吡咯喹啉醌生产菌的发酵条件优化

对一株产吡咯喹啉醌(PQQ)假单胞杆菌Pseudomonas 0813的发酵条件进行了优化，通过单因素试验确定碳源、氮源及无机盐成分，之后用正交试验法优化各成分配比，考察了发酵温度、初始pH值和转速对该菌产PQQ的影响。结果表明，最优的培养基配方为：酵母粉5g/mL、蛋白胨1g/mL、KH₂PO₄ 0.5g/mL；最适的发酵条件为：发酵温度30℃、初始pH 6.5、发酵转速150r/min。在此条件下，Pseudomonas0813菌株在250mL体系摇瓶发酵中的PQQ产量为448mg/L，在1.5L体系发酵罐扩大培养后的最高产量可达 695.mg/L，这是目前报道未经优化或基因改造菌株的较高产量。

Optimization of fermentation conditions for pyrroloquinoline quinone expression by Pseudomonas 0813

A pyrroloquinoline quinone (PQQ) synthesizing stain Pseudomonas 0813 has been fermented and the fermentation conditions were optimized. Single factor tests were carried out to determine the appropriate carbon source, nitrogen source and inorganic salt. Orthogonal tests were performed to determine the optimum ratios of the components in the fermentation medium. The cultivation temperature, initial pH value and rotation speed were also optimized. The results showed that the optimum medium composition was yeast extract 5g/mL, tryptone 1g/mL, and KH₂PO₄ 0.5g/mL, whilst the optimized fermentation conditions were a fermentation temperature of 30℃, an initial pH value of 6.5 and a rotation speed of 150r/min. Using the above conditions, the yields of PQQ using this strain reached 448mg/L and 695mg/L in a 250mL shaken flask and a 1.5L fermenter, respectively. These are notable yields for wild type strains devoid of mutagenesis and genetic modification.