Screening of Thermophilic Cyanobacteria from some hot Springs of Iran

Hot springs have been a subject of intense discussion for biologists in the last decades. The polyphasic approach is the most progressive system that has been suggested for distinguishing and phylogenetically classifying cyanobacteria. In a revision of the cyanobacteria in hot springs of Iran, four hot springs of Iran were investigated. We developed a combined molecular and morphological approach to identification of cyanobacteria. In this study seventeen populations and 13 morphological characters were analyzed. Molecular study based on 16S rRNA gene sequence does not disrupt morphological information and it confirms the separation of studied taxa according to morphological characters. Based on their growth characteristics; seven species were selected for the production of antimicrobial agents. The results of this study showed that the methanol extracts exhibited high antimicrobial activity against some gram positive bacteria, moderate antibacterial activity against some gram negative organisms and moderate antifungal activity against some fungi. Four species were selected for salinity tolerance. The results showed high tolerance of these taxa to salinity.