导　　师： 郭祀远;李琳

学科专业： 082202

授予学位： 博士

作　　者： ;

机构地区： 华南理工大学

摘　　要： 裂褶多糖/(Schizophyllan/)是一种生物反应调节剂,它在临床应用上表现出良好的抗肿瘤活性。此外,裂褶多糖独特的理化性质还展示其在食品、保健品、药物载体、化妆品等领域应用的前景。而目前对于其应用方面的基础研究及化学改性研究不多,制约了裂褶多糖的应用。本论文对裂褶菌的培养、裂褶多糖的制备方法以及应用方面的理化特性等展开系统的研究,对裂褶多糖的化学改性及构效关系进行探讨,将为促进裂褶多糖的开发,并为提升多糖产品的应用价值提供理论基础。主要研究内容和结果如下: 1.裂褶菌的形态变化和产多糖规律 通过外部形态观察和显微观察对裂褶菌不同培养条件下菌丝形态变化进行研究,结合对裂褶多糖、还原糖等发酵参数的测定,发现裂褶菌胞外多糖的合成呈半生长偶联型,且多糖的产量和菌体形态有关,通过控制溶氧或搅拌使发酵时菌丝形成较多“有效生长点”,可以在较低的生物量下提高胞外裂褶多糖的产量。 2.克量级裂褶多糖的快速纯化及其结构鉴定 裂褶菌发酵液经离心除菌体,活性炭脱色,Sevag法脱蛋白,乙醇沉淀,透析,50kD膜包浓缩和冷冻干燥,可得到均一的裂褶菌胞外多糖,该方法适合于对克量级的裂褶多糖进行纯化。 采用UV、IR、HPLC、GC-MS、1H NMR和13C NMR对Sc1菌株分泌的裂褶多糖的结构进行鉴定,确证其结构为β-/(1→3/)主链上每隔3个葡萄糖单元产生一个β-/(1→6/)分支,GPC法测得其重均分子量和数均分子量分别为2.5×107和1.2×107,为进一步的应用提供基础数据。 3.裂褶多糖的理化特性 采用乌式粘度计、旋转粘度计、GPC对裂褶多糖分子量的测定方法,以及粘度和构象之间的关系展开研究,通过文献数据,完善粘度法测定裂褶多糖分子量的公式。 通过控制干燥器内湿度的方法测试裂褶多糖的吸湿� Schizophyllan is one kind of biological response modifiers. It shows good antitumor activity in clinical application. Schizophyllan also shows bright future in the application of food, drug carrier, cosmetics for its particular physical and chemical characteristics. While few research were carried out for the fundamental study about application and chemical modification of Schizophyllan, these factors have an enormous restriction to the further application of Schizophyllan. The culture of Schizophyllum commune, the purification method and typical physical and chemical characteristcs of Schizophyllan were systematically researched and its chemical modification and the relationship of structural and function were discussed. It was aimed to set theory ground for the development of Schizophyllan and improving the use value of polysaccharide product. The main contents and results are as follows: 1. Morphology variation of Schizophyllum commune and secreted rules of Schizophyllan The morphology variation of Schizophyllum commune under different cultured conditions were researched by direct observation and micrographs. Combined with the determination of fermentation parameters such as the content of polysaccharide, reduced sugars and biomass, it was indicated that the synthesis of extracelluar polysaccharide in Schizophyllum Commune is with growth coupling and the yield of Schizophyllan is related with the morphology of mycelial. The yield of Schizophyllan can be improved with more“efficient growing points”by the control of dissolved oxygen and agitation. 2. Rapid purification method of gram scale Schizophyllan and its structural identification Homogeneous polysaccharide can be obtained by following procedures involved centrifugation of suspensions from fermentation, followed by decolouring with activated carbon, removing protein by Savage method, precipitating with ethanol, dialysing,concentrating by 50kD ultramembrane and freeze-drying. This process is a rapid way for the purification of Schizo

关 键 词： 裂褶多糖 分离纯化 理化特性 化学改性 抗肿瘤活性

领　　域： [化学工程]