Borremans
- Research Group of Industrial Microbiology and Food Biotechnology (IMDO), Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Luc De Vuyst
- Research Group of Industrial Microbiology and Food Biotechnology (IMDO), Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Stefaan De Smet
- Laboratory for Animal Nutrition and Animal Product Quality, Department of Animal Production, Ghent University, Melle, Belgium
| | - Frédéric Leroy
- Research Group of Industrial Microbiology and Food Biotechnology (IMDO), Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium.
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Nitrite promotes protein carbonylation and Strecker aldehyde formation in experimental fermented sausages: Are both events connected? Meat Sci 2014; 98:665-72. [DOI: 10.1016/j.meatsci.2014.06.017] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 06/13/2014] [Accepted: 06/16/2014] [Indexed: 11/18/2022]
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Olesen PT, Meyer AS, Stahnke LH. Generation of flavour compounds in fermented sausages-the influence of curing ingredients, Staphylococcus starter culture and ripening time. Meat Sci 2012; 66:675-87. [PMID: 22060878 DOI: 10.1016/s0309-1740(03)00189-x] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2002] [Revised: 05/19/2003] [Accepted: 06/15/2003] [Indexed: 10/27/2022]
Abstract
The volatile profiles of fermented sausages made with either Staphylococcus xylosus or Staphylococcus carnosus starter cultures were studied with regard to the influence of salt concentration, ripening time and three different combinations of curing ingredients-nitrate, nitrite or nitrite/ascorbate. Emphasis was laid on volatile compounds originating from degradation of branched-chain amino acids. Volatile compounds were collected using dynamic headspace sampling and were identified by gas chromatography/mass spectrometry (GC/MS). Development in water activity, water loss and pH was monitored throughout maturation. Curing salts had a pronounced effect on the level of volatile compounds. In particular, curing with nitrate instead of nitrite resulted in a striking difference. Generally, nitrate increased the level of volatile compounds compared to nitrite, whereas ascorbate had only a small influence. The concentration level of NaCl had a considerable effect on the amount of volatile compounds but the effect was highly related to the ripening stage. Most compounds, but not all, increased in concentration as ripening proceeded. Major differences in the development of volatile compounds were observed depending on whether S. xylosus or S. carnosus were used as starter culture. In particular the effects of nitrate was much more predominant in the sausages made with S. carnosus than S.xylosus.
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Affiliation(s)
- Pelle Thonning Olesen
- BioCentrum-DTU, Technical University of Denmark, build. 221, DK-2800 Kgs. Lyngby, Denmark
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Tabanelli G, Coloretti F, Chiavari C, Grazia L, Lanciotti R, Gardini F. Effects of starter cultures and fermentation climate on the properties of two types of typical Italian dry fermented sausages produced under industrial conditions. Food Control 2012. [DOI: 10.1016/j.foodcont.2012.01.049] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Metabolism of amino acids, dipeptides and tetrapeptides by Lactobacillus sakei. Food Microbiol 2012; 29:215-23. [DOI: 10.1016/j.fm.2011.07.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Revised: 07/14/2011] [Accepted: 07/14/2011] [Indexed: 11/19/2022]
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11
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Holm E, Schäfer A, Skov T, Koch A, Petersen M. Identification of chemical markers for the sensory shelf-life of saveloy. Meat Sci 2012; 90:314-22. [DOI: 10.1016/j.meatsci.2011.07.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Revised: 07/21/2011] [Accepted: 07/23/2011] [Indexed: 10/17/2022]
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12
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Freiding S, Gutsche KA, Ehrmann MA, Vogel RF. Genetic screening of Lactobacillus sakei and Lactobacillus curvatus strains for their peptidolytic system and amino acid metabolism, and comparison of their volatilomes in a model system. Syst Appl Microbiol 2011; 34:311-20. [DOI: 10.1016/j.syapm.2010.12.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Revised: 12/15/2010] [Accepted: 12/17/2010] [Indexed: 11/25/2022]
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13
