Topochemical characterization of sugar cane pretreated with alkaline sulfite

Author(s)

Mendes, Fernanda M. ^[1] ; Heikkila, Elina ^[2] ; Fonseca, Mariana B. ^[1] ; Milagres, Adriane M. F. ^[1] ; Ferraz, Andre ^[1] ; Fardim, Pedro ^[2]

Affiliation

^[1] Univ Sao Paulo, Escola Engn Lorena, Dept Biotecnol, BR-12602810 Lorena, SP - Brazil

^[2] Abo Akad Univ, Lab Fibre & Cellulose Technol, FI-20500 Turku - Finland

• Document type: Journal article
• Source: INDUSTRIAL CROPS AND PRODUCTS; v. 69, p. 60-67, JUL 2015.
• Web of Science Citations: 12

Abstract

Biomass pretreatments and subsequent conversion to fuels and materials involve a multitude of topochemical interactions. Detailed knowledge about changes in surface composition of biomass caused by pretreatments allows tailoring of biomass processing steps to advance hydrolysis of polysaccharides to monomers. In this work, sugar cane internodes selected from experimental hybrid plants with varied chemical composition were treated with the alkali-sulfite process (ASP). A combination of Xray photoelectron spectroscopy (XPS), time-of-flight-secondary ion mass spectrometry (ToF-SIMS) and field emission scanning electron microscopy (FE-SEM) were used to evaluate the topochemical changes occurring during the pretreatment step. The chemical treatment caused intense delignification and morphological changes on the sugar cane fiber surfaces. FE-SEM indicated that the fibers from rind regions and especially from the pith-rind interface showed collapsed cell walls with grooved appearance after partial delignification. The surface coverage of carbohydrates and lignin increased and decreased after ASP, respectively, as showed by XPS and ToF-SIMS. Inorganic components such as calcium and magnesium were washed out and partially redistributed over the fiber surfaces. Our results indicated that surface lignin was dissolved during the pretreatment while surface hemicelluloses were exposed or relocated. This information can be useful to design of different mixtures of enzymes to be used after pretreatments to hydrolyse polysaccharides to monomers. (C) 2015 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 11/08826-0 - Ultrastructural characterization and enzymatic hydrolysis of chemomechanical pretreated sugar cane and sugar cane bagasse
• Grantee: Fernanda Machado Mendes Carvalho
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 11/50535-2 - Microspectrophotometry applied to the study of lignocellulose recalcitrance
• Grantee: Andre Luis Ferraz
• Support Opportunities: Regular Research Grants
• FAPESP's process: 08/56256-5 - Topochemistry, porosity and chemical composition determining successful enzymatic sacarification of sugarcane bagasse
• Grantee: Adriane Maria Ferreira Milagres
• Support Opportunities: Program for Research on Bioenergy (BIOEN) - Thematic Grants