Synthesis of .BETA.-D-fucosylglucose by .BETA.-D-glucosidase I of Bifidobacterium breve clb and assimilation by bifidobacteria.

Abstract

The p-nitrophenol-releasing activity, from p-nitrophenyl (p-NP) β-d-fucoside, of βd-glucosidase I from Bifidobacterium breve clb was enhanced by the addition of many kinds of sugars and alcohols, suggesting the occurrence of a β-d-fucosyl transferring reaction. The enhancement on glucose addition was dependent on the reaction pH, and the concentrations of p-NP β-d-fucoside and glucose, and the activity reached 430% when 100 mm glucose was added to the mixture containing 20 mm p-NP p-d- fucoside at pH 4.5. A mixture of transfer products was separated from the other constituents by activated charcoal column chromatography. Further purification of the mixture by paper and thin- layer chromatographies gave four oligosaccharides, which were identified as d-fucosylglucoses with β 1 ⟶ 2, β 1 ⟶ 3, β 1 ⟶ 4 and β 1 ⟶ 6, linkages from the absorption spectra obtained with the phenol- sulfuric acid method, and the results of acid and enzymatic hydrolyses, and methylation analyses. The mixture of oligosaccharides was w...