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Astaxanthin Production by Phaffia Rhodozyma Fermentation of Pineapple Peel Substrate

Pineapple peel as main material was fermented with Phaffia rhodozyma to produce astaxanthin. Using the Box-Behnken design, the effects of sugar content, initial pH and nitrogen content were studied with the yield of astaxanthin as response value, which was evaluated to optimize the fermentation conditions of astaxanthin production. The optimal fermentation conditions have been reached by the study: sugar content was 36.3 g/L, the initial pH was at 5.85 and nitrogen content was 8 g/L. By validation test, the astaxanthin yield under the optimal condition, which was basically corresponded to the model prediction, was 97.11 %.