2 research outputs found

    Synthesis of methyl Alpha-D-Glucoolicosaccharides by Entrapped Dextransucrase from Leuconostoc mesenteroides B-1299

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    The synthesis of methyl alpha-D-glucooligosaccharides, using sucrose as glucosyl donor and methyl alpha-D-glucopyranoside as acceptor, was studied with dextransucrase from Leuconostoc mesenteroides NRRL B-1299. The enzyme was immobilized by entrapment in alginate. By NMR and mass spectrometry we identified three homologous series (S1-S3) of methyl alpha-D-glucooligosaccharides. Series S2 and S3 were characterized by the presence of alpha(1-2) linkages, in combination with alpha(1-6) bonds. Two parameters, sucrose to acceptor concentration ratio (S/A) and the total sugar concentration (TSC) determined the yield of methyl alpha-D-glucooligosaccharides. The maximum concentration achieved of the first acceptor product, methyl alpha-D-isomaltoside, was 65 mM using a S/A 1:4 and a TSC of 336 g l-1. When increasing temperature, a shift of selectivity towards compounds containing alpha(1-2) bonds was observed. The formation of leucrose as a side process was very significant (reaching values of 32 g l-1) at high sucrose concentrations.We are very grateful to Profs. P. Monsan and M. Remaud-Simeon (INSA, Toulouse) for providing us with dextransucrase. We thank Prof. A. Cortés (ICP, CSIC) for helpful comments. We thank Gobierno Vasco and Instituto Danone for research fellowships. This work was supported by the Spanish Education and Science Ministry (Project BIO2004-03773-C04-01).Peer reviewe

    Synthesis of methyl Alpha-D-Glucoolicosaccharides by Entrapped Dextransucrase from Leuconostoc mesenteroides B-1299

    Get PDF
    The synthesis of methyl alpha-D-glucooligosaccharides, using sucrose as glucosyl donor and methyl alpha-D-glucopyranoside as acceptor, was studied with dextransucrase from Leuconostoc mesenteroides NRRL B-1299. The enzyme was immobilized by entrapment in alginate. By NMR and mass spectrometry we identified three homologous series (S1-S3) of methyl alpha-D-glucooligosaccharides. Series S2 and S3 were characterized by the presence of alpha(1-2) linkages, in combination with alpha(1-6) bonds. Two parameters, sucrose to acceptor concentration ratio (S/A) and the total sugar concentration (TSC) determined the yield of methyl alpha-D-glucooligosaccharides. The maximum concentration achieved of the first acceptor product, methyl alpha-D-isomaltoside, was 65 mM using a S/A 1:4 and a TSC of 336 g l-1. When increasing temperature, a shift of selectivity towards compounds containing alpha(1-2) bonds was observed. The formation of leucrose as a side process was very significant (reaching values of 32 g l-1) at high sucrose concentrations.We are very grateful to Profs. P. Monsan and M. Remaud-Simeon (INSA, Toulouse) for providing us with dextransucrase. We thank Prof. A. Cortés (ICP, CSIC) for helpful comments. We thank Gobierno Vasco and Instituto Danone for research fellowships. This work was supported by the Spanish Education and Science Ministry (Project BIO2004-03773-C04-01).Peer reviewe
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