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Sun W, Zhao Q, Zhao H, Zhao M, Yang B. Volatile compounds of Cantonese sausage released at different stages of processing and storage. Food Chem 2010. [DOI: 10.1016/j.foodchem.2009.12.031] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Udomsil N, Rodtong S, Tanasupawat S, Yongsawatdigul J. Proteinase-producing halophilic lactic acid bacteria isolated from fish sauce fermentation and their ability to produce volatile compounds. Int J Food Microbiol 2010; 141:186-94. [PMID: 20541276 DOI: 10.1016/j.ijfoodmicro.2010.05.016] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2010] [Revised: 05/10/2010] [Accepted: 05/14/2010] [Indexed: 11/26/2022]
Abstract
Halophilic lactic acid bacteria were isolated from fish sauce mashes fermented at 1 to 12 months. Seven out of sixty-four isolates were selected according to their proteolytic activity and growth at 25% NaCl for characterization and investigation of volatile compound production. All selected isolates were Gram-positive cocci with pairs/tetrads and grew at 0-25% NaCl, pH 4.5-9.0. Results of 16S rRNA gene sequence analysis showed 99% homology to Tetragenococcus halophilus ATCC 33315. The restriction fragment length polymorphism (RFLP) patterns of all isolates were also similar to those of T. halophilus ATCC 33315. These isolates were, thus, identified as T. halophilus. All isolates hydrolyzed fish protein in the medium containing 25% NaCl. Intracellular aminopeptidase of 7 isolates exhibited the highest activity of 2.85-3.67 U/ml toward Ala-p-nitroanilide (Ala-pNA). T.halophilus strains MS33 and M11 showed the highest alanyl aminopeptidase activity (P<0.05), and produced histamine in mGYP broth containing 5 and 25% NaCl in the level of 6.62-22.55 and 13.14-20.39 mg/100ml, respectively. Predominant volatile compounds of fish broth containing 25% NaCl inoculated with T. halophilus MS33 and MRC5-5-2 were 1-propanol, 2-methylpropanal, and benzaldehyde, corresponding to major volatile compounds in fish sauce. T.halophilus appeared to play an important role in volatile compound formation during fish sauce fermentation.
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Affiliation(s)
- Natteewan Udomsil
- Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima, Thailand
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Pérez-Palacios T, Ruiz J, Martín D, Grau R, Antequera T. Influence of pre-cure freezing on the profile of volatile compounds during the processing of Iberian hams. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2010; 90:882-890. [PMID: 20355126 DOI: 10.1002/jsfa.3899] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
BACKGROUND This work was designed to study the effect of pre-cure freezing of raw thighs from Iberian pigs on the profile of volatile compounds during the processing of hams. RESULTS Generation of volatile compounds during Iberian ham processing was similar in both pre-cure frozen and refrigerated hams, the main differences being at the final stage. The levels of 2-methylbutanal, 2-methyl-1-butanol, 2,3-butanediol and 2-heptanol were significantly higher in dry-cured hams that were pre-cure frozen than in refrigerated ones, whereas the content of most detected esters was statistically lower in pre-cure frozen than in refrigerated hams. CONCLUSION The effect of pre-cure freezing of Iberian ham on the profile of volatile compounds during ripening was not remarkable. Few differences were found in the final product, which would not greatly modify the aroma and flavour features of the dry-cured hams.
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Affiliation(s)
- Trinidad Pérez-Palacios
- Food Science, School of Veterinary Sciences, University of Extremadura, 10071 Cáceres, Spain.
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Hettinga K, van Valenberg H, Lam TG, van Hooijdonk A. The influence of incubation on the formation of volatile bacterial metabolites in mastitis milk. J Dairy Sci 2009; 92:4901-5. [DOI: 10.3168/jds.2008-1818] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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17
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Smit BA, Engels WJM, Smit G. Branched chain aldehydes: production and breakdown pathways and relevance for flavour in foods. Appl Microbiol Biotechnol 2008; 81:987-99. [PMID: 19015847 PMCID: PMC7419363 DOI: 10.1007/s00253-008-1758-x] [Citation(s) in RCA: 145] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2008] [Revised: 10/16/2008] [Accepted: 10/18/2008] [Indexed: 11/28/2022]
Abstract
Branched aldehydes, such as 2-methyl propanal and 2- and 3-methyl butanal, are important flavour compounds in many food products, both fermented and non-fermented (heat-treated) products. The production and degradation of these aldehydes from amino acids is described and reviewed extensively in literature. This paper reviews aspects influencing the formation of these aldehydes at the level of metabolic conversions, microbial and food composition. Special emphasis was on 3-methyl butanal and its presence in various food products. Knowledge gained about the generation pathways of these flavour compounds is essential for being able to control the formation of desired levels of these aldehydes.
