酶水解液的丁醇发酵条件优化研究

［目的］研究抗坏血酸（AsA）对镉胁迫下小麦种子萌发及幼苗生长的保护效应。［方法］以扬麦15、扬麦16和扬麦17为试材，通过测定种子发芽率和幼苗的生长生理指标研究了外源AsA对镉胁迫下小麦种子萌发和幼苗生长的影响。［结果］在单因素试验中，浓度大于0.05mmol/L的AsA对小麦幼苗主根生长有抑制作用；小麦种子萌发和幼苗生长受到的抑制作用随着镉浓度增大而增强，小麦根系SOD活性没有明显变化。AsA浓度不变时，小麦根长生长受到的抑制作用随着镉浓度的增大而增强；镉浓度不变时，0.05mmol/LAsA处理的小麦的抑制百分比低于其他浓度。在镉胁迫下加入AsA后，小麦根系SOD活性明显提高。0.05mmol/LAsA对0.05mmol/L镉胁迫下小麦的POD活性提高最多。［结论］低浓度AsA能缓解镉胁迫对小麦种子萌发和幼苗生长的抑制作用，高浓度AsA的作用不明显。

Optimization of Butanol Production from Corn Straw Hydrolysate by Clostridium acetobutylicum

With enzymatic hydrolysis as the fermentation substrate,Plackett-Burman design method was adopted to screen fifteen influencing factors for butanol production by Clostridium acetobutylicum CICC 8008.The results showed the key factor was CaCO3.Based on these results,response surface method was used for further study on the effects of CaCO3,temperature and reaction time in order to find out the optimum concentration levels.The concentration of butanol could reach 6.20 g/L,compared to initial 5.15 g/L,and the ...