EurekaMag.com logo
+ Site Statistics
References:
53,214,146
Abstracts:
29,074,682
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on Google+Follow on Google+
Follow on LinkedInFollow on LinkedIn

+ Translate

Effect of enzymatic hydrolysis on the morphology and fine structure of pretreated cellulosic residues


Enzyme & Microbial Technology 15(10): 821-831
Effect of enzymatic hydrolysis on the morphology and fine structure of pretreated cellulosic residues
The action of Trichoderma cellulases on the various characteristics of cellulosic fractions obtained from pretreated eucalyptus chips was investigated. A screened fraction derived from a fully bleached eucalyptus kraft pulp (FBEP-48 fraction) was shown to consist of fibers with an average fiber length and an average degree of polymerization (DP) considerably higher than that obtained for the screened fraction derived from SO-2-impregnated steam-exploded eucalyptus chips which had been posttreated with alkaline hydrogen peroxide (SEE-H-2O-2, F-150 fraction). Both fractions were shown to be readily and effectively hydrolyzed by the cellulases present in the Trichoderma Celluclast preparation (Novo Nordisk). The process of enzymatic hydrolysis of both FBEP-48 and F-150 fractions resulted in a rapid decrease in the length distribution of the fibers, while small particles rapidly accumulated in the hydrolysis mixture. These particles were subsequently degraded to equivalent amounts of soluble sugars. Glucose was the main hydrolysis product, due to high amount of beta-glucosidase activity which had been added. However, at the molecular level, it was apparent that the two cellulosic substrates were hydrolyzed in distinct ways and that the mechanism appeared to be influenced by the fine structure of the substrate. As hydrolysis resulted in a gradual decrease in both the degree of polymerization and the degree of crystallinity of the F-150 fraction, it was probable that the depolymerization of this substrate was predominantly due to exoglucanase activity. By contrast, the enzymatic hydrolysis of the FBEP-48 fraction resulted in little change in either the cellulose DP or the degree of crystallinity of the substrate. The suggested a "peeling off" type of mechanism. The susceptibility of the pretreated substrates to enzymatic hydrolysis could not be easily predicted from the differences in their cellulose DP or crystallinity.

Accession: 002355404

DOI: 10.1016/0141-0229(93)90093-h

Download PDF Full Text: Effect of enzymatic hydrolysis on the morphology and fine structure of pretreated cellulosic residues



Related references

A green and efficient technology for the degradation of cellulosic materials: structure changes and enhanced enzymatic hydrolysis of natural cellulose pretreated by synergistic interaction of mechanical activation and metal salt. Bioresource Technology 177: 176-181, 2015

Organosolv pretreatment for enzymatic hydrolysis of poplars: I. Enzyme hydrolysis of cellulosic residues. Biotechnology and Bioengineering 31(7): 643-649, 1988

Enhanced production of glucose by enzymatic hydrolysis of chemical and irradiation pretreated cellulosic materials. Nahrung 35(8): 887-889, 1991

Enzymatic hydrolysis of sodium dodecyl sulphate (SDS)-pretreated newspaper for cellulosic ethanol production by Saccharomyces cerevisiae and Pichia stipitis. Applied Biochemistry and Biotechnology 162(4): 1052-1064, 2010

An evaluation of the process of pretreatments for enzymatic hydrolysis of cellulosic residues. Agricultural Science Digest Karnal 9(4): 175-178, 1989

Lignin extraction from straw by ionic liquids and enzymatic hydrolysis of the cellulosic residues. Journal of Agricultural and Food Chemistry 58(5): 2915-2922, 2010

Effect of cellulase on the morphology and fine structure of cellulosic substrates. iI. bagasse and sawdust. Cellulose chemistry and technology: 12 (2) 241-252, 1978

Effect of cellulase on the morphology and fine structure of cellulosic substrates. 3. SEM and Xray diffraction studies. Cellulose chemistry and technology 14(6): 811-820, 1980

Effect of cellulase on the morphology and fine structure of cellulosic substrates. 1. wheat straw pulp. Cellulose chemistry and technology: 11 (6) 615-625, 1977

Production of cellulosic ethanol from cotton processing residues after pretreatment with dilute sodium hydroxide and enzymatic hydrolysis. Bioresource Technology 187: 91-96, 2016