Actinomycetes isolation from soils and determination of the some biological activities

Actinomycetes bacterial group has the one of the most populous population in microorganisms that extends very different and extensive habitats especially natural soil habitats on earth. Since ancient times, bioactive metabolites of microorganisms especially soil microorganisms have studied and the results have provided that metabolites of soil microorganisms have significant benefits to science, medicine, agriculture and pharmaceutical industry. In this study, isolation of Actinomycetes strains from forest soils, identification of morpohological, biochemical and molecular features, extraction the bioactive metabolite of isolates and determination the antimicrobial, antibiofilm and cytotoxicity activities of bioactive extract was tested. The microbiological isolation methods for collected forest soil samples were used and after the determination of their morpfological, biochemical and molecular features, isolates were defined as Brevibacterium spp. that is member of Actinomycetes. It is known as an important species of Actinomycetes genus. The antibiotic resistance of the isolates were determined by different methods and different concentrations of standard antibiotics. The chromium tolerance of isolates were determined because Brevibacterium spp. is usually known by its tolerance against heavy metals. The bioactive metabolites of isolates were produced in modified medium and extracted. The antimicrobial, antibiofilm and cytotoxicity activities of different and serial concentrations of bioactive metabolite were determined against standard microorganisms and Artemia salina larvae were used as test organism for cytotoxicity researchs. The antimicrobial (MIC) concentrations of bioactive metabolite 2500 µg/mL for standard bacteria cultures and 1250 µg/mL for yeasts. The antibiofilm (MBEC) value was determined at 1250 µg/mL. The 2500 µg/mL concentration of extract was found the effective cytotoxic value. The results are provided that the Brevibacterium spp. isolates have industrial and pharmaceutical potential and more detailed pharmaceutical researchs are planned.