Enzymatic hydrolysis of ionic liquid-pretreated celluloses: contribution of CP-MAS, 13C NMR and SEM

E. Husson (1) , S. Buchoux (1) , C. Avondo (1) , D. Cailleu (2) , K. Djellab (2) , I. Gosselin (1) , O. Wattraint (1) , C. Sarazin (1)

1 GEC - Génie Enzymatique et Cellulaire
2 UPJV - Université de Picardie Jules Verne

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.

Mots clés: Cellulose; Ionic liquid; Cellulase from Trichoderma reesei; Supramolecular structure; Crystallinity

Domaines: Chimie

E. Husson, S. Buchoux, C. Avondo, D. Cailleu, K. Djellab, et al.. Enzymatic hydrolysis of ionic liquid-pretreated celluloses: contribution of CP-MAS, 13C NMR and SEM. Bioresource Technology, 2011, 102, pp.7335-7342. ⟨10.1016/j.biortech.2011.04.097⟩. ⟨hal-00637407⟩