阿舒假囊酵母摇瓶分批补料发酵产核黄素的研究

Study on the shake-flask fed-batch fermentation of riboflavin by Eremothecium ashbyii

利用摇瓶分批补料培养模式考察了补料基质对核黄素合成的影响。首先考察了葡萄糖补加浓度对阿舒假囊酵母菌体生长和核黄素合成的影响,结果表明,葡萄糖的补加对阿舒假囊酵母的菌体生长具有促进作用,但是当葡萄糖的补加浓度超过0·5g/100mL发酵液时,会对核黄素的合成产生严重的阻遏或抑制效应。在此基础上,考察了补加不同碳源对核黄素发酵的影响,结果显示,补加1·0g/100mL发酵液的蔗糖或麦芽糖虽然均利于菌体生长,但同样会对核黄素的合成具有负作用。最后考察氮源的补加对阿舒假囊酵母发酵的影响,结果表明,补加酵母膏和玉米浆能显著促进菌体的生长,且二者最终的核黄素合成量分别为1582·1mg/L和1816·77mg/L,均明显高于不补加任何氮源实验方案下的1135·48mg/L。

The components of feeding medium were investigated by the shake-flask fed-batch cultivation of Eremothecium ashbyii.Firstly,the effects of various concentrations of glucose feeding on cell growth and riboflavin biosynthesis were performed.The results showed that glucose feeding could accelerate the cell growth,but the concentration of glucose feeding above 0.5g/100mL would cause lower production of riboflavin.Secondly,the study of various carbon sources on the fermentation of E.ashbyii revealed that,1.0g/100mL of sucrose or maltose had a positive effect on cell growth,and had a negative influence on riboflavin biosynthesis.Finally,the effects of nitrogen sources on the cell growth and riboflavin biosynthesis by E.ashbyii were conducted.The results showed that yeast extract and corn steep liquor could not only stimulate the cell growth,but also had a positive effect on riboflavin biosynthesis.The final riboflavin production under yeast extract or corn steep liquor feeding was 1582.1mg/L and 1816.77mg/L,respectively,which were significantly higher than that obtained without nitrogen feeding（1135.48mg/L）.