目的 对近缘毛壳Chaetomium subaffine菌株LB-1产生抑菌物质的部位及提取方法进行研究，为开发生防菌株LB-1防治植物病害奠定基础。方法 以番茄灰霉病菌Botrytis cinerea和玉米大斑病菌Exserohilum turcicum为指示菌，采用平板密封培养法检测菌株LB-1是否产生挥发性抑菌物质；采用菌体超声破碎和液态培养的方式检测菌株LB-1产生的非挥发性抑菌物质存在的部位；采用含毒培养基法和滤纸片法检测菌株LB-1培养液的硫酸铵沉淀、盐酸沉淀和有机溶剂萃取物的抑菌效果，以确定菌株LB-1培养液中抑菌物质的提取方法。结果 菌株LB-1与2种供试病原菌密封共培养时，对病原菌的生长没有明显影响，表明菌株LB-1不能产生挥发性抑菌物质。菌株LB-1菌体胞内提取物的抑菌活性与对照无差异，但其培养液对B. cinerea和E. turcicum的生长有较强的抑制作用，表明菌株LB-1产生的抑菌物质存在于菌体细胞外。菌株LB-1培养液的硫酸铵沉淀和盐酸沉淀对2种供试植物病原真菌的生长均无抑制效果，但有机溶剂萃取可获得菌株LB-1培养液中的抑菌物质，其中正丁醇萃取物抑菌效果最好，当其质量浓度为0.1 mg/mL时，对B. cinerea和E. turcicum的生长抑制率分别高达59.80%和58.37%。结论 菌株LB-1通过产生胞外非挥发性物质抑制植物病原真菌的生长，培养液中的抑菌物质可通过正丁醇萃取获得。
Objective The existing position and extraction method of antifungal substance produced by Chaetomium subaffine strain LB-1 were studied in order to lay a foundation for the development of the strain LB-1 to control plant diseases.Method With Botrytis cinerea and Exserohilum turcicum as test plant pathogens, the sealed plate assay was used to detect whether the strain LB-1 could produce volatile antifungal substance. The hyphae ultrasonic breaking and liquid culture methods were used to detect the existing position of nonvolatile antifungal substance produced by the strain LB-1. The extraction method of antifungal substance was determined by detecting the inhibitory effects of ammonium sulfate precipitation, hydrochloric acid precipitation and organic solvents extracts of strain LB-1 culture broth via poison plate assay and filter paper disc assay.Result The strain LB-1 did not have obvious inhibitory effect on the growth of the two test plant pathogens when being co-cultured in a sealed plate with each plant pathogen, indicating that strain LB-1 could not produce volatile antifungal substance. The antifungal activity of the intracellular extract of the strain LB-1 was not different from that of the control, but its culture broth had a strong inhibitory effect on B. cinerea and E. turcicum, indicating that the antifungal substances produced by the strain LB-1 existed outside the mycelium. Neither ammonium sulfate precipitate nor hydrochloric acid precipitate of strain LB-1 culture broth showed inhibitory effect on B. cinerea and E. turcicum, but the organic solvent extract of strain LB-1 culture broth showed antifungal effect, and the inhibition rate of n-butanol extract was the highest. When the concentration was 0.1 mg/mL, the inhibition rates against B. cinerea and E. turcicum growth were 59.80% and 58.37% respectively.Conclusion The strain LB-1 inhibited the growth of plant pathogenic fungi by producing extracellular nonvolatile antifungal substances, and the antifungal substance in the culture broth can be extracted by n-butanol.
刘彩云,高秀清,赵静.近缘毛壳Chaetomium subaffine LB-1抑菌物质存在部位及提取方法[J].华南农业大学学报,2023,44(2):280-286复制