In this study, a liquid medium for culturing poplar endophytic Chaetomium globosum ND35 was optimized with an orthogonal design of L16 (45). Physical and chemical characteristics of antifungal substances from C. globosum ND35 were preliminarily analyzed by pH paper chromatography and Jack's eight solvents system paper chromatography as well as UV-Vis spectrum. Bioactive fractions in crude extracts were separated by thin-layer chromatography (TLC) and high performance liquid chromatography (HPLC) and their inhibition to Valsa sordita was examined in agar plate. At the same time, dynamics of the antifungal substances in liquid culture were also tested. The results showed that an optimal medium was obtained with 1％ dextrose, 1％ sucrose, 0.5％ beef extract, 0.02％ ferrous sulfate, 0.01％ vitamin B1,pH 7 value. Both intracellular and extracellular substances of liquid cultured mycelia had antibiotic activity, with good heat stability. The antifungal substance were of weak polarity, and able to be easily dissolved in organic solvent, but hard in water relatively. C. globosum ND35 antibiotics had a maximum absorption peak at 221 nm, composed of four components which all showed antifungal activity to Valsa sordita. Analysis of growth dynamics showed that output,absorbency, pH and inhibition rate of the antibiotics were continuous changing in the liquid fermentation process.%以杨树内生真菌球毛壳ND35为供试菌株,采用L<,16>(4<'5>)正交试验法对液体培养基进行优化;利用pH纸色谱、捷克八溶剂系统纸色谱方法及紫外-可见光谱扫描法对该内生菌的抗生物质进行理化性质初步分析;用薄层层析、高效液相色谱及平板抑菌法检测分析该菌粗提液的活性成分及对杨树腐烂病菌的抑菌效果;对抗生物质液体培养的主要动力学指标进行分析.结果表明:优化后培养基配方为:1%葡萄糖,1%蔗糖,0.5%牛肉膏,0.02%硫酸亚铁,0.01%维生素B<,1>,pH值为7.球毛壳ND35菌株的抑菌作用分为活菌体的抑菌作用和代谢活性物质的抑菌作用,液体培养后的菌丝胞内和胞外均产生抗生物质,并具有较好的热稳定性.该抗生物质pH值为7,易溶于有机溶剂,难溶于水.球毛壳ND35抗生物质在221 nm处有最大的吸收峰,该抗生物质有4个组分,均对杨树腐烂病菌有抑菌活性.生长动力学表明,在液体发酵培养过程中,球毛壳ND35抗生物质的产量、吸光值、pH及其抑菌率是连续变化的.
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