Effect of light and temperature on new cyanobacteria producers for geosmin and 2-methylisoborneol

This study evaluates the effect of light intensity and temperature on the taste and odour compounds of two cyanobacteria species isolated as producers of taste and odour compounds, Phormidium retzii, which produced geosmin and Microcoleus vaginatus, which produced 2-methylisoborneol (2-MIB), both being recorded for the first time as producers of these compounds. The results revealed no relationship between the light intensity and temperature for geosmin/2-MIB production under three different levels of the light intensity (17, 33 and 50 mu mol photons m(-2) s(-1)) and temperature (10, 25 and 33 A degrees C). Higher concentrations of total geosmin (96.6 ng L-1) and 2-MIB (135.8 ng L-1) were observed at 17 mu mol photons m(-2) s(-1) and 25 A degrees C. Geosmin and 2-MIB were retained intracellularly during the lag phase and the highest amount of intracellular geosmin and 2-MIB occurred in the late exponential phase, whereas the extracellular geosmin and 2-MIB were released during the stationary and death phase.