Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
Polish version English version Language
enabled [disable] Abstract
Number of results

Results found: 6

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

Search:
in the keywords:  BETA-GALACTOSIDASE
help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1

Influence of reaction conditions on yield of enzymatic synthesis galactooligosacharides by Penicillium canescens beta-galactosidase

100%
Bednarski W., Kulikowska A.
Biotechnologia
|
2007
|
issue 2
137-148
EN
The aim of the work was to examine the ability of Penicillium canescens beta-galactosidase to synthesize galactooligosacharides in one or two-phase medium (organic solvents: water). The yield of this process depends mainly on: lactose concentration in water phase, time of reaction, kind of organic solvents and their participation in two-phase medium. The application of ultrafiltration for separation of saccharides from the reaction medium stabilized the yield of galactooligosacharides synthesis.
2

Immobilization of recombinant beta-galactosidase in reactions catalysed by transglutaminase

100%
Wolosowska S., Synowiecki J.
Biotechnologia
|
2005
|
issue 3
209-220
EN
Thermostable beta-galactosidase from Escherichia coli transformant containing the enzyme gene from Pyrococcus woesei was immobilized at pH 5.5 on silica gel by crosslinking with transglutaminase. The obtained preparations had a specific activity of 11.573 U/g of support at 70C using oNPG as a substrate. The optimum pH and temperature for immobilized beta-galactosidase activity were 5.5 and 95C. The immobilized enzyme is stable at the temperatures close to the optimal value and the residual activity for oNPG hydrolysis of the preparations incubated 1 h in 0.1 M phosphate citrate buffer (pH 5.5) at 100C was about 70% of the initial value.
3

Beta-galactosidase activity of proteins extracted from Sulfolobus shibatae

100%
Wolosowska S., Synowiecki J.
Biotechnologia
|
2003
|
issue 2
268-279
EN
The cytoplasmic -beta galactosidase/beta-glucosidase from hyperthermophilic archaeon Sulfolobus shibatae has been characterized with regard to its use in lactose hydrolysis. Cell extract was purified 16-fold to a specific activity 29.5 U/mg using ammonium sulfate precipitation, ion-exchange chromatography, and gel filtration. Isolated enzyme exhibited optimum activity at pH 5.5 and 98C and had a half-life of 7 h in acetate buffer (pH 5.5) at 90C. Cu2+, Hg2+ and Zn2+ strongly inhibited the enzyme, whereas catalytic properties of other investigated cations were barely influenced. Glucose and galactose were predominantly produced from lactose. However, at the substrate concentration of 0.15, M small amount of lactose was converted into transgalactosylation products.
4

Trials of stimulation extracellular secretion of beta-galactosidase synthesised by Kluyveromyces fragilis 28

100%
Demczuk A., Kowalewska-Piontas J., Bednarski W.
Biotechnologia
|
2004
|
issue 1
253-259
EN
To induce extracellular secretion of beta-galactosidase synthesised by Kluyveromyces fragilis 28 yeasts, we used: glycin, L-asparagine, L-leucine, dimethylformamide, dimethyl sulfoxide, cetyldimethylethylammonium bromide, penicillin G and glycolipids from Candida antarctica. The highest increase in the secretion of beta-galactosidase was obtained in the yeast culture cultivated in the medium with polypeptone when glycin was used as the secretion inductor. The extracellular activity of beta-galactosidase reached 0.416 A.U./ml, and was 10-fold higher than the beta-galactosidase activity reported in the control group.
5

Suitability and properties of beta-galactosidases from different sources

100%
Synowiecki J., Maciunska J.
Biotechnologia
|
2000
|
issue 1
117-123
EN
The article reviews the progress of investigations of b-galactosidases from microbial sources. These enzymes show great differences in optimal conditions of lactose hydrolysis and their utilisation create new possibilities to improve milk and milk by-products processing. Some beta-galactosidases from extreme thermophiles have significant activity above 100?C. Possible applications and interrelationship of both molecular structure and thermostability of these enzymes are also discussed.
6

Improvement of beta-galactosidase properties and conditions for its microbial biosynthesis

88%
Bednarski W., Kowalewska-Piontas J.
Biotechnologia
|
2000
|
issue 2
131-141
EN
We present examples of genetic modification of microorganisms capable of beta-galactosidase synthesis. The technological characteristics as termostability, high activity in a low temperature is improved. We also describe intensification of beta-galactosidase secretion to the medium.
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.