拮抗菌SB1的鉴定及其抗菌物质的分析

Identification of Antagonistic Bacterium SB1 and Analysis on Its Antibacterial Substance

摘要:

对番茄根系菌株SB1的抗菌活性进行测定, 结果表明该菌株对多种植物病原真菌、细菌具有明显的抑制作用, 表现出广谱抗菌活性。通过菌体形态、生理生化反应及16S rDNA序列分析, 鉴定菌株SB1为枯草芽孢杆菌内生亚种。以青枯雷尔氏菌为指示菌, 测定了菌株SB1抗菌物质的理化性质及组成。结果表明, 其抗菌物质表现出良好的热稳定性、水溶性和醇溶性, 且对紫外线照射和蛋白酶K处理不敏感。高效液相色谱分析结果进一步显示菌株SB1的抗菌物质中含有抗菌肽Surfactin。

Abstract:

A bacterial strain SB1, isolated from tomato roots, was tested for its antimicrobial activities. Results indicated that strain SB1 showed strong inhibitory activities against various plant pathogenic fungi and pathogenic bacteria, exhibiting wide antimicrobial spectrum. Strain SB1 was identified as Bacillus subtilis subsp. endophyticus based on its morphological, physiological characteristics and 16S rDNA sequence. In addition, properties of antibacterial substances of strain SB1 were examined using Ralstonia solanacearum as an indicator. The results showed that antibacterial substances were heat-stable, water-soluble, alcohol-soluble, and resistant to ultraviolet radiation and protease K. High performance liquid chromatography (HPLC) results further suggested that one of the antibacterial substances was surfactin.