嗜鞣管囊酵母木糖发酵乙醇高产突变株选育及其发酵特性

目前能够利用木糖发酵产乙醇的菌株很少且产量较低,对菌株进行诱变选育,可以提高其对木质纤维集的利用率.本试验选择嗜鞣管囊酵母As2.1585为原始菌株,采用15keV的低能氮离子进行注入诱变.随着注量的增加,菌体存活率曲线呈"马鞍型",综合考虑其存活率和正突变率,确定最佳诱变注量为12.5×1014ions/cm2,对诱...

BREEDING AND FERMENTATION CHARACTERIZATION OF Pachysolen Tannophilus MUTANT WITH HIGH ETHANOL PRODUCTIVITY FROM XYLOSE

Currently, few strains can utilize xylose to produce ethanol with very low productivity. By the method of mutation breeding to these strains the rate of lignocellulosic utilization could be improved. In this study,the initial Pachysolen tannophilus As2.1585 was treated by N+ ions implantation of 15keV. The survival curve showed a saddle model. Considering the survival rate and range of positive mutation, the N+ ions implantation of 12.5×1014ions/cm2 for mutation breeding of Pachysolen tannophilus was selected. A Pachysolen tannophilus mutant mut-54, which had perfect genetic stability of producing ethanol was screened out after continuous 7 passages. The mut-54 had a higher xylose consumption rate, biomass accumulation and ability of ethanol-resistant than the parent strain. Compared with the parent strain, the ethanol concentration fermented by the mut-54 for 72h increased by 12.74 %, which was more suitable for producing ethanol from xylose than the parent strain.