References of "El Mejdoub, Thami"
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See detailCharacterization of Lactobacillus strains isolated from Algerian children faeces for their probiotic properties
Bahri, F.; Lejeune, Annick ULg; Dubois-Dauphin, R. et al

in African Journal of Microbiology Research [=AJMR] (2014), 8(3), 297-303

Lactic acid bacteria termed probiotics have preventive as well as curative effects on several types of diarrhoea of different aetiologies. The main objective of this study was to screen lactobacilli ... [more ▼]

Lactic acid bacteria termed probiotics have preventive as well as curative effects on several types of diarrhoea of different aetiologies. The main objective of this study was to screen lactobacilli strains having probiotic traits, isolated from Algerian healthy children faeces on the purpose of using them further in children diarrheal illnesses. One hundred and twenty (120) lactic acid bacteria isolates were selected from faecal samples of healthy Algerian children aged between five and ten years. Gram positive rods and catalase negative bacteria (52 isolates) were screened, in vitro, for their probiotic potential properties including ability to survive in simulated gastro-intestinal conditions, adherence to Caco-2 cells and their antimicrobial activity. The results show that only five strains resisted in simulated gastric juice at pH 1.5 and pepsin. Four of them were resistant to simulated intestinal conditions at pH 8 and pancreatin and have a good adherence. In the end, three of them were retained as they display interesting probiotic profiles characterized by a strong antimicrobial effect against some intestinal pathogenic bacteria. They were identified by 16S rDNA sequencing as Lactobacillus plantarum F12, Lactobacillus brevis G6 and Lactobacillus paracasei B13. [less ▲]

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See detailCOMPOSITION FOR THE RELEASE AND PROTECTION OF INSTANT ACTIVE DRY YEASTS
DE PAUW, Paul; El Mejdoub, Thami ULg; Thonart, Philippe ULg

Patent (2009)

The present invention provides a composition for preserving the stability, the fermentative activity and for favouring the release of instant active dry yeasts. [0002] A composition of the invention can ... [more ▼]

The present invention provides a composition for preserving the stability, the fermentative activity and for favouring the release of instant active dry yeasts. [0002] A composition of the invention can be in liquid, pasta-like or powdered form. The invention concerns also the method for preparing said composition and its different applications [less ▲]

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See detailComparison Of Yarrowia Lipolytica Lipase Immobilization Yield Of Entrapment, Adsorption, And Covalent Bond Techniques
Alloue, Wam.; Destain, Jacqueline ULg; El Mejdoub, Thami ULg et al

in Applied Biochemistry and Biotechnology (2008), 150(1),

The purpose of this study was to immobilize lipase from Yarrowia lipolytica using three methods including inclusion, adsorption, and covalent bond to study enzyme leaching, storage, and catalytic ... [more ▼]

The purpose of this study was to immobilize lipase from Yarrowia lipolytica using three methods including inclusion, adsorption, and covalent bond to study enzyme leaching, storage, and catalytic properties. Sodium alginate and chitosan were the polymers selected to immobilize lipase by inclusion. The beads of each polymer were dried by freeze drying and fluidization. The results show that chitosan was more adapted to the inclusion of lipase. Even though freeze dried, bead activity was low compared to that of fluidized beads. The freeze-drying process seems to produce suitable beads for storage at 4 and 20 °C. The immobilization by adsorption was carried out on both celite and silica gel. Maximum immobilization yield of 76% was obtained with celite followed by 43% in silica gel. The enzyme adsorbed on the two supports exhibited greater stability at a certain temperature (50 °C) and in no polar solvents (Isooctane, n-heptane, and n-hexane). In addition, the lipase immobilized by covalent bond retained residual activity equitable to 70%. It was demonstrated that the enzyme immobilized by covalent bond showed greater activity (80%) after 5 months of storage. [less ▲]

