In this study,pullulan fermentation medium was optimized through response surface methodology. The three main factors that played important roles in pullulan production which identified by Plackett-Burman design,were xylose,( NH)2SO4and K2HPO4. Subsequently,the central composite design and response surface methodology were applied to further investigate the optimum concentration of the main factors. The results indicated that the optimized concentrations of the main factors were: xylose 55g /L,( NH)2SO40.7g...