Fermentation of dried distillers' grains and solubles (DDGS) hydrolysates to solvents and value-added products by solventogenic clostridia
Fermentation of dried distillers' grains and solubles (DDGS) hydrolysates to solvents and value-added products by solventogenic clostridia
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DOI：
10.1016/j.biortech.2007.09.032
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发表时间：
2008-08-01
影响因子：
11.4
通讯作者：
Blaschek, Hans P.
中科院分区：
文献类型：
--
作者：
Ezeji, Thaddeus;Blaschek, Hans P.
使用稀酸、液体热水（LHW）或铵纤维膨胀（AFEX）对木质纤维素生物质进行预处理和水解，可得到复杂的糖混合物，如己糖（葡萄糖、半乳糖、甘露糖）和戊糖（木糖、阿拉伯糖）。本文详细介绍了溶媒性梭菌（Clostridium beijerinckii BA101、C. acetobutylicum 260、C. acetobutylicum 824、Clostridium saccharobutylicum 262和C. butylicum 592）对典型混合糖流（戊糖和己糖）的利用及其对糖的偏好。在这些实验中，所有的糖在发酵过程中同时被利用，尽管糖的利用率是糖特异性的。对于所有被测试的梭菌，葡萄糖的利用率高于混合物中的其他糖。此外，生物反应器中过量可发酵糖的可用性对于溶剂生产的开始和维持都是必要的，否则发酵将成为致酸性，导致发酵过程过早终止。在对一些已知的木质纤维素水解抑制剂对梭菌生长和ABE产生的影响的研究中，阿魏酸和对香豆酸被发现是生长和ABE产生的有效抑制剂。有趣的是，糠醛和HMF对溶剂性梭菌没有抑制作用；相反，当浓度达到2.0 g/L时，它们对生长和ABE产生有刺激作用。(C) 2007 Elsevier Ltd.版权所有。
Pretreatment and hydrolysis of lignocellulosic biomass using either dilute acid, liquid hot water (LHW), or ammonium fiber expansion (AFEX) results in a complex mixture of sugars such as hexoses (glucose, galactose, mannose), and pentoses (xylose, arabinose). A detailed description of the utilization of representative mixed sugar streams (pentoses and hexoses) and their sugar preferences by the solventogenic clostridia (Clostridium beijerinckii BA101, C. acetobutylicurn 260, C. acetobutylicum 824, Clostridium saccharobutylicum 262, and C. butylicum 592) is presented. In these experiments, all the sugars were utilized concurrently throughout the fermentation, although the rate of sugar utilization was sugar specific. For all clostridia tested, the rate of glucose utilization was higher than for the other sugars in the mixture. In addition, the availability of excess fermentable sugars in the bioreactor is necessary for both the onset and the maintenance of solvent production otherwise the fermentation will become acidogenic leading to premature termination of the fermentation process. During an investigation on the effect of some of the known lignocellulosic hydrolysate inhibitors on the growth and ABE production by clostridia, ferulic and p-coumaric acids were found to be potent inhibitors of growth and ABE production. Interestingly, furfural and HMF were not inhibitory to the solventogenic clostridia; rather they had a stimulatory effect on growth and ABE production at concentrations up to 2.0 g/L. (C) 2007 Elsevier Ltd. All rights reserved.