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See detailProteolytic Breakdown Of Gliadin By Enterococcus Faecalis Isolated From Tunisian Fermented Dough
M'Hir, S.; Aldric, Jean-Marc ULg; El Mejdoub, Thami ULg et al

in World Journal of Microbiology & Biotechnology (2008), 24(12),

The aim of this work was to select strains with proteolytic activity on wheat gliadin, among lactic acid bacteria, previously isolated from Tunisian fermented wheat dough. Hydrolysis of gliadin, as sole ... [more ▼]

The aim of this work was to select strains with proteolytic activity on wheat gliadin, among lactic acid bacteria, previously isolated from Tunisian fermented wheat dough. Hydrolysis of gliadin, as sole nitrogen source, in an agar medium was visualized by a clear zone surrounding colonies. The increase in absorbance due to gliadin breakdown was measured spectrophotometrically using Ophthaldialdehyde (OPA) on Gliadin Glucose Broth medium. Fermented liquid dough inoculated with individual selected Enterococcus faecalis, showed a decrease of the gliadin concentration from 45 g/kg to 18 g/kg determined by sandwich ELISA test (R-7001). Only the enterococci strains show an hydrolysis of gliadin proteins. Strains showing proteolytic activity are gaining more and more importance in cereal based fermented foods and may help to reduce gliadin involved in coeliac disease. [less ▲]

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See detailImmobilisation de la lipase de Yarrowia lipolytica.
Alloue, W. A. M.; Destain, Jacqueline ULg; El Mejdoub, Thami ULg et al

Poster (2007, December)

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See detailExpression of a synthetic gene encoding a Tribolium castaneum carboxylesterase in Pichia pastoris
Delroisse, Jean-Marc; Dannau, Marie; Gilsoul, Jean-Jacques et al

in Protein Expression & Purification (2005), 42(2), 286-294

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See detailEstimation of bioreactor efficiency through structured hydrodynamic modeling case study of a Pichia pastoris fed-batch process.
Delvigne, Frank ULg; El Mejdoub, Thami ULg; Destain, Jacqueline ULg et al

in Applied Biochemistry and Biotechnology (2005), 121-124

In this article, two theories are unified to investigate the effect of hydrodynamics on a specific bioprocess: the network-of-zones (NOZ) hydrodynamic structured modeling approach (developed by several ... [more ▼]

In this article, two theories are unified to investigate the effect of hydrodynamics on a specific bioprocess: the network-of-zones (NOZ) hydrodynamic structured modeling approach (developed by several researchers but applied to only a few bioprocesses) and the effectiveness factor eta approach. Two process scales were investigated (20 and 500 L), and for each, hydrodynamics were quantified using an NOZ validated by homogeneity time measurements. Several impeller combinations inducing quite different hydrodynamics were tested at the 20-L scale. After this step, effectiveness factors were determined for each fermentation run. To achieve this, a perfectly mixed microbial kinetic model was evaluated by using simple Monod kinetics with a fed-batch mass balance. This methodology permitted determination of the effectiveness factor with more accuracy because of the relation with the perfect case deduced from the Monod kinetics. It appeared that for the small scale, eta decreased until reaching a value of approx 0.7 (30% from the ideal case) for the three impeller systems investigated. However, stirring systems that include hydrofoils seemed to maintain higher effectiveness factors during the course of the fermentation. This effect can be attributed to oxygen transfer performance or to homogenization efficiency exhibited by the hydrofoils. To distinguish the oxygen transfer from the homogenization component of the effectiveness factor, these phenomena were analyzed separately. After determining the evolution of etaO2 linked to oxygen transfer for each of the fermentation runs, the NOZ model was employed to quantify substrate gradient appearance. After this step, another effectiveness factor, etamix, related to mixing was defined. Consequently, it is possible to distinguish the relative importance of the mixing effect and oxygen transfer on a given bioprocess. The results have highlighted an important scale effect on the bioprocess that can be analyzed using the NOZ model. [less ▲]

