Antibacterial Activity of Anabaena circinalis Isolated from Fresh Water
Hanan. M. Abobaker *
Department of Botany, Faculty of Science, Omar El-Mokhtar University, El–Beyda, Libya.
Hamida. EL. Elsalhin
Department of Botany, Faculty of Science, Omar El-Mokhtar University, El–Beyda, Libya.
*Author to whom correspondence should be addressed.
Abstract
Cultures of the blue green algae (cyanobacteria) Anabaena circinalis were identified and isolated from freshwater and their antimicrobial effect was studied. The extract of A. circinalis was tested to investigate its efficiency against four bacterial strains (Achromobacter xylosoxidans, Staphylococcus aureus, Escherichia coli, Shigella dysenteriae. Antimicrobial test was determined by disk diffusion method. Different concentrations of algal extracts (25, 50, 75 and 100%) were tested. Results showed that the highest level of antimicrobial activity was recorded against S. dysenteriae at 100% concentration followed by 25% extract concentration against the same bacteria. In comparison with two antibiotics Ampicillin (AMP), oxacilina (OXA), AMP was the most effective on S. dysenteriae followed by OXA. S. aureus and E. coli were resistant to both antibiotics while they were sensitive to A. circinalis extracts at even at low concentrations (25% and 50%). Thus the present study revealed that extracts of A. circinalis extract is would be a promising natural source, for novel antibiotics, hence worthy for more investigations.
Keywords: Anabaena circinalis, antimicrobial, algal extract, Ampicillin, oxacilina