毛竹枯梢病拮抗细菌巨大芽孢杆菌6-59菌株的产芽孢条件优化

Optimization of spore formation conditions for antagonistic strain 6-59 of Bacillus megaterium against Ceratosphaeria phyllostachydis

为了提高芽孢的形成率,采用单因素和正交试验设计,通过摇瓶培养对毛竹枯梢病拮抗细菌巨大芽孢杆菌6-59菌株芽孢形成的发酵培养基和培养条件进行优化。结果表明:优化后的培养基配方为:玉米粉1.0%、大豆蛋白胨1.0%、CaCl2·2H2O0.1%、MnSO4·H2O0.05%;适宜培养条件是:种龄20h、接种量8%、培养基初始pH为6.0、装液量30mL/250mL、培养温度30℃、摇床转速200r/min。在此优化条件下,6-59菌株发酵液中的芽孢数量为2×109个/mL,芽孢形成率达96.4%。

In order to improve the formation rate and the quantity of the spore, the medial components and cultural conditions of antagonistic strain 6-59 of Bacillus megaterium against Ceratosphaeria phillostachydis were optimized by single factor and orthogonal tests in shake-flask fermentation method. The results showed that the optimal medial components were composed of 1.0% corn meal, 1.0% soybean tryptone, 0.1% CaC12·2H2O, 0.05% MnSO4·H2O. The optimal culture conditions were at temperature 30℃ with initial pH 6.0 and incubation time 20 h, inoculum volume 80 mL/L, medium volume 30 mL in 250 mL flask and rotation speed 200 r/min. Under this optimum conditions, the spore biomass achieves 2×10^9cfu/mL, formation rate achieves 96.4%.