Screening of antioxidant activity of cyanobacteria speciesisolated from Khoor-e-Khooran mangrove forest, Persian Gulf, Iran

Background and Aim : Cyanobacteria are photoautotrophic oxygenic bacteria that have acquiredspecial attention due to their nutraceuticals and medical importance. Microbial antioxidants arenoncarcinogenic, non toxic and biodegradable compounds compared to synthetic antioxidants. Theaim of this study was to evaluate the antioxidant activity of isolated cyanobacteria from the Khoore-Khooran mangrove forests.Methods : Water samples were collected from ۱۲ selected stations from ۲۵ cm below the surfacein a ۵۰۰ mL dark glass bottle. ۱۰۰ μL of each sample was inoculated on the BG ۱۱ medium andincubated at ۲۸˚C under ۱۲ hours light and ۱۲ hours darkness for ۲ weeks. The purified isolateswere identified according to morphological characteristics. DPPH radical scavenging activity ofthe isolated bacteria were determined based on the microdilution method.Results : We isolated ۵۱ cyanobacterial isolates from collected water samples. Phormidium andOscillatoria were dominant genera with frequency percentages of ۴۵% and ۳۵% respectively. Theantioxidant determination of extracted metabolites from the isolated cyanobacteria showed that۲۴% of the isolates scavenged DPPH radicals with IC۵۰ values ranged from ۴۶.۱ to ۶۷۶.۴ μg/ml.Conclusion : These results revealed cyanobacterial diversity of the exploration area in the Khoore-Khooran mangrove wetland. The potent strains could be considered as potential sources ofmicrobial antioxidants in future studies.

کلیدواژه ها:

Marine cyanobacteria ، Microbial antioxidants ، Mangrove forests ، Persian Gulf