title: Ultrasonically induced degradation and detoxification of microcystin-LR (cyanobacterial toxin).
abstract: Cyanobacterial toxins (CBTs), produced by glue-green algae, are one of the most common naturally occurring toxins found in potable waters. The microcystin family of CBTs present in drinking water sources poses a considerable threat to human health. In this study, we have demonstrated that ultrasonic irradiation at 640 kHz leads to rapid degradation of microcystin-LR (MC-LR). Degradation of MC-LR present in the crude cyanobacterial extracts containing cell constituents has been studied with ultrasound under a variety of conditions. The degradation of MC-LR was demonstrated over a concentration range from 0.03 to 3.0 microM. Hydroxyl radical scavenger experiments indicate that hydroxyl radical is responsible for a significant fraction of the observed degradation, but other processes (hydrolysis/ pyrolysis) are also important. Analysis of the protein phosphatase inhibition activity of the reaction products indicates that the products from ultrasonic degradation of MC-LR do not exhibit any measurable biological activity. The results demonstrate that ultrasonic irradiation maybe an effective and practical method for the detoxification of microcystins from drinking water.
authors.affiliation: Department of Chemistry and Biochemistry, Florida International University, University Park, Miami, Florida 33199, USA.
authors.forename: Weihua
authors.initials: W
authors.lastname: Song
authors.forename: Terri
authors.initials: T
authors.lastname: Teshiba
authors.forename: Kathleen
authors.initials: K
authors.lastname: Rein
authors.forename: Kevin E
authors.initials: KE
authors.lastname: O'Shea
mesh_terms: D000458:Cyanobacteria; D017665:Hydroxyl Radical; D008387:Marine Toxins; D052998:Microcystins; D010456:Peptides, Cyclic / Q000737:chemistry*; D014465:Ultrasonics; D018508:Water Purification / Q000379:methods*
chemical_list: D008387:Marine Toxins; D052998:Microcystins; D010456:Peptides, Cyclic; D017665:Hydroxyl Radical; C057862:cyanoginosin LR