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Affiliation(s)
- Bart A Smit
- Campina Innovation, Nieuwe Kanaal 7C, 6709PA Wageningen, The Netherlands
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Misharina TA, Terenina MB, Krikunova NI, Khankhalaeva IA, Khamagaeva IS, Nikiforova LL. The influence of starter cultures on the formation of volatile compounds in dry smoked sausages. APPL BIOCHEM MICRO+ 2008. [DOI: 10.1134/s0003683808050165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Yongsawatdigul J, Rodtong S, Raksakulthai N. Acceleration of Thai fish sauce fermentation using proteinases and bacterial starter cultures. J Food Sci 2008; 72:M382-90. [PMID: 18034732 DOI: 10.1111/j.1750-3841.2007.00532.x] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A means to accelerate fish sauce fermentation without adversely affecting fish sauce quality was investigated. Starter cultures prepared from Virgibacillus sp. SK33, Virgibacillus sp. SK37, and Staphylococcus sp. SK1-1-5 were added separately to anchovy that was hydrolyzed by 0.25% Alcalase at 60 degrees C for 2 h followed by 0.5% Flavourzyme at 50 degrees C for 4 h. The mixtures were then adjusted to contain 25% solar salt and incubated at 35 degrees C for 4 mo. alpha-Amino contents of all inoculated samples were higher than the control (without the addition of starter culture) during the course of fermentation. After 4-mo fermentation, the samples inoculated with Staphylococcus sp. SK1-1-5 contained the highest alpha-amino content of 733.37 +/- 13.89 mM while that of the control was 682.67 +/- 3.33 mM. Amino acid profiles of inoculated samples showed similar patterns to that of commercial product fermented for 12 mo, with glutamic, aspartic, and lysine being predominant amino acids. Virgibacillus sp. SK33 appeared to decrease histamine content of fish sauce by 50% when compared to the control. Volatile compounds analyzed by GC-MS of all inoculated samples fermented for 4 mo exhibited a similar pattern to those of the 12-mo-old commercial product. Samples inoculated with Staphylococcus sp. SK1-1-5 produced higher levels of volatile fatty acids and showed similar sensory characteristics to the commercial fish sauce fermented for 12 mo. Staphylococcus sp. SK1-1-5 is a potential strain that can be applied to produce fish sauce with overall sensory characteristics of traditional fish sauce in shorter time.
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Affiliation(s)
- J Yongsawatdigul
- School of Food Technology at Suranaree Univ. of Technology, Nakhon Ratchasima, Thailand
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Fukami K, Funatsu Y, Kawasaki K, Watabe S. Improvement of Fish-sauce Odor by Treatment with Bacteria Isolated from the Fish-sauce Mush (Moromi) Made from Frigate Mackerel. J Food Sci 2006. [DOI: 10.1111/j.1365-2621.2004.tb15514.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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21
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Leroy F, Verluyten J, De Vuyst L. Functional meat starter cultures for improved sausage fermentation. Int J Food Microbiol 2006; 106:270-85. [PMID: 16213053 DOI: 10.1016/j.ijfoodmicro.2005.06.027] [Citation(s) in RCA: 346] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2004] [Accepted: 06/28/2005] [Indexed: 10/25/2022]
Abstract
Starter cultures that initiate rapid acidification of the raw meat batter and that lead to a desirable sensory quality of the end-product are used for the production of fermented sausages. Recently, the use of new, functional starter cultures with an industrially or nutritionally important functionality is being explored. Functional starter cultures offer an additional functionality compared to classical starter cultures and represent a way of improving and optimising the sausage fermentation process and achieving tastier, safer, and healthier products. Examples include microorganisms that generate aroma compounds, health-promoting molecules, bacteriocins or other antimicrobials, contribute to cured meat colour, possess probiotic qualities, or lack negative properties such as the production of biogenic amines and toxic compounds. The vast quantity of artisan fermented sausages from different origins represents a treasure chest of biodiversity that can be exploited to create such functional starter cultures.
