References of "Korsak Koulagenko, Nicolas"
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See detailIdentification of virulotypes and serotypes of enteropathogenic (EPEC) and Shigatoxigenic (STEC) Escherichia coli from healthy cattle at slaughterhouses in Wallonia.
Takaki, Shino; Duprez, Jean-Noël ULg; Fakih, Ibrahim et al

Poster (2016, September)

Escherichia coli producing the attachment-effacement (AE) lesion (EPEC) and/or Shiga toxins (STEC) cause enteritis and (bloody) diarrhoea in young calves and in humans, and are also present in the ... [more ▼]

Escherichia coli producing the attachment-effacement (AE) lesion (EPEC) and/or Shiga toxins (STEC) cause enteritis and (bloody) diarrhoea in young calves and in humans, and are also present in the intestines of healthy cattle. Besides the O157:H7 serotype, which is the main serotype causing STEC outbreaks in the world EPEC and STEC can belong to dozens of O serogroups. Of them, 9 have been frequently identified worldwide: O5, O26, O103, O104, O111, O118, O121, O145 and O165. The aim of this study is to identify the virulotypes and the O serotypes of EPEC and STEC isolated from healthy cattle at slaughterhouses in Wallonia. A total of 245 faeces (216 <1year-old bulls, 25 cows and 4 heifers) were sampled between April and June 2014 in 2 slaughterhouses in Wallonia and grown overnight at 37°C in Lauryl sulfate Enterobacteriaceae selective broth. The enrichment broths were assayed with an stx1, stx2 (Shiga toxin) and eae (AE lesion) triplex PCR and positive broths were inoculated onto 4 agar media: McConkey’s, Chromagar ES, Chromagar ES with tellurite and Chromagar STEC. Up to ten colonies per plate were picked up, sub-cultured and tested by the colony hybridization assay with gene probes targeting the stx1, stx2 and eae genes. The triplex PCR was again performed on all probe-positive isolates. The PCR-positive E. coli were subsequently assayed with two pentaplex PCR targeting the specific genes coding for the ten O serogroups listed above. Of the 2563 sub-cultured isolates, 744 isolates (29%) from 62 animals (25%) tested positive with the colony hybridization assay. Of them, 687 isolates (92%) from 59 animals were positive with the triplex PCR and the results of both tests were in agreement for 617 isolates (83%). One to 29 isolates per animal were probe- and PCR-positive. The positive isolates grew on Chromagar STEC (379; 55%), on Chromagar ES with tellurite (189; 28%), on Chromagar ES (62; 9%) or on McConkey’s agar (57; 8%). The most frequent virulotypes were eae+ (EPEC: 372 isolates; 54%), eae+stx1+ (AE_STEC: 119 isolates; 17%) and stx2+ (STEC: 118 isolates; 17%). In some animals different virulotypes were identified. The serogrouping with the two pentaplex PCR is in progress. AE-STEC, EPEC and STEC are excreted by 25% of the healthy cattle at slaughterhouses in Wallonia and different virulotypes can be excreted by the same animal. Conversely the methodology followed gives no precise idea of the actual level of excretion since the hybridization and PCR were performed after enrichment in selective broth. Therefore multiple isolates belonging to the same virulotype might represent the same clone. Identification of the serogroups and comparison by Pulsed Field Gel Electrophoresis should help to clarify that point. Quantitative (q)PCR is today the best method to quantify bacterial excretion, but is more expensive. The results of the hybridization and PCR correspond to between 80 and 90%. Though the colony hybridization is still useful for large-scale surveillance it needs radioactive probes for highest sensitivity and is more time-consuming than PCR. Therefore the PCR should be the first routine choice if it can be automatized at large scale. Further steps are the confirmation of the PCR results of the 70 isolates with different hybridization and PCR results and the identification of the serogroups with the two pentaplex PCR and later with PCR for the other serogroups, to compare them with isolates from young diarrhoeic calves and from humans. [less ▲]