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See detailSelection de bactéries lactiques probiotiques d'origine animale
Bouzaine, T.; El Mejdoub, Thami ULg; Hamdi, M. et al

in Microbiologie et hygiène alimentaire (2004), 16(46), 24-29

Une collection de bactéries lactiques isolées à partir de la microflore intestinale de poulets de chair a été soumise à plusieurs tests de sélection afin de retenir des souches dites probiotiques. L ... [more ▼]

Une collection de bactéries lactiques isolées à partir de la microflore intestinale de poulets de chair a été soumise à plusieurs tests de sélection afin de retenir des souches dites probiotiques. L'évaluation de leur pouvoir acidifiant a révélé que les souches appartenant aux espèces Lactobacillus rhamnosus produisent environ 0,1 9g/ml d'acide lactique. Les différentes espèces étudiées ont montré une réponse variable à des pH acide, et l'espèce L. rhamnosus présente une capacité de survie même à un pH très bas de l'ordre de 2,0. La résistance au x sels biliaire, est une propriété commune à toutes les souches testées; néanmoins, le taux de croissance dans un milieu additionné de sels biliaires varie d'une espèce à une autre. L'espèce L. rhamnosus possède aussi une activité antimicrobienne remarquable contre des germes pathogènes et non pathogènes. [less ▲]

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See detailBiocontrol Of Listeria Monocytogenes In A Model Cultured Milk (Lben) By In Situ Bacteriocin Production From Lactococcus Lactis Ssp Lactis
Benkerroum, N.; Ghouati, Y.; Ghalfi, H. et al

in International Journal of Dairy Technology (2002), 55(3),

Bacteriocin-producing (Bac+) Lactococcus lactis ssp. lactis CCMM/IAV/BK1 isolated from traditional lben was used in the preparation of lben from pasteurized milk to assess its potential inhibitory ... [more ▼]

Bacteriocin-producing (Bac+) Lactococcus lactis ssp. lactis CCMM/IAV/BK1 isolated from traditional lben was used in the preparation of lben from pasteurized milk to assess its potential inhibitory activity against Listeria monocytogenes ATCC 7644. Production of bacteriocin (arbitrary units, AU) in MRS broth fortified with yeast extract (MRSY) in a fermentor under controlled and uncontrolled pH conditions was also investigated. This Bac+ strain yielded about 35 times more bacteriocin when the pH was maintained constant at 6.5 than under varying pH conditions. To test the effect of in situ bacteriocin production against L. monocytogenes, lben was made from cow's milk artificially contaminated with approximately 107 cfu/mL and fermented with a mixed mesophilic starter culture consisting of the lactococcal Bac+ organism and Lc. lactis ssp. lactis biovar diacetylactis 66, a diacetyl-producing strain, in a ratio of 1 : 1. Numbers of L. monocytogenes were monitored during fermentation and storage of lben at refrigeration temperature (c. 7°C) for up to 6 days. Performances of the Bac+ starter were compared to those of an isogenic Bac- derivative strain obtained from the Bac+ starter by curing with ethidium bromide. The results showed that the amount of L. monocytogenes decreased to below the detectable level in a 1-mL sample within 24 h of storage at 7°C in lben fermented with the Bac+ starter culture. On the contrary, L. monocytogenes survived for 6 days of storage at 7°C in lben made with the Bac- starter. The Bac+ wild strain of the starter studied could be adequately used to produce lben or similar indigenous fermented milks of improved hygienic quality on an industrial scale. Alternatively, it could be used as an adjunct in minimally processed products or in products obtained from raw milk to add a safety factor. [less ▲]

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See detailComparative study of bile salts hydrolase activity from Lactobacilli ssp.
El Mejdoub, Thami ULg; Roblain, D.; Destain, Jacqueline ULg et al

Poster (1999, July)

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See detailEffects of lactic acid bacteria addition to the shime.
El Mejdoub, Thami ULg; Nollet, L.; Roblain, D. et al

Poster (1997, August)

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