References of "Valepyn, Emmanuel"
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See detailWater soluble exo-polysaccharide from Syncephalastrum racemosum, a strong inducer of plant defence reactions
Valepyn, Emmanuel ULg; Cabrera, Juan-Carlos; Richel, Aurore ULg et al

in Carbohydrate Polymers (2014), 101

This study examines the production, characterization and bioactivity on plant cell cultured in vitro of exopolysaccharides (EPS) from Syncephalastrum racemosum CBS 443.59. Firstly, the influence of the ... [more ▼]

This study examines the production, characterization and bioactivity on plant cell cultured in vitro of exopolysaccharides (EPS) from Syncephalastrum racemosum CBS 443.59. Firstly, the influence of the fungus culture condition in shake flasks (pH, temperature and different carbon and nitrogen sources) on EPS and biomass production were evaluated. In order to enhance EPS production, a new protocol based on two-stage pH fermentation in a 3 L stirred fermentor was developed. Under this condition, EPS production increased by 3.55 times, compared to a constant pH process, reaching a maximal EPS concentration of 2.62 g/L. Structurally, the EPS contains a polyglucuronic acid backbone, linked essentially with mannose and fucose units and some galactose and glucose units. The bioactivity of EPS as inducer of defence reactions in plant suspension-cultured cells was also studied. Our results show, for first time, that EPS from S. racemosum CBS 443.59 induces, depending on the concentration, PAL activation and H2O2 synthesis in Arabidospsis thaliana cell suspensions. [less ▲]

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See detailOptimization of Production and Preliminary Characterization of New Exopolysaccharides from Gluconacetobacter hansenii LMG1524
Valepyn, Emmanuel ULg; Berezina, Nathalie; Paquot, Michel ULg

in Advances in Microbiology (2012), 2(4), 488-496

The influence of different carbon and nitrogen sources, of ethanol concentration, the optimal pH, temperature and me-dium composition were evaluated on extracellular polysaccharides (EPS) synthesis and ... [more ▼]

The influence of different carbon and nitrogen sources, of ethanol concentration, the optimal pH, temperature and me-dium composition were evaluated on extracellular polysaccharides (EPS) synthesis and bacterial growth of Gluconace-tobacter hansenii LMG1524, and preliminary characterization of EPS was investigated. The highest EPS yields were obtained using glycerol and ammonium sulphate as carbon and nitrogen sources, respectively. The increase of ethanol concentration in the medium did not influence the EPS synthesis but reduced the bacterial growth. The optimum tem-perature and pH for polysaccharides production were respectively 25 °C and 5; whereas for cell growth were respec-tively 30 °C and 4. The optimal culture medium composition was determined as follows : 10 g/L sucrose, 0.892 g/L (NH4)2SO4, 0.34 g/L NaNO3, 3 mL acetic acid, 1.5 g/L KH2PO4, 1.5 g/L K2HPO4 and 0.6 g/L MgSO4. The polysaccha-rides produced were of 14 and 10 polymerization degrees (DP) and constituted mainly of glucose, galactose and man-nose, in relative percent of 36.36, 33.94 and 22.42, respectively. [less ▲]

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See detailExopolysaccharides production by selected bacteria
Valepyn, Emmanuel ULg; Paquot, Michel ULg; Nys, Joël

Poster (2011, August)

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See detailLipase-catalyzed synthesis of L-cysteine glucosyl esters in organic media
Valepyn, Emmanuel ULg; Nys, Joël ULg; Richel, Aurore ULg et al

in Biocatalysis & Biotransformation (2011), 29(1), 25-30

New sugar amino acids were synthesized by enzymatic esterification of D -glucose with L -cysteine using immobilized lipase B from Candida antarctica in a mixed solvent system composed of 2-methyl-2 ... [more ▼]

New sugar amino acids were synthesized by enzymatic esterification of D -glucose with L -cysteine using immobilized lipase B from Candida antarctica in a mixed solvent system composed of 2-methyl-2-butanol and dimethyl sulfoxide. Addition of small quantities of water to the medium improved the glucose conversion yield by a factor of two. [less ▲]

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See detailStudy of the acid hydrolysis of pectin extracted from sugar beet pulp
Valepyn, Emmanuel ULg; Robert, Christelle; Paquot, Michel ULg

Poster (2008, April)

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See detailProduction and properties of Yarrowia lipolytica lipase.
Destain, Jacqueline ULg; Valepyn, Emmanuel ULg; Roblain, D. et al

Poster (1995, February)

Detailed reference viewed: 13 (3 ULg)