title: Toxin extraction from an Anabaenopsis milleri--dominated bloom.
abstract: This paper reports the presence of microcystin type toxins in extracts of a natural bloom of cyanobacteria composed predominantly of Anabaenopsis milleri Woronichin. The toxins have been extracted, purified and compared to microcystin-LR. The LD50 of A. milleri bloom material was 600-1500 mg lyophilized cells/kg body weight. Symptoms and pathological signs of poisoning in mice were characteristic of cyanobacterial hepatotoxins, with enlarged darkened livers with weights of 8-10% of the total body weight. Thin-layer chromatography of the extract resulted in one toxic band, which was separated from pigments and 280-nm absorbing compounds. The toxic fraction was further separated using reversed phase high performance liquid chromatography and one toxic band was recovered. This fraction yielded a single, toxic peak with a retention time of 11.3 min after high performance liquid chromatography. The absorption spectrum of the purified toxin had a maximum at 238-240 nm and was characteristic of cyanobacterial hepatotoxic peptides. Comparison of the chromatographic behaviour of the purified toxin with microcystin-LR on reversed phase and on internal surface reversed phase, high performance liquid chromatography indicated that an A. milleri bloom material toxin was a microcystin type toxin and it is highly likely that the purified toxin is microcystin-LR.
authors.affiliation: Department of Botany, University of Thessaloniki, Greece.
authors.forename: T
authors.initials: T
authors.lastname: Lanaras
authors.forename: C M
authors.initials: CM
authors.lastname: Cook
mesh_terms: D000818:Animals; D000458:Cyanobacteria / Q000737:chemistry*; D005068:Eutrophication; D007928:Lethal Dose 50; D008387:Marine Toxins; D051379:Mice; D052998:Microcystins; D010456:Peptides, Cyclic / Q000737:chemistry / Q000302:isolation & purification* / Q000633:toxicity
chemical_list: D008387:Marine Toxins; D052998:Microcystins; D010456:Peptides, Cyclic; C057862:cyanoginosin LR