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Affiliation(s)
- Frédéric Leroy
- Research Group of Industrial Microbiology, Fermentation Technology and Downstream Processing (IMDO), Department of Applied Biological Sciences, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium
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Leroy F, Lievens K, De Vuyst L. Interactions of meat-associated bacteriocin-producing Lactobacilli with Listeria innocua under stringent sausage fermentation conditions. J Food Prot 2005; 68:2078-84. [PMID: 16245710 DOI: 10.4315/0362-028x-68.10.2078] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The kinetics of the antilisterial effect of meat-associated lactobacilli on Listeria innocua LMG 13568 were investigated during laboratory batch fermentations. During these fermentations, which were performed in a liquid meat simulation medium, a combination of process factors typical for European-style sausage fermentations was applied, such as a temperature of 20 degrees C and a representative pH and salting profile. Two bacteriocin-producing sausage isolates (Lactobacillus sakei CTC 494 and Lactobacillus curvatus LTH 1174), which have already proven efficacy in sausage trials, and one nonbacteriocinogenic, industrial strain (Lactobacillus sakei I), were evaluated. Staphylococcus carnosus 833 was included in the experiment because of its role in flavor and color development. When grown as a monoculture or upon cocultivation with L. sakei I and S. carnosus 833, L. innocua LMG 13568 developed slightly, despite the stress of low temperature, pH, lactic acid, salt, and nitrite. In contrast, when either of the bacteriocin producers was used, the L. innocua LMG 13568 population was rapidly inactivated with more than 3 log CFU ml(-1) after 2 days of fermentation. A bacteriocin-tolerant L. innocua LMG 13568 subpopulation (4 X 10(-4)) remained after bacteriocin inactivation. Thus, when the initial level of L. innocua LMG 13568 equaled 3 log CFU ml(-1), all cells were inactivated and no bacteriocin-tolerant cells were detected, even after 7 days of incubation. S. carnosus was not inactivated by the Lactobacillus bacteriocins and displayed slight growth.
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Affiliation(s)
- Frédéric Leroy
- Research Group of Industrial Microbiology, Fermentation Technology and Downstream Processing (IMDO), Department of Applied Biological Sciences, Vrije Universiteit Brussel (VUB), B-1050 Brussels, Belgium
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Villas-Bôas SG, Mas S, Akesson M, Smedsgaard J, Nielsen J. Mass spectrometry in metabolome analysis. MASS SPECTROMETRY REVIEWS 2005; 24:613-46. [PMID: 15389842 DOI: 10.1002/mas.20032] [Citation(s) in RCA: 356] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
In the post-genomic era, increasing efforts have been made to describe the relationship between the genome and the phenotype in cells and organisms. It has become clear that even a complete understanding of the state of the genes, messages, and proteins in a living system does not reveal its phenotype. Therefore, researchers have started to study the metabolome (or the metabolic complement of functional genomics). Within this context, mass spectrometry (MS) has increasingly occupied a central position in the methodologies developed for determination of the metabolic state. This review is mainly focused on the status of MS in the metabolome field, trying to direct the reader to the main approaches for analysis of metabolites, reviewing basic methodologies in sample preparation, and the most recent MS techniques introduced. Apart from the description of the different methods, this review will try to state a general comparison between the several different techniques that involve MS and metabolite analysis, and will highlight their limitations and preferred applicability.
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Affiliation(s)
- Silas G Villas-Bôas
- Center for Microbial Biotechnology, BioCentrum-DTU, Technical University of Denmark, Building 223, DK-2800 Kgs. Lyngby, Denmark
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Wu S, Zorn H, Krings U, Berger RG. Characteristic volatiles from young and aged fruiting bodies of wild Polyporus sulfureus (Bull.:Fr.) Fr. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2005; 53:4524-8. [PMID: 15913320 DOI: 10.1021/jf0478511] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The volatile compounds of fresh fruiting bodies of wild Polyporus sulfureus (Bull.:Fr.) Fr. growing on oak trees were isolated by continuous liquid-liquid extraction (CLLE) and investigated by high-resolution gas chromatography-mass spectrometry (HRGC-MS) on two GC columns of different polarity (DB-5 and ZB-WAX), and by gas chromatography-olfactometry (GC-O). A total of 40 major volatile compounds from the young samples were identified and semiquantified. Five odorous compounds were determined to be responsible for the characteristic flavor of young Polyporus sulfureus: 1-octen-3-one, 1-octen-3-ol, 3-methylbutanoic acid, phenylethanol, and phenylacetic acid. Four volatiles investigated by GC-O and detected by GC-MS were determined as the characteristic odorants of aged species: 2-methylpropanoic acid, butanoic acid, 3-methylbutanoic acid, and phenylacetic acid. The comparative results revealed that the volatile composition of the fruiting bodies even from the same fungal species may greatly vary with its host, location, and age.
