Effects of Xylan Side-Chain Substitutions on Xylan-Cellulose Interactions and Implications for Thermal Pretreatment of Cellulosic Biomass.
Biomacromolecules
; 18(4): 1311-1321, 2017 04 10.
Article
em En
| MEDLINE
| ID: mdl-28252951
ABSTRACT
Lignocellulosic biomass is mainly constituted by cellulose, hemicellulose, and lignin and represents an important resource for the sustainable production of biofuels and green chemistry materials. Xylans, a common hemicellulose, interact with cellulose and often exhibit various side chain substitutions including acetate, (4-O-methyl) glucuronic acid, and arabinose. Recent studies have shown that the distribution of xylan substitutions is not random, but follows patterns that are dependent on the plant taxonomic family and cell wall type. Here, we use molecular dynamics simulations to investigate the role of substitutions on xylan interactions with the hydrophilic cellulose face, using the recently discovered xylan decoration pattern of the conifer gymnosperms as a model. The results show that α-1,2-linked substitutions stabilize the binding of single xylan chains independently of the nature of the substitution and that Ca2+ ions can mediate cross-links between glucuronic acid substitutions of two neighboring xylan chains, thus stabilizing binding. At high temperature, xylans move from the hydrophilic to the hydrophobic cellulose surface and are also stabilized by Ca2+ cross-links. Our results help to explain the role of substitutions on xylan-cellulose interactions, and improve our understanding of the plant cell wall architecture and the fundamentals of biomass pretreatments.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Arabinose
/
Xilanos
/
Celulose
/
Ácido Glucurônico
/
Reagentes de Ligações Cruzadas
/
Acetatos
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Biomacromolecules
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Brasil