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See detailA novel sub-phylum method discriminates better the impact of crop management on soil microbial community
Degrune, Florine ULg; Dufrêne, Marc ULg; Colinet, Gilles ULg et al

in Agronomy for Sustainable Development (2015)

Soil microorganisms such as mycorrhizae and plant-growth-promoting rhizobacteria have beneficial effects on crop productivity. Agricultural practices are known to impact soil microbial communities, but ... [more ▼]

Soil microorganisms such as mycorrhizae and plant-growth-promoting rhizobacteria have beneficial effects on crop productivity. Agricultural practices are known to impact soil microbial communities, but past studies examining this impact have focused mostly on one or two taxonomic levels, such as phylum and class, thus missing potentially relevant information from lower levels. Therefore we propose here an original, sub-phylum method for studying how agricultural practices modify microbial communities. This method involves exploiting the available sequence information at the lowest taxonomic level attainable for each operational taxonomic unit. In order to validate this novel method we assessed microbial community composition using 454 pyrosequencing of 16S and 28S rRNA genes, then we compared the results with results of a phylum-level analysis. Agricultural practices included conventional tillage, reduced tillage, residue removal and residue retention. Results show that, at the lowest taxonomic level attainable, tillage is the main factor influencing both bacterial community composition, accounting for 13% of the variation, and fungal community composition, accounting for 18% of the variation. Whereas phylum-level analysis failed to reveal any effect of soil practice on bacterial community composition, and missed the fact that different members of the same phylum responded differently to tillage practice. For instance, the fungal phylum Chytridiomycota showed no impact of soil treatment, while sub-phylum-level analysis revealed an impact of tillage practice on the Chytridiomycota sub-groups Gibberella, which includes a notorious wheat pathogen, and Trichocomaceae. This clearly demonstrates the necessity of exploiting the information obtainable at sub-phylum level when assessing the effects of agricultural practice on microbial communities. [less ▲]

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See detailClostridium difficile from food and surface samples in a Belgian nursing home: An unlikely source of contamination
Rodriguez Diaz, Cristina ULg; Korsak Koulagenko, Nicolas ULg; Taminiau, Bernard ULg et al

in Anaerobe (2015), 32

This study investigates the contamination of foods and surfaces with Clostridium difficile in a single nursing home. C. difficile PCR-ribotype 078 was found in one food sample and in none of the tested ... [more ▼]

This study investigates the contamination of foods and surfaces with Clostridium difficile in a single nursing home. C. difficile PCR-ribotype 078 was found in one food sample and in none of the tested surfaces. These results indicate that food and surfaces are an unlikely source of C. difficile infection in this setting. [less ▲]

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See detailProbiotics: an update
Vandenplas, Yvan; Huys, Geert; Daube, Georges ULg

in Jornal de Pediatria (2015), 1

Objective: Triggered by the growing knowledge on the link between the intestinal microbiome and human health, the interest in probiotics is ever increasing. The authors aimed to review the recent ... [more ▼]

Objective: Triggered by the growing knowledge on the link between the intestinal microbiome and human health, the interest in probiotics is ever increasing. The authors aimed to review the recent literature on probiotics, from definitions to clinical benefits, with emphasis on children. Sources: Relevant literature from searches of PubMed, CINAHL, and recent consensus statements were reviewed. Summary of the findings: While a balanced microbiome is related to health, an imbalanced microbiome or dysbiosis is related to many health problems both within the gastro-intestinal tract, such as diarrhea and inflammatory bowel disease, and outside the gastro-intestinal tract such as obesity and allergy. In this context, a strict regulation of probiotics with health claims is urgent, because the vast majority of these products are commercialized as food (supplements), claiming health benefits that are often not substantiated with clinically relevant evidence. The major indications of probiotics are in the area of the prevention and treatment of gastrointestinal related disorders, but more data has become available on extra-intestinal indications. At least two published randomized controlled trials with the commercialized probiotic product in the claimed indication are a minimal condition before a claim can be sustained. Today, Lactobacillus rhamnosus GG and Saccharomyces boulardii are the best-studied strains. Although adverse effects have sporadically been reported, these probiotics can be considered as safe. Conclusions: Although regulation is improving, more stringent definitions are still required. Evidence of clinical benefit is accumulating, although still missing in many areas. Misuse and use of products that have not been validated constitute potential drawbacks. [less ▲]

