Isolation, identification and determination of antibiotics production capacity of actinomycetes from bor mines in Turkey

Although 72% of world's bor reserves are in Turkey, there are no studies related to actinobacteria here. This study is aimed to determine the potential of antibiotics production of actinobacteria as well as filling the gap in the literature in this area via characterization of actinobacteria isolated from bor mines in Turkey. Actinobacteria strains were purified and their tolerances to bor have been determined as a result of samplings performed in mines located in different areas of Turkey primarily including Emet, Kırka, and Bigadiç Bor Operating Managements. Ethyl acetate extracts (1:1 v/v) has been obtained after 1 week fermantation inside a liquid medium containing the optimum bor concentration of the isolates and activities of extracts were examined by using the disk diffusion method against the antibiotic resistant test organism. Fermantations of active strains were repeated at different bor concentrations and TLC profiles of ethyl acetate extracts were determined. Various phenotypic tests and 16S rRNA sequence analysis were performed to identify the potent strains. Eventually, a total of 24 actinobacteria strains from 3 different mines were purified and after their tolerance studies, it has been determined that strain no. B2-1 has the highest growth rate at 175 Mm bor concentration. 6 of the isolates were determined as antibiotics-producing strains after antimicrobial activity screening and all these isolates were identified as belonging to the genus Streptomyces following the identification of these strains by cultural and molecular methods. Keywords: Bor, Actinobacteria, Antibiotics production