Kim K H, Hong J
Department of Chemical and Biochemical Engineering and Materials Science, University of California, Irvine, CA 92697, USA.
Bioresour Technol. 2001 Apr;77(2):139-44. doi: 10.1016/s0960-8524(00)00147-4.
The supercritical carbon dioxide (SC-CO2) pretreatment of lignocellulose for enzymatic hydrolysis of cellulose was investigated. Aspen (hardwood) and southern yellow pine (softwood) with moisture contents in the range of 0-73% (w/w) were pretreated with SC-CO2 at 3100 and 4000 psi and at 112-165 degrees C for 10-60 min. Each pretreated lignocellulose was hydrolyzed with commercial cellulase to assess its enzymatic digestibility. Untreated aspen and southern yellow pine (SYP) gave final reducing sugar yields of 14.5 +/- 2.3 and 12.8 +/- 2.7% of theoretical maximum, respectively. When no moisture was present in lignocellulose to be pretreated, the final reducing sugar yield from hydrolysis of SC-CO2-pretreated lignocellulose was similar to that of untreated aspen. When the moisture content of lignocellulose was increased, particularly in aspen, significantly increased final sugar yields were obtained from enzymatic hydrolysis of SC-CO2-pretreated lignocellulose. When the moisture content of lignocellulose was 73% (w/w) before pretreatment, the sugar yields from the enzymatic hydrolysis of aspen and southern yellow pine pretreated with SC-CO2 at 3100 psi and 165 degrees C for 30 min were 84.7 +/- 2.6 and 27.3 +/- 3.8% of theoretical maximum, respectively. The SC-CO2 pretreatments of both aspen and SYP with moisture contents of 40, 57, and 73% (w/w) showed significantly higher final sugar yields compared to the thermal pretreatments without SC-CO2.
研究了用于纤维素酶解的木质纤维素的超临界二氧化碳（SC-CO2）预处理。对含水量在0-73%（w/w）范围内的白杨（阔叶木）和南方黄松（针叶木），在3100和4000磅力/平方英寸以及112-165摄氏度下用SC-CO2预处理10-60分钟。将每种预处理后的木质纤维素用商业纤维素酶进行水解，以评估其酶解消化率。未处理的白杨和南方黄松（SYP）的最终还原糖产量分别为理论最大值的14.5±2.3%和12.8±2.7%。当待预处理的木质纤维素中不存在水分时，SC-CO2预处理的木质纤维素水解后的最终还原糖产量与未处理的白杨相似。当木质纤维素的含水量增加时，尤其是白杨，SC-CO2预处理的木质纤维素酶解后获得的最终糖产量显著增加。当预处理前木质纤维素的含水量为73%（w/w）时，在3100磅力/平方英寸和165摄氏度下用SC-CO2预处理30分钟的白杨和南方黄松酶解后的糖产量分别为理论最大值的84.7±2.6%和27.3±3.8%。与无SC-CO2的热预处理相比，含水量为40%、57%和73%（w/w）的白杨和SYP的SC-CO2预处理均显示出显著更高的最终糖产量。
