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A kinetic study of almond-β-glucosidase catalysed synthesis of hexyl-glycosides in low aqueous media : Influence of glycosyl donor and water activity

Andersson, Mats LU and Adlercreutz, Patrick LU (2001) In Journal of Molecular Catalysis - B Enzymatic 14(4-6). p.69-76
Abstract


A variety of alkyl and aryl glycosides were investigated as substrates for almond β-glucosidase catalysed synthesis of hexyl-β-D-glycosides in low aqueous hexanol media. The rate-limiting step in the organic media was determined to be the glycosylation of the enzyme. The kinetic constants V
max
, K
m
(glycosyl donor) and V
max
/K
m
were all influenced by the water activity and they all increased in value... (More)


A variety of alkyl and aryl glycosides were investigated as substrates for almond β-glucosidase catalysed synthesis of hexyl-β-D-glycosides in low aqueous hexanol media. The rate-limiting step in the organic media was determined to be the glycosylation of the enzyme. The kinetic constants V
max
, K
m
(glycosyl donor) and V
max
/K
m
were all influenced by the water activity and they all increased in value with increasing water activity. The increase in V
max
/K
m
was mainly determined by the increase in V
max
and a plot of log(V
max
/K
m
) versus water activity resulted in a straight line with similar slopes for all glycosides but with different absolute values and thus the most reactive substrate p-nitrophenyl glucoside was the best one in the entire water activity range studied (0.53-0.96). The preference for the two competing acceptors, hexanol and water, was not affected by the aglycon part of the glucoside. Surprisingly, the ratio between trans glycosylation and hydrolysis increased with increasing water activity. A decrease in water activity caused an increase in equilibrium yield of hexyl glycoside, as expected, but was not beneficial for the kinetically controlled yield.

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Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Almond-β-glucosidase, Kinetics, Organic solvent, Trans-glycosylation, Water activity
in
Journal of Molecular Catalysis - B Enzymatic
volume
14
issue
4-6
pages
8 pages
publisher
Elsevier
external identifiers
  • scopus:0035816504
ISSN
1381-1177
DOI
10.1016/S1381-1177(00)00238-1
language
English
LU publication?
yes
id
0c1a4dc1-af51-4a39-8259-7ce4a1ed10cc
date added to LUP
2019-06-20 15:15:51
date last changed
2020-01-13 02:03:54
@article{0c1a4dc1-af51-4a39-8259-7ce4a1ed10cc,
  abstract     = {<p><br>
                            A variety of alkyl and aryl glycosides were investigated as substrates for almond β-glucosidase catalysed synthesis of hexyl-β-D-glycosides in low aqueous hexanol media. The rate-limiting step in the organic media was determined to be the glycosylation of the enzyme. The kinetic constants V<br>
                            <sub>max</sub><br>
                            , K<br>
                            <sub>m</sub><br>
                             (glycosyl donor) and V<br>
                            <sub>max</sub><br>
                            /K<br>
                            <sub>m</sub><br>
                             were all influenced by the water activity and they all increased in value with increasing water activity. The increase in V<br>
                            <sub>max</sub><br>
                            /K<br>
                            <sub>m</sub><br>
                             was mainly determined by the increase in V<br>
                            <sub>max</sub><br>
                             and a plot of log(V<br>
                            <sub>max</sub><br>
                            /K<br>
                            <sub>m</sub><br>
                            ) versus water activity resulted in a straight line with similar slopes for all glycosides but with different absolute values and thus the most reactive substrate p-nitrophenyl glucoside was the best one in the entire water activity range studied (0.53-0.96). The preference for the two competing acceptors, hexanol and water, was not affected by the aglycon part of the glucoside. Surprisingly, the ratio between trans glycosylation and hydrolysis increased with increasing water activity. A decrease in water activity caused an increase in equilibrium yield of hexyl glycoside, as expected, but was not beneficial for the kinetically controlled yield.</p>},
  author       = {Andersson, Mats and Adlercreutz, Patrick},
  issn         = {1381-1177},
  language     = {eng},
  month        = {07},
  number       = {4-6},
  pages        = {69--76},
  publisher    = {Elsevier},
  series       = {Journal of Molecular Catalysis - B Enzymatic},
  title        = {A kinetic study of almond-β-glucosidase catalysed synthesis of hexyl-glycosides in low aqueous media : Influence of glycosyl donor and water activity},
  url          = {http://dx.doi.org/10.1016/S1381-1177(00)00238-1},
  doi          = {10.1016/S1381-1177(00)00238-1},
  volume       = {14},
  year         = {2001},
}