Padmanabhan Sasisanker, Schwyter Philippe, Liu Zhongguo, Poon Geoffrey, Bell Alexis T, Prausnitz John M
Energy Biosciences Institute, University of California, Berkeley, CA, 94720-1462, USA.
Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA, 94720-1462, USA.
3 Biotech. 2016 Jun;6(1):23. doi: 10.1007/s13205-015-0344-z. Epub 2016 Jan 11.
Pretreatment of miscanthus is essential for efficient enzymatic production of cellulosic ethanol. This study reports a possible pretreatment method for miscanthus using aqueous ethylenediamine (EDA) for 30 min at 180 °C with or without ammonia. The mass ratio of miscanthus to EDA was varied from 1:3, 1:1, and 1:0.5, keeping the mass ratio of miscanthus to liquid (EDA + Water) constant at 1:8. The ammonia-to-miscanthus ratio was 1:0.25. After pretreatment with a ratio of 1:3 miscanthus to EDA, about 75 % of the lignin was removed from the raw miscanthus with 90 % retention of cellulose and 50 % of hemicellulose in the recovered solid. Enzymatic hydrolysis of the recovered solid miscanthus gave 63 % glucose and 62 % xylose conversion after 72 h. EDA provides an effective pretreatment for miscanthus, achieving good delignification and enhanced sugar yield by enzyme hydrolysis. Results using aqueous EDA with or without ammonia are much better than those using hot water and compare favorably with those using aqueous ammonia. The delignification efficiency of EDA pretreatment is high compared to that for hot-water pretreatment and is nearly as efficient as that obtained for aqueous-ammonia pretreatment.
芒草的预处理对于纤维素乙醇的高效酶法生产至关重要。本研究报道了一种可能的芒草预处理方法，即使用乙二胺（EDA）水溶液在180℃下处理30分钟，有无氨均可。芒草与EDA的质量比在1:3、1:1和1:0.5之间变化，同时保持芒草与液体（EDA + 水）的质量比恒定为1:8。氨与芒草的比例为1:0.25。在用芒草与EDA比例为1:3进行预处理后，约75%的木质素从原始芒草中去除，回收固体中纤维素保留率为90%，半纤维素保留率为50%。回收的固体芒草经酶水解72小时后，葡萄糖转化率为63%，木糖转化率为62%。EDA为芒草提供了一种有效的预处理方法，实现了良好的脱木质素效果，并通过酶水解提高了糖产量。使用含氨或不含氨的EDA水溶液的结果比使用热水的结果要好得多，并且与使用氨水的结果相当。与热水预处理相比，EDA预处理的脱木质素效率较高，几乎与氨水预处理的效率相当。