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See detailLaboratory identification of anaerobic bacteria isolated on Clostridium difficile selective medium
Rodriguez Diaz, Cristina ULg; Warszawski, Nathalie; Korsak Koulagenko, Nicolas ULg et al

in Acta Microbiologica et Immunologica Hungarica (2016)

Despite increasing interest in the bacterium, the methodology for Clostridium difficile recovery has not yet been standardised. Cycloserine cefoxitin fructose taurocholate (CCFT) has historically been the ... [more ▼]

Despite increasing interest in the bacterium, the methodology for Clostridium difficile recovery has not yet been standardised. Cycloserine cefoxitin fructose taurocholate (CCFT) has historically been the most used medium for C. difficile isolation from human, animal, environmental and food samples, and presumptive identification is usually based on colony morphologies. However, CCFT is not totally selective. This study describes the recovery of 24 bacteria species belonging to 10 different genera other than C. difficile, present in the environment and foods of a retirement establishment that were not inhibited in the C. difficile selective medium. These findings provide insight for further environmental and food studies as well as for isolation of C. difficile on supplemented CCFT. [less ▲]

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See detailDaily intake and bacteriological quality of meat consumed in the households of Kigali, Rwanda
Niyonzima, Eugene ULg; Ongol, Martin Patrick; Brostaux, Yves ULg et al

in Food Control (2016), 69

Meat is consumed worldwide as a source of animal proteins, but it is recognized as one of the most important vehicles for food borne infections in humans. This study was conducted to determine the daily ... [more ▼]

Meat is consumed worldwide as a source of animal proteins, but it is recognized as one of the most important vehicles for food borne infections in humans. This study was conducted to determine the daily intake; the levels of hygiene indicator bacteria, namely the total mesophilic bacteria (TMC) and Escherichia coli counts (ECC); and the prevalence of Salmonella in meat consumed within the households of Kigali (Rwanda). The survey on meat consumption was carried out in 400 households by using a questionnaire, whereas the bacteriological analyses of meat samples were performed by using conventional culture methods. The results from the survey indicated that beef was the type of meat mostly consumed in Kigali city households, and the daily meat intake significantly varied with the social category of the household. No significant difference was observed between daily meat intakes in different age classes of household members. In the samples where microorganisms were detected, the average levels of TMCs and ECCs in raw meat were found to be 5.4 and 1.6 log cfu/g, respectively, whereas in cooked meat they were significantly reduced to 3.1 and 1.1 log cfu/g, respectively. The prevalence of Salmonella was reduced from 21.4% in raw meat to 3.4% in ready-to-eat cooked meat. Salmonella was not detected in cooked meat consumed in high-income households. The results from this study highlight the need for hygiene improvements in meat shops as well as in the households of Kigali, particularly those with low and medium incomes. [less ▲]

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See detailStudy of the Potential Zoonotic Transmission of Clostridium difficile in Belgian Cattle Farms.
Rodriguez Diaz, Cristina ULg; Hakimi, Djalal-Eddine; Daube, Georges ULg et al

in Journal of Food Protection (2016), 79(supplement A),

Introduction: Zoonoses are infectious that can be transmitted between animals and humans through direct contact, close proximity or the environment. Since domestic and food animals frequently test ... [more ▼]

