摘要
对鼠李糖乳杆菌菌株Lactobacillus rhamnosusJCM1553进行紫外诱变,选育得到一株耐高温L-乳酸高产突变菌GX-6。在47℃,分别以葡萄糖和木薯淀粉为底物,研究GX-6菌株发酵生产L-乳酸的情况并考察GX-6菌株的遗传稳定性。结果表明,以葡萄糖为底物时,发酵56h的L-乳酸产量达到117g/L,比出发菌(100g/L)提高17%,糖酸转化率68.8%;以木薯淀粉为底物时,发酵72h的L-乳酸产量达到138g/L,比出发菌株(73g/L)提高77.6%,糖酸转化率达到85.4%。经16次传代培养,GX-6菌株的乳酸发酵性能没有发生显著变化,具有较好的遗传稳定性。
By UV mutagenesis,a high-yield and thermostable L-lactic acid mutant strain-GX-6 was originally obtained from Lactobacillus rhamnosus JCM1553.At 47℃,the maximum L-lactic acid yield of GX-6 in glucose was 117g/L for 56h,which was 17% higher than that of the original strain(100g/L),with a conversation rate of 68.8 %.The maximum L-lactic acid yield was 138g/L for 72h under the same condition in cassava starch,77.6% higher than that of the original strain(73g/L) and the conversation rate reached to 85.4%.After subculture for 16 generations,the L-lactic acid production capacity of GX-6 remains unchanged,indicating that the mutant is stable.
出处
《广西科学》
CAS
2011年第3期269-272,共4页
Guangxi Sciences
基金
国家科技支撑计划项目(2007BAD75B06)
广西科学基金项目(桂科攻0782003-4)
广西科学院基本科研业务费项目(10YJ25SW11)资助
关键词
鼠李糖乳杆菌
紫外诱变
高温L-乳酸发酵
Lactobacillus rhamnosus
UV mutagenesis
L-lactic acid fermentation at high temperature