枯草芽孢杆菌B47菌株抗菌物质的分离纯化及其对玉米小斑病的防治作用

Purification of Antimicrobial Substance Produced by Bacillus subtilis B47 and Its Effect on Southern Corn Leaf Blight

枯草芽孢杆菌Bacillus subtilis菌株B47为番茄内生细菌,能产生对多种植物病原菌有抑制作用的抗菌物质。通过盐酸沉淀、甲醇抽提、硅胶柱层析、凝胶过滤层析和反相高效液相色谱(RP-HPLC)法提取和纯化到该抗菌物质。理化性质测定结果表明,该物质热稳定性和抗紫外线稳定性好;在碱条件下稳定;对蛋白酶不敏感;能溶于甲醇;双缩脲反应呈阳性,茚三酮反应呈阴性,但经酸水解后茚三酮反应呈阳性,推测该物质可能为环肽类物质。该物质对测试的14种病原真菌有拮抗作用,其中,对玉米大小斑病菌和各种香蕉叶斑病菌的拮抗作用强,但对供试病原细菌无拮抗作用。该抗菌物质在0.3g.L-1浓度下对玉米小斑病的田间防治效果为53.05%。

Bacillus subtilis B47 is an endophytic bacterium of tomato,and produces a substance to inhibit some plant pathogens.The antimicrobial substance was extracted and purified by hydrochloric acid precipitation,methanol extraction,silica gel column chromatography,gel filtration chromatography and reversed phase high performance liquid chromatography.The purified substance was stable to alkaline,heat,protease and UV.It could dissolve in methanol.The substance showed positive reaction to biuret and negative reaction to ninhydrin,but showed positive reaction to ninhydrin when it was hydrolyzed with acid.All the data above indicated that the substance could be ring peptide.The growth of 14 plant pathogens could be inhibit by the substance,among which,the pathogens of the northern corn leaf blight,southern corn leaf blight and banana leaf spot were inhibited strongly,while no inhibition to the tested bacterial pathogens.Control efficacy of antimicrobial substance produced by Bacillus subtilis B47 at 0.3 g·L-1 on the southern corn leaf blight in field was 53.05%.