Development of Green Chemistry for Syntheses of Polysaccharide-Based Materials

本课题拟以可再生天然多糖为平台，以嗜热酶库为新型合成工具，发展环境友好化学，合成新型po！ysaccharide-based材料。主要的推动力是嗜热酶催化的发展和应用。来自极端环境（如高温、高压或高盐浓度）的微生物的极端酶库构成了一种新型的生物催化剂，它表现出新的化学、区域和立体选择性，可以在极端温度或pH或工业加工中的有机溶剂中使用。本项目的具体目标和预期结果是：利用嗜热性糖苷酶文库获得糖苷酶催化糖基化的完整数据库，并合成一系列单糖修饰多糖。2. 利用嗜热纤维素酶库合成结构明确的纤维素衍生物，可用于研究多糖的结构/性质关系。3. 发展了亲热性脂肪酶/酯酶催化聚合技术，将聚酯接枝到多糖上，合成了一系列新型的多糖-聚酯材料。该项目将示范和促进环境友好型生物催化的使用，将可再生自然资源转化为新型材料。＊＊＊

9728366 Wang The proposed research program uses renewable natural polysaccharides as a platform, and uses thermophilic enzyme libraries as a novel synthetic tool to develop environmentally friendly chemistry for the synthesis of novel po!ysaccharide-based materials. The major thrusts are the development and application of thermophilic enzyme catalysis. Extremozyme libraries from microorganisms in extreme environments (e.g. high temperature, high pressure or high salt concentration) constitute a new type of biocatalysts, which exhibit novel chemo-, regio- and stereo- selectivities and can be used at extremes of temperature or pH or in organic solvents in industrial processing. The specific aims and expected results for this program are: 1. Obtain a complete data base on glycosidase-catalyzed glycosylation with the thermophilic glycosidase library and synthesize a host of monosaccharide modified polysaccharide. 2. Utilize the thermophilic cellulase library to synthesize structurally well defined cellulose derivatives which can be used to study the structure/property relation of polysaccharides. 3. Develop thermophilic lipase/esterase-catalyzed polymerization technology to graft polyesters onto polysaccharides, and synthesize a host of novel polysaccharide-polyester materials. This program will serve to demonstrate and promote the use of environmentally friendly biocatalysis to transform renewable natural resources into novel materials. ***