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See detailMetagenomic analysis of the bacterial microbiota linked to the traditional Algerian date product "Btana"
Abekhti, Abdelkader; Taminiau, Bernard ULg; Kihal, Mabrouk et al

in Annals of Microbiology (2015)

In this study, using high throughput pyrosequencing, we highlighted the bacterial diversity of the traditional Algerian date product "Btana" that is produced in southern Algeria using both direct (DBM ... [more ▼]

In this study, using high throughput pyrosequencing, we highlighted the bacterial diversity of the traditional Algerian date product "Btana" that is produced in southern Algeria using both direct (DBM) and indirect (UBM) methods. Metagenomic analysis yielded a total of 103,379 reads, with a 606 total operational taxonomic units (OTUs) detected. Firmicutes represented 84.79 % of the total pyrosequencing reads. Phylogenetic analysis revealed that the Bacillales represented 90.20 % ± 15.12 % of the total reads. Among the phylotypes detected, Bacillus was the dominant genus (39.53 %). While Bacillus megaterium was shared among all of the samples, its distribution varied widely. Non-metric multidimensional scaling (nMDS) analysis showed that UBM samples clustered together, and three main OTUs were found in these UBM samples: Paenibacillus polymyxa, Paenibacillus xylanexedens, and Planomicrobium JN082684. Correlation analysis showed no association between parametersof the samples (age, pH, water activity) and the specific microbiota. [less ▲]

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See detailThermophilic and cellulolytic consortium isolated from composting plants improves anaerobic digestion of cellulosic biomass: toward a microbial resource management approach
Kinet, Romain ULg; Destain, Jacqueline ULg; Hiligsmann, Serge ULg et al

in Bioresource Technology (2015)

A cellulolytic consortium was isolated from a composting plant in order to boost the initial hydrolysis step encountered in anaerobic digestion. Improvement of the cellulose degradation, as well as biogas ... [more ▼]

A cellulolytic consortium was isolated from a composting plant in order to boost the initial hydrolysis step encountered in anaerobic digestion. Improvement of the cellulose degradation, as well as biogas production, was observed for the cultures inoculated with the exogenous consortium. Metagenomics analyses pointed out a weak richness (related to the number of OTUs) of the exogenous consortium induced by the selective pressure (cellulose as sole carbon source) met during the initial isolation steps. Main microbial strains determined were strictly anaerobic and belong to the Clostridia class. During cellulose anaerobic degradation, pH drop induced a strong modification of the microbial population. Despite the fact that richness and evenness were very weak, the exogenous consortium was able to adapt and to maintain the cellulolytic degradation potential. This important result point out the fact that simplified microbial communities could be used in order to increase the robustness of mixed cultures involved in environmental biotechnology. [less ▲]

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See detailThe impact of oregano (Origanum heracleoticum) essential oil and carvacrol on virulence gene transcription by Escherichia coli O157:H7
Mith, Hasika; Clinquart, Antoine ULg; Zhiri, Abdesselam et al

in FEMS Microbiology Letters (2015), 362

The aim of the current study was to determine, via reverse transcription quantitative polymerase chain reaction (RT-qPCR) analysis, the effect of oregano essential oil (Origanum heracleoticum) and ... [more ▼]

The aim of the current study was to determine, via reverse transcription quantitative polymerase chain reaction (RT-qPCR) analysis, the effect of oregano essential oil (Origanum heracleoticum) and carvacrol, its major component, on the expression of virulence-associated genes in enterohaemorrhagic Escherichia coli (EHEC) O157:H7 ATCC strain 35150. Both oregano oil and carvacrol demonstrated their efficacy firstly, by inhibiting the transcription of the ler gene involved in up regulation of the LEE2, LEE3 and LEE4 promoters and of attaching and effacing lesions and secondly by decreasing both Shiga toxin and fliC genes expression. In addition, a decrease in luxS gene transcription involved in quorum sensing was observed. These results were dose dependent and showed a specific effect of O. heracleoticum and carvacrol in downregulating the expression of virulence genes in EHEC O157:H7. These findings suggest that oregano oil and carvacrol have the potential to mitigate the adverse health effects caused by virulence gene expression in EHEC O157: [less ▲]

