Results 161 to 170 of about 1,138 (192)

Synthesis of galactooligosaccharides and transgalactosylation modeling in reverse micelles

Enzyme and Microbial Technology, 2003
Abstract Galactooligosaccharides (GOS) were synthesized by β-galactosidase (Escherichia coli) under controllable water concentration in reverse micelles. The products were precipitated by adding acetonitrile, and then separated by a semi-preparative HPLC column. Allolactose as one of the major products was purified and verified by the 13 C
C.Will Chen, Chao-Chih Ou-Yang, Chih-Wei Yeh   +2 more
openaire   +1 more source

Transgalactosylation Catalyzed byα-Galactosidase fromCandida guilliermondiiH-404

Bioscience, Biotechnology, and Biochemistry, 1995
The thermostable alpha-galactosidase from Candida guilliermondii H-404 synthesized self-transfer products in the absence of a suitable acceptor. The main self-transfer product, using melibiose as a donor substrate, was O-alpha-D-galactosyl-(1,6)-O-alpha-D-galactosyl-(1,6)-D-glucose. This enzyme had a wide acceptor specificity.
H, Hashimoto, C, Katayama, M, Goto, T, Okinaga, S, Kitahata   +4 more
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Regiospecific synthesis of lactose analog Gal-(β 1,4)-Xyl by transgalactosylation

Canadian Journal of Chemistry, 2002
A short enzymatic synthesis of disaccharide 4-O-β-D-galactopyranosyl-D-xylose (1) has been developed, which is of interest as a lactose analog for a non-invasive medicinal determination of lactose intolerance. The starting material, benzyl α-D-xyloside, was obtained by a Fischer-type glycosidation of D-xylose with benzyl alcohol, followed by anomeric ...
Wolf-Dieter Fessner, Juan Manuel Juárez Ruiz   +1 more
openaire   +1 more source

Dendrimer-like nanoparticles based β-galactosidase assembly for enhancing its selectivity toward transgalactosylation

Enzyme and Microbial Technology, 2016
Functional nanomaterials have been pursued to assemble nanobiocatalysts since they can provide unique hierarchical nanostructures and localized nanoenvironments for enhancing enzyme specificity, stability and selectivity. Functionalized dendrimer-like hierarchically porous silica nanoparticles (HPSNs) was fabricated for assembling β-galactosidase ...
Mailin, Misson, Xin, Du, Bo, Jin, Hu, Zhang   +3 more
openaire   +2 more sources

Structural characterisation of galacto-oligosaccharides (VITAGOS™) sythesized by transgalactosylation of lactose

Bioactive Carbohydrates and Dietary Fibre, 2018
Abstract A galacto-oligosaccharide product (VITAGOS™) was prepared by glycoside hydrolases (β-galactosidase from Aspergillus oryzae and Kluyveromyces lactis ) using lactose as substrate. Monosaccharide composition analysis indicated that VITAGOS™ contained 40.3% (w/w, dry basis) glucose and 51.1% (w/w, dry basis) galactose.
Qingbin Guo, H. Douglas Goff, Steve W. Cui   +2 more
openaire   +1 more source

Production of transgalactosylated oligosaccharides (TOS) by galactosyltransferase activity from Penicillium simplicissimum

Bioresource Technology, 1999
Abstract Ingestion of transgalactosylated oligosaccharides (TOS) and other non-digestible oligosaccharides (NDOs) induces a significant increase in Bifidobacterium, Lactobacillus and some desirable species of Streptococcus populations in the gut of human and other animals (prebiotic effect).
Cruz, R., Cruz, V. D., Belote, J. G., Khenayfes, M. D., Dorta, C., Oliveira, L H D, Ardiles, E., Galli, A.   +7 more
openaire   +2 more sources

Inhibition, transgalactosylation and mechanism of action of sweet almond α-galactosidase

Biochimica et Biophysica Acta (BBA) - Enzymology, 1969
Abstract The presence of essential catalytic groups in sweet almond α-galactosidase (α- d -galactoside galactohydrolase, EC 3.2.1.22) has been investigated with the use of metal ions and photo-oxidation. Competitive inhibition was shown to occur with both Hg2+ and Ag+.
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Effective biocatalytic transgalactosylation in a supercritical fluid using a lipid-coated enzyme

Chemical Communications, 1998
A lipid-coated β-D-galactosidase is soluble and acts as an efficient trangalactosylation catalyst (the reverse hydrolysis reaction) in supercritical carbon dioxide (scCO2).
Toshiaki Mori, Yoshio Okahata
openaire   +1 more source

Hydrolytic and Transgalactosylic Activities of Commercial β-Galactosidase (Lactase) in Food Processing

1995
Publisher Summary This chapter focuses on hydrolytic and transgalactosylic activities of commercial β -galactosidase (lactase) in food processing. Food enzyme technology is the use of commercial sources of these biocatalytic compounds in the processing of food. The enzymes used for this purpose may be derived from plant, animal, or microbial sources,
L F, Pivarnik, A G, Senecal, A G, Rand
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Purification and characterization of a thermostable ?-galactosidase with high transgalactosylation activity from Saccharopolyspora rectivirgula

Applied Microbiology and Biotechnology, 1994
We purified an extracellular thermostable β-galactosidase of Saccharopolyspora rectivirgula strain V2-2, a thermophilic actinomycete, to homogeneity and characterized it to be a monomeric enzyme with a relative molecular mass of 145 000 and s°20,w of 7.1 s. In addition to the hydrolytic activity of 1-O-substituted β-d-galactopyranosides such as lactose
Masahiro Nakao, Masami Harada, Yukiko Kodama, Toru Nakayama, Yuji Shibano, Teruo Amachi   +5 more
openaire   +1 more source