摘要
在50 L发酵罐水平对影响毕赤酵母表面展示米黑根毛霉脂肪酶(Rhizomucor miehei lipase,RML)发酵因素进行了研究。最适初始菌体密度(OD600)约为250,最佳诱导pH为6.0;降低诱导温度能有效提高单位甲醇转化率,诱导温度为20℃和25℃时的转化率分别是30℃的1.56倍和1.32倍。在以上最适条件下单位干菌体展示酶活及生产强度分别达275.0 U/g和462.5 U/(L.h),比优化前提高54.5%。研究发现,山梨醇和甲醇混合补料有效地提高了诱导前期(t=12h)的产酶效率,当山梨醇和甲醇混合比例为1∶4及1∶5是以甲醇为单一碳源时酶活力的1.7倍。
Several key factors which affect the production of Rhizomucor miehei lipase （RML） displayed on cell surface of Pichia pastoris were studied by 50 L scale fermentation. Results indicated that the optimum initial induction cell density （ OD6oo） was around 250 ; the optimum pH during induction phase was 6.0; reducing temperature during induction phase resulted in increase of specific productivity by 1.56 and 1.32 folds at 20℃and 25℃ respectively, compared to that of 30℃. Under the above optimum conditions, the RML activity and productivity reached 275.0 U/ g and 462.5 U/（L· h）, increased by 54.5% compared to that of initial conditions. Methanol/Sorbitol co -feeding strategy was also studied. By implementing this strategy and setting the sorbitol and methanol mix rate at 1：4 and 1： 5, the RML productivity at 12h was 1.7 times of that by sole carbon resource.
出处
《食品与发酵工业》
CAS
CSCD
北大核心
2011年第9期54-58,共5页
Food and Fermentation Industries
基金
大宗工业酶生产过程的共性关键技术与应用(2010A010500003)
关键词
毕赤酵母
米黑根毛霉脂肪酶
发酵优化
流加策略
Pichia pastoris, Rhizomucor miehei lipase, fermentation optimization, feeding strategy