Introduction: Zoonoses are infectious that can be transmitted between animals and humans through direct contact, close proximity or the environment. Since domestic and food animals frequently test positive for the bacterium, it seems plausible that C. difficile could be zoonotic. A former study showed that the prevalence in veal calf aged less than 6 months was 22% while in adult cattle population, it was 6,9 %. Purpose: This study aimed to determine the prevalence and the epidemiology of C. difficile in cattle farms and the possible spread of the bacterium among animals and farmers. Methods: A total of 176 faecal samples of cattle were collected from 5 different Belgian farms (south East Belgium), from November 2015 to February 2016. A stool sample of each farmer was also requested. Detection of C. difficile was performed by classical culture on C. difficile selective medium (cycloserine cefoxitin fructose cholate). Isolates were characterised by PCR-ribotyping and Genotype Cdiff test (Hain Lifescience), which allows the detection of all toxin genes, mutations in gyrA gene and the deletion in the regulator gene tcdC. Toxic activity was confirmed by a cytotoxic assay on MRC-5 cells. Results: C. difficile was detected in 14/178 (7.9%) animal samples. Isolates were grouped into five different types, including PCR-ribotype 015 (this ribotype is one the most encountered in hospitals in Belgium). The other types were UCL46A, UCL24*, UCL24, UCL33. All of them were identified as toxigenic by cytotoxicity assay and toxin genes profile. In contrast, none of the 5 farmers studied were positive for the bacterium. Significance: Results obtained indicate that PCR-ribotypes commonly isolated from hospitalised patients are also present in cattle, indicating an animal reservoir. However, a zoonotic transmission could be not demonstrated in this preliminary study. [less ▲]

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See detailExploring the bacterial diversity of Belgian steak tartare using metagenetics and qPCR analysis
Delhalle, Laurent ULg; Korsak Koulagenko, Nicolas ULg; Taminiau, Bernard ULg et al

in Journal of Food Protection (2016), 79(2), 200-229

Steak tartare is a popular meat dish in Belgium. It is prepared with raw ground minced beef and eaten with sauce, vegetables, and spiced. Since it contains raw meat, steak tartare is highly prone to ... [more ▼]

Steak tartare is a popular meat dish in Belgium. It is prepared with raw ground minced beef and eaten with sauce, vegetables, and spiced. Since it contains raw meat, steak tartare is highly prone to bacterial spoilage. The objective of this study was to explore the bacterial flora diversity in steak tartare in Belgium according to the source and to determine which bacteria are able to grow during the shelf life. A total of 58 samples from butchers’ shops, restaurants, sandwich shops and supermarkets were collected. These samples were analyzed using 16S rDNA metagenetics, a classical microbiological technique, and quantitative real-time PCR (qPCR) targeting the Lactobacillus genus. Samples were analyzed at the beginning and at the end of their shelf life, except for those from restaurants and sandwich shops analyzed only at the purchase date. Metagenetic analysis identified up to 180 bacterial species and 90 genera in some samples. But only seven bacterial species were predominant in the samples, depending on the source: Brochothrix thermosphacta, Lactobacillus algidus, Lactococcus piscium, Leuconostoc gelidum, Photobacterium kishitani, Pseudomonas spp. and Xanthomonas oryzae. With this work, an alternative method is proposed to evaluate the total flora in food samples based on the number of reads from metagenetic analysis and the results of qPCR. The degree of underestimation of aerobic plate counts (APCs) at 30°C estimated with the classical microbiology method was demonstrated in comparison with the proposed culture independent method. Compared to culture-based methods, metagenetic analysis combined with qPCR targeting Lactobacillus provides valuable information for characterizing the bacterial flora of raw meat. [less ▲]

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See detailUse of 16S rDNA Metagenetics and classical Microbiology to Assess the bacterial superficial Contamination Patterns in Bovines Classically Slaughtered or following the Halal Ritual
Korsak Koulagenko, Nicolas ULg; Taminiau, Bernard ULg; Hupperts, Caroline et al

Poster (2015, June 17)

In Belgium and in several European countries, two cattle slaughtering protocols exist: the classical method, that encompasses a stunning step before the sticking procedure, and the halal method, combining ... [more ▼]