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See detailDetecting microbial patterns in relation to soil agricultural practices and the plant development stage
Degrune, Florine ULg; Dufrêne, Marc ULg; Taminiau, Bernard ULg et al

Poster (2014, December 02)

Agricultural practices have a strong impact on soil bacteria and fungi. Furthermore, microbial community composition can change with the stage of plant development. We are interested in exploring these ... [more ▼]

Agricultural practices have a strong impact on soil bacteria and fungi. Furthermore, microbial community composition can change with the stage of plant development. We are interested in exploring these effects in relation to changes induced by agriculture and plant stage in soil conditions. Some bacteria are influenced only by the plant stage, which induces changes in soil humidity, pH, nitrates, and carbon. We would thus expect these bacteria to be highly sensitive to these parameters. Other bacteria are affected only by the tillage practice applied. Further study is needed to identify the soil parameters responsible for this effect. The plant stage also has a great impact on fungal community composition. [less ▲]

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See detailMultilocus sequence typing analysis and antibiotic resistance of Clostridium difficile strains isolated from retail meat and humans in Belgium
Rodriguez Diaz, Cristina ULg; Taminiau, Bernard ULg; Avesani, Véronique et al

in Food Microbiology (2014), 42

Clostridium difficile has been isolated from food animals and meat, specially ground pork and ground beef. The recovered isolates were closely related to C. difficile human strains, indicating that ... [more ▼]

Clostridium difficile has been isolated from food animals and meat, specially ground pork and ground beef. The recovered isolates were closely related to C. difficile human strains, indicating that animals and food are possible transmission routes of human C. difficile infection. The main objective of this study was to characterize C. difficile isolates from retail meat and to compare with human isolates recovered from hospital patients in Belgium. Raw meat (beef and pork) was obtained from the retail trade. C. difficile was recovered from 2.3% of the beef samples and from 4.7% of the pork samples. A total of 4 different PCR-ribotypes were identified with a large percentage of types 078 and 014. Resistance to moxifloxacin and erythromycin was detected. The multi-locus sequence typing (MLST) analysis showed that meat and human isolates cluster in the same lineage. This study reveals the presence of toxigenic C. difficile in retail meat in Belgium with predominance PCR-ribotypes 078 and 014, which are among the four most prevalent ribotypes of C. difficile isolated from humans in Europe. [less ▲]

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See detailModelling the development of potential spoilage and biopreservative microorganisms on white pudding in different conditions of temperature based on classical microbiology and 16S rDNA metagenomic
Gand, Mathieu ULg; Cauchie, Emilie ULg; Kergourlay, Gilles ULg et al

Poster (2014, September)

An important way to prevent the spoilage of food is the respect of the cold chain during the storage. While the temperature instructions are generally respected during process and distribution of food ... [more ▼]

An important way to prevent the spoilage of food is the respect of the cold chain during the storage. While the temperature instructions are generally respected during process and distribution of food products, it is not always the case with the consumers. Indeed, a few persons reach the right temperature level required for a safe storage of foodstuffs in their refrigerator. Besides, the food can sometimes spend a few hours in ambient temperature between the buying in the supermarket and the storage in cold temperature. In this study, we propose to model the growth of microorganisms on white pudding, stored in different conditions of temperature that reflect the situations described above (constant 4°C, constant 8°C, constant 12°C, 1/3 4°C – 2/3 8°C, 1/3 4°C – breach during 4h at 20°C – 2/3 4°C and 1/3 4°C – breach during 4h at 20°C – 2/3 8°C. The product was surface inoculated with potential spoilage and biopreservative strains (Raoultella terrigena, Serratia quinivorans, Carnobacterium maltaromaticum, Lactobacillus oligofermentans, Lactobacillus nenjiangensis, Lactobacillus fuchuensis, Leuconostoc mesenteroides, lactococcus lactis and Lactobacillus graminis). Analyses by classical microbiology and V1-V3 16S rDNA metagenomics were done each day until the out of date of the food matrix. The transition from 4 to 8°C and the breach at 20°C during 4h have clearly boosted the growth of the microorganisms. The metagenomic analysis was a powerful tool to follow separately each population in each condition of storage. The results of this communication show the importance of keeping the foodstuffs in 4°C or lower in the refrigerator with the goal to avoid the spoilage or the development of pathogens and the potential of metagenomics for selection of biopreservative strains. [less ▲]

