Effect of Nutrients and Temperature Conditions on the Production of Microcystins by Microcystis aeruginosa Isolated from a Wild Population

AMÉ, MARÍA VALERIA; WUNDERLIN, D.A

Springer

Lugar: Holanda; Año: 2005 vol. 168 p. 235 - 235

font color="#0000ff" size="1" face="Arial">We report results of a study conducted to evaluate effects of ammonium, iron and temperature on microcystins (MC) and proteins production in cultures of Microcystis aeruginosa isolated from San Roque reservoir (Córdoba - Argentina). Based on a previous field study, we tested two temperatures (20 and 28°C), two iron concentrations (1 µM and 10 µM) and two ammonium-nitrogen conditions (absence and 54 µM) in semi-continuous cultures. Total MC (TMC=MC-LR+MC-RR) and protein production per cyanobacteria cell increased when Fe concentration was enlarged. However, the ratio TMC: protein was almost the same for both iron concentrations. Thus, a high level of iron enhances both protein and MC production in the same proportion. TMC and protein production are significantly lowered in presence of 54µM-N-ammonium. However, the ratio TMC: protein is significantly lower for cultures having ammonium. Therefore, during the present study, could be considered th