School of Life Sciences and Chemical Technology, Ngee Ann Polytechnic, 535 Clementi Road, Singapore 599489, Singapore.
Appl Biochem Biotechnol. 2010 Oct;162(4):1052-64. doi: 10.1007/s12010-009-8861-z. Epub 2009 Nov 20.
Fermentation of enzymatic hydrolysate of waste newspaper was investigated for cellulosic ethanol production in this study. Various nonionic and ionic surfactants were applied for waste newspaper pretreatment to increase the enzymatic digestibility. The surfactant-pretreated newspaper was enzymatically digested in 0.05 M sodium citrate buffer (pH 4.8) with varying solid content, filter paper unit loading (FPU/g newspaper), and ratio of filter paper unit/beta-glucosidase unit (FPU/CBU). Newspaper pretreated with the anionic surfactant sodium dodecyl sulphate (SDS) demonstrated the highest sugar yield. The addition of Tween-80 in the enzymatic hydrolysis process enhanced the enzymatic digestibility of newspaper pretreated with all of the surfactants. Enzymatic hydrolysis of SDS-pretreated newspaper with 15% solid content, 15 FPU/g newspaper, and FPU/CBU of 1:4 resulted in a newspaper hydrolysate conditioning 29.07 g/L glucose and 4.08 g/L xylose after 72 h of incubation at 50 degrees C. The fermentation of the enzymatic hydrolysate with Saccharomyces cerevisiae, Pichia stipitis, and their co-culture produced 14.29, 13.45, and 14.03 g/L of ethanol, respectively. Their corresponding ethanol yields were 0.43, 0.41, and 0.42 g/g.
本研究探讨了利用酶解废纸水解物进行纤维乙醇生产。采用各种非离子型和离子型表面活性剂对废纸进行预处理，以提高酶解性能。在 0.05 M 柠檬酸钠缓冲液（pH4.8）中，用不同的固含量、滤纸单位负荷（FPU/g 废纸）和滤纸单位/β-葡萄糖苷酶单位比（FPU/CBU）对经表面活性剂预处理的报纸进行酶解。经阴离子表面活性剂十二烷基硫酸钠（SDS）预处理的报纸表现出最高的糖产量。在酶解过程中添加 Tween-80 可提高所有表面活性剂预处理的报纸的酶解性能。在 50°C 下孵育 72 小时后，用 15%固含量、15 FPU/g 报纸和 FPU/CBU 为 1:4 的 SDS 预处理的报纸进行酶解，得到的报纸水解液中含有 29.07 g/L 的葡萄糖和 4.08 g/L 的木糖。利用酿酒酵母、毕赤酵母及其共培养物对酶解液进行发酵，分别产生了 14.29、13.45 和 14.03 g/L 的乙醇，相应的乙醇产率分别为 0.43、0.41 和 0.42 g/g。
