Linked Life Data

11374467

Source:http://linkedlifedata.com/resource/pubmed/id/11374467

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2001-5-25
pubmed:abstractText
A commercially available almond emulsin beta-glucosidase preparation has been reported to have chitobiose activity, and can hydrolyze chitin substrates due to a chitinase present in the enzyme preparation. This beta-glucosidase preparation was used to investigate hydrolytic activity on five chitosan samples with different molecular weight and degree of deacetylation. The degree of deacetylation and molecular weight of the chitosan samples were determined using a circular dichroism and a viscometric method, respectively. The hydrolytic activity of this beta-glucosidase preparation on chitosan was monitored viscometrically as the most convenient means of screening. Solutions of chitosan in pH 5.0 acetate buffer were prepared using the different viscosity grades of chitosan. The specific viscosity, measured after addition of beta-glucosidase to the above solutions, decreased dramatically over time in comparison to that of the respective control mixture without enzyme. Eadie-Hofstee plots established that hydrolysis of chitosan by this enzyme preparation obeyed Michaelis-Menten kinetics. Apparent Michaelis-Menten parameters and initial degradation rates were calculated and compared to determine the influences of the degree of deacetylation and molecular weight on the hydrolysis. The results show that higher molecular weight and higher degree of deacetylation chitosans possessed a lower affinity for the enzyme and a slower degradation rate. Faster degradation rates, then, are expected with lower molecular weight and low degree of deacetylation chitosans. Hydrolysis of these chitosan samples confirms the existence of a chitinase in the almond emulsin beta-glucosidase preparation, and further studies are warranted.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0142-9612
pubmed:author
pubmed:issnType
Print
pubmed:volume
22
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1653-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
In vitro degradation of chitosan by a commercial enzyme preparation: effect of molecular weight and degree of deacetylation.
pubmed:affiliation
Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, 64110, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't