抗植物病原真菌海洋细菌L_1-9菌株的发酵条件优化

目的]优化海洋细菌L1-9菌株的最佳发酵条件。方法]采用均匀设计,测定海洋细菌L1-9菌株的最适培养基;通过正交试验设计,确定其发酵的最适温度、pH值、摇床转速,明确其最佳发酵条件。结果]海洋细菌L1-9菌株的适宜发酵培养基组分为:豆饼粉1.00%,玉米粉1.50%,麦麸1.00%,大米粉0.50%,KH2PO40.05%。正交试验表明,在装液量为50 ml(250 ml三角瓶),接种量5.0%时,最佳发酵条件为:温度23℃,pH值8.0,转速190 r/min。通过平板菌落计数法测得菌体数最多可达1.035×1010个/ml;通过比浊法测得最大OD值量为0.817。在此基础上对接种量和发酵时间的试验结果表明:接种量5.0%,发酵时间84 h时,菌体生长最理想。结论]该研究为海洋细菌L1-9菌株在植物病害的生物防治上的应用提供理论依据。

Optimization of Fermentation Conditions of Anitifungal Marine Bacteria L1-9

Objective] The research aimed to optimize the fermentation conditions of marine bacteria L1-9.Method] The optimum medium of marine bacteria L1-9 was discussed by using uniform design.The optimum temperature,pH value,rotation speed of the fermentation were confirmed by orthogonal experimental design to definitude the optimum fermentation conditions.Result] The suitable component of the fermentation medium for marine bacteria L19 were as follows: bean cake powder 1.00%,corn powder 1.50%,wheat bran 1.00%,rice flour 0.50% and KH2PO4 0.05%.The orthogonal experiment showed that when the liquid volume in 250 ml triangular flask was 50 ml and the inoculation amount was 5%,the optimum fermentation conditions were as follows: temperature of 23 ℃,pH value of 8.0 and the rotation speed of 190 r/min.By the counting method of plate culture,it was determined that the number of bacteria could reach 1.035×1010/ml.By turbidimetric method,the optimum OD was determined as 0.817.On this basis,the test on the inoculation amount and fermentation time showed that the mycelial growth was the most ideal when the inoculation amount was 5.0% and fermentation time was 84 h.Conclusion] This research provided the theoretical basis for applying marine bacteria in the biological control of plant diseases.