Pingali Sai Venkatesh, Urban Volker S, Heller William T, McGaughey Joseph, O'Neill Hugh M, Foston Marcus, Myles Dean A, Ragauskas Arthur J, Evans Barbara R
Center for Structural Molecular Biology, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
Acta Crystallogr D Biol Crystallogr. 2010 Nov;66(Pt 11):1189-93. doi: 10.1107/S0907444910020408. Epub 2010 Oct 20.
Lignocellulosic biomass, which is an abundant renewable natural resource, has the potential to play a major role in the generation of renewable biofuels through its conversion to bioethanol. Unfortunately, it is a complex biological composite material that shows significant recalcitrance, making it a cost-ineffective feedstock for bioethanol production. Small-angle neutron scattering (SANS) was employed to probe the multi-scale structure of cellulosic materials. Cellulose was extracted from milled native switchgrass and from switchgrass that had undergone a dilute acid pretreatment method in order to disrupt the lignocellulose structure. The high-Q structural feature (Q > 0.07 Å(-1)) can be assigned to cellulose fibrils based on a comparison of cellulose purified by solvent extraction of native and dilute acid pretreated switchgrass and a commercial preparation of microcrystalline cellulose. Dilute acid pretreatment results in an increase in the smallest structural size, a decrease in the interconnectivity of the fibrils and no change in the smooth domain boundaries at length scales larger than 1000 Å.
木质纤维素生物质是一种丰富的可再生自然资源，通过转化为生物乙醇，它有潜力在可再生生物燃料的生产中发挥重要作用。不幸的是，它是一种复杂的生物复合材料，具有显著的顽固性，这使得它成为生物乙醇生产中成本效益不高的原料。小角中子散射（SANS）被用于探测纤维素材料的多尺度结构。从研磨后的天然柳枝稷和经过稀酸预处理以破坏木质纤维素结构的柳枝稷中提取纤维素。基于对通过溶剂萃取天然和稀酸预处理柳枝稷纯化得到的纤维素与微晶纤维素商业制剂的比较，高Q结构特征（Q>0.07 Å(-1)）可归因于纤维素原纤维。稀酸预处理导致最小结构尺寸增加、原纤维的互连性降低，并且在大于1000 Å的长度尺度上平滑域边界没有变化。
