一株产2-酮基-D-葡萄糖酸菌的筛选鉴定及其发酵优化

Screening and Identification of 2-Keto-D-gluconic Acid-producing Strain

以(NH4)2SO4为底物氮源,采用平板变色圈法从土壤中分离筛选出一株2-酮基-D-葡萄糖酸生产菌株Serratia sp.FMME043,对其碳源、氮源、无机源和摇瓶类型等产酸条件进行优化,确定以(NH4)2SO4为氮源的摇瓶产酸最佳条件为葡萄糖180g/L,(NH4)2SO42.0g/L,KH2PO41g/L,在初始pH7.0及750mL双刺摇瓶装液量10%、培养温度30℃、摇床转速200r/min条件下发酵48h,2-酮基-D-葡萄糖酸产量达169.5g/L,得率为0.87mol/mol,并在7L发酵罐中进行了验证.

A 2-keto-D-gluconic acid （2-KGA） producing strain Serratia sp. FMME043 was isolated from the soil by the method of flat discolor circle with （NH4）2SO4 as nitrogen source. The optimal conditions, glucose 180 g/L, （NH4）2SO4 2.0 g/L and KH2PO4 1 g/L, were obtained through one-factor experimental design. Furthermore, the highest 2-KGA concentration 169.5 g/L and yield 0.87 mol/mol were achieved under the optimum conditions with initial pH 7.0, liquid volume 75 mL in a 750 mL flask, culture temperature 30 ℃, and shaker rotating speed 200 r/min. These results were also confirmed in a 7 L fermentor.