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Affiliation(s)
- Shimin Wu
- Zentrum Angewandte Chemie, Institut für Lebensmittelchemie, Universität Hannover, Wunstorfer Strasse 14, D-30453 Hannover, Germany
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25
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Beck HC. Branched-chain fatty acid biosynthesis in a branched-chain amino acid aminotransferase mutant of Staphylococcus carnosus. FEMS Microbiol Lett 2005; 243:37-44. [PMID: 15667998 DOI: 10.1016/j.femsle.2004.11.041] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2004] [Revised: 11/17/2004] [Accepted: 11/21/2004] [Indexed: 10/26/2022] Open
Abstract
Fatty acid biosynthesis by a mutant strain of Staphylococcus carnosus deficient in branched-chain amino acid aminotransferase (IlvE) activity was analysed. This mutant was unable to produce the appropriate branched-chain alpha-ketoacid precursors for branched-chain fatty acid biosynthesis from the amino acids valine, isoleucine, and leucine, and required the short branched chain acids 2-methylbutanoic acid or 2-methylpropanoic acid for growth in a defined medium. The isoleucine related metabolites, alpha-keto-beta-methylvaleric acid and 2-methylbutanal also served as growth factors. Growth in rich medium and growth in defined medium supplemented with 2-methylpropanoic acid lead to extensive alteration of the fatty acid composition in the cell membrane. In rich medium, a change from 51.7% to 17.1% anteiso-C15:0, and from 3.6% to 33.9% iso-C14:0 fatty acids as compared to the wild-type strain was observed. Despite the deficiency in IlvE activity, the mutant strain was still able to produce the short chain carboxylic acids, 3-methylbutanoic acid and 2-methylpropanoic acid when cultivated in rich medium. Supplementation experiments employing deuterated glucose induced the valine biosynthetic pathway for 2-methylpropanoic acid production, revealing that the IlvE protein plays an important, but not essential role in the biosynthesis of branched-chain fatty acids and secondary metabolites in S. carnosus.
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Affiliation(s)
- Hans C Beck
- Danish Technological Institute, Holbergsvej 10, DK-6000 Kolding, Denmark.
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Tjener K, Stahnke LH, Andersen L, Martinussen J. The pH-unrelated influence of salt, temperature and manganese on aroma formation by Staphylococcus xylosus and Staphylococcus carnosus in a fermented meat model system. Int J Food Microbiol 2004; 97:31-42. [PMID: 15527916 DOI: 10.1016/j.ijfoodmicro.2004.04.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2003] [Revised: 12/22/2003] [Accepted: 04/04/2004] [Indexed: 11/23/2022]
Abstract
The influence of manganese (0.01-0.1-1.0 microg/g), temperature (15-24 degrees C) and salt (3-4% w/w) on volatile formation in model minces inoculated with Pediococcus pentosaceus and either Staphylococcus xylosus or Staphylococcus carnosus was studied in a full factorial experiment. In order to study the direct, pH-unrelated effect of the parameters, data were analysed by use of multiple linear regression and partial least-squares regression both before and after transformation of the volatile responses into pH-orthogonal (pH-unrelated) responses. By using the pH-orthogonalised data, the overall interpretability of the experiment was increased, and new cause-and-effect relations were suggested. Approximately 50% of the total variance in volatile levels was due to differences caused by S. xylosus and S. carnosus, and another 30% was related to differences in pH development. The remaining 20% covered pH-orthogonal effects of manganese, temperature and salt plus the experimental noise. From this, it was concluded that most of the variation in volatile profiles caused by manganese, temperature and salt was in fact directly or indirectly caused by changes in lactic acid bacterial activity and pH.
