Acute effects of a prooxidant herbicide on the microalga Chlamydomonas reinhardtii: Screening cytotoxicity and genotoxicity endpoints.

摘要: Since recent evidence has demonstrated that many types of chemicals exhibit oxidative and/or genotoxic potential on living organisms, reactive oxygen species (ROS) formation and DNA damage are currently the best accepted paradigms to assess hazardous biological effects a wide range contaminants. The goal this study was evaluate sensitivity different cytotoxicity genotoxicity responses model microalga Chlamydomonas reinhardtii exposed prooxidant herbicide paraquat. In addition growth endpoint, cell viability, mitochondrial membrane presence were assayed as markers using flow cytometry (FCM). To paraquat C. DNA, several approaches implemented for first time in an ecotoxicological microalgae. Oxidative base analysed by measuring lesion 8-OHdG FCM. fragmentation methods: comet assay, cycle analysis FCM, with particular focus subG1-nuclei. Finally, morphology nuclei monitored through DAPI staining. evaluation these endpoints showed physiological biochemical parameters reacted stress disturbances greater than integrative such rates or viability. experiments revealed concentration-dependent (ROS formation, depolarization membrane), (oxidative damage, strand breakage, alterations nuclear morphology), (subG1-nuclei, decrease 4N population) paraquat-treated cells. Overall, results indicate production ROS caused exposure induces followed single- double-strand breaks alterations, possibly leading apoptosis This is supported observation typical hallmarks apoptosis, depolarization, subG1 cells highest concentrations. our knowledge, provides comprehensive unicellular algal pollutant, well its possible relation other effects. These reinforce need additional studies environmental pollutants ecologically relevant organisms microalgae can provide promising basis characterization pollutant hazards aquatic environment.