Effect of light quality on production of extracellular polysaccharides and growth rate of Porphyridium cruentum

Blue light and red light can be used to improve the efficiency of photosynthesis and increase the production of extracellular polysaccharide. Growth and extracellular polysaccharide production by Porphyridium cruentum were measured as a function of light wavelength and intensity. Light quality was a key factor for controlling the growth and polysaccharide production. The growth rate of P. cruentum increased with enhanced of light intensity, however a light level beyond the saturation point inhibited the growth of microalgae. A chromatic spectrum of blue and red light was used to enhance the growth and extracellular polysaccharide production due to the characteristics of the photosynthetic process. Efficient light transfer was the most important parameters in optimizing the mass culture of the photosynthetic organism. (C) 2004 Elsevier B.V. All rights reserved.