The alteration of Microcystis aeruginosa biomass and dissolved microcystin-LR concentration following exposure to plant-producing phenols

Plant‐producing phenols could strongly inhibit the growth of toxic cyanobacteria genera, but the ecological consequences of this action are still unknown. In this work, the activity of selected phenols in relation to the strain Microcystis aeruginosa was investigated. We have found that the mechanism of the growth inhibition could involve both the inhibition of the photosynthetic system and the alkaline phosphatase activity. The excretion of a high amount of microcystin‐LR to the environment was observed as a final result of the application of phenols to the cyanobacterial culture. This finding suggests that first of all an algicidal effect of phenols was probably the reason of the cyanobacterial biomass decreasing. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 341–346, 2007.