Microbiology
fatemeh alinejad; Gholam Khodakaramian
Abstract
Introduction: The majority of antibiotics that are used today are produced by actinomycetes, especially the genus of Streptomyces. Because of the high potential of Streptomyces species to produce antimicrobial compounds, these bacteria are still an interesting source for identifying new antimicrobial ...
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Introduction: The majority of antibiotics that are used today are produced by actinomycetes, especially the genus of Streptomyces. Because of the high potential of Streptomyces species to produce antimicrobial compounds, these bacteria are still an interesting source for identifying new antimicrobial compounds. Due to the influence of environmental micro factors on microbial communities and their gene expression, including the synthesis of secondary and antimicrobial compounds, it is valuable to isolate Streptomyces from unique environments for identifying new compounds. The rhizosphere of wild traditional medicinal plants appears to be a promising environment for the isolation and identification of Streptomyces, as well as the discovery of new compounds... In this study, we investigated the antimicrobial activity of Streptomyces isolates collected from the rhizosphere of native medicinal plants in Hamedan province against Gram-positive and Gram-negative bacteria. Methods: Different isolates of Streptomyces were collected from the rhizosphere of medicinal plants in the Averzaman region in Hamedan province, and their antimicrobial activity against Gram-positive and Gram-negative bacteria was investigated using bioassay tests. Metabolomics analysis of the extracts obtained from the liquid culture of the active isolates was performed using ESI-MS to identify active compounds corresponding to the observed bioactivities. Results and Discussion: Based on bioassay tests, the Streptomyces sp. 3Z isolated from the rhizosphere of Mentha longifolia exhibited strong antimicrobial activity against Gram-positive and Gram-negative bacteria. Metabolomics analysis of the active fraction of the crude extract of this isolate confirmed the production of Streptothricin D by this isolate.
