A facile pretreatment strategy for recovering sugars and lignin effectively from a variety of lignocellulosic feedstocks

0933250 Varanasi知识产权优点：植物生物质可以为未来的“生物精炼厂”提供可持续的原料，部分取代传统的石化精炼厂。PI计划利用离子液体（IL）的溶剂化特性来克服纤维素和生物质对酶水解的抑制作用，这是经济和可持续生物燃料生产的核心障碍。水解产物可用作乙醇生产的发酵原料或用作生产其他化学品的糖平台。在适当选择酶的情况下，IL处理的纯纤维素的水解初始速率比未处理的纤维素的水解初始速率高近2个数量级。与替代的预处理方法相比，生物质中纤维素的转化也显著加速。拟议的研究旨在系统地评估和优化应用于生物质的预处理过程，以最大限度地减少化学和能源投入。为了实现这一目标，需要清楚地了解离子液体预处理生物质的结构和化学变化以及这些变化对后续水解的影响。为了达到这一目的，将解决以下具体目标：（1）评估影响生物质糖化动力学和产物产率的基本因素，以优化预处理。(2)工程化水解酶混合物以优化IL预处理的生物质的己糖和戊糖产率。(3)回收和再循环糖化酶和离子液体，并评估生物质的未水解部分用于木质素回收。更广泛的影响：离子液体有可能将木材和草转化为燃料和化学品生产的可行原料。离子液体没有可测量的蒸汽压，并且由于其对空气质量的影响可以忽略不计而被认为是绿色的。该项目的一个重要组成部分是研究生和本科生的培训和教育，他们将在生物化学方法，分析技术，离子液体合成，表征和评估木质纤维素材料的化学和结构变化方面获得相当多的经验，这是一个非常复杂的系统。该项目的跨学科性质将使研究生和本科生研究人员获得广泛的培训。 示范模块和背景材料将在生物燃料中开发，以整合到UTube中，该网站由我们的合作者Jared安德森博士领导。该网站将包含一系列视频演示的链接，这些视频演示由合作研究者和本科研究人员为中学生量身定制。PI和Co-PI的曾担任高中和本科生的研究导师。其中一个参加了NSF青年学者计划，向经济困难的学生介绍工程。另一个作为女工程师协会的教员顾问参与了外联活动，并通过参与美国教育部赞助的GEARUP和EXCEL方案，向非洲裔美国人和拉丁美洲中学生介绍动手工程项目。

0933250VaranasiSummary Intellectual Merits: Plant biomass can provide a sustainable feedstock for future "biorefineries" partially replacing conventional petrochemical refineries. The PI plans to capitalize on the solvation properties of ionic liquids (ILs) to overcome the recalcitrance of cellulose and biomass to enzymatic hydrolysis, a core barrier to economical and sustainable biofuels production. The hydrolyzate can be used as a fermentation feedstock for ethanol production or as a sugar platform for production of other chemicals. With the proper selection of enzymes, initial rates of hydrolysis for IL treated pure cellulose are nearly 2 orders of magnitude greater than those of untreated cellulose. Conversion of cellulose in biomass is also substantially accelerated in comparison to alternative pretreatment methods. The proposed research seeks to systemically assess and optimize the pretreatment process applied to biomass with the aim of minimizing chemical and energy inputs. To achieve this, a clear understanding of the structural and chemical changes in biomass with ionic liquid pretreatment and the effects of those changes on subsequent hydrolysis is needed. The following specific objectives will be addressed to achieve this end:(1) Assess fundamental factors which affect kinetics and product yield for biomass saccharification to optimize pretreatment. (2) Engineer the hydrolyzing enzyme mixture to optimize hexose and pentose sugar yields from IL-pretreated biomass. (3) Recover and recycle saccharification enzymes and ionic liquids and assess unhydrolyzed portions of biomass for lignin recovery. Broader impacts: Ionic liquids have the potential to convert wood and grasses into viable feedstocks for fuel and chemical production. Ionic liquids have no measurable vapor pressure and are considered green due to their negligible impact on air quality. An essential part of this project is the training and educating of graduate and undergraduate students, who will obtain considerable experience in biochemical methods, analytical techniques, ionic liquid synthesis, characterization, and assessment of chemical and structural changes in lignocellulosic materials, a very complex system. The interdisciplinary nature of this project will allow graduate and undergraduate researchers to acquire a broad-based training. Demonstration modules and background material will be developed in biofuels for integration into UTube, a site spear-headed by our collaborator Dr. Jared Anderson. The site will contain links to a series of video demonstrations performed by the co-investigators and undergraduate researchers tailored to middle school children. The PI and Co-PI's have served as high school and undergraduate student research mentors. One has participated in the NSF Young Scholars program, to introduce economically disadvantaged students to engineering. The other has been involved in outreach activities as the faculty advisor to the Society of Woman Engineers and through involvement in the GEARUP and EXCEL programs sponsored by the US Department of Education to introduce African American and Latino middle and high school students to hands-on engineering projects.