Abstract: Phaffia rhodozyma is a good strain for astaxanthin production. Single factor experiment used in this papers identified glucose the best carbon for the medium,and (NH4)2SO4 is the best nitrogen. By orthogonal experimental medium for determining the optimal nitrogen source: (NH4)2SO4 1.5 g / L, carbon: glucose 30 g / L, C / N (carbon and nitrogen ratio): 20, yeast extract: 2 g / L.According to biomass and residual sugar in the medium of yeast in the process of the growth of Phaffia rhodozyma, we know the relationship between the utilization of glucose and the fermentation time, 22-49 hours, cells in a geometric Series growth and entered a period of a few. At this point yeast decomposition of glucose metabolism have a lot of organic acids, the PH value dropped drastically. 53 hours later, the cell concentration has been relatively stable, and yeast into a stable period. At this point glucose utilization has been high, to continue to yeast reproduction, the need to include more nutrients.UV-induced methods used to improve the astaxanthin production.
Keywords：Phafia rhodozyma；astaxanthin；mutat ion breeding