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Affiliation(s)
- Karsten Tjener
- Chr. Hansen A/S, Bøge Allé 10-12, DK-2970, Hørsholm, Denmark.
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Olesen PT, Stahnke LH, Talon R. Effect of ascorbate, nitrate and nitrite on the amount of flavour compounds produced from leucine by Staphylococcus xylosus and Staphylococcus carnosus. Meat Sci 2004; 68:193-200. [DOI: 10.1016/j.meatsci.2004.02.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2003] [Revised: 02/12/2004] [Accepted: 02/17/2004] [Indexed: 10/26/2022]
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de Vos Petersen C, Beck HC, Lauritsen FR. On-line monitoring of important organoleptic methyl-branched aldehydes during batch fermentation of starter culture Staphylococcus xylosus reveal new insight into their production in a model fermentation. Biotechnol Bioeng 2004; 85:298-305. [PMID: 14748085 DOI: 10.1002/bit.10885] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A small fermentor (55 mL) was directly interfaced to a membrane inlet mass spectrometer for continuous on-line monitoring of oxygen and volatile metabolites during batch fermentations of the starter culture Staphylococcus xylosus. Using this technique, we were able to correlate production of the very important flavor compounds 2-methylbutanal, 3-methylbutanal, and 2-methylpropanal with various growth conditions. We found that the aldehydes were present in the culture broth only as transient metabolites. They were produced in the exponential growth phase, reached a maximum concentration when the culture became anaerobic, and then they rapidly disappeared from the culture medium. This general pattern was observed for three different strains of S. xylosus and S. carnosus. Small amounts of inoculum or increased exposure to oxygen were found to favor production of the aldehydes as a result of a longer aerobic growth period. Growing S. xylosus under conditions resembling those in a fermented sausage revealed that NaCl (5%) increased aldehyde production considerably, whereas KNO(3) (0.03%) or NaNO(2) (0.03%) had little effect. A lowering of pH from 7.2 to 6.0 reduced cell density, but had a minor affect on aldehyde production.
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Affiliation(s)
- Christian de Vos Petersen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark Odense, Campusvej 5230, DK-5230 Odense M, Denmark
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29
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Beck HC, Hansen AM, Lauritsen FR. Catabolism of leucine to branched-chain fatty acids in Staphylococcus xylosus. J Appl Microbiol 2004; 96:1185-93. [PMID: 15078537 DOI: 10.1111/j.1365-2672.2004.02253.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS Staphylococcus xylosus is an important starter culture in the production of flavours from the branched-chain amino acids leucine, valine and isoleucine in fermented meat products. The sensorially most important flavour compounds are the branched-chain aldehydes and acids derived from the corresponding amino acids and this paper intends to perspectivate these flavour compounds in the context of leucine metabolism. METHODS AND RESULTS GC and GC/MS analysis combined with stable isotope labelling was used to study leucine catabolism. This amino acid together with valine and isoleucine was used as precursors for the production of branched-chain fatty acids for cell membrane biosynthesis during growth. A 83.3% of the cellular fatty acids were branched. The dominating fatty acid was anteiso-C(15:0) that constituted 55% of the fatty acids. A pyridoxal 5'-phosphate and alpha-ketoacid dependent reaction catalysed the deamination of leucine, valine and isoleucine into their corresponding alpha-ketoacids. As alpha-amino group acceptor alpha-keto-beta-methylvaleric acid and alpha-ketoisovaleric acid was much more efficient than alpha-ketoglutarate. The sensorially and metabolic key intermediate on the pathway to the branched-chain fatty acids, 3-methylbutanoic acid was produced from leucine at the onset of the stationary growth phase and then, when the growth medium became scarce in leucine, from the oxidation of glucose via pyruvate. CONCLUSIONS This paper demonstrates that the sensorially important branched-chain aldehydes and acids are important intermediates on the metabolic route leading to branched-chain fatty acids for cell membrane biosynthesis. SIGNIFICANCE AND IMPACT OF THE STUDY The metabolic information obtained is extremely important in connection with a future biotechnological design of starter cultures for production of fermented meat.
