Effects of two copper compounds on Microcystis aeruginosa cell density, membrane integrity, and microcystin release.
Ecotoxicol Environ Saf
; 120: 428-35, 2015 Oct.
Article
en En
| MEDLINE
| ID: mdl-26141781
ABSTRACT
Microcystin release following Microcystis aeruginosa cell lysis after copper-based algaecide treatment is often cited as a concern leading to restricted use of algaecide in restoration of natural water resources. To examine this concern, bench-scale experiments were conducted to study responses of M. aeruginosa to 8-day copper exposures as copper sulfate and copper-ethanolamine (Cu-EA). M. aeruginosa UTEX 2385 was cultured in BG11 medium to cell density of 10(6)cells/mL with total and extracellular microcystin of 93 and 53µg/L, respectively. Exposures of copper concentration ranged from 40 to 1000µgCu/L. Cell membrane integrity was indicated by erythrosine B. In the end of experiment, total microcystin and cell density in untreated control (313µg/L and 10(7)cells/mL) was 3.3 and 10 times greater than pretreatment value, respectively. Minimum amount of copper required to reduce M. aeruginosa population within 8 days was 160µgCu/L as copper sulfate and 80µgCu/L as Cu-EA, where total and extracellular microcystin concentrations (47 and 44µg/L for copper sulfate; 56 and 44µg/L for Cu-EA) were degraded with degradation rate coefficient 0.1 day(-1) and were less than pretreatment values. Given a copper concentration at 80µgCu/L as Cu-EA, M. aeruginosa cells were intact and less microcystin were released compared to treatments at 160-1000µgCu/L, where lysed cells and relatively greater microcystin release were observed. Based on the laboratory results, a minimum amount of copper required for reducing M. aeruginosa population could decrease total microcystin concentration and not compromise cells and minimize microcystin release.
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Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Compuestos Organometálicos
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Sulfato de Cobre
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Cobre
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Microcystis
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Etanolaminas
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Microcistinas
Idioma:
En
Revista:
Ecotoxicol Environ Saf
Año:
2015
Tipo del documento:
Article