State Key Laboratory of Pulp and Paper Engineering, College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510640, China.
Biotechnol Bioeng. 2012 Oct;109(10):2484-93. doi: 10.1002/bit.24522. Epub 2012 Apr 25.
Cholinium amino acids ionic liquids ([Ch][AA] ILs), a novel type of bio-ILs that can easily be prepared from renewable biomaterials, were investigated for pretreatment of rice straw by selective extraction of lignin from this abundant lignocellulosic biomass material. Of the eight ILs examined, most were demonstrated to be excellent pretreatment solvents. Upon pretreatment using these ILs, the initial saccharification rates of rice straw residues were substantially improved as well as the extent to which polysaccharides could be digested (>90% for cellulose and >60% for xylan). Enzymatic hydrolysis of pretreated rice straw by Trichoderma reesei cellulase/xylanase furnished glucose and xylose with the yields in excess of 80% and 30%, respectively. Detailed spectroscopic characterization showed that the enhancement of polysaccharides degestibility derived mainly from delignification rather than changes in cellulose crystallinity. The yields of fermentable reducing sugars were significantly improved after individual optimization of pretreatment temperature and duration. With [Ch][Lys] as the solvent, the sugar yields of 84.0% for glucose and 42.1% for xylose were achieved after pretreatment at 90°C for 5 h. The IL [Ch][Lys] showed excellent reusability across five successive batches in pretreatment of rice straw. These bio-ILs performed as well as or better than previously investigated non-renewable ILs, and thus present a new and environmentally friendly way to pretreat lignocellulose for production of fermentable sugars and total utilization of the biomass.
胆碱氨基酸离子液体（[Ch][AA]ILs）是一种新型的生物离子液体，可从可再生生物材料中轻易制备，用于从丰富的木质纤维素生物质材料中选择性提取木质素来预处理稻秆。在所研究的 8 种 ILs 中，大多数被证明是出色的预处理溶剂。使用这些 ILs 进行预处理后，稻秆残渣的初始糖化率显著提高，并且多糖的消化程度也大大提高（纤维素>90%，木聚糖>60%）。里氏木霉纤维素酶/木聚糖酶对预处理后的稻秆进行酶解，葡萄糖和木糖的产率分别超过 80%和 30%。详细的光谱表征表明，多糖可消化性的提高主要源于脱木质素，而不是纤维素结晶度的变化。通过单独优化预处理温度和时间，可显著提高可发酵还原糖的产率。以[Ch][Lys]为溶剂，在 90°C 下预处理 5 h 后，可获得 84.0%的葡萄糖和 42.1%的木糖产率。IL [Ch][Lys]在预处理稻秆的五个连续批次中表现出极好的可重复使用性。这些生物离子液体的性能与之前研究的不可再生离子液体相当或更好，因此为木质纤维素的预处理提供了一种新的、环保的方法，可生产可发酵糖并实现生物质的综合利用。