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Affiliation(s)
- H C Beck
- Celcom, Department of Biochemistry and Molecular Biology, University of Southern Denmark-Odense University, Odense M, Denmark.
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30
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Thonning Olesen P, Stahnke LH. The influence of environmental parameters on the catabolism of branched-chain amino acids by Staphylococcus xylosus and Staphylococcus carnosus. Food Microbiol 2004. [DOI: 10.1016/s0740-0020(03)00048-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Sunesen L, Trihaas J, Stahnke L. Volatiles in a sausage surface model-influence of Penicillium nalgiovense, Pediococcus pentosaceus, ascorbate, nitrate and temperature. Meat Sci 2004; 66:447-56. [DOI: 10.1016/s0309-1740(03)00133-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2001] [Revised: 05/20/2003] [Accepted: 05/29/2003] [Indexed: 10/27/2022]
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32
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Tjener K, Stahnke LH, Andersen L, Martinussen J. A fermented meat model system for studies of microbial aroma formation. Meat Sci 2004; 66:211-8. [DOI: 10.1016/s0309-1740(03)00093-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2002] [Revised: 04/08/2003] [Accepted: 04/15/2003] [Indexed: 11/26/2022]
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33
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Olesen PT, Stahnke LH. The influence of precultivation parameters on the catabolism of branched-chain amino acids by Staphylococcus xylosus and Staphylococcus carnosus. Food Microbiol 2003. [DOI: 10.1016/s0740-0020(03)00042-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Larrouture-Thiveyrat C, Montel MC. Effects of environmental factors on leucine catabolism by Carnobacterium piscicola. Int J Food Microbiol 2003; 81:177-84. [PMID: 12485743 DOI: 10.1016/s0168-1605(02)00227-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The metabolites from leucine degradation are involved in dry fermented sausage aroma. The catabolism of leucine by a strain of Carnobacterium piscicola was studied directly in the growth medium with 3H-labelled leucine to investigate the effect of five parameters: phase of growth, pH, oxygen, glucose and alpha-ketoisocaproic acid. Resting cells (RC) were also incubated with 3H-labelled leucine. The radioactive metabolites from leucine catabolism were analysed by high performance liquid chromatography (HPLC). At pH 5.4 and 7.2, the main metabolites detected were 3-methyl butanal, 3-methyl butanol and alpha-ketoisocaproic acid. At pH 6.5, the leucine catabolism was maximum and was characterised by a high production of 3-methyl butanoic acid. Leucine catabolism was most important during the exponential phase of growth. The addition of alpha-ketoisocaproic acid at 1%, glucose at levels of 0.5% to 2% and shaking of the growth medium increased leucine catabolism.
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Madsen SM, Beck HC, Ravn P, Vrang A, Hansen AM, Israelsen H. Cloning and inactivation of a branched-chain-amino-acid aminotransferase gene from Staphylococcus carnosus and characterization of the enzyme. Appl Environ Microbiol 2002; 68:4007-14. [PMID: 12147502 PMCID: PMC124023 DOI: 10.1128/aem.68.8.4007-4014.2002] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Staphylococcus carnosus and Staphylococcus xylosus are widely used as aroma producers in the manufacture of dried fermented sausages. Catabolism of branched-chain amino acids (BCAAs) by these strains contributes to aroma formation by production of methyl-branched aldehydes and carboxy acids. The first step in the catabolism is most likely a transamination reaction catalyzed by BCAA aminotransferases (IlvE proteins). In this study, we cloned the ilvE gene from S. carnosus by using degenerate oligonucleotides and PCR. We found that the deduced amino acid sequence was 80% identical to that of the corresponding enzyme in Staphylococcus aureus and that the ilvE gene was constitutively expressed as a monocistronic transcript. To study the influence of ilvE on BCAA catabolism, we constructed an ilvE deletion mutant by gene replacement. The IlvE protein from S. carnosus was shown mainly to catalyze the transamination of isoleucine, valine, leucine, and, to some extent, methionine using pyridoxal 5'-phosphate as a coenzyme. The ilvE mutant degraded less than 5% of the BCAAs, while the wild-type strain degraded 75 to 95%. Furthermore, the mutant strain produced approximately 100-fold less of the methyl-branched carboxy acids, 2-methylpropanoic acid, 2-methylbutanoic acid, and 3-methylbutanoic acid, which derived from the BCAA catabolism, clearly emphasizing the role of IlvE in aroma formation. In contrast to previous reports, we found that IlvE was the only enzyme that catalyzed the deamination of BCAAs in S. carnosus. The ilvE mutant strain showed remarkably lower growth rate and biomass yield compared to those of the wild-type strain when grown in rich medium. Normal growth rate and biomass yield were restored by addition of the three BCAA-derived alpha-keto acids, showing that degradation products of BCAAs were essential for optimal cell growth.
