Screening of Thermophilic Cyanobacteria from some hot Springs of Iran

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