SUPPORTING INFORMATION
1. Chemical Composition of the MFCs
The sugar composition of the MFC from birch kraft pulp before (i) and after xylan extraction (ex) and one from pine dissolving pulp was determined by classical sugar analysis, using high-pressure liquid chromatography (HPLC) with a Dionex DX500 apparatus, equipped with a Carbopac PA10 column, with water/NaOH 150 mM gradient as eluent. Prior to the analysis, the MFC samples were freeze-dried and then dissolved/hydrolyzed in/by sulfuric acid. Fucose (Sigma Aldrich) was used as internal standard.
The composition in five sugar residues namely: glucose, xylose, mannose, arabinose and galactose and the yield of hydrolysis are presented in Table 1. The normalized sugar content is calculated in Table 2 as [Glucose normalized] = [Glucose] / (yield of hydrolysis / 100)
The yield of xylan extraction (Table 2) is determined from the initial xylan content in the sample (Xy i.) and the xylan content after the xylan extraction (Xy ex.).
Yield (%) = (Xy i. - Xy ex.)/ Xy i.´100
Table S1. Sugar composition of the various samples used in this work
MFC from birch kraft pulp / MFC from pine sulfite pulp(w/w %) / i / ex / i
Glucose % / 67.2 / 78.6 / 91.6
Xylose % / 21.3 / 8.2 / 1.4
Mannose % / 0.9 / 1.4 / 0.9
Arabinose % / 0.1 / 0.1 / 0.1
Galactose % / 0.0 / 0.1 / 0.1
Hydrolysis yield % / 89.6 / 88.7 / 94
Table S2. Normalized sugar composition of the various samples used in this work
MFC from birch kraft pulp / MFC from pine sulfite pulp(w/w %) / i / ex / i
Glucose % / 75 / 88.7 / 97.5
Xylose % / 23.7 / 9.2 / 1.5
Mannose % / 1.0 / 1.5 / 1
Arabinose % / 0.1 / 0.1 / 0.0
Galactose % / 0.2 / 0.5 / 0.1
Yield of xylan extraction % / 61
Table S3. Correspondence between the xylosyl/xylan and glucosyl/cellulose contents in the different birch pulp samples used in this study. In Readsorption A, the amount of extracted xylan was reintroduced. In Readsorption B, an excess of xylan was reintroduced.
Xylosyl/glucosyl (w/w)from sugar analysis / Xylan ratio normalized to cellulose (w/w) / Xylan in interfacial conformation normalized to cellulose deduced from NMR, including inaccessible xylan
Initial sample / 24% / 75% / 0.31 / 0.31
After DMSO/LiCl extraction / 9% / 89% / 0.1 / 0.1
Readsorption A / 21% / 79% / 0.28 / 0.28
Readsorption B / 28% / 72% / 0.39 / 0.25
Figure S1. Carbon (13C) liquid NMR of xylan extracted from birch kraft samples.
Figure S2. Models of xylan and cellulose microfibrils used in this study. 24-chain cellulose Iβ model in (A) lateral view and (B) side view. (C) Molecule of xylan with DP of 10.
Figure S3. Change in sum of glycosidic dihedral angles (φ+ψ) of a xylan molecule during 10-ns equilibration run in water. At t = 0 ns, the dihedral constraints which forced the xylan to the 21 conformation was removed. The color code for the linkages corresponds to the succession of the xylosyl residues along the xylodecaose chain, starting from the non-reducing end.
Figure S4. Changes in the sum of the glycosidic dihedral angles (φ + ψ) of adsorbed xylan on different cellulose surfaces as a function of simulation time. A: (110) surface. B: (1-10) surface. C: (100) surface. The color code for the linkages corresponds to the succession of the xylosyl residues along the xylodecaose chain, starting from the non-reducing end.
Figure S5. Changes in the planar orientation angle, γ between adsorbed xylan and cellulose as a function of simulation time. A: (110) surface. B: (1-10) surface. The color code of the residues corresponds to the succession of the xylosyl residues along the xylodecaose chain, starting from the non-reducing end.
Figure S6. Chain orientation, θ (red) and end-to-end distance, r (purple) of adsorbed xylan on the cellulose surface as a function of simulation time. A: (110) surface. B: (1-10) surface.