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Affiliation(s)
- Søren M Madsen
- Department of Lactic Acid Bacteria, Biotechnological Institute, Kogle Allé 2, DK-2970 Hørsholm, Denmark.
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36
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Beck HC, Hansen AM, Lauritsen FR. Metabolite production and kinetics of branched-chain aldehyde oxidation in Staphylococcus xylosus. Enzyme Microb Technol 2002. [DOI: 10.1016/s0141-0229(02)00067-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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37
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Stahnke L, Holck A, Jensen A, Nilsen A, Zanardi E. Maturity Acceleration of Italian Dried Sausage by Staphylococcus carnosus—Relationship Between Maturity and Flavor Compounds. J Food Sci 2002. [DOI: 10.1111/j.1365-2621.2002.tb08746.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Thierry A, Maillard MB, Yvon M. Conversion of L-leucine to isovaleric acid by Propionibacterium freudenreichii TL 34 and ITGP23. Appl Environ Microbiol 2002; 68:608-15. [PMID: 11823198 PMCID: PMC126662 DOI: 10.1128/aem.68.2.608-615.2002] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Several branched-chain volatile compounds are involved in the flavor of Swiss cheese. These compounds are probably produced by enzymatic conversion of branched-chain amino acids, but the flora and the pathways involved remain hypothetical. Our aim was to determine the ability of Propionibacterium freudenreichii, which is one of the main components of the secondary flora of Swiss cheese, to produce flavor compounds during leucine catabolism. Cell extracts and resting cells of two strains were incubated in the presence of L-leucine, alpha-ketoglutaric acid, and cofactors, and the metabolites produced were determined by high-performance liquid chromatography and gas chromatography. The first step of leucine catabolism was a transamination that produced alpha-ketoisocaproic acid, which was enzymatically converted to isovaleric acid. Both reactions were faster at pH 8.0 than at acidic pHs. Cell extracts catalyzed only the transamination step under our experimental conditions. Small amounts of 3-methylbutanol were also produced by resting cells, but neither 3-methylbutanal noralpha-hydroxyisocaproic acid was detected. L-Isoleucine and L-valine were also converted to the corresponding acids and alcohols. Isovaleric acid was produced by both strains during growth in a complex medium, even under conditions simulating Swiss cheese conditions (2.1% NaCl, pH 5.4, 24 degrees C). Our results show that P. frendenreichii could play a significant role in the formation of isovaleric acid during ripening.
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Affiliation(s)
- Anne Thierry
- Laboratoire de Recherches de Technologie Laitière, INRA, 65 rue de Saint-Brieuc, 35042 Rennes Cedex, France.
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39
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Sunesen L, Dorigoni V, Zanardi E, Stahnke L. Volatile compounds released during ripening in Italian dried sausage. Meat Sci 2001; 58:93-7. [DOI: 10.1016/s0309-1740(00)00139-x] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2000] [Revised: 10/18/2000] [Accepted: 10/18/2000] [Indexed: 11/26/2022]
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40
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Ability of meat starter cultures to catabolize leucine and evaluation of the degradation products by using an HPLC method. Food Microbiol 2000. [DOI: 10.1006/fmic.2000.0353] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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41
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Demeyer D, Raemaekers M, Rizzo A, Holck A, De Smedt A, ten Brink B, Hagen B, Montel C, Zanardi E, Murbrekk E, Leroy F, Vandendriessche F, Lorentsen K, Venema K, Sunesen L, Stahnke L, De Vuyst L, Talon R, Chizzolini R, Eerola S. Control of bioflavour and safety in fermented sausages: first results of a European project. Food Res Int 2000. [DOI: 10.1016/s0963-9969(00)00031-4] [Citation(s) in RCA: 111] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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