【作者】 杜华；

【导师】 李洪连；

【作者基本信息】 河南农业大学 ， 植物病理学， 2004， 硕士

【摘要】 从针对防治小麦纹枯病的100多种生防放线菌中，筛选出了目标放线菌024。对它的菌种的初步鉴定、初始发酵条件与最适发酵条件进行了探索，找到了适合该菌大量产生抗生素的发酵条件（装液量100ml/250ml，黄豆饼浸液培养液发酵培养，初始PH7.0，转速170r/min，28℃培养，培养时间4d）及其它影响因子，包括PH值、温度、金属离子等，本文主要对该菌株种类鉴定及其所产抗生素的纯化技术、结构分析等方面进行了研究。采用经典鉴定方法和分子分类方法对放线菌024进行了鉴定，结果表明，放线菌024属于链霉菌属，并且和淀粉酶产色链霉菌（Streptomyces diastatochromogenes）、疮痂病链霉菌（Streptomyces scabies）两个种有99％的同源性；024菌株的形态及培养特征与Streptomyces diastatochromogenes基本一致但略有不同，生理生化测定也有所差异，所以确定放线菌024是链霉菌属Streptomyces diastatochromogenes的一个变种。抑菌谱测定表明放线菌024的发酵液对多种植物病原菌，如：苹果炭疽病菌(Colletotrichum gloeosporioides)、小麦赤霉病菌(Fusarium gramiaearum)、小麦根腐长孺孢(Helminthosporium sativum)、棉花黄萎病菌(Verticillium dahliae) 、山药炭疽病菌(Colletotrichum gloeosporioides)等有良好的抑制效果。放线菌024的发酵物质—抗生素纯化研究结果表明，通过发酵培养、过滤、浓缩、灭菌、离心等预处理，然后用甲醇浸取，上清夜上氧化铝和硅胶柱层析即连续柱层析可以有效地对抗生素进行纯化。氧化铝柱层析中用丙酮、丙酮+甲醇（1：1）、甲醇各150ml作为洗脱液；硅胶柱层析中用甲醇：水（1：1）250ml作为洗脱液。在连续柱层析<WP=8>收集的洗脱液中，有两个区段对禾谷丝核菌(Rhizoctonia cerealis)有较好的抑菌活性，水浴锅中挥发蒸干后得到粗提制品，该晶体对禾谷丝核菌有很强的抑菌活性。通过紫外吸收光谱、红外吸收光谱、核磁共振波谱（核磁共振氢谱、核磁共振碳谱）、质谱分析法对连续柱层析所得的晶体进行结构鉴定，结果表明晶体的主要成分是一种二聚糖，分子量382.6；另外有一种物质分子量1153.5, 有关结构正在分析中。更多还原

【Abstract】 024 strain, which was screened from many Actinomycetes, inhibits Rhizotonia cerealis intensely which can cause Wheat sharp eyespot. Its initial and optimal fermentation condition of production of antifungal substance have been studied, and found the the optimal condition (the initial pH of medium 7.0, 100ml liquid medium in 250ml flask, fermentation temperature 28℃, 170rpm for 4 days, soybean cake culture medium) and other influencing factor such as the temperature, metal hydronium. This paper studied the identification of the 024-strain of Actinomycetes and the purification and structural analysis on its antibiotic. The 024-strain of Actinomycetes was idientified as a new species of the Streptomyces through the classical and molecular methods. The antifungal spectrum of 024-antibiotic includes many plantpathogenic fungi, such as Colletotrichum gloeosporioides, Fusarium gramiaearum, Helminthosporium sativum, Helminthosporium maydis, Verticillium dahliae, Colletotrichum gloeosporioides..Different extracting and purifing methods were taken, such as organic solvent extraction, alumina column chromatography and silica gel column chromatography etc.. The effective approach was found that, first, the 024-antibiotic was dealt with the primary methods—fermentation, filtration, condensation, disinfection and so on, then it can be purified by methyl alcohol soaking, alumina and silica gel column <WP=73>chromatography. The acetone, methyl alcohol, germfree water and their mixed liquor were used in different column chromatography. In the continuous column chromatography (alumina and silica gel column chromatography), there are two part which have antifungal effect on Rhizotonia cerealis . After the evaporation, we get the crystal of this antibiotic, which has strong antifungal effect.Through the advanced equipment ,such as ultraviolet radiation, infrared, the crystal of this antibiotic was identified.The result shows that the primary component is a sort of disaccharide and its molecular weight is 382.6, otherwise there is the other substance, whose molecular weight is 1153.5 and its structure is been studying.更多还原