Evaluation of the antibiotic production ability of the bacteria species Halomonas azerica, Halomonas azerbayjanica, Halomonas sp. TBZ224

Abstract

Introduction: Halomonas bacterial species live in saline waters, which can produce valuable primary and secondary metabolites to adapt to environmental conditions and survive in harsh conditions. Secondary metabolites such as various antibiotics have been produced by halophilic bacteria, which have shown the property of inhibiting the growth of bacterial pathogens. Therefore, considering the importance of finding new sources of antibiotics, in this study, the ability to produce compounds with antibacterial properties by Halomonas bacteria isolated from the waters of Lake Urmia was investigated. Objective: Evaluation of the antibiotic production ability of the bacteria species Halomonas azerica, Halomonas azerbayjanica, Halomonas sp.TBZ224. Methods: In this thesis, first the bacteria Halomonas azerica, Halomonas azerbayjanica, Halomonas sp. TBZ224 isolated from the waters of Lake Urmia were cultured and after drawing the growth curve of the bacteria, the stationary phase of the growth of the bacteria was investigated. Then, after taking samples from different days of bacterial growth, the secretions of these bacteria were extracted in the supernatant and their antibiotic effects against pathogens E.Coli, Pseudomonas aeruoginosa, and Staphylococcus aureus were investigated.Results: Halomonas species secondary metabolites showed modest antibiotic effect against human pathogens including Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. Some of these antibiotic effects are related to their secreted exopolysaccharides.Conclusion: The results show that lake Urmia water can be a source of microorganisms that are useful in biotechnology because they produce secondary metabolites and exopolysaccharides with antibiotic potential.