Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea.
Clean Energy Research Center, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea; Clean Energy and Chemical Engineering, Korea University of Science and Technology, Daejeon 34113, Republic of Korea.
Bioresour Technol. 2016 Dec;222:422-430. doi: 10.1016/j.biortech.2016.09.130. Epub 2016 Oct 6.
The efficient fermentation of lignocellulosic hydrolysates in the presence of inhibitors is highly desirable for bioethanol production. Among the inhibitors, acetic acid released during the pretreatment of lignocellulose negatively affects the fermentation performance of biofuel producing organisms. In this study, we evaluated the inhibitory effects of acetic acid on glucose and xylose fermentation by a high performance engineered strain of xylose utilizing Saccharomyces cerevisiae, SXA-R2P-E, harboring a xylose isomerase based pathway. The presence of acetic acid severely decreased the xylose fermentation performance of this strain. However, the acetic acid stress was alleviated by metal ion supplementation resulting in a 52% increased ethanol production rate under 2g/L of acetic acid stress. This study shows the inhibitory effect of acetic acid on an engineered isomerase-based xylose utilizing strain and suggests a simple but effective method to improve the co-fermentation performance under acetic acid stress for efficient bioethanol production.
在存在抑制剂的情况下，高效发酵木质纤维素水解物对于生物乙醇生产是非常理想的。在这些抑制剂中，木质纤维素预处理过程中释放的乙酸会对生物燃料产生菌的发酵性能产生负面影响。在这项研究中，我们评估了乙酸对利用木糖异构酶途径的高效工程化木糖利用酿酒酵母 SXA-R2P-E 发酵葡萄糖和木糖的抑制作用。乙酸的存在严重降低了该菌株的木糖发酵性能。然而，通过添加金属离子可以缓解乙酸胁迫，从而在 2g/L 的乙酸胁迫下使乙醇的生产速率提高了 52%。本研究表明了乙酸对工程化的基于异构酶的木糖利用菌株的抑制作用，并提出了一种简单而有效的方法，可在乙酸胁迫下改善协同发酵性能，从而高效生产生物乙醇。
