کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1384712 | 1500604 | 2016 | 10 صفحه PDF | دانلود رایگان |
• DAP induced separation of cell walls in pith but not in rind.
• The distribution of lignin droplets size differed from treated rind and pith.
• Cellulose crystallinity was not a major factor affecting cellulose digestibility.
• The changes of components distribution in rind and pith is cell type-dependent.
The recalcitrance in grasses varies according to cell type and tissue. In this study, dilute acid pretreatment was performed on Miscanthus × giganteus internodes that include rind and pith regions which showing heterogeneous structural and chemical changes. Pretreatment on pith effectively hydrolyzed 73.33% hemicelluloses and separated cohesive cell walls from the compound middle lamella due to lignin migration. Lignin droplets with an average diameter of 49.5 ± 29.3 nm were concurrently coalesced on wall surface, that in turn exposed more microfibrils deep in walls to be enzymatically hydrolyzed reaching 82.55%. By contrast, the rind with a relatively intergrated cell structure was covered by larger lignin droplets (101.2 ± 44.1 nm) and filled with inaccessible microfibrils limiting enzymatic sacchrification (31.50%). Taken together, the cellulose digestibility of biomass was not majorly influenced by cellulose crystallinity, while it was strongly correlated with the positive effects of hemicelluloses degradation, lignin redistribution, cellulose exposure and loosening cell wall structure.
Journal: Carbohydrate Polymers - Volume 154, 10 December 2016, Pages 247–256