【摘要】 选育生产乳果糖的高产菌株,为生物法(酶法)合成乳果糖提供技术保障。以乳酸克鲁维酵母变种(JN-187)为出发菌,经紫外线诱变选育出水解活性最高的JU74-09突变菌株;然后以JU74-09菌株为出发菌,经亚硝基胍(NTG)诱变选育出转糖基活性最高的JN91-08突变菌株;该菌株经7次传代实验,显示出良好的遗传稳定性。说明紫外线诱变与亚硝基胍(NTG)复合诱变是一种行之有效的用于生产乳果糖菌株选育的诱变方法。更多还原

【Abstract】 High-yield strains for production of lactulose were bred by compound mutation, with a view of providing technical support for the biological(enzymatic) synthesis of lactulose. By using Kluyveromyceslactis(JN-187) as the original strain, UV mutagenesis was performed to breed Mutant Strain JU74-09 with the highest hydrolysis activity; then, with Mutant Strain JU74-09 as the original strain, nitrosoguanidine(NTG) mutagenesis was performed to breed Mutant Strain JN91-08 with the highest transglycosylation activity. The results of 7 passage experiments showed that Mutant Strain JN91-08 had good genetic stability. All these proved that UV mutagenesis combined with nitrosoguanidine(NTG) mutagenesis is an effective mutation method of breeding strains for production of lactulose.更多还原