【摘要】 本研究通过对变棕溶杆菌Lysobacter brunescens OH23菌株发酵产物的拮抗谱进行检测,发现其发酵产物对黄单胞属植物病原细菌具有特异拮抗活性,并且对水稻黄单胞菌不同菌株的拮抗活性存在差异。本研究进一步对OH23次生抗菌物质稳定性进行了分析,发现OH23产生的次生抗菌物质对高温、紫外光照、蛋白酶、非强碱性环境均表现稳定,但在强碱性环境（pH 11.0）下拮抗活性丧失。最后,采用单因素试验和正交试验设计对OH23发酵培养基组分进行了优化,最终确定OH23高产次生抗菌物质的培养基配方为高聚蛋白胨5 g/L、酵母粉5 g/L、可溶性淀粉6 g/L、FeSO₄·7H₂O 15 mg/L、ZnSO₄·7H₂O 5 mg/L。更多还原

【Abstract】 In this study,the antimicrobial spectrum of secondary metabolites of Lysobacter brunescens OH23was tested.The results showed that OH23 was a potential biocontrol strain with specific activity against Xanthomonas sp.At the same time,the secondary metabolites of OH23 showed different antagonistic activity against different strains of Xanthomonas oryzae.Stability test indicated that the active secondary metabolites were stable with high temperature,ultraviolet light,protease and non-strong alkaline environment.However,the antagonistic activity almost completely lost under strong alkaline conditions（pH=11.0）.Single factor test and orthogonal design were used to screen and optimize the carbon source,nitrogen source and metal ion of OH23fermentation medium.The final formulation for high yield of active secondary metabolites included high polypeptone at 5 g/L,yeast powder at 5 g/L,soluble starch at 6 g/L,FeSO₄·7H₂O at 15 mg/L and ZnSO₄·7H₂O at5 mg/L.更多还原