title: Microcystins associated with Microcystis dominated blooms in the Southwest wetlands, Western Australia.
abstract: Potentially toxic cyanobacterial blooms are becoming common in the freshwater wetlands on the Swan Coastal Plain, Western Australia. During summer the dominant bloom-causing species belong to the genera Microcystis and Anabaena and to a lesser extent Aphanizomenon and Nodularia. Although toxic cyanobacteria have been recorded in the Swan-Canning and Peel-Harvey estuaries in Western Australia, very little is known about the blooms in the surrounding freshwater lakes. In this study, a total of 32 natural bloom samples representing 13 lakes were analyzed by HPLC for microcystin (MC)-LR, -RR, and -YR. Twenty-eight samples proved to be toxic. The highest total microcystin concentration ranged from 1645 to 8428.6 microg L(-1), and the lowest concentrations were less than 10 microg L(-1) with some below the detection limit (< 0.05 microg L(-1)). MC-LR (100%) was the predominant microcystin, followed by MC-YR (71.4%) and MC-RR (60.7%). The presence of a Nodularia spumigena bloom in the freshwater Lake Yangebup was associated with the detection of nodularins (1664 microg L(-1)). This is the first study to demonstrate the presence of microcystins and nodularins in urban lakes on the Swan Coastal Plain, Western Australia.
authors.affiliation: Department of Environmental Biology, Curtin University of Technology, Perth, Western Australia 6845, Australia. annabeth.kemp@postgrad.curtin.edu.au
authors.forename: Annabeth
authors.initials: A
authors.lastname: Kemp
authors.forename: Jacob
authors.initials: J
authors.lastname: John
mesh_terms: D001427:Bacterial Toxins / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D004784:Environmental Monitoring; D005618:Fresh Water / Q000382:microbiology*; D005843:Geography; D052998:Microcystins; D046931:Microcystis / Q000254:growth & development / Q000302:isolation & purification* / Q000378:metabolism; D046932:Nodularia / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D010456:Peptides, Cyclic / Q000032:analysis* / Q000378:metabolism; D014904:Western Australia
chemical_list: D001427:Bacterial Toxins; D052998:Microcystins; D010456:Peptides, Cyclic; C063998:nodularin; C078588:microcystin