氧气对木质纤维素来源抑制物的生物脱毒促进机制研究

项目名称： 氧气对木质纤维素来源抑制物的生物脱毒促进机制研究

项目编号： No.21306048

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 化学工业

项目作者： 张建

作者单位： 华东理工大学

项目金额： 25万元

中文摘要： 木质纤维素在生物加工过程中会过度降解生成多种化合物（包括呋喃类、有机酸类和酚酸类物质），它们对后续的酶水解和发酵都有很强的抑制作用。生物脱毒是利用微生物或酶制剂来降解这些抑制物，具有脱毒彻底、无废水排放等优点，但3天以上的脱毒周期严重限制了该方法的应用。前期研究表明，通氧可以明显缩短树脂枝孢霉Amorphotheca resinae ZN1的脱毒时间，但其作用机制尚不清楚。本课题拟从氧气对树脂枝孢霉生长和对抑制物代谢速率的影响两方面入手，通过qPCR的方法建立菌体量与菌体特征性酶编码基因量之间的关联，实时快速监测生物脱毒过程的菌体量变化，确定氧气-菌体量-脱毒速率三者的关系；通过唯一碳源实验对抑制物的降解路径进行表征，用qRT-PCR的方法分析氧气引起的关键酶基因表达差异，阐明氧气在抑制物代谢中的作用。本项目的实施将为脱毒反应器的开发提供依据，为"脱毒-发酵"整合细胞的构建提供良基因来源。

中文关键词： 木质纤维素；生物脱毒；树脂枝孢霉A. resinae；氧气；辅因子

英文摘要： A variety of degradation products (including furan derivatives, organic acid and phenolic acid compounds), which have a stong inhibition on the following enzymatic hydrolysis and microbial fermentation, generated in the lignocellulose bioprocessing. Biodetoxification uses microorganisms or their secreted enzymes to metabolize these inhibitors.Compared with other detoxification methods, biodetoxification has many advantages, including complete inhibitors-removal, non-waste water disposal and etc. However, longer than 3 days biodetoxification period restricted its extensive application in the practical bioprocessing. Our previous study showed that the oxygen supply during biodetoxification could greatly improve the inhibitors degradation rates and shorten the biodetoxification period of Amorphotheca resinae ZN1 within 24 hours, but the underlying mechanisms were still unknown. This study aims to uncover the promoting mechanisms of oxygen supply from two aspects, the effect on growth of A. resiane ZN1 and the inhibitors degradation rates. For the former, the newly rapid and accurate biomass assay method for solid-state fermentation will be developed through corelation the quantity of characteristic enzyme encoding gene by qPCR to its colony forming units (CFU) in the pure synthetic medium. Then the biomass of A. re

英文关键词： lignocellulose；biodetoxification；Amorphotheca resinae ZN1；oxygen；cofactor