Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    Ecophysiology of novel intestinal butyrate-producing bacteria
    Bui, Thi Phuong Nam - \ 2016
    Wageningen University. Promotor(en): Willem de Vos, co-promotor(en): Caroline Plugge. - Wageningen : Wageningen University - ISBN 9789462577015 - 202
    butyrates - butyric acid bacteria - intestines - microbial interactions - faecal examination - mice - man - infants - genomics - intestinal physiology - microbial physiology - biochemical pathways - lysine - sugar - butyraten - boterzuurbacteriën - darmen - microbiële interacties - fecesonderzoek - muizen - mens - zuigelingen - genomica - darmfysiologie - microbiële fysiologie - biochemische omzettingen - lysine - suiker

    The human intestinal tract harbours a trillion on microbial cells, predominantly anaerobes. The activity and physiology of these anaerobes is strongly associated with health and disease. This association has been investigated for a long time.However, this has not been fully understood. One of the reasons is the limited availability of cultured representatives. It is estimated that there may be more than 3000 species colonised in the gut of healthy individuals, however, only a bit over 1000 species have been isolated and characterised. Among the intestinal microbes, butyrate-producing bacteria are of special interest as the butyrate produced, is crucial to maintain a healthy gut. In addition, butyrate-producing bacteria have shown a reverse correlation with several intestinal diseases. In Chapter 2 we described a novel species Anaerostipes rhamnosivorans 1y2T isolated from an infant stool. This strain belonged to genus Anaerostipes within Clostridium cluster XIVa. A. rhamnosivorans had a capability of converting rhamnose into butyrate that is unique within intestinal butyrate-producing bacteria. The genomic analysis also revealed the entire rhamnose fermentation pathway as well as the acetyl-CoA pathway for butyrate production. This bacterium is able to produce butyrate from a wide range of sugars as well as lactate plus acetate. In Chapter 3, we described the microbial interactions between A. rhamnosivorans and Bacteriodes thetaiotaomicron in dietary pectins; Blautia hydrogenotrophica in lactate and small amount of acetate; Methanobrevibacter smithii in glucose. We observed that A. rhamnosivorans was able to benefit from its partners in all cocultures for butyrate production. This is likely due to its high metabolic flexibility. While the interaction between A. rhamnosivorans and B. thetaiotaomicron appeared as syntrophy, the interaction between A. rhamnosivorans and hydrogenotrohic microbes were cross-feeding type where hydrogen was transferred between two species. The latter resulted in an increase in butyrate level. In Chapter 4 we described a novel species Intestinimonas butyriciproducens SRB521T representing a novel genus Intestinimonas from a mouse caecum within Clostridium cluster IV. This bacterium produced butyrate and acetate as end products from Wilkins-Chalgren-Anaerobe broth.

    Butyrate production is assumed to derive from carbohydrate employing acetyl-CoA pathway. No gut bacterium is known to convert proteins or amino acids to butyrate although butyrogenic pathways from amino acid degradation have been detected in the human gut using metagenomic approach. In Chapter 5 we discovered a novel butyrate synthesis pathway from the amino acid lysine and the Amadori product fructoselysine in Intestinimonas butyriciproducens AF211 that was isolated from human stool. This strain appeared to grow much better in lysine as compared to sugars although lysine and acetyl-CoA pathways were both detected in its complete genome. Moreover, the strain AF211 was able to metabolise efficiently fructoselysine into butyrate, and acetate was found to affect the fructoselysine fermentation, representing the impact of the environmental conditions where acetate is abundant in the gut. While the lysine pathway was found in the gut of many individuals, the fructoselysine pathway was present in only half of those samples. The finding that strain I. butyriciproducens AF211 is capable of the butyrogenic conversion of amino acid lysine and fructoselysine, an Amadori product formed in heated foods via the Maillard reaction, indicated a missing link that coupling protein metabolism and butyrate formation. As this Amadori product has been implicated to play a role in aging process, the use of strain AF211 as fructoselysine clearance in the gut needs further investigation. In Chapter 6 we performed genomic and physiological comparison between the I. butyriciproducens strain AF211 (human isolate) and SRB521T (mouse isolate). I. butyriciproducens was the most abundant species within the Intestinimonas genus and highly prevalent in humans based on metadata analysis on 16S amplicons. We confirmed that the butyrogenesis from lysine was a shared characteristic between the two I. butyriciproducens strains. We also observed the host specific features including tolerance to bile, cellular fatty acid composition, more efficient capability of converting sugars into butyrate, especially galactose and arabinose, in the human strain AF211. In addition, genomic rearrangements as well as variations in bacteriophages differed among strains.

    Modeling to control spores in raw milk
    Vissers, M. - \ 2007
    Wageningen University. Promotor(en): J.M.G. Lankveld, co-promotor(en): M.C. te Giffel; P. de Jong. - [S.l.] : S.n. - ISBN 9789085046738 - 143
    rauwe melk - bacteriële sporen - boterzuurbacteriën - bacillus cereus - voedselbesmetting - microbiële besmetting - melkhygiëne - zuivelhygiëne - simulatiemodellen - raw milk - bacterial spores - butyric acid bacteria - bacillus cereus - food contamination - microbial contamination - milk hygiene - dairy hygiene - simulation models
    A modeling approach was used to identify measures at the farm that reduce transmission of microorganisms to raw milk. Butyric acid bacteria (BAB) and Bacillus cereus were used as case-studies. Minimizing the concentration of BAB spores in raw milk is important to prevent late-blowing of Gouda-type cheeses. Reducing the concentration of B. cereus spores in raw milk increases the shelf life of refrigerated pasteurized dairy products.

    First, predictive models were developed based on a translation of contamination pathways into chains of unit-operations. Via simulations, strategies were identified to control spore concentrations in farm tank milk (FTM)below 1,000 spores/L.Subsequently, the identified strategies were validated using data from a year-long field survey held at 24 Dutch farms.

    The results of this study show that mathematical modeling is very useful to identify effective measures to reduce the contamination of FTM with spores. The control strategies derived using model simulations were in agreement with results from the field survey. The following general conclusions were drawn:

    ·       To minimize the concentration of BAB spores in FTM, it is by far most important to prevent growth of BAB in grass- and corn-silage. Farmers should aim for a concentration in grass- and corn-silage fed to cowsbelow 1,000 spores/g. To achieve this, it is essential to prevent oxygen penetration into the silage silo and to remove molded and deteriorated silage from the ration fed to the cows. Measures aimed at other parts of the contamination pathway, such as teat cleaning prior to milking, are much less effective.

    ·       The concentration of B. cereus spores in FTM isnormally below 1,000 spores/L.During housing and pasturing spores of B. cereus in FTM originate from feeds. Two critical factors could lead to concentrations above 1,000 spores/L. Firstly, the contamination teats with soil is a high risk because soil can contain high concentrations of B. cereus spores. Secondly, build-up of B. cereus in improperly cleaned milking equipment could lead to high spore concentrations in FTM.

    ·       Implementation of the measures identified in this study could make late-blowing of Gouda-type cheeses a rare incident and prolong the shelf life of refrigerated pasteurized consumer milk by approximately 10%.


    A modeling approach was used to identify measures at the farm that reduce transmission of microorganisms to raw milk. Spores of butyric acid bacteria (BAB) and Bacillus cereus were used as case-studies because of their relevance for the Dutch dairy industry..The following general conclusions were drawn:

    ·       To minimize the concentration of BAB spores in FTM, it is by far most important to prevent growth of BAB in grass- and corn-silage. Farmers should aim for a concentration in grass- and corn-silage fed to cowsbelow 1,000 spores/g. To achieve this, it is essential to prevent oxygen penetration into the silage silo and to remove molded and deteriorated silage from the ration fed to the cows. Measures aimed at other parts of the contamination pathway, such as teat cleaning prior to milking, are much less effective.

    ·       The concentration of B. cereus spores in FTM isnormally below 1,000 spores/L.During housing and pasturing spores of B. cereus in FTM originate from feeds. Two critical factors could lead to concentrations above 1,000 spores/L. Firstly, the contamination teats with soil is a high risk because soil can contain high concentrations of B. cereus spores. Secondly, build-up of B. cereus in improperly cleaned milking equipment could lead to high spore concentrations in FTM.

    ·       Implementation of the measures identified in this study could make late-blowing of Gouda-type cheeses a rare incident and prolong the shelf life of refrigerated pasteurized consumer milk by approximately 10%.

    Sporen van boterzuurbacteriën; plaaggeest van kuil tot kaas
    Schooten, H.A. van; Slaghuis, B.A. ; Wemmenhove, H. ; Vissers, M. - \ 2005
    Wageningen : Animal Sciences Group - 31
    melkveehouderij - rauwe melk - melkkwaliteit - boterzuurbacteriën - hygiëne - kuilvoerbereiding - kuilvoerkwaliteit - graskuilvoer - maïskuilvoer - agrarische bedrijfsvoering - dairy farming - raw milk - milk quality - butyric acid bacteria - hygiene - silage making - silage quality - grass silage - maize silage - farm management
    In deze brochure wordt ingegaan op factoren die van invloed zijn op de besmetting van rauwe melk met sporen van boterzuurbacteriën. Daarbij is met name gekeken naar de aspecten van de voederwinning, de bewaring van het voer, de hygiëne op het bedrijf en het melken
    Zijkant kuilen kwetsbaar : rand van graskuil vaak broeinest van boterzuurbacteriën : serie boterzuur, plaaggeest van kuil tot kaas
    Schooten, H.A. van - \ 2005
    Veeteelt 22 (2005)9. - ISSN 0168-7565 - p. 58 - 59.
    grassen - graskuilvoer - kuilvoerbereiding - kuilvoerkwaliteit - boterzuurbacteriën - agrarische bedrijfsvoering - grasses - grass silage - silage making - silage quality - butyric acid bacteria - farm management
    Deel 1 van een serie van 6 over maatregelen voor het tegengaan van de boterzuurbacterie
    Boterzuur uit maïskuil : broei en schimmel vooral in aangebroken kuilen : serie boterzuur
    Schooten, H.A. van - \ 2005
    Veeteelt 22 (2005)15. - ISSN 0168-7565 - p. 20 - 21.
    boterzuurbacteriën - kuilvoerbereiding - maïskuilvoer - kuilvoerkwaliteit - agrarische bedrijfsvoering - butyric acid bacteria - silage making - maize silage - silage quality - farm management
    Het verdichten van de maïskuil, ook van de randen, en voldoende versnelheid zijn de belangrijkste maatregelen om boterzuur te voorkomen, stelt ASG-ruwvoederdeskundige Herman van Schooten in dit tweede deel uit de serie over boterzuur
    Selecteren in kuilvoer : met scherpe snede besmette plekken omzeilen : serie Boterzuur, plaaggeest van kuil tot kaas
    Hollander, C.J. - \ 2005
    Veeteelt 22 (2005)16. - ISSN 0168-7565 - p. 58 - 59.
    melkveehouderij - maïskuilvoer - kuilvoerbereiding - kuilvoerkwaliteit - boterzuurbacteriën - agrarische bedrijfsvoering - dairy farming - maize silage - silage making - silage quality - butyric acid bacteria - farm management
    Betreffende problemen met boterzuurbacteriën volgt na het inkuilen nu de bewaring, het uitkuilen en de vervoedering
    Onderzoek naar de bruikbaarheid van controlemonsters ten behoeve van de bepaling van boterzuurbacterien in boerderijmelk
    Broex, N.J.G. ; Loeffen, G.J.M. ; Smaalen, M. van; Hartog, J.M.P. den; Vermunt, A.E.M. - \ 1990
    Wageningen : RIKILT (Rapport / RIKILT 90.11) - 6
    melkkwaliteit - boterzuurbacteriën - milk quality - butyric acid bacteria
    In dit onderzoek is nagegaan of met behulp van een kuilvoersuspensie met een hoog gehalte aan boterzuurbacteriën, melkmonsters te maken zijn die gebruikt kunnen worden bij de in- en externe kwaliteitscontrole.
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