Author(s): Ghaidaa H. Abd, Neihaya H. Zaki* and Merthad A. S.
In this study, Oscillatoria tenius isolated and identified from Al-Mustansiriyah University gardens, BG-11 culture media used for their cultivation in suitable laboratory conditions [(25c°, 200 µE/m 2 /sec) for 16:8 h. Light: dark], each culture harvested at the end of two weeks. Organic solvents used for extraction was 95 % (Ethanol, Acetone, Hexane), study aims to test the effectiveness of extracted intracellular (biomass) and Extracellular (filtrate) products and test their effectiveness against 10 strains of bacteria: seven of them gram negative bacteria (Enterobacter spp., Serratia spp., Acinetobacter spp., Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Salmonella typhi) and three gram positive bacteria (Staphylococcus aureus, Streptococcus spp., and Micrococcus luteus) by agar well diffusion method. Results showed that the intracellular extract was best than extracellular, and sensitivity of all bacteria to intracellular ethanol extract was better than others. It recorded the best inhibition of K. pneumonia at a rate of 36 mm, then Enterobacter spp. was 30 mm, while intracellular extract by acetone not shown the effectiveness of inhibition against the bacteria were tested. Chemical analysis showed that active compounds were present in intracellular extracts in all samples of studied algae by using Gas-Liquid Chromatography.