title: Enzymatic hydrolysis of ionic liquid-pretreated celluloses: contribution of CP-MAS 13C NMR and SEM.
abstract: The supramolecular structure of four model celluloses was altered prior to their enzymatic saccharification using two ionic liquid pretreatments: one with the commonly used 1-ethyl-3-methylimidazolium acetate ([Emim](+)[CH(3)COO](-)) and the other with the newly developed 1-ethyl-3-methylimidazolium methylphosphonate ([Emim](+)[MeO(H)PO(2)](-)). The estimation of crystallinity index (CrI) by solid state (13)C nuclear magnetic resonance for each untreated/pretreated celluloses was compared with the performances of their enzymatic hydrolysis. For α-cellulose, both pretreatments led to a significant decrease in CrI from 25% to 5% but had no effect on glucose yields. In contrast, The [Emim](+)[MeO(H)PO(2)](-) pretreatment on the long fibers of cellulose had no significant effect on the CrI although a conversion yield in glucose of 88% is obtained versus 32% without pretreatment. However, scanning electron microscopy analysis suggested a loss of fiber organization induced by both ionic liquid pretreatments leading to a larger accessibility by cellulases to the cellulose surface.
authors: Unité de Génie Enzymatique et Cellulaire, UMR 6022 CNRS-Université de Picardie Jules Verne, 33 rue Saint-Leu, Amiens Cedex, France.
authors: Eric
authors: E
authors: Husson
authors: Sébastien
authors: S
authors: Buchoux
authors: Carine
authors: C
authors: Avondo
authors: Dominique
authors: D
authors: Cailleu
authors: Karim
authors: K
authors: Djellab
authors: Isabelle
authors: I
authors: Gosselin
authors: Olivier
authors: O
authors: Wattraint
authors: Catherine
authors: C
authors: Sarazin