Enhanced production of astaxanthin by the green microalga Chlorella zofingiensis in mixotrophic culture

Mixotrophic culture may be used as an efficient means for enhanced production of light-induced pigments in microalgae. The growth and pigments formation of the green microalga Chlorella zofingiensis cultivated at various glucose and nitrate concentrations in mixotrophic culture were investigated. High glucose and low nitrate concentrations favoured the production of astaxanthin in the algal culture. The highest yield of astaxanthin was 12.5 mg l(-1), which was obtained in the medium containing 30 g l(-1) glucose and 0.55 g l(-1) nitrate. The results indicated that supplementation of glucose and nitrate in the culture medium could be effectively manipulated to enhance astaxanthin production by C. zofingiensis in mixotrophic culture. (C) 2003 Elsevier Ltd. All rights reserved.