【摘要】 研究了亚硝基胍 (NTG)的诱变剂量、处理时间以及氯化钠浓度对野生型荧光假单胞菌M 18存活率的影响 ,NTG的诱变剂量 2 5～ 2 0 0mg/L ,处理时间 10～ 30min范围内 ,随着诱变剂剂量增加和时间的延长 ,M 18的存活率不断下降。NTG的作用剂量 2 5mg/L ,处理时间 10min时 ,细菌存活率为 5 5 %左右。利用细菌存活率为 5 5 %时的诱变条件 ,经生物测定 ,初筛获得 2 0株抑菌效果明显的诱变株。经摇瓶发酵复筛 ,从这 2 0株诱变株中 ,获得PCA高产诱变株M 18N0 7。并对此菌株发酵条件进行调整 ,较理想的培养条件为 :蛋白胨 18g/L ,葡萄糖 16 g/L ,氯化钠 1g/L ,硝酸钾10 g/L。小瓶培养时间 17h ,大瓶 5 %接种量 ,2 8℃培养 5 4h。更多还原

【Abstract】 The offects of the concentration and working time of NTG ,as well as the concentration of NaCl on the living rate of Pseudomonas fluorescens sp. M18 was investigated. When the concentration of NTG was 25～200mg/L and working time was 10～30min, the living rate of M18 was decreased with addition of the concentration and time. If the concentration of NTG was 25mg/L and the working time was 10min,the living rate of M18 was 55%.Under these conditions , 20 potential stains with significant biocontrol effects were obtained,especially the strain Pseudomonas fluorescens sp. M18N07 from above potential strains with high yield of PCA. The fermentation conditions for the mutant strain was then optimized. The optimal medium for PCA production was:protein 18g/L,glucose 16g/L,NaCl 1g/L,KNO 3 10g/L, 50mL(250mL) flask for 17 hours,5%(v/v) inoculation, 150mL(500mL) flask for 54 hours,28℃.更多还原