产腺苷甲硫氨酸酿酒酵母补料分批培养工艺的优化  

Optimization of the Fed-Batch Fermentation Process for S-Adenosyl-L-Methionine Production with Saccharomyces Cerevisiae

作　　者：王志来[1] 郭建[1] 胥加龙 周长林[1] 

机构地区：[1]中国药科大学生命科学与技术学院,江苏南京210009

出　　处：《药物生物技术》2017年第2期106-109,共4页Pharmaceutical Biotechnology

基　　金：江苏省自然科学基金(No.SBK200921231)

摘　　要：对酿酒酵母工程菌Saccharomyces cerevisiae mls1△acs2-Met K在20 L发酵罐中合成腺苷甲硫氨酸(S-adenosyl-L-methionine,SAM)的补料分批培养工艺进行优化,增加糖蜜的流加时间,提高溶解氧水平;在此基础上,测定发酵过程中前体甲硫氨酸的消耗曲线,在发酵后期流加前体甲硫氨酸以提高SAM产量。结果表明,在32~72 h流加糖蜜发酵,最终SAM产量和生物量分别达到6.16 g/L和20.83 g/L。将溶解氧水平提高至30%,发酵136 h,最终SAM产量和生物量分别达到11.40 g/L和25.24 g/L。在此基础上,从96 h开始流加甲硫氨酸至发酵结束,最终SAM产量和生物量分别达到15.23 g/L和28.81 g/L。与未优化的工艺相比,SAM产量提高了147.24%。通过流加糖蜜、甲硫氨酸,提高溶解氧,可以有效提高酿酒酵母在20 L发酵罐中的SAM产量和生物量;该工艺在工业化生产中具有潜在的应用价值。S-adenosyl-L-methionine （SAM） is a kind of very important metabolic product with various physiological activities. Thisstudy aimed to optimize the fed-batch fermentation process in 20-L fermenter, and to improve the SAM production with the engineeredSaccharomyces cerevisiae, in order to satisfy the industrial and medical demand of SAM. In this study, the fed-batch fermentation ofthe engineered Saccharomyces cerevisiae was conducted in 20-L fermenter. The strategies of molasses feeding, dissolved oxygen regula-tion and methionine （Met） feeding were optimized to enhance the SAM accumulation in 20-L fermenter. Meanwhile, the concentra-tions of dry cell weight, reducing sugar and SAM were determined during the fermentation process. The obtained data revealed that,after molasses feeding from 32 h to 72 h,the final SAM production and dry cell wet （DCW） reached 6.16 g/L and 20.83 g/L at136 h in 20-L fermenter. On this basis,after improving the dissolved oxygen to 30% ,the final SAM production and DCW in the fer-mentation broth reached 11.40 g/L and 25.24 g/L after 136 h fermentation. Next, the Met concentration during the fermentationprocess in fermentation broth was determined by high-performance liquid chromatography （ HPLC ） method. The Met consumptioncurve in 136 h fermentation process revealed that the Met concentration in the fermentation broth was lower than 0.3 g/L after 96 h.Then the Met feeding strategy was operated in the fed-batch fermentation. Subsequently, with the molasses feeding, 30% dissolvedoxygen and Met feeding,the SAM production and DCW reached 15.23 g/L and 28.81 g/L after 136 h fermentation. Above all,theSAM production under optimized fermentation condition in 20-L fermenter was improved by 147.24%, compared wtih the initialfermentation condition. The SAM production and DCW were obviously improved after molasses feeding, dissolved oxygen regulationand Met feeding, and finally reached 15.23 g/L and 28.81 g/L, which might have potential to satisfy the industrial scale productionof S

关 键 词：腺苷甲硫氨酸 酿酒酵母 补料分批培养 工艺优化 糖蜜 溶解氧 甲硫氨酸 

分 类 号：TQ460.6[化学工程—制药化工]