Open AccessThis article is
- freely available
Bioactivity of Benthic and Picoplanktonic Estuarine Cyanobacteria on Growth of Photoautotrophs: Inhibition versus Stimulation
CIIMAR/CIMAR, Laboratory of Ecotoxicology, Genomic and Evolution-Centre of Environmental and Marine Research, University of Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal
Department of Biology, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal
* Authors to whom correspondence should be addressed.
Received: 9 March 2011; in revised form: 28 April 2011 / Accepted: 9 May 2011 / Published: 10 May 2011
Abstract: Understanding potential biochemical interactions and effects among cyanobacteria and other organisms is one of the main keys to a better knowledge of microbial population structuring and dynamics. In this study, the effects of cyanobacteria from benthos and plankton of estuaries on other cyanobacteria and green algae growth were evaluated. To understand how the estuarine cyanobacteria might influence the dynamics of phytoplankton, experiments were carried out with the freshwater species Microcystis aeruginosa and Chlorella sp., and the marine Synechocystis salina and Nannochloropsis sp. exposed to aqueous and organic (70% methanol) crude extracts of cyanobacteria for 96 h. The most pronounced effect observed was the growth stimulation. Growth inhibition was also observed for S. salina and M. aeruginosa target-species at the highest and lowest concentrations of cyanobacterial extracts. The methanolic crude extract of Phormidium cf. chalybeum LEGE06078 was effective against S. salina growth in a concentration-dependent manner after 96 h-exposure. All of the cyanobacterial isolates showed some bioactivity on the target-species growth, i.e., inhibitory or stimulating effects. These results indicate that the analyzed cyanobacterial isolates can potentially contribute to blooms’ proliferation of other cyanobacteria and to the abnormal growth of green algae disturbing the dynamic of estuarine phytoplankton communities. Since estuaries are transitional ecosystems, the benthic and picoplanktonic estuarine cyanobacteria can change both freshwater and marine phytoplankton succession, competition and bloom formation. Furthermore, a potential biotechnological application of these isolates as a tool to control cyanobacteria and microalgae proliferation can be feasible. This work is the first on the subject of growth responses of photoautotrophs to cyanobacteria from Atlantic estuarine environments.
Keywords: allelopathy (negative); Atlantic estuarine environments; benthic; cyanobacteria; growth stimulation; picoplanktonic; Phormidium cf. chalybeum
Citations to this Article
Cite This Article
MDPI and ACS Style
Lopes, V.R.; Vasconcelos, V.M. Bioactivity of Benthic and Picoplanktonic Estuarine Cyanobacteria on Growth of Photoautotrophs: Inhibition versus Stimulation. Mar. Drugs 2011, 9, 790-802.
Lopes VR, Vasconcelos VM. Bioactivity of Benthic and Picoplanktonic Estuarine Cyanobacteria on Growth of Photoautotrophs: Inhibition versus Stimulation. Marine Drugs. 2011; 9(5):790-802.
Lopes, Viviana R.; Vasconcelos, Vitor M. 2011. "Bioactivity of Benthic and Picoplanktonic Estuarine Cyanobacteria on Growth of Photoautotrophs: Inhibition versus Stimulation." Mar. Drugs 9, no. 5: 790-802.