Combined effects of temperature, light intensity, and nitrogen concentration on the growth and polysaccharide content of Microcystis aeruginosa in batch culture

摘要

To evaluate the combined effect of various environmental factors on growth and polysaccharide content of Microcystis aeruginosa, the alga was inoculated into media with different nitrogen concentrations (0.26, 2.55, and 25.47 mg L-1) and cultured under combinations of two temperatures (25 and 30 degrees C) and two light intensities (35 and 80 mu mol photons m(-2) s(-1)) for 12 days. Results showed that growth of M. aeruginosa was significantly inhibited under low nitrogen concentrations and the effect of temperature on growth of M. aeruginosa depended on light intensity. High light intensity increased growth of M. aeruginosa. There were significant interactions on growth among any two or three factors (temperature, light, and nitrogen). Temperature had no effect on polysaccharide content, but light intensity and nitrogen concentration independently had significant impact on soluble extracellular polysaccharide, bound polysaccharide, and total polysaccharide content Additionally, a significant interaction on polysaccharide between light intensity and nitrogen concentration occurred. (C) 2011 Elsevier Ltd. All rights reserved.