Optimization of Culture Conditions for Production of Astaxanthin by Phaffia rhodozyma

The effect of medium components (carbon and nitrogen sources) and environmental factors (initial pH, temperature, and working volume) on biomass and astaxanthin production in Phaffia rhodozyma was investigated. The most suitable carbon, nitrogen, working volume, temperature, and initial pH for astaxanthin production were sucrose, yeast extract, 30ml/500ml, 20°C, and pH 7.0, respectively. Subsequently, the optimum incubation conditions (sucrose 40 g/l, mixed nitrogen containing yeast extract and peptone 8g/l, working volume 30 ml/500ml, and initial pH 9.0) were determined with the orthogonal matrix method. After 72h fermentation under the optimal incubation conditions, the maximum yield of astaxanthin was 7.83 g /l (0.702 mg/g dry cell weight), which were 1.6 fold (0.66 fold) higher than that with a basal medium.