In Belgium and in several European countries, two cattle slaughtering protocols exist: the classical method, that encompasses a stunning step before the sticking procedure, and the halal method, combining the stunning and the sticking in one single step. The main difference lies in the fact that, in the halal protocol, a single cut with a sharp knife is practiced directly on live cattle, instead of two cutting steps with two different knives for the sticking in the classical slaughtering technique. The unique section in the halal technique results generally in the cross section of trachea and esophagus of cattle. The aim of this study was to seek if the two slaughtering techniques were similar regarding the superficial contamination of carcasses, swabbed between 2 and 4 hours after the killing step. For this purpose, classical microbiological tests (TVC and Enterobacteriaceae) and 16S rDNA metagenetic analysis were carried out from 20 cattle carcasses (swabbing of “legal” zone – 1.600 cm2 – and in the neck area – 200 cm2). The classical microbiological results revealed no significant differences between the two slaughtering practices. Statistical analysis of pyrosequencing data showed that differences in bacterial population abundance between slaughtering methods were mainly found in the “legal” swabbing zone compared to the neck area. Bacterial genera belonging to Actinobacteria (Brevibacterium, Corynebacterium) were more aundant in “Halal” samples whereas populations from the Proteobacteria (Caulobacteraceae, Comamonadaceae, Bradyrhizobiaceae) and Firmicutes (Lactobacillus) were more abundand in the “classical” group. The analysis of OTU abundance of bacteria from the digestive or respiratory tract revealed no differences beteween groups. In conclusion, the slaughtering method does not influence the superficial microbiological pattern in terms of specific microbiological markers of the digestive or respiratory tract. However, precise analysis to the genus level underlines differences between methods, the legal swabbing zone being still the best sampling zone compared to the neckline. The next step will be the identification of precise contamination origin of the differences found between slaughtering methods. [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 detailShort communication: Evaluation of the microbiota of kefir samples using metagenetic analysis targeting the 16S and 26S ribosomal DNA fragments
Korsak Koulagenko, Nicolas ULg; Taminiau, Bernard ULg; Leclercq, Mathilde et al

in Journal of Dairy Science (2015), 98

Milk kefir is produced by fermenting milk in the presence of kefir grains. This beverage has several benefits for human health. The aim of this experiment was to analyze 5 kefir grains (and their products ... [more ▼]

Milk kefir is produced by fermenting milk in the presence of kefir grains. This beverage has several benefits for human health. The aim of this experiment was to analyze 5 kefir grains (and their products) using a targeted metagenetic approach. Of the 5 kefir grains analyzed, 1 was purchased in a supermarket, 2 were provided by the Ministry of Agriculture (Namur, Belgium), and 2 were provided by individuals. The metagenetic approach targeted the V1-V3 fragment of the 16S ribosomal (r)DNA for the grains and the resulting beverages at 2 levels of grain incorporation (5 and 10%) to identify the bacterial species population. In contrast, the 26S rDNA pyrosequencing was performed only on kefir grains with the aim of assessing the yeast populations. In parallel, pH measurements were performed on the kefir obtained from the kefir grains using 2 incorporation rates. Regarding the bacterial population, 16S pyrosequencing revealed the presence of 20 main bacterial species, with a dominance of the following: Lactobacillus kefiranofaciens, Lactococcus lactis ssp. cremoris, Gluconobacter frateurii, Lactobacillus kefiri, Acetobacter orientalis, and Acetobacter lovaniensis. An important difference was noticed between the kefir samples: kefir grain purchased from a supermarket (sample E) harbored a much higher proportion of several operational taxonomic units of Lactococcus lactis and Leuconostoc mesenteroides. This sample of grain was macroscopically different from the others in terms of size, apparent cohesion of the grains, structure, and texture, probably associated with a lower level of Lactobacillus kefiranofaciens. The kefir (at an incorporation rate of 5%) produced from this sample of grain was characterized by a lower pH value (4.5) than the others. The other 4 samples of kefir (5%) had pH values above 5. Comparing the kefir grain and the kefir, an increase in the population of Gluconobacter in grain sample B was observed. This was also the case for Acetobacter orientalis in sample D. In relation to 26S pyrosequencing, our study revealed the presence of 3 main yeast species: Naumovozymaspp., Kluyveromyces marxianus, and Kazachastania khefir. For Naumovozyma, further studies are needed to assess the isolation of new species. In conclusion, this study has proved that it is possible to establish the patterns of bacterial and yeast composition of kefir and kefir grain. This was only achieved with the use of high-throughput sequencing techniques. [less ▲]

