BioEnergy Research

, Volume 6, Issue 2, pp 564–579

Composition and Structure of Sugarcane Cell Wall Polysaccharides: Implications for Second-Generation Bioethanol Production

  • Amanda P. de Souza
  • Débora C. C. Leite
  • Sivakumar Pattathil
  • Michael G. Hahn
  • Marcos S. Buckeridge
Article

DOI: 10.1007/s12155-012-9268-1

Cite this article as:
de Souza, A.P., Leite, D.C.C., Pattathil, S. et al. Bioenerg. Res. (2013) 6: 564. doi:10.1007/s12155-012-9268-1

Abstract

The structure and fine structure of leaf and culm cell walls of sugarcane plants were analyzed using a combination of microscopic, chemical, biochemical, and immunological approaches. Fluorescence microscopy revealed that leaves and culm display autofluorescence and lignin distributed differently through different cell types, the former resulting from phenylpropanoids associated with vascular bundles and the latter distributed throughout all cell walls in the tissue sections. Polysaccharides in leaf and culm walls are quite similar, but differ in the proportions of xyloglucan and arabinoxylan in some fractions. In both cases, xyloglucan (XG) and arabinoxylan (AX) are closely associated with cellulose, whereas pectins, mixed-linkage-β-glucan (BG), and less branched xylans are strongly bound to cellulose. Accessibility to hydrolases of cell wall fraction increased after fractionation, suggesting that acetyl and phenolic linkages, as well as polysaccharide–polysaccharide interactions, prevented enzyme action when cell walls are assembled in its native architecture. Differently from other hemicelluloses, BG was shown to be readily accessible to lichenase when in intact walls. These results indicate that wall architecture has important implications for the development of more efficient industrial processes for second-generation bioethanol production. Considering that pretreatments such as steam explosion and alkali may lead to loss of more soluble fractions of the cell walls (BG and pectins), second-generation bioethanol, as currently proposed for sugarcane feedstock, might lead to loss of a substantial proportion of the cell wall polysaccharides, therefore decreasing the potential of sugarcane for bioethanol production in the future.

Keywords

BioenergyCellulosic ethanolHemicellulosesCell wall compositionCell wall structureSugarcane

Supplementary material

12155_2012_9268_MOESM1_ESM.xlsx (36 kb)
ESM 1(XLSX 36.4 kb)

Copyright information

© Springer Science+Business Media New York 2012

Authors and Affiliations

  • Amanda P. de Souza
    • 1
  • Débora C. C. Leite
    • 1
  • Sivakumar Pattathil
    • 2
  • Michael G. Hahn
    • 2
  • Marcos S. Buckeridge
    • 1
  1. 1.Laboratory of Plant Physiological Ecology (LAFIECO), Department of Botany, Institute of BiosciencesUniversity of São PauloSao PauloBrazil
  2. 2.BioEnergy Science Center, Complex Carbohydrate Research CenterThe University of GeorgiaAthensUSA