初始底物浓度及pH对丁酸梭菌T4发酵木糖产氢的影响

Effect of initial substrate concentrations and pH on hydrogen production from xylose with Clostridium butyricum T4

摘要:

本研究采用间歇培养方式对丁酸梭菌 T4发酵木糖进行产氢研究, 考察初始pH和初始底物浓度对其产氢特性的影响。结果表明, 菌株T4 在初始pH 5.0~8.5及初始底物浓度 5~40 g/L时均可以产氢, 其累积产氢量和最大比产氢速率随着pH及底物浓度的增加均呈现先增加后减少的趋势。在pH 6.5和底物浓度20 g/L时, 比产氢速率和累积产氢量达到最大, 分别为4.26 L/L和18.86 mmol-H2/h g-DCW, 而后随着pH或者底物浓度的增加二者均呈现减少的趋势; 在pH 6.5和底物浓度15 g/L时, 得到最大值比产氢量为2.17 mol/mol-木糖。而在不同的pH下, 发酵产生的液态产物主要是乙酸和丁酸, 其中在pH小于6.0时, 有少量的丙酸生成, 而在pH大于6.0时, 则有乙醇生成。

Abstract:

We studied the effect of initial pH and substrate concentrations on the conversion of xylose to hydrogen by Clostridium butyrium T4 at pH 5.0?8.5 and substrate concentrations 5?40 g/L. The cumulative hydrogen volume and the specific hydrogen production rate increased and then decreased with increasing initial pH or substrate concentrations. At initial pH 6.5 and substrate concentration 20 g/L, the cumulative hydrogen production and the specific hydrogen production rate reached the maximum value of 4.26 L/L and 18.86 mmol-H2/h g-DCW (dry cell weight).