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See detailDiversity of Clostridium difficile isolates from humans and animals
Rodriguez Diaz, Cristina ULg; Taminiau, Bernard ULg; Korsak Koulagenko, Nicolas ULg et al

Scientific conference (2014, October 17)

Clostridium difficile is an important cause of infectious diarrhea in hospitals. The major risk factors for the development of nosocomial C. difficile associated disease include antibiotic therapy and ... [more ▼]

Clostridium difficile is an important cause of infectious diarrhea in hospitals. The major risk factors for the development of nosocomial C. difficile associated disease include antibiotic therapy and increasing age. In animals, as pigs, calves and horses, C. difficile also seems to be an important cause of enteric disease. 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 (MLST) and multiple-Locus Variable number tandem repeat analysis (MLVA) were performed in order to study clonal relationships of the isolates. Human C. difficile isolates were obtained from care home residents and hospitalized patients. Animal isolates were collected from stool samples and carcasses of pigs and cattle at slaughter. An identification of the strains was performed by PCR-ribotyping. Further characterization was performed by antibiotic resistance, MLST and MLVA analysis. A neighbourd-joining phylogenetic three was constructed in order to determine the correlation between human and food isolates. A great variety of PCR ribotypes was found among the animal isolates, including PCR ribotypes 078 and 014. The most prevalent PCR-ribotypes in the nursing home were PCR-ribotypes 027 and 020. A high resistance to moxifloxacin, erythromycin, gentamicin and clindamycin was detected for some of the strains. Phylogenetic analysis showed that human and animal isolates with the same PCR-ribotype cluster in the same lineage, suggesting a potential risk of interspecies transmission. [less ▲]

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See detailPredictive microbiology combined with metagenomic analysis targeted on the 16S rDNA : A new approach for food quality
Delhalle, Laurent ULg; Ellouze, Mariem; Taminiau, Bernard ULg et al

Poster (2014, September 01)

The food spoilage process is mainly caused by alteration micro-organisms and classical culture-based methods may not be relevant to understand the modifications of the microbial ecology in food products ... [more ▼]

The food spoilage process is mainly caused by alteration micro-organisms and classical culture-based methods may not be relevant to understand the modifications of the microbial ecology in food products. Metagenomic analysis targeted on 16S ribosomal DNA can elucidate microbial community structures at a muche higher resolution than was previously possible. Combined with predictive microbiological models, a new approach was investigated to take into account bacterial populations dynamics in perishable foods under different environmental conditions. White pudding samples, a typical Belgian pork meat product, were packed under food wrap (atmospheric air condition). Durability studies were conducted at 4°C, 12°C and a dynamic temperature profile according to the NF V01-003 standards (4°C (1/3 of the shelf life) - 8°C (2/3 of the shelf life)) during 15 days. The effect of organic acids was also investigated using a lactic acid (1.8% w/w) treatment. At each day of the trials, classical microbiological (total flora) and 16S rDNA metagenomic analysis were carried out on all these samples. For the metagenomic analysis, a sequencing library was generated, targeting the V1-V3 region of the 16S rDNA. The two major bacterial populations were thus identified (Psychrobacter sp and Brochotrix thermosphacta) and predictive microbiology models used to assess the growth parameters. Cardinal parameters for temperature were collected on the two main bacterial species. The model was validated using the data obtained at a dynamic temperature profile. The results of the simulations for Psychrobacter sp and Brochotrix thermosphacta show a good compliance between predicted and observed data. Compared to culture based methods on selective media and previous independent culture techniques, metagenomic analysis combined with predictive microbiology gives more valuable information, and could be considered as a technological breakthrough to control the quality or for accurately determining shelf life. [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 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 detailEpidemiological tools for effective surveillance of porcine cysticercosis in Africa
Goussanou, J.S.E; Kpodekon, M.T.; Youssao, A.K.I. et al

in Veterinary World (2014), 7(3), 125-134

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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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