Geobacillus galactosidasius is a common bacterial group in the livestock and poultry waste composting fermentation process,and plays an important role in aerobic composting fermentation.To obtain the optimal liquid fermentation conditions for strain BWTGW1-1 and establish its large-scale production process,a single factor and response surface methodology were used to optimize the composition and fermentation conditions of the liquid fermentation of strain BWTGW1-1.The results showed that the optimal medium composition and conditions for liquid fermentation of strain BWTGW1-1 were as follows:mannitol(2.50 g/L),yeast extract(8 g/L),soy peptone(5 g/L),sodium chloride(1.50％),culture temperature of 60 ℃,pH value 6.00,and liquid inoculum(0.50％).Under these conditions,the OD600nm value of the liquid inoculum of strain BWTGW1-1 reached 1.423 7.On this basis,using a 5 ton liquid fermentation tank system,a large-scale liquid fermentation process for strain BWTGW1-1 was established,and validated through two batches of large-scale production.Nearly 5.50 tons of strain BWTGW1-1 liquid microbial product were obtained,with an effective viable bacterial count of 7.25x108 CFU/mL.The effective viable count in the spray-dried raw powder reached 1.12x1010 CFU/g,with a noticeably low impurity rate(＜0.01％).Conclusively,the optimal pilot production fermentation conditions for strain BWTGW1-1 were as follows:mannitol 2.50 g/L,yeast extract 8 g/L,soy peptone 5 g/L,NaCl 1.50 wt.％,pH 6.00,temperature 60 ℃,fermentation speed 150 r/min for 0～12 h,250 r/min for 12～24 h,ventilation rate 20 m3/h,and fermentation time of 24 h.
关键词
半乳糖地质杆菌/耐高温/液体发酵条件/响应面优化/中试发酵
Key words
Geobacillus galactosidasius/high temperature resistance/liquid fermentation conditions/response surface optimization/pilot fermentation
维普
万方数据