一株水质净化解淀粉芽孢杆菌HN发酵参数的优化

Optimization of Fermentation Parameters for Bacillus amyloliquefaciens HN with Water Purification

采用单因素试验和正交试验对具有水质净化功能的解淀粉芽孢杆菌HN的培养基成分及培养条件进行了优化,并采用100 L发酵罐对优化发酵技术参数进行了验证试验。结果表明,优化的培养基成分为:蛋白胨2.0 g/L,牛肉膏3.0 g/L,可溶性淀粉7.0 g/L,氯化钠6.0 g/L;培养条件为:培养基的初始pH值为7.0,装液量为100 mL/250mL,接种量为3%,温度为37℃,发酵周期24～30 h;在上述优化培养条件下的生长曲线结果显示,菌株HN在9 h后进入对数生长期,24 h达到稳定期,菌液浓度达35.6×108cfu/mL,最高芽孢浓度达到30.4×108cfu/mL;100 L发酵罐验证试验表明,37℃发酵26 h活菌浓度可达37.0×108cfu/mL,芽孢浓度为33.6×108cfu/mL。

The single factor test and orthogonal-design experiment were applied to screen optimal fermentation technology such as medium composition and fermentation conditions for Bacillus amyloliquefaciens HN with water purification,and the fermentation parameters in fermentor of 100 L was scaled up successfully.The results showed that the strain HN was easy to cultivate in a medium with 2.0 g/L peptone,3.0 g/L beef extract,7.0 g/L soluble starch,6.0 g/L NaCl and the optimum fermentation conditions were initial culture medium pH 7.0,inoculation rate 3%（V/V）,100 mL/250 mL medium volume at 37 ℃ for 24-30 h.Under this condition,strain HN reached logarithmic phase at 9 h,came to stable period after cultured at 37 ℃ for 24 h and the bacteria concentration reached 35.6×108 cfu/mL and the spore concentration was up to 30.4×108 cfu/mL in 250 mL triangular flask.The validation test in 100 L fermentor result indicated that bacteria number and spore concentration reached 37.0×108 cfu/mL and 33.6×108 cfu/mL,respectively after fermented at 37 ℃ for 26 h.