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See detailCarnobacterium maltaromaticum isolated from vacuum-packed beef with long shelf life: morphological and functional characterization
Didimo Imazaki, Pedro Henrique ULg; Tahiri, Assia ULg; Ndedi Ekolo, François et al

Poster (2014, September)

This study was conducted as part of a research project on meat conservability, in particular vacuum packaged beef displaying very long shelf lives at a temperature close to the freezing point, and its ... [more ▼]

This study was conducted as part of a research project on meat conservability, in particular vacuum packaged beef displaying very long shelf lives at a temperature close to the freezing point, and its objective was to perform a morphological and functional characterization of C. maltaromaticum with potential bioprotective effect isolated from vacuum packaged long shelf life beef. The isolated C. maltaromaticum strain presented similar morphological, biochemical and enzymatic profiles as those of two reference strains (LMG 11393 and LMG 22902). Among the studied conditions, a temperature of +12 °C and an atmosphere poor in oxygen (100 % N2) were the optimal conditions for the growth of C. maltaromaticum. Nevertheless, growth on lower temperatures is also possible. After inoculation of beef samples with C. maltaromaticum and 7 days of storage under vacuum at −1 °C, no effect was observed on the total viable count and on the count of lactic acid bacteria. A reduction of Pseudomonas sp. and Brochothrix thermosphacta was observed during the first week of storage under vacuum conditions. After 7 days of subsequent storage of the same samples under modified atmosphere at +4 °C, the inoculant favored the growth of B. thermosphacta and inhibited the growth of Enterobacteriaceae under 100 % N2. No effect of the inoculant was observed when an atmosphere rich in oxygen was applied. The evaluation of the influence of different atmospheres showed that the growth of C. maltaromaticum was slower in an atmosphere containing O2 and CO2. Long-term storage under vacuum at low temperatures are therefore suitable for the growth of this bacterium. An antimicrobial effect against Enterobacteriaceae was highlighted on inoculated fresh meat stored under N2. The functional characterization of this strain will be further pursued by genotypic characterization. Special attention will be taken to study its bioprotective properties. [less ▲]

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See detailAntimicrobial and molecular analysis of Salmonella serovar Livingstone strains isolated from humans in Tunisia and Belgium
Guedda, Intissar; Taminiau, Bernard ULg; Ferjani, Asma et al

in Journal of Infection in Developing Countries [=JIDC] (2014), 8

Introduction: Salmonella Livingstone is one of the most common serotypes responsible for nosocomial outbreaks in Tunisia. In this study, 42 isolates of Salmonella Livingstone were analyzed. Most of these ... [more ▼]

Introduction: Salmonella Livingstone is one of the most common serotypes responsible for nosocomial outbreaks in Tunisia. In this study, 42 isolates of Salmonella Livingstone were analyzed. Most of these were isolated from humans (31 strains from Tunisia and 9 strains from Belgium) and 2 isolates came from food products (beef and pork). Methodology: All strains were characterized by antibiogram, multilocus sequence typing (MLST), and virulotyping. This last technique was carried out by simple PCR of five chromosomal genes (agfA, hin/H2, iroB, phoP/Q, and slyA) and two plasmid genes (spvA and spvC). Results: All Tunisian strains were resistant to amoxicillin, amoxicillin-clavulanic acid, ticarcillin, cefalotin, gentamicin, and kanamycin. They were also resistant to third-generation cephalosporin antibiotics (cefotaxim and ceftazidim). Belgian isolates were susceptible to all antibiotics tested. Further to MLST analyses, Tunisian strains belonged to the same sequence type, ST543. For Belgian isolates, eight strains had a ST543 profile, two strains had a ST638 profile, and one strain had a ST457 profile. Analyses of the virulence gene contents showed that strains isolated in different years and from different origins had the same virulence profile. These carried all five chromosomal genes and lacked plasmid-located virulence genes spvA and spvC. Conclusions: A combination of different typing methods showed that the majority of Belgian strains and all Tunisian strains were closely related; they belonged to the same sequence type (ST543) and had the same virulence profile, but different antibiotic resistance profiles depended on the country of origin. [less ▲]

