Algal and cyanobacterial blooms incur current treatment challenges such as high operational cost, disinfectant by-product formation, and the requirement to separate oxidants from solution after the oxidation. Advanced oxidation methods, such as cold plasma activated bubbles (CPAB), have the potential to overcome the current challenges . CPAB are bubbles containing partially or fully ionised gas that utilise the ambient condition of gas and an electric discharge to produce and deliver highly reactive oxygen and nitrogen species, such as ozone, hydrogen peroxide, hydroxyl, superoxide, and nitric oxide radicals. This project will examine methods to optimise the application of CPAB across a range of algal and cyanobacterial species to increase its technology readiness level.

PhD Thesis underway by Angelina.

The genus Microcystis is responsible for many ‘nuisance’ and toxic algal blooms that threaten various fresh water bodies in Australia. Of particular importance is the taxa Microcystis aeruginosa which is highly prevalent and contains a deep pangenome, leading to substantial genomic variability between strains. It has been established that certain cyanobacteria, including hepatotoxic Microcystis species, annually transition between planktonic and benthic forms. Benthic-planktonic coupling has been associated with an increase in the abundance of Microcystis during spring and summer, often resulting in dense surface blooms, followed by the sedimentation of colonies to the benthos during the cooler months. In order to improve industry predictions of the risk, timing and severity of toxic Microcystis blooms, this project aims to investigate the biological mechanisms and environmental triggers that cause bloom development. Through a range of classical isolation techniques and various ‘-omic’ studies this project will study the recruitment of benthic dwelling Microcystis species to surface waters.

PhD Thesis underway by Caitlin Romanis.

Cyanobacterial blooms are a concern for water utilities due to the potential production of cyanotoxins and taste and odours. Current detection methods are slow and may not capture changes in bloom density which can prevent utilities in rapidly adjusting their treatment process. This project investigated using in situ fluorometers as a tool for real-time cyanobacteria monitoring an treatment adjustment.

PhD Thesis completed by Florence Choo in 2019.

This project investigated Metabolomics-based applications (LC-MS and GC-MS) to advance cyanobacterial toxin detection and analysis in water to:
• Understand the biochemical triggers for cyanobacterial blooms.
• Identification of any new potential toxins produced from blooms.
• Assess the application of metabolomics  for the rapid detection of cyanobacterial toxins and identification of unknown toxins.
• Asses the cost effectiveness and time efficient technique.
• Characterise the biomolecules present in bloom as toxins are produced.

Thesis underway.

Detection of Algal and Cyanobacterial blooms have increased in lakes, rivers and reservoirs over the last two decades. This hampers drinking water treatment processes due to the high cell numbers and the release of algal organic matter that comprises toxins and taste and odour compounds. This project examined the in-depth potential of in situ fluorometers to improve early warning of bloom development via the analysis of fluorescent cell pigments to give an estimate of cell biovolume.

PhD Thesis completed by Sara Imran Khan in March 2019.

Anabaena circinalis, is a commonly occurring cyanobacterial species in Australian source waters. Its presence poses a number of health and aesthetic issues for drinking water quality due to its production of secondary metabolites. This project isolated and characterised a novel toxic fraction from the Anabaena culture.

Honours Thesis completed by Stefania Sotora in November 2012.

This project investigated the effect of environmental parameters on the regulation of cylindrospermopsin biosynthesis in cyanobacteria inhabiting Australian drinking water supplies.

Honours Thesis completed by Melissa Rapadas in November 2012.

Following the discovery of a species of cyanobacteria displaying novel toxicity, Limnothrix as a cause for concern, this project identified the toxin and developed techniques to detect and isolate it.

PhD Thesis completed by Paul Michael Whan in December 2015.

This project increased understanding of how cyanobacteria adapt and function in today’s environment. It provided insight to the key factors that contribute to growth of Microcystis and Anabaena in relation to physical conditions of the reservoir and reduced as well as predicted the occurrence and toxicity of blooms by understanding toxin regulation.

PhD Thesis completed by Anna Chi Ying Yeung in August 2016.

This project established a bioassay using mouse embryonic stem cells to assess the effects of the cyanobacterial toxin, cylindrospermopsin, on early embryonic development. Using embryonic stem cells cultured in vitro as a model for embryos in vivo, the project will analysed cytotoxicity of cylindrospermopsin, its effects on cell morphology, and on gene expression.