Bioenergy Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, US Department of Agriculture, 1815 N. University Street, Peoria, IL 61604, USA.
Bioresour Technol. 2013 Aug;142:312-9. doi: 10.1016/j.biortech.2013.05.002. Epub 2013 May 10.
A pretreatment strategy for dilute H2SO4 pretreatment of corn stover was developed for the purpose of reducing the generation of inhibitory substances during pretreatment so that a detoxification step is not required prior to fermentation while maximizing sugar yield. The optimal conditions for pretreatment of corn stover (10%, w/v) were: 0.75% H2SO4, 160°C, and 0-5 min holding time. The conditions were chosen based on maximum glucose release after enzymatic hydrolysis, minimum loss of pentose sugars and minimum formation of sugar degradation products such as furfural and hydroxymethyl furfural. The pretreated corn stover after enzymatic saccharification generated 63.2 ± 2.2 and 63.7 ± 2.3 g total sugars per L at 0 and 5 min holding time, respectively. Furfural production was 0.45 ± 0.1 and 0.87 ± 0.4 g/L, respectively. The recombinant Escherichia coli strain FBR5 efficiently fermented non-detoxified corn stover hydrolyzate if the furfural content is <0.5 g/L.
针对玉米秸秆稀 H2SO4 预处理过程中抑制物生成的问题，开发了一种预处理策略，旨在降低预处理过程中抑制物的生成，从而在发酵前无需进行解毒步骤，同时最大限度地提高糖产量。玉米秸秆（10%，w/v）预处理的最佳条件为：0.75% H2SO4、160°C 和 0-5 分钟保持时间。选择这些条件的依据是酶解后葡萄糖释放量最大、戊糖损失最小以及糠醛和羟甲基糠醛等糖降解产物生成最少。在 0 和 5 分钟保持时间下，经酶解后的预处理玉米秸秆分别产生 63.2 ± 2.2 和 63.7 ± 2.3 g/L 的总糖。糠醛的产量分别为 0.45 ± 0.1 和 0.87 ± 0.4 g/L。如果糠醛含量<0.5 g/L，重组大肠杆菌 FBR5 菌株可以有效地发酵未经解毒的玉米秸秆水解液。
