Antimicrobial and Cytotoxic Assessment of Marine Cyanobacteria - Synechocystis and Synechococcus

Abstract

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.

Baltic cyanobacteria – a source of biologically active compounds

“…Significant activity was found mainly among the representatives of the Nostocales, Oscilatorialles and Chroococalles. Similarly to this study, Martins et al (2008) tested the effects of aqueous and organic solvent extracts from 14 strains of Synechococcus and Synechocystis (Chroococalles). Nine of the extracts inhibited the growth of Grampositive bacteria (Clavibacter michiganensis subsp.…”

Current perspectives on the dynamics of antibiotic resistance in different reservoirs

“…were effective against vancomycin-resistant Staphylococcus aureus [27]. Some authors consider that cyanobacteria antibacterial activity is more effective against Gram-positive bacteria [28,29] than Gram-negative, attributed to the protection conferred by the lipopolysaccharide barrier of the Gramnegative cell wall [28]; however, some Gram-negative bacteria, including pathogenic species, are also affected by cyanobacterial compounds. The potential application of bacterial compounds to the development of new antimicrobials therefore appears to be a promising research area.…”

Anti-tumor effect of C-phycocyanin from Anabaena sp.ISC55 in inbred BALB/c mice injected with 4T1 breast cancer cell

“…Today, it is known that the consumption of natural foods or products, which have anti-oxidant properties, can prevent cancer or reduce the risk of its occurrence (Namiki 1990). Cyanobacteria, also known as blue-green algae (BGA), are a class of gram-negative bacteria with some species that own anticancer properties including Nostoc, Fhormidium, Gloeocapsa, Anabaena, Spirulina, Synechocystis, and Synechococcus (Gigova et al 2011;Martins et al 2008;Surakka et al 2005;Oh et al 2011). Phycobilisomes are large supramolecular aggregates attached to the thylakoid membrane of cyanobacteria (blue-green algae) and rhodophyta (red algae) that function in light harvesting and energy migration (Román et al 2002;MacColl 1998;Apt et al 1995).…”