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Pushparaj, Benjamin; Pelosi, E.; Jüttner, Friedrich

doi:10.1023/a:1008080615337

“…As marine cyanobacteria tested in this research belong to Synechoccystis and Synechoccocus genera, our results emphasise the potential of these genera as a source of antibiotic compounds. In terms of antibacterial activity our results fits into the picture that antibacterial activity of cyanobacteria is primarily directed against Gram-positive bacteria [9,14]. This finding can be related to the fact that most Gram-negative bacteria are resistant to toxic agents in the environment due to the barrier of lipopolysaccharides of their outer membrane [27].…”

Section: Resultssupporting

confidence: 81%

“…Antimicrobial activity of cyanobacteria refer almost to filamentous strains belonging to a wide range of genera [6,[8][9][10]14,26]. Rao [6], working on the production of antibiotic compounds by filamentous forms of cyanobacteria, referred that the ability to produce antibiotic compounds might prevent bacterial contamination of the filaments and consequently pathogenic bacterial colonization.…”

Section: Resultsmentioning

confidence: 99%

Antimicrobial and Cytotoxic Assessment of Marine Cyanobacteria - Synechocystis and Synechococcus

Martíns

¹

2008

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Aqueous extracts and organic solvent extracts of isolated marine cyanobacteria strains were tested for antimicrobial activity against a fungus, Gram-positive and Gram-negative bacteria and for cytotoxic activity against primary rat hepatocytes and HL-60 cells. Antimicrobial activity was based on the agar diffusion assay. Cytotoxic activity was measured by apoptotic cell death scored by cell surface evaluation and nuclear morphology. A high percentage of apoptotic cells were observed for HL-60 cells when treated with cyanobacterial organic extracts. Slight apoptotic effects were observed in primary rat hepatocytes when exposed to aqueous cyanobacterial extracts. Nine cyanobacteria strains were found to have antibiotic activity against two Gram-positive bacteria, Clavibacter michiganensis subsp. insidiosum and Cellulomonas uda. No inhibitory effects were found against the fungus Candida albicans and Gram-negative bacteria. Marine Synechocystis and Synechococcus extracts induce apoptosis in eukaryotic cells and cause inhibition of Gram-positive bacteria. The different activity in different extracts suggests different compounds with different polarities.

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“…Although cyanobacteria are still primarily viewed as an environmental nuisance or a source of toxins, hazardous to man and aquatic livestock, there are many potential benefits to research on chemicals produced by these organisms. Antibacterial, antiviral, antifungal, algicide and cytotoxic activities have been reported [6][7][8][9][10][11]. The role of bioactive molecules in the producer organism itself is poorly understood but, considering the wide spectrum of biological adaptations and tolerance to environmental stress revealed by cyanobacteria, some of these compounds can be produced in an attempt to confer advantages for their survival.…”

Section: Introductionmentioning

confidence: 99%

“…Research on biological active compounds produced by cyanobacteria has been focused especially on freshwater species. Studies on marine species are more restricted and are specially related to filamentous forms from tropical regions [10], Baltic Sea [12] and Mediterranean Sea [9]. In this work we describe biological activities of marine cyanobacteria strains belonging to the genera Synechocystis and Synechococcus isolated from the temperate Atlantic coast of Portugal.…”

Section: Introductionmentioning

confidence: 99%

Antimicrobial and Cytotoxic Assessment of Marine Cyanobacteria - Synechocystis and Synechococcus

Martíns

¹

2008

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Aqueous extracts and organic solvent extracts of isolated marine cyanobacteria strains were tested for antimicrobial activity against a fungus, Gram-positive and Gram-negative bacteria and for cytotoxic activity against primary rat hepatocytes and HL-60 cells. Antimicrobial activity was based on the agar diffusion assay. Cytotoxic activity was measured by apoptotic cell death scored by cell surface evaluation and nuclear morphology. A high percentage of apoptotic cells were observed for HL-60 cells when treated with cyanobacterial organic extracts. Slight apoptotic effects were observed in primary rat hepatocytes when exposed to aqueous cyanobacterial extracts. Nine cyanobacteria strains were found to have antibiotic activity against two Gram-positive bacteria, Clavibacter michiganensis subsp. insidiosum and Cellulomonas uda. No inhibitory effects were found against the fungus Candida albicans and Gram-negative bacteria. Marine Synechocystis and Synechococcus extracts induce apoptosis in eukaryotic cells and cause inhibition of Gram-positive bacteria. The different activity in different extracts suggests different compounds with different polarities.

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“…Some researchers believe that cyanobacteria are capable of secreting some autostimulators that accelerate the development of the same species in the environment [54]. Moreover, it is commonly known that in laboratory experiments using monocultures, generally, cyanobacteria inhibit the growth of other cyanobacteria [55,56]; however, in natural assemblies, many co-occurring species could have developed some protective mechanisms against cyanobacterial metabolites and even benefit from them [57]. Our observations indicated that some Cyanophyceae (especially cyanobacteria from the genus Aphanothece, Limnothrix, Microcystis, and Synechococcus) may show tolerance for allelopathic compounds produced and released by freshwater Synechococcus sp., which may be the result of coevolution during their coexistence in some freshwater ecosystem.…”

Section: Discussionmentioning

confidence: 99%

The Importance of Allelopathic Picocyanobacterium Synechococcus sp. on the Abundance, Biomass Formation, and Structure of Phytoplankton Assemblages in Three Freshwater Lakes

Bubak

¹

,

Śliwińska‐Wilczewska

²

,

Głowacka

³

et al. 2020

Toxins

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The contribution of picocyanobacteria to summer phytoplankton blooms, accompanied by an ecological crisis, is a new phenomenon in Europe. This issue requires careful investigation. We studied allelopathic activity of freshwater picocyanobacterium Synechococcus sp. on phytoplankton assemblages from three freshwater lakes. In this study, the allelopathic activity of the Synechococcus sp. on the total abundance, biomass, as well as structure of the phytoplankton assemblages were investigated. Our results indicated that addition of exudates obtained from Synechococcus sp. affected the number of cells and biomass of the phytoplankton communities; the degree of inhibition or stimulation was different for each species, causing a change in the phytoplankton abundance and dominance during the experiment. We observed that some group of organisms (especially cyanobacteria from the genus Aphanothece, Limnothrix, Microcystis, and Synechococcus) showed tolerance for allelopathic compounds produced and released by Synechococcus sp. It is also worth noting that in some samples, Bacillariophyceae (e.g., Amphora pediculus, Navicula pygmaea, and Nitzschia paleacea) were completely eliminated in the experimental treatments, while present in the controls. This work demonstrated that the allelopathic activity exhibited by the Synechococcus sp. is probably one of the major competitive strategies affecting some of the coexisting phytoplankton species in freshwater ecosystems. To our best knowledge this is the first report of the allelopathic activity of Synechococcus sp. in the freshwater reservoirs, and one of the few published works showing allelopathic properties of freshwater picocyanobacteria on coexisting phytoplankton species.

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Cited by 37 publications

References 17 publications

Antimicrobial and Cytotoxic Assessment of Marine Cyanobacteria - Synechocystis and Synechococcus

Antimicrobial and Cytotoxic Assessment of Marine Cyanobacteria - Synechocystis and Synechococcus

Antimicrobial and Cytotoxic Assessment of Marine Cyanobacteria - Synechocystis and Synechococcus

The Importance of Allelopathic Picocyanobacterium Synechococcus sp. on the Abundance, Biomass Formation, and Structure of Phytoplankton Assemblages in Three Freshwater Lakes

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