Diversity and Antimicrobial Activities of Streptomyces Isolated from intertidal Sediments of Deylam, Iran

Actinomycetes have significant biosynthetic potential of secondary metabolites and promising resource for drug industry. These secondary metabolitesare diverse in biological, chemical structures and functions and the most prolific source of antimicrobial compounds. Most of these antimicrobial have beenisolated from soil-derived actinomycetes of the genus Streptomyces. The aim of this study was to isolate and identify Actinobacteria from Deylam intertidal sediments using 16S rDNA universal primers and screening of isolates for production of antimicrobial secondary metabolites by using disk palate assay.
Six isolates were isolated from soil samples collected from different sites. Allsix isolates were considered as Streptomyces sp. according to phylogentic study based on 16S rDNA gene. Isolates were analyzed for production of potent antimicrobial secondary metabolites using standard disk and well assay.
Results showed that none of isolates supernatant had inhibitory effect on P. vulgarisand Klebsilla sp. the most inhibition zone of pathogenic bacteria was shown by AHA5 against S. typhi (9.2 mm). Altogether isolates supernatant showed more antifungal activity in comparison with antibacterial activity and the most inhibition zone was demonstrated by AHA1 supernatant against T. mentagrophytes pathogenic fungi with 21 mm diameters of zone of inhibition.
Our results highlighted thatmangrove Deylam intertidal sediments represented a reservoir for isolation of Actinobacteria, which are potential sources for discovery of antimicrobial secondarymetabolites.