侧孢短芽孢杆菌 BL-21产抗菌物质发酵条件的研究

目的]侧孢短芽孢杆菌菌株 BL-21是一株生防菌，对烟草赤星、小麦赤霉以及稻瘟病菌等多种植物病原真菌具有抑制菌丝体生长的作用。将侧孢短芽孢杆菌的培养基进行优化，可提高抗菌物质的产量。方法]通过单因子试验对菌株 BL-21产抗菌物质的条件及培养基成分进行了优化，并对指示菌进行筛选。结果]通过试验得到最适指示菌为烟草赤星病菌，最优的培养条件为，培养基初始 pH值8.0、培养温度30℃、装液量90 ml/250 ml、转速180 r/min、发酵时间48 h，并明确了以葡萄糖作为碳源，以牛肉膏作为氮源最有利于抗菌物质的产生。加入5 g/L NaCl和0.2 g/L MnSO4可提高抗菌物质的产量。结论]优化的培养基更有利于抗菌物质的产生，为今后的进一步研究奠定良好的基础。

Studies on Fermentation Conditions of Antimicrobial Substances Produced by Brevibacillus laterosporus BL-21

Objective] Brevibacil us laterosporus BL-21 was inhibitory to Gibberel a sanbinetti, Fusarium graminearum Magnaporthe grisea and many other phy-topathogenic fungi. Antimicrobial substances can be increased through optimizing the medium of Brevibacil us laterosporus. Method] A total of 10 factors were tested for their function of improving antibiotics yield of BL-21 by single-factor test. And the indicative bacterium was screened. Result] The best indicative bacterium was Al-ternaria solani, the optimum process parameters in shaking flask on fermentation consisted of initial pH of 8.0, culture at 30 ℃, loadage 90 ml/250 ml, rotation 180 r/min, and fermentation time of 48 h. The results also indicated that glucose was the best carbon source for the antibiotics productivity of BL-21, and beef extract was the best nitrogen source. In addition, univalent ion Cl＋ and divalent ion Mn2＋ stimu-lated BL-21 antibacterial active component biosynthesis. Conclusion] Optimized medi-um is more conducive to produce antimicrobial substances.