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用同步培养和异步培养从91株大气腐生菌中筛选出13株对9种植物病原细菌有抑制作用的拮抗菌株,其中Bacillus cereus G35菌株的去菌上清液经硫酸铵沉淀、透析去盐、Sephadex G-50凝胶过滤,所得分段收集液对280nm有两个明显的吸收峰,抑菌活性与第二吸收峰吻合,对蛋白酶E和蛋白酶K敏感,对100℃温度处理10min和酚抽提处理敏感,对胰蛋白酶部分敏感,对核糖核酸酶及温度60℃,80℃ 30min处理稳定,其活性物质提取量在一定范围内随硫酸铵饱和度提高而增大。培养基种类、温度、培养时间对该菌株产生拮抗物有不同程度影响,在KMB培养液中30℃振荡培养18h后,拮抗物产生达到稳定,紫外线处理能促进洁抗物产生。此外,还报道了有关B.cereus G35变异株G35-M的某些研究结果。
Thirteen antagonistic strains were screened from 91 strains of atmospheric saprophytes using synchronous culture and asynchronous culture. The bacteriostatic supernatant of Bacillus cereus G35 was precipitated by ammonium sulfate, dialyzed and desalted, Sephadex G-50 gel filtration, the resulting fraction collected liquid 280nm have two obvious absorption peak, antibacterial activity consistent with the second absorption peak, sensitive to proteinase E and proteinase K, 100 ℃ temperature treatment 10min and phenol pumping Sensitive to treatment and sensitive to trypsin, stable to ribonuclease and temperature of 60 ° C and 80 ° C for 30 minutes. The amount of active substance extracted increased with the increase of ammonium sulfate saturation within a certain range. The antagonism of this strain was affected to varying degrees by the type of culture medium, temperature and culture time. After shaking culture at 30 ° C for 18h in KMB medium, the production of antagonist was stable. Ultraviolet treatment could promote the production of antibiotics. In addition, some studies on B.cereus G35 mutant G35-M were also reported.