一株水质净化解淀粉芽孢杆菌 HN 发酵参数的优化

摘要

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/250 mL，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35．6×108 cfu/mL，最高芽孢浓度达到30．4×108 cfu/mL；100 L发酵罐验证试验表明，37℃发酵26 h活菌浓度可达37．0×108 cfu/mL，芽孢浓度为33．6×108 cfu/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 loga-rithmic 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 ×10 8 cfu/mL in 250 mL triangular flask.The valida-tion test in 100 L fermentor result indicated that bacteria number and spore concentration reached 37.0 ×10 cfu/mL and 33.6 ×10 8 cfu/mL ,respectively after fermented at 37 ℃for 26 h.