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See detailMorphological and functional characterization of Carnobacterium maltaromaticum isolated from vacuum-packed beef with long shelf life
Didimo Imazaki, Pedro Henrique ULg; Tahiri, Assia ULg; Ndedi Ekolo, François et al

Poster (2014, August)

The aim of this study was to perform a morphological and functional characterization of a Carnobacterium maltaromaticum strain with a potential bioprotective effect isolated from vacuum packaged long ... [more ▼]

The aim of this study was to perform a morphological and functional characterization of a Carnobacterium maltaromaticum strain with a potential bioprotective effect isolated from vacuum packaged long shelf life beef. The morphological, biochemical and enzymatic profiles, the influence of different temperatures and atmospheres, and the microbial stability of fresh beef inoculated with the C. maltaromaticum strain were evaluated. The isolated C. maltaromaticum strain presented similar morphological, biochemical and enzymatic profiles as those of two reference strains (LMG 11393 and LMG 22902). The growth of C. maltaromaticum was slower in an atmosphere containing O2 and CO2. Vacuum packing is therefore suitable for this bacterium. An antimicrobial effect against Enterobacteriaceae was highlighted on inoculated fresh meat stored under N2. The functional characterization of this isolate will be further pursued by a genotypic characterization to better understand its potential bioprotective effect. [less ▲]

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See detailProduction and microbiological evaluation of three types of "Dèguè", a local fermented drink made from milk in Benin
Tchekessi, Célestin; Bokossa, Auréole; Agbangla, Clément et al

in International Journal of Multidisciplinary and Current Research (2014), 2

This study consists to finalize some technologies for the production of a fermented drink called dèguè. This drink is widely consumed in Benin and other countries in sub-Saharan Africa. Following three ... [more ▼]

This study consists to finalize some technologies for the production of a fermented drink called dèguè. This drink is widely consumed in Benin and other countries in sub-Saharan Africa. Following three different technologies, we had produced three (03) types of dèguè respectively with maize flour, sorghum and millet. These types have been analyzed and their microbiological characteristics were evaluated. The microbiological analysis results obtained from the experiments have shown that lactic acid bacteria, yeasts and molds were the dominant microflora of dèguè and varied respectively 7.22log10UFC/g to 7.55log10UFC/g for lactic acid bacteria and 7.78log10UFC/g to 8.44log10UFC/g for yeasts and molds. Moreover, the statistical analysis of these results showed that there was no significant difference at 5% (p <0.05) between the three types of dèguè. The values of lactic acid bacteria obtained were consistent with the standard (≥ 107/g) attached to the yoghurt. No type contained neither total coliforms nor thermotolerant coliforms. The products (dèguès) were also free of pathogenic microorganisms such as Escherichia coli, Staphylococcus aureus and Salmonella. [less ▲]

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See detailHigh throughput sequencing analysis reveals genetic variability and selection pressure in different murine norovirus genomic regions during in vitro replication
Mauroy, Axel ULg; Taminiau, Bernard ULg; Nezer, Carine et al

Poster (2014, July)

Murine norovirus (MuNoV), a single stranded positive sense RNA virus belonging to the Caliciviridae family, is considered as a representative model for human norovirus infections, one of the most ... [more ▼]

Murine norovirus (MuNoV), a single stranded positive sense RNA virus belonging to the Caliciviridae family, is considered as a representative model for human norovirus infections, one of the most important etiological cause of both epidemic and sporadic gastroenteritis cases worldwide. Four open reading frames are described into its genome: ORF1 codes the non-structural (NS) proteins, including the viral RNA dependent RNA polymerase (RdRp); ORF2 codes the single capsid protein (VP1), wherein two domains are present: a relatively conserved domain (“shell”) and a more variable domain (“protruding”); ORF3 codes a minor structural protein; and ORF4, currently only found in viruses genetically related to MuNoV codes a virulence factor. In this study, we demonstrated by high throughput sequencing that, during serial passages of MuNoV in cell culture, the substitution rates, estimated by Bayesian inferences, did not significantly differ across the five targeted genomic regions except one. These rates were similar in four genomic regions encompassing partial non-structural 1-2 protein (NS1-2)-, NS5-, NS6-, NS7 (RdRp)- and VP1-coding sequences (coding the conserved part of the protein also including the ORF4 region). In the partial minor structural protein-coding region, this substitution rate was however estimated to be at least one log higher when expressed as substitution/site/day. The precise localisation of the detected nucleotide point mutations (substitution, deletion and insertion) were reported as well as the quantitative increase or decrease of the sequences harbouring them along ten cell culture passages. The non-silent amino acid mutations were also depicted in 3D models for four out of the five studied regions. These results have important implications for different norovirus research fields, especially in terms of diagnosis, classification methodology and genetic evolution. [less ▲]

