Sanchez Gladys, Pilcher Linda, Roslander Christian, Modig Tobias, Galbe Mats, Liden Gunnar
Department of Chemical Engineering, Lund University, P.O. Box 124, 221 00 Lund, Sweden.
Bioresour Technol. 2004 Jul;93(3):249-56. doi: 10.1016/j.biortech.2003.11.003.
Hydrolysis of the straw material Paja Brava, a sturdy grass characteristic for the high plains of Bolivia, was studied in order to find suitable conditions for hydrolysis of the hemicellulose and cellulose parts. Dried Paja Brava material was pre-steamed, impregnated with dilute sulfuric acid (0.5% or 1.0% by wt), and subsequently hydrolyzed in a reactor at temperatures between 170 and 230 degrees C for a reaction time between 3 and 10 min. The highest yield of xylose (indicating efficient hydrolysis of hemicellulose) were found at a temperature of 190 degrees C, and a reaction time of 5-10 min, whereas considerably higher temperatures (230 degrees C) were needed for hydrolysis of cellulose. Fermentability of hemicellulose hydrolyzates was tested using the xylose-fermenting yeast species Pichia stipitis, Candida shehatae and Pachysolen tannophilus. The fermentability of hydrolyzates decreased strongly for hydrolyzates produced at temperatures higher than 200 degrees C.
对玻利维亚高原特有的一种坚韧草料——帕哈布拉瓦秸秆材料进行了水解研究，以寻找半纤维素和纤维素部分水解的合适条件。将干燥的帕哈布拉瓦材料进行预蒸煮，用稀硫酸（质量分数为0.5%或1.0%）浸渍，随后在反应器中于170至230摄氏度之间的温度下水解3至10分钟。在190摄氏度的温度和5至10分钟的反应时间下，木糖产量最高（表明半纤维素水解效率高），而纤维素水解则需要相当高的温度（230摄氏度）。使用发酵木糖的酵母菌种树干毕赤酵母、嗜鞣管囊酵母和谢哈塔假丝酵母测试了半纤维素水解产物的发酵能力。对于在高于200摄氏度的温度下产生的水解产物，其发酵能力大幅下降。
