Sequential pretreatments for sugarcane bagasse (scb) by NaOH followed by organosolv under mild conditions were evaluated for cellulose recovery and dilignification. The best-optimized sequential pretreatment of scb was obtained at 10% (w/v) of raw scb loading at 1% (w/v) NaOH (50 °C, 2 h) followed by treatment with organosolv (85%, v/v phosphoric acid, 50 °C, 1 h) with chilled acetone. This sequentially pretreated scb showed cellulose recovery, 66.1% (w/w) and delignification, 83.2% (w/w). NaOH or organosolv pretreated scb showed lower cellulose recovery 47.4% (w/w) or 54.5% (w/w) with lower delignification, 61% (w/w) or 56% (w/w), respectively. Pretreated solid residue of sequentially pretreated scb was enzymatically saccharified by chimera (β-glucosidase and endoglucanase, CtGH1-L1-CtGH5-F194A) and cellobiohydrolase (CtCBH5A) cloned from Clostridium thermocellum. Enzymatic hydrolysate of best sequentially pretreated scb gave total reducing sugar (TRS) yield, 230 mg/g and glucose yield, 137 mg/g pretreated scb. Only organosolv pretreated scb gave TRS yield, 112.5 mg/g and glucose yield, 72 mg/g of pretreated scb. Thus, sequentially pretreated scb resulted in 37% higher enzymatic digestibility than only orgnaosolv pretreated scb. Higher enzymatic digestibility was supported by higher crystallinity index CrI (45%) than those obtained with only organosolv pretreated (38%) or raw scb (25%). Field Emission Scanning Electron Microscope (FESEM) and Fourier-transform infrared (FT-IR) analyses showed enhanced cellulose exposure in sequentially pretreated scb. Preliminary investigation of bioethanol production at small scale by separate hydrolysis and fermentation (SHF) of enzymatic hydrolysate from best sequentially pretreated scb by Saccharomyces cerevisiae gave maximum ethanol yield of 0.42 g/g of glucose.

评价了在温和条件下依次使用 NaOH 和有机溶剂对甘蔗渣 (scb) 进行预处理的纤维素回收率和木质化作用。scb 的最佳优化顺序预处理是在 1% (w/v) NaOH (50 °C, 2 h) 的 10% (w/v) 原料 scb 负载下获得的，然后用有机溶剂 (85%, v/ v 磷酸，50 °C，1 小时）与冷冻丙酮。这种顺序预处理的 scb 显示纤维素回收率为 66.1% (w/w) 和去木质化率为 83.2% (w/w)。NaOH 或有机溶剂预处理的 scb 显示出较低的纤维素回收率，分别为 47.4% (w/w) 或 54.5% (w/w)，脱木素分别为 61% (w/w) 或 56% (w/w)。通过嵌合体（β-葡萄糖苷酶和内切葡聚糖酶，Ct GH1-L1- Ct ）对顺序预处理的scb的预处理固体残渣进行酶促糖化GH5-F194A) 和纤维二糖水解酶 ( Ct CBH5A) 从热纤梭菌中克隆。最佳顺序预处理的 scb 的酶水解产物得到总还原糖 (TRS) 产量 230 mg/g 和葡萄糖产量 137 mg/g 预处理的 scb。只有有机溶剂预处理的 scb 得到 TRS 产率 112.5 mg/g 和葡萄糖产率 72 mg/g 的预处理 scb。因此，顺序预处理的 scb 导致酶消化率比仅用 orgnaosolv 预处理的 scb 高 37%。更高的结晶度指数CrI支持更高的酶消化率(45%) 比仅用有机溶剂预处理 (38%) 或原料 scb (25%) 获得的那些。场发射扫描电子显微镜 (FESEM) 和傅里叶变换红外 (FT-IR) 分析显示，在顺序预处理的 scb 中纤维素暴露增强。通过分离水解和发酵 (SHF) 对来自酿酒酵母的最佳顺序预处理的 scb 的酶水解产物进行小规模生物乙醇生产的初步调查，得到的最大乙醇产量为 0.42 g/g 葡萄糖。