Isolation of Actinobacteria Strains From Environmental Samples and Assessment of Their Bioactivity

Background: Actinobacteria are widespread and live in a variety of habitats. Today, these bacteria arevery important due to the production of various secondary metabolites with different biological activities.The present study aimed to isolate strains of Actinobacteria from different habitats (the Persian Gulf,Gandom Beryan area in the Lut Desert, and some plant roots). The anticancer and antimicrobial activitiesof secondary metabolites of these isolates were also investigated.Methods: Samples were taken from water of the Persian Gulf, soil of Gandom Beryan area in the LutDesert, and plant roots. For isolation of Actinobacteria, samples were cultured in ISP۲, ISP۴, AIA, Gauze,M۱, ISP۳, and GYP media. Bacterial strains were identified based on the colony and bacterial morphologyand confirmed using the specific primers for Actinobacteria. The anticancer and antimicrobial activities ofcrude metabolite extracts and supernatant of the isolates were evaluated on MCF-۷ and Staphylococcusaureus PTCC ۱۱۲ and Pseudomonas aeruginosa PTCC ۱۲۱۴ strains.Results: The results showed that the supernatants of ۷ isolates (ga۳۱, ez, sa, mar۲, rz, ga۳۳, and ga۵)and the metabolite extracts of ۴ strains (ga۳۱, ga۵, rz, and ez) had anticancer activity. Overall, ga۳۱ wasthe best strain with anticancer activity of more than ۷۵%. When evaluating the antimicrobial activity ofbacterial secondary metabolites, we found that only two strains (ga۳۱ and ga۵) had antimicrobial activityagainst S. aureus PTCC ۱۱۱۲.Conclusions: In general, strain ga۳۱, which has high anticancer and antimicrobial activities, could be agood candidate for new trials in the pharmaceutical industry.

Keywords:

Actinobacteria , Anticancer , Antimicrobial , Secondary metabolite , Persian Gulf