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See detailComparison and molecular characterization of animal and human Clostridium difficile strains
Rodriguez Diaz, Cristina ULg; Taminiau, Bernard ULg; Korsak Koulagenko, Nicolas ULg et al

Poster (2014, May 07)

The main objective of this study was to characterize and compare animal and human C. difficile strains with respect to the PCR-ribotype and the antibiotic resistance. Multilocus sequence typing analysis ... [more ▼]

The main objective of this study was to characterize and compare animal and human C. difficile strains with respect to the PCR-ribotype and the antibiotic resistance. Multilocus sequence typing analysis (MLST) was performed in order to study clonal relationships of the isolates. [less ▲]

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See detailStudy of the microbial flora of steak tartare by metagenomic approach
Korsak Koulagenko, Nicolas ULg; Delhalle, Laurent ULg; Nezer, Carine et al

Poster (2014, May 06)

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See detailL'analyse par séquençage à haut débit révèle la variabilité génétique et la pression de sélection dans différentes régions génomiques du norovirus murin durant sa réplication in vitro
Mauroy, Axel ULg; Taminiau, Bernard ULg; Nezer, Carine et al

Conference (2014, March)

Le norovirus murin (MuNoV), un virus à ARN de polarité positive appartenant à la famille des Caliciviridae, est considéré comme un modèle adéquat pour les infections humaines à norovirus, une des causes ... [more ▼]

Le norovirus murin (MuNoV), un virus à ARN de polarité positive appartenant à la famille des Caliciviridae, est considéré comme un modèle adéquat pour les infections humaines à norovirus, une des causes étiologiques les plus importantes dans les cas de gastroentérite épidémique ou sporadique dans le monde entier. Quatre cadres de lecture ouverts (ORF) sont décrits au sein de son génome : l’ORF1 code les protéine non structurales (NS), dont l’ARN polymérase ARN dépendante virale (RdRp) ; l’ORF2 code l’unique protéine de capside (VP1), dans laquelle sont décrites deux régions : une relativement conservée (domaine « shell ») et une autre beaucoup plus variable (domaine « protruding ») ; l’ORF3 code une protéine structurale mineure ; et l’ORF4, actuellement uniquement décrit chez les virus génétiquement apparentés au MuNoV, code un facteur de virulence. Dans cette étude, nous démontrons par séquençage à haut débit que, durant des passages successifs du MuNoV en culture cellulaire, les taux de substitution, estimés par inférences Bayésiennes, n’ont pas significativement différé au travers des cinq régions génomiques ciblées à l’exception d’une région bien précise. Ces taux étaient similaires pour quatre régions englobant des séquences partielles codant les protéines non structurales NS1-2, NS5, NS6 et NS7 (RdRp) et VP1 dans sa région conservée (incluant également l’ORF4). Dans la région codant partiellement la protéine structurale mineure, ce taux de substitution, exprimé en substitution/site/jour, a été cependant estimé être plus élevée d’au moins une unité logarithmique. La localisation précise des mutations ponctuelles détectées (substitution, délétion et insertion) est rapportée ainsi que l’augmentation ou la diminution quantitative du nombre des séquences qui les présentaient au cours de dix passages successifs en culture cellulaire. Les localisations des mutations non silencieuses ont aussi été représentées dans une modélisation tridimensionnelle de quatre des cinq régions étudiées. Ces résultats ont d’importantes implications pour différents champs de recherche sur les norovirus, spécialement en termes de diagnostic, de méthodologie de classification et d’évolution génétique. [less ▲]

