Studies on development of a new production method for anti-cancer agent, taxol by use of pestalotiopsis sp.

以一株产紫杉醇真菌为研究对象，通过对该真菌进行突变和细胞融合，通过改变培养条件和其他方法提高紫杉醇产量。并用新分离的红豆杉属树木内皮真菌对紫杉醇产率进行了测定。得到了以下结果：(1)提高紫杉醇产量的试验：将培养方法由站立培养改为摇培养和固定化培养。然而，紫杉醇产量约为静置培养的1/10。通过改变培养基中糖的组成和糖的添加量，考察了糖作为生物前体对紫杉醇生产的影响。结果表明，在培养基中添加葡萄糖和少量肌醇可使紫杉醇产量提高1.3倍。并尝试通过添加生物基因抑制剂来提高紫杉醇的产率。但是，生产率却无法提高。此外，还考察了紫杉醇产量对培养基中氮添加量变化的影响。结果表明，氮肥用量减少1/10，紫杉醇产量提高1.3倍。通过真菌的培养，发现除紫杉醇外，还产生了一种紫杉醇类化合物（结构已明确）。(2)利用紫外照射和化学试剂使真菌发生突变。但是，每种突变菌在培养基中孵育时，紫杉醇产量并没有增加。并通过原生质体融合，尝试形成具有较高紫杉醇产率的融合体。目前正在进行融合体培养产紫杉醇的研究。(3)提高紫杉醇产量：发现在生物反应器中，通过真菌发酵生产紫杉醇与固定化细胞培养生产紫杉醇结合使用，紫杉醇的产量大大提高。并对从红豆杉属树木中新分离到的几种真菌的紫杉醇产率进行了研究。发现一种新真菌的紫杉醇产率高于研究中使用的真菌。此外，还发现东北红豆杉树皮内真菌产生的紫杉醇的抗真菌活性与木材提取物的抗真菌活性有关。少

Using a taxol producing fungus isolated from Kyaraboku (Taxus cuspidata var. nana), improvement of taxol productivity by change of incubation conditons and othe methods by mutation and cell fusion of the fungus were conducted. And, taxol productivity was examined by the newly isolated fungi from inner bark of genus taxus trees. The following results were obtained.(1)The trial for increase in the taxol productivity : Culture methods were changed from standing cultures to shaking and immobilized cultures. However, the taxol productivity was about 1/10 times to the standing cultures. Effect of sugar as a biogenetic precursor on taxol production was examined by change the sugar composition and added amount of sugar in the medium. It was found that taxol productivity was increased 1.3 times when glucose and small amount of myoinositol was added to the culture. And, taxol productivity was tried to increase by addition of a biogenetic inhibitor. But, the productivity could not be increased. F … More urthermore, the effect of taxol productivity on change of added amount of nitrogen in the culture medium was examined. It was found that taxol productivity was increased 1.3 times when the amount of nitrogen was decreased 1/10 times. It was found that a kind of taxane compound (elucidated the structure) was produced except for taxol by the culture of the fungus.(2)The fungus was made to mutate by ultraviolet irradiation and chemical reagent. But, taxol productivity was not increased when each mutation fungus was incubated in the culture medium. And, the formation of fusants having higher taxol productivity was tried by protoplast fusion of the fungus. The taxol productivity by cultures of the fusants is being conducted.(3)Increase in taxol productivity : It was found that taxol productivity was drastically improved, when taxol production by fermentation of the fungus is used jointly with taxol production by immobilized cell cultures of Kyaraboku in a bioreactor. And, taxol productivity of some newly isolated fungi from genus taxus trees was examined. It was found that one newly fungus had higher taxol productivity than the fungus used in the research. And furthermore, it was found that antifungal activity of taxol produced by the fungus present in inner bark of Taxus cuspidata van nana are related to the antifungal activity of wood extracts. Less