海洋细菌GM-1-1产芽孢发酵培养基和摇瓶发酵条件优化

Optimization of fermentation medium for spore production and flask-shaking fermentation conditions of marine bacteria GM-1-1

【目的】优化海洋解淀粉芽孢杆菌(Bacillus amyloliquefaciens)GM-1-1的产芽孢发酵培养基和摇瓶发酵条件,为该菌株的开发和应用提供理论依据。【方法】以GM-1-1菌株发酵液中的细菌总数和芽孢产率为检测指标,采用单因素和正交试验对该菌株产芽孢发酵培养基和摇瓶发酵条件进行优化;GM-1-1菌株发酵完成后喷雾干燥制成菌粉,加入不同助剂制成有效含量为1010CFU/g的可湿性粉剂用于水稻纹枯病田间防治试验。【结果】GM-1-1菌株产芽孢最佳发酵培养基配方为麦麸0.75%、花生饼粉2.5%、CaCO30.05%;最佳发酵条件为pH 7,温度30℃,250 mL三角瓶装液量60 mL,接种量8%,转速200 r/min,培养时间54 h。优化后GM-1-1菌株发酵培养基的细菌总数和芽孢产率分别达7.40×109个/mL和89.42%。田间防治试验结果表明,GM-1-1可湿性粉剂对水稻纹枯病的防治效果最高可达82.06%。【结论】优化后的培养基和发酵条件可有效提高GM-1-1菌株的细菌总数和芽孢产率,且培养基成本低、来源广泛。GM-1-1可湿性粉剂对水稻纹枯病有较好的防治效果,可用于生产菌剂并推广应用。

【Objective】Fermentation medium for spore production and flask-shaking fermentation conditions of Bacillus amyloliquefaciens GM-1-1 were optimized,in order to provide theoretical references for exploitation and application of GM-1-1 strain.【Method】Total number of bacteria and spore production rate in fermentation broth of GM-1-1strain were set as test indexes.And fermentation medium for spore production and flask-shaking fermentation conditions of GM-1-1 strain were optimized by using single factor and orthogonal test.After the fermentation was finished,bacteria powder was made by spraying and dying.Then different promoters were added to make the wettable powder with effective content of 10^10 CFU/g.The wettable powder was used to conduct field control test of rice sheath blight.【Result】The results showed that the best formulation of fermentation medium for spore production of GM-1-1 strain was as follows:wheat bran 0.75%,peanut meal 2.5%and CaCO3 0.05%.The optimum fermentation conditions were as follows:pH 7,temperature 30℃,broth content 60 mL in 250 mL triangular flask,inoculation amount 8%,rotation speed 200 r/min and incubation time 54 h.After optimization,the total number of bacteria and spore production rate infermentation mediumof GM-1-1 strain reached 7.4×10^9 cells/mL and 89.42%respectively.The results of field control test showed that control efficacy of GM-1-1 wettable powder on rice sheath blight could be up to 82.06%.【Conclusion】The optimized medium and fermentation conditions can effectively increase total number of bacteria and spore production rateof GM-1-1 strain,and the culture cost is low and with wide source.The control efficacy of GM-1-1 wettable powder on rice sheath blight is fine.Therefore,GM-1-1 can be used to produce bacterial agents and then be promoted and applied.