## 4 Conclusions  
The proposed integrated hydrothermal-DES pretreatment is efficient in destroying the recalcitrance of green bamboo into three well-defined components, with hemicellulose and lignin removal of 88.6% and 79.1%, respectively. The comprehensive and value-added utilization of bamboo is achieved by the transformation of hemicellulose, cellulose, and lignin into xylo-oligosaccharides, glucose, and antioxidants. More importantly, ChCI-LA has a superior delignification performance even after five recycling runs, exhibiting the potential to reduce operating cost for industrial consideration.  
The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/app1304249/s1](https://www.mdpi.com/article/10.3390/app1304249/s1)]([https://www.mdpi.com/article/10.3390/app1304249/s1](https://www.mdpi.com/article/10.3390/app1304249/s1)), Figure S1: The records of experimental temperature to hydrothermal time under different hydrothermal conditions: (**a**) temperature, (**b**) time, and (**c**) solid-to-liquid ratio; Figure S2: Surface morphology of bamboo particles: (**a**) untreated bamboo; hydrothermal pretreatment at (**b**) 160 \({}^{\circ}\)C\(-\)30 min\(-\)3/30 g/mL, (**c**) 170 \({}^{\circ}\)C\(-\)30 min\(-\)3/30 g/mL, (**d**) 180 \({}^{\circ}\)C\(-\)30 min\(-\)3/30 g/mL, (**e**) 190 \({}^{\circ}\)C\(-\)30 min\(-\)3/30 g/mL, (**f**) 200 \({}^{\circ}\)C\(-\)30 min\(-\)3/30 g/mL, (**g**) 210 \({}^{\circ}\)C\(-\)30 min\(-\)3/30 g/mL, (**h**) 180 \({}^{\circ}\)C\(-\)20 min\(-\)3/30 g/mL, (**i**) 180 \({}^{\circ}\)C\(-\)35 min\(-\)3/30 g/mL, (**j**) 180 \({}^{\circ}\)C\(-\)40 min\(-\)3/30 g/mL, (**k**) 180 \({}^{\circ}\)C\(-\)45 min\(-\)3/30 g/mL, (**l**) 180 \({}^{\circ}\)C\(-\)50 min\(-\)3/30 g/mL, (**m**) 180 \({}^{\circ}\)C\(-\)35 min\(-\)3/36 g/mL, (**o**) 180 \({}^{\circ}\)C\(-\)35 min\(-\)3/34 g/mL, (**p**) 180 \({}^{\circ}\)C\(-\)35 min\(-\)3/48 g/mL, (**q**) 180 \({}^{\circ}\)C\(-\)35 min\(-\)3/60 g/mL; Figure S3: Effect of DEL concentration on inhibitory ratio; Figure S4: Glucose concentration and saccharification ratio during the optimization of enzymatic parameters. (**l**) 30 FPU/g\({}_{\text{glyucan}}\) of Cellic Cfec3, solid loading of 2-10% (\(w/v\)) without chemical additives; (**l**) 30 FPU/g\({}_{\text{glyucan}}\) of Cellic Cfec3, solid loading of 5% (\(w/v\)), a Tween-20 concentration of 5-25 mg/mL; (**l**) 30 FPU/g\({}_{\text{glyucan}}\) of Cellic Cfec3, solid loading of 5% (\(w/v\)), a BSA concentration of 5-25 mg/mL; (**l**) 30 FPU/g\({}_{\text{glyucan}}\) of cellulase complexes with a Cellic Cfec3 percentage of 0-100%, solid loading of 5% (\(w/v\)) without chemical additives; (**V**) 50 FPU/g\({}_{\text{glyucan}}\) of cellulase complexes with a Cellic Cfec3 percentage of 0-100%, solid loading of 5% (\(w/v\)) without chemical additives; (**V**1 70 FPU/g\({}_{\text{glyucan}}\) of cellulase complexes with a Cellic Cfec3 percentage of 0-100%, solid loading of 5% (\(w/v\)) without chemical additives; (**V**II 90 FPU/g\({}_{\text{glyucan}}\) of cellulase complexes with a Cellic Cfec3 percentage of 0-100%, solid loading of 5% (\(w/v\)) without chemical additives; Table S1: Characteristic bands of FTIR spectra of bamboo samples; Table S2: Assignments of 13C-1H correlations in the HSQC spectra of lignin from green bamboo.  
Conceptualization, L.G. and K.S.; validation, J.S., Y.X., Q.C. and S.Y.; formal analysis, L.C., J.S., R.Y. and Y.X.; investigation, L.C. and R.Y.; writing--original draft preparation, L.C.; writing--review and editing, L.G., K.S. and L.C.; visualization, L.C., Q.C. and S.Y.; supervision, L.G.; project administration, L.G. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the Guiding Project of Science and Technology Plan of Fujian Province, China, grant number 2020N0011.  
Figure 8: Comparison of enzymatic saccharification among untreated bamboo, hydrothermally treated bamboo, and cellulose residue.