Ultrasonically induced degradation and detoxification of microcystin-LR (cyanobacterial toxin)

Environ Sci Technol. 2005 Aug 15;39(16):6300-5. doi: 10.1021/es048350z.

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.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Cyanobacteria
  • Hydroxyl Radical
  • Marine Toxins
  • Microcystins
  • Peptides, Cyclic / chemistry*
  • Ultrasonics*
  • Water Purification / methods*

Substances

  • Marine Toxins
  • Microcystins
  • Peptides, Cyclic
  • Hydroxyl Radical
  • cyanoginosin LR