Application of Cytotoxicity Assays for Detection of Potentially Harmful Bioactive Compounds Produced by Freshwater Bloom-Forming Algae

Author

Jace Thomas McLaughlin, The University of Western OntarioFollow

Degree

Master of Science

Program

Biology

Supervisor

Dr. Irena Creed

2nd Supervisor

Dr. Charles Trick

Joint Supervisor

Abstract

Detection of harmful bioactive compounds produced by bloom-forming pelagic algae is important to assess the potential risks to communities. We applied two cell-based assays, an erythrocyte lysis assay (ELA) that assesses membrane integrity, and a RTgill-W1 cytotoxicity assay (RCA) that detects changes in cell metabolism, to evaluate the cytotoxic effects of: (1) individual toxins and noxious compounds; and (2) complex mixtures of compounds produced by cyanobacteria and chrysophyte isolates. ELA was insensitive to toxins and noxious compounds except at exceptionally high concentrations (EC₅₀≥10⁶ nM). RCA was sensitive to noxious compounds only, at concentrations greater than reported environmental averages (EC₅₀≥10³ nM). Cultured isolates produced bioactive compounds that had recognizable, dose dependent, toxic effects. Toxicity of these bioactive compounds depended on the taxa (cyanobacteria, not chrysophytes), growth stage (stationary phase more toxic than exponential phase), location (intracellular more toxic than extracellular), and iron status (iron-replete cells more toxic that iron-deplete cells).

Recommended Citation

McLaughlin, Jace Thomas, "Application of Cytotoxicity Assays for Detection of Potentially Harmful Bioactive Compounds Produced by Freshwater Bloom-Forming Algae" (2012). Electronic Thesis and Dissertation Repository. 1095.
https://ir.lib.uwo.ca/etd/1095