Microbial production of 2,3-butanediol by a mutagenized strain of Serratia marcescens H30

The production of 2,3-butanediol (2,3-BD) by Serratia marcescens H30 from sucrose was studied. Medium composition for 2,3-BD production by S. marcescens H30 was optimized in shake flask fermentations using Plackett–Burman design (PB) and response surface methodology (RSM). Results indicated that yeast extract and sodium acetate had significant effects on the 2,3-BD production. And their optimal concentrations were determined by RSM. The optimal medium was used to perform fermentation experiments by S. marcescens H30 in a 3.7 l bioreactor. Several feeding strategies including interim feeding, exponential feeding and constant residual sucrose concentration feeding were compared for improving 2,3-BD production. Ultimately, a suitable control strategy which combined the respiratory quotient (RQ) control with the constant residual sucrose concentration fed-batch was developed. Using this strategy, the maximum 2,3-BD concentration of 139.92 g/l with the diol (AC + BD) productivity of 3.49 g/l h and the yield of 94.67% was obtained.