一株2-酮基-D-葡萄糖酸(2KGA)产生菌的发酵研究

Study on fermentation conditions of 2-keto-D-gluconic acid by P. putida KD-1

分离到一株能产生2-酮基-D-葡萄糖酸(2KGA)的菌株,经过16SrDNA测序,结果与GenBank中的标准株序列进行同源性比较,鉴定为恶臭假单胞菌Pseudomonas putida,本实验室命名为P.putida KD-1。本文研究了培养基组成中不同碳源、氮源、初始玉米浆浓度、补加葡萄糖浓度、初始pH和发酵控制pH对P.putida KD-1发酵生产2KGA产量的影响。检测2KGA采用两种方法,碘量法和高效液相色谱法。实验结果显示,以6%的葡萄糖、1%玉米浆为初始浓度,补加5%葡萄糖,初始pH6.7,发酵维持pH5.5,200rpm,30℃恒温培养96h,2KGA产量可以达到55g/L。表明该菌的发酵过程具有一定优化空间,可作为日后发酵产2KGA的新菌种。

A strain capable of producing 2 -keto- D- gluconic acid （2KGA） was isolated. The phylogenetic analysis of the strain was based on 16SrDNA. Sequencing results were compared with standard strain sequences in GenBank for homology, it identified that this strain was Pseudomonas putida, named as P. putida KD - 1. The effects of different medium composition including carbon, nitrogen, and initial concentration of corn syrup, additional glucose concentra- tion, initial pH and fermentation control pH on 2KGA production from P. putida KD - 1 were studied. Two methods to detected 2KGA, iodimetry and HPLC. The optimal fermentation conditions were determined： glucose 6%, corn steep liquor 1%, flow plus glucose 5%, initial pH6.7, fermentation pHS. 5, 200rpm, 30 ~C incubated, 96h. Under the above conditions, 2KGA production was up to 55g / L. The results showed that the fermentation process of P. putida KD - 1 can be optimized and the bacteria can be used in the future fermentation of 2KGA.