Journal
HARMFUL ALGAE
Volume 10, Issue 6, Pages 668-675Publisher
ELSEVIER
DOI: 10.1016/j.hal.2011.05.002
Keywords
Aphanizomenon ovalisporum; Cylindrospermopsin; Invasive; Light intensity; Release; Temperature
Categories
Funding
- FPU
- Ministerio de Ciencia e Innovacion (MICINN, Spain)
- German Ministry of Education and Research and Kompetenzzetrum Wasser Berlin
- Veolia Water and Berliner Wasserbetriebe
Ask authors/readers for more resources
The growth rates, production and release of the potent cytotoxin cylindrospermopsin (CYN) were studied in batch and semi-continuous cultures of Aphanizomenon ovalisporum (Cyanobacteria; Nostocaceae) strains UAM 289 and UAM 290 from Spain, over a gradient of temperatures (10-40 degrees C) and irradiances (15-340 mu E m(-2) s(-1)). This species grew in temperatures ranging from 15 degrees C to 35 degrees C as well as under all irradiances assayed. The growth rates ranged from 0.08 d(-1) to 0.35 d(-1), and the maximum growth was recorded above 30 degrees C and at 60 mu E m(-2) s(-1). CYN was produced under all conditions where net growth occurred. Total CYN reached up to 6.4 mu g mg(-1) dry weight, 2.4 mu g mm(-3) biovolume, 190.6 fg cell(-1) and 0.5 mu g mu g(-1) chlorophyll a. Although CYN concentrations varied only 1.9-fold within the 15-30 degrees C range, a drastic 25-fold decrease was observed at 35 degrees C. The irradiance induced up to 4-fold variations, with maximum total CYN measured at 60 mu E m(-2) s(-1). An elevated extracellular CYN share ranging from 20% to 35% was observed during the exponential growl:h phase in most experiments, with extreme temperatures (15 and 35 degrees C) being related to the highest release (63% and 58%, respectively) and without remarkable influence of irradiance. Growth did not have a direct influence on either CYN production or release throughout the entire range of experimental conditions. Our study demonstrates a strong and stable production and release of CYN by A. ovalisporum along field-realistic gradients of temperature and light, thus becoming a predictive tool useful for the management of water bodies potentially affected by this ecologically plastic cyanobacterium. (C) 2011 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available