Abstract: The most rational mediun composition for Aureobasidiun pullulans stain A45 was determined by orthogomal test(g/L): glucose 50, yeast ointement 0. 3, (NH4)2SO4 0. 3, K2HPO42.0, MgSO4·5H2O 0. 2. and the best fermenation condition was determined. The result of fermention was as follows(g/L): pullulan 34. 6, biomass 16. 7, residual sugar 8. 8. The kinetic curves of fermention process for strain A45 were made.

Key words: pullulan Biomass. Fermentation