分阶段pH调控提高2-酮基-L-古龙酸生产  

Enhancement of 2-keto-L-gulonic acid production using three-stage pH control strategy

作　　者：张静[1,2] 周景文[1,2] 刘立明[1,2] 刘杰[3] 陈克杰[1,2] 堵国成[2] 陈坚[1,2] 

机构地区：[1]江南大学工业生物技术教育部重点实验室,无锡214122 [2]江南大学生物工程学院生物系统与生物加工工程研究室,无锡214122 [3]江苏江山制药有限公司,靖江214500

出　　处：《生物工程学报》2010年第9期1263-1268,共6页Chinese Journal of Biotechnology

基　　金：国家杰出青年基金(No.20625619);国家重点基础研究发展计划(973计划)(No.2007CB714306);江苏高等学校优秀科技创新团队项目;国家高技术研究发展计划(863计划)(No.2006AA020303);"十一五"国家科技支撑计划(No.2007BAI46B02)资助~~

摘　　要：为了提高酮古龙酸菌Ketogulonicigenium vulgare和巨大芽胞杆菌Bacillus megaterium生产2-酮基-L-古龙酸(2-KLG)的生产效率,分析了pH对K.vulgare和B.megaterium生长和产酸的影响,发现K.vulgare和B.megaterium的最适生长pH值分别为6.0和8.0,但是K.vulgare的糖酸转化活力在pH7.0时达到最大值,因此提出了三阶段pH控制策略(第一阶段:0～8h,pH8.0;第二阶段:8～20h,pH6.0;第三阶段:20h至发酵结束,pH7.0)以促进K.vulgare生长和2-KLG生产。结果表明,三阶段pH控制策略的实施进一步提高了2-KLG的产量(77.3g/L)、生产强度(1.38g/(L·h))和L-山梨糖消耗速率(1.42g/(L·h)),分别比恒定pH7.0时提高了9.7%、33.2%和25.7%。The aim of this study was to improve the 2-keto-L-gulonic acid （2-KLG） production efficiency by Ketogulonicigenium vulgare and Bacillus megaterium by using multi-stage pH control strategy. The effect of pH on the cell growths and 2-KLG production showed that the optimum pH for K. vulgare and B. megaterium cell growth were 6.0 and 8.0,respectively,while the optimum pH for 2-KLG production was 7.0. Based on the above results,we developed a three-stage pH control strategy：the pH was kept at 8.0 during the first 8 h,then decreased to 6.0 for the following 12 h,and maintained at 7.0 to the end of fermentation. With this strategy,the titer,productivity of 2-KLG and L-sorbose consumption rate were achieved at 77.3 g/L,1.38 g/（L·h） and 1.42 g/（L·h）,respectively,which were 9.7%,33.2% and 25.7% higher than the corresponding values of the single pH （pH 7.0） control model.

关 键 词：pH调控策略 酮古龙酸菌 巨大芽胞杆菌 

分 类 号：TQ921[轻工技术与工程—发酵工程]