EFFECT OF IRON STRESS ON OXIDATIVE STRESS AND TOXIN PRODUCTION BY FRESHWATER CYANOBACTERIA

Abstract

 Microcystis aeruginosa produces microcystin that is one of the hepatotoxin to human. Recent studies have shown that oxidative stress causes MCs production in the cellular processes. In addition, it has been indicated that iron limitation induces production of reactive oxygen species and associated oxidative stress in cyanobacterial cell. Therefore, this study aimed to elucidate the relationship among iron-stress induced oxidative stress and MCs production. Consequently, MCs content (per cell) increased under the intermediate iron availability (total dissolved iron concentration of 100 nM), where oxidative stress was also determined to be high. Moreover, overall MCs production rate showed the lowest value in the intermediate iron stress (i.e., total dissolved iron concentration of 100 nM), as the overall MCs production is also related to the cellular growth rate.