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See detailClostridium difficile infection in elderly nursing home residents.
Rodriguez Diaz, Cristina ULg; Korsak Koulagenko, Nicolas ULg; Taminiau, Bernard ULg et al

in Anaerobe (2014), 30

Age-related changes in intestinal flora and host defences, the receipt of antibiotic treatment, and the presence of underlying diseases are some of the most common risk factors associated with Clostridium ... [more ▼]

Age-related changes in intestinal flora and host defences, the receipt of antibiotic treatment, and the presence of underlying diseases are some of the most common risk factors associated with Clostridium difficile infection. Therefore, retirement care facilities for elderly people have been pinpointed as frequent sources of contamination. There is only limited data regarding the presence and epidemiology of C. difficile in nursing homes, and this gap in the current literature emphasises the need to gain a better understanding of the situation in order to prevent the emergence of new outbreaks among this population group. [less ▲]

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See detailIsolation and Quantification of Lactic Acid Bacteria from Traditional Fermented Products in Benin
Tchekessi, C.K.C.; Bokossa, I.Y; Azokpota, P. et al

in International Journal of Current Microbiology and Applied Sciences (2014), 3(11), 1-8

In Africa, fermented food products are particularly used as weaning foods for young children, pregnant women and the seniors. In Benin, most of these cereals-based foods are manufactured and sold around ... [more ▼]

In Africa, fermented food products are particularly used as weaning foods for young children, pregnant women and the seniors. In Benin, most of these cereals-based foods are manufactured and sold around the streets. These are ablo, dèguè, akpan, abotin, gowé etc ... This study focused on the isolation and enumeration of bacteria and yeast from twenty six (26) samples of traditional African fermented foods. Decimal dilution method allowed us to isolate a total of 42 different strains of microorganisms among which we counted 30 lactic acid bacteria. They confirmed their biological potential by expanding in selective medium MRS. When they were then subjected to screening, the medium of MRS-broth-starch agar, and eight (08) of the isolated strains tested showed their characters of amylolytic strains. The eight strains isolated were tested and finally cultivated at temperatures and pH ranging respectively from 30°C to 60°C and 3.0 to 6.5. These eight (08) amylolytic lactic acid bacteria (ALAB) synthesized enzyme amylase both inside and outside the bacterial cell with a very interesting activity value. The temperature limit between 40 and 45°C is best for the bacteria 26.2, B16 and B18 while the optimum pH for amylase synthesis is between 4.0 and 4.5 for the same microorganisms that have given the largest values of enzyme activity. The best strains 26.2, B16 and B18 secrete more enzymes in extracellular medium than intracellular. [less ▲]

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See detailPsychrotrophic lactic acid bacteria associated with production batch recalls and sporadic cases of early spoilage in Belgium between 2010 and 2014
Pothakos, Vasileios; Taminiau, Bernard ULg; Huys, Geert et al

in International Journal of Food Microbiology (2014), 191

Between 2010 and 2014 several spoilage cases in Belgium occurring in retail foodstuffs prior to the end of shelf-life have been reported to our laboratory. Overall, seven cases involved strictly ... [more ▼]

Between 2010 and 2014 several spoilage cases in Belgium occurring in retail foodstuffs prior to the end of shelf-life have been reported to our laboratory. Overall, seven cases involved strictly psychrotrophic lactic acid bacteria (LAB) contamination in packaged and chilled-stored food products. The products derived either fromrecalls of entire production batches or as specimens of sporadic spoilage manifestations. Some of these samples were returned to the manufacturing companies by consumers who observed the alterations after purchasing the products. The products covered a wide range of foodstuffs (i.e. meat, dairy, vegetable, egg products and composite food) and denoted different spoilage defects. However, the microbiota determined by means of 16S rRNA gene high throughput sequencing analysis underpin few LAB genera (i.e. Leuconostoc, Lactobacillus, Weissella and Lactococcus), which are frequently encountered nowadays as specific spoilage organisms (SSO) albeit overlooked by mesophilic enumeration methods due to their strictly psychrotrophic character. The present study confirms the spreading of psychrotrophic LAB in Belgian food processing environments leading to unexpected spoilage, corroborating their spoilage dynamics and prevalence in all kinds of packaged and refrigerated foodstuffs in Northern Europe. [less ▲]

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