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چکیده
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The resistant pathogenic bacteria to antibiotics are a major universal problem these days and the effort to discover new antibiotics seems to be necessary. Accordingly, two marine sponges, Halicona simulans and dictyonella sp, has been collected by diving in depth of 10-15 meters of the waters around the Kharko island in order to obtain actinomycetes Associated with sponge that has the capability of antibiotic compounds production. An amount of the inner mesohyl tissue of each sponge has been homogenized and in the Marin Agar cultivations environment, SDA and EA, has been cultured. Eight actinomycetes strains have been identified morphologically and biochemically and then the molecular identification of those has been performed by using sequencing 16s rDNA gene. The nearest available strains in NCBI to the strains obtained in this research were Brevibacterium ravenspurgense strain 20, Streptomyces nanhaiensis strain SCSIO 01248, Kocuria marina strain KMM 3905, Nocardiopsis coralliicola strain SCSIO 10427, Micromonospora rifamycinica strain AM105, Streptomyces xiamenensis strain MCCC 1A01550, Micrococcus yunnanensis strain YIM 65004, Actinokineospora fastidiosa strain NRRL B16697, respectively. After the molecular identification, the antibacterial activity screening has been done by two cross streak and disk diffusion methods. The results of these tests showed that the number four and seven strains were the best strains. In the next step, the antifungal activity screening has been done by two methods: Disk-Agar and disk diffusion. The results of Disk-Agar test showed that the number four, six, seven and eight strains had the most antifungal activity. The chloroform and methanol extract of these strains has been used for disk diffusion test and the result of this test showed the chloroform extract inactivity of these strains on the fungus tested and among the methanol extracts the most strength was related to the number four strain. With respect to high power of the n
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