الفعالية الضد بكتيرية لبعض السيانوبكتريا في محافظة البصرة في العراق

الملخص EN

Six species of cyanobacteria: Chroococcus limneticus , Microcystis aeruginosa , Merismopedia Trolleri , Oscillatoria sp., Anabaena cylinderica and Tolypothrix nodosa.

were isolated from different locations in Basrah.Hexane, chloroform, methanol extracts of those species were tested to detect their ability on growth inhibit of some representatives of Gram-negative and Gram-positive bacteria.

Methanol extracts of T.nodosa showed higher inhibitory effect, whereas hexane extracts of M.

Trolleri , Oscillatoria sp.

showed moderate antibacterial activity.

Chloroform extracts present the lowest antibacterial activity of A.

cylindrical .Methanol extract of T.

nodosa was selected for the identification of bioactive compounds depending on the bioactive compounds tests and spectroscopic analyses including: Infrared (IR); Nuclear Magnetic Resonance spectroscopy (NMR); and Gas Chromatography/ Mass spectrum (GC/MS) the.

Results indicate that one compound is a nucleoside which is derivative of tubercidin .

T.

nodosa was selected to improve its productivity by exposing to gamma radiation at different doses, and sub culturing the strain which have high productivity and antibacterial activity ,the results showed that the dose 2.8 gray was the most effective.

The symbol TG4 was given to the mutant strain with the highest productivity and antibacterial activity.

By using the previous methods of chemical compounds identification, the bioactive compound was alkaloid.

MIC and cytotoxicity of both compounds were done.