1, 3 - Propanediol Production Klebsiella Metabolic Regulation Research

1,3-propanediol is an important chemical raw material, which is a importantintermediate of polyethylene terephthalate PTT is widely used in variety of industries.Microbial fermentation production of1,3-PD is a green method has increasinglybecome a focus for researchers. The main content of this study include mutationbreeding, mutant strains Optimization of Culture Conditions and fermentation power.This study choose the wild-type Klebsiella strains2-1, use the method of physicalmutation, physical complex mutagenesis and combining physical mutagenesis andchemical mutagenesis, selected a high-yield strains Y-37ultimately.The study use single factor experiment and response surface design to optimize thefermentation process. Single factor test could determine the impact of individual factorson the yield of1,3-PD.Using single-factor test and response surface design coulddetermined the optimum fermentation conditions. As a result the optimal conditionswere analyzed as: glycerol49.9g/L,(NH4)2SO45.28g/L, pH7.19, fermentation time84h, fermentation temperature36.1℃. Using the above optimized conditions, modelpredict the production of1,3-PD is19.03g/L. In the actual experiment the production of1,3-PD is18.33g/L, close to model predictions.On the basis of fermentation curve, the mathematical models were proposed todescribe the fermentation process. The parameters of the models were established byusing1stOpt software with experimental data and the models.The modes consist of:Cell growth model:dX/dt=0.78X(1X/5.43)Production formation model:dp/dt=77.8dX/dt+0.007XSubstrate depletion model: dS/dt=13.158(dX/dt)